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  • 1.
    Akimoto, Chizuru
    et al.
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Forsgren, Lars
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Linder, Jan
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Birve, Anna
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Backlund, Irene
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Andersson, Jörgen
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Nilsson, Ann-Charloth
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Alstermark, Helena
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Andersen, Peter M
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    No GGGGCC-hexanucleotide repeat expansion in C9ORF72 in parkinsonism patients in Sweden2013In: Amyotrophic Lateral Sclerosis and Frontotemporal Degeneration, ISSN 2167-8421, Vol. 14, no 1, p. 26-29Article in journal (Refereed)
    Abstract [en]

    An intronic GGGGCC-hexanucleotide repeat expansion in C9ORF72 was recently identified as a major cause of amyotrophic lateral sclerosis and frontotemporal dementia. Some amyotrophic lateral sclerosis patients have signs of parkinsonism, and many parkinsonism patients develop dementia. In this study we examined if the hexanucleotide repeat expansion was present in parkinsonism patients, to clarify if there could be a relationship between the repeat expansion and disease. We studied the size of the hexanucleotide repeat expansion in a well defined population-based cohort of 135 Parkinson's disease patients and 39 patients with atypical parkinsonism and compared with 645 Swedish control subjects. We found no correlation between Parkinson's disease or atypical parkinsonism and the size of the GGGGCC repeat expansion in C9ORF72. In conclusion, this GGGGCC-repeat expansion in C9ORF72 is not a cause of parkinsonism in the Swedish population.

  • 2. Berge-Seidl, Victoria
    et al.
    Pihlstrøm, Lasse
    Maple-Grødem, Jodi
    Forsgren, Lars
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Linder, Jan
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Larsen, Jan Petter
    Tysnes, Ole-Bjørn
    Toft, Mathias
    The GBA variant E326K is associated with Parkinson's disease and explains a genome-wide association signal2017In: Neuroscience Letters, ISSN 0304-3940, E-ISSN 1872-7972, Vol. 658, p. 48-52Article in journal (Refereed)
    Abstract [en]

    Objective: Coding variants in the GBA gene have been identified as the numerically most important genetic risk factors for Parkinson's disease (PD). In addition, genome-wide association studies (GWAS) have identified associations with PD in the SYT11-GBA region on chromosome 1q22, but the relationship to GBA coding variants have remained unclear. The aim of this study was to sequence the complete GBA gene in a clinical cohort and to investigate whether coding variants within the GBA gene may be driving reported association signals. Methods: We analyzed high-throughput sequencing data of all coding exons of GBA in 366 patients with PD. The identified low-frequency coding variants were genotyped in three Scandinavian case-controls series (786 patients and 713 controls). Previously reported risk variants from two independent association signals within the SYT11-GBA locus on chromosome 1 were also genotyped in the same samples. We performed association analyses and evaluated linkage disequilibrium (LD) between the variants. Results: We identified six rare mutations (1.6%) and two low-frequency coding variants in GBA. E326K (rs2230288) was significantly more frequent in PD patients compared to controls (OR 1.65, p = 0.03). There was no clear association of T369M (rs75548401) with disease (OR 1.43, p = 0.24). Genotyping the two GWAS hits rs35749011 and rs114138760 in the same sample set, we replicated the association between rs35749011 and disease status (OR 1.67, p = 0.03), while rs114138760 was found to have similar allele frequencies in patients and controls. Analyses revealed that E326K and rs35749011 are in very high LD (r(2) 0.95). Conclusions: Our results confirm that the GBA variant E326K is a susceptibility allele for PD. The results suggest that E326K may fully account for the primary association signal observed at chromosome 1q22 in previous GWAS of PD.

  • 3.
    Blomstedt, Patric
    et al.
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Fytagoridis, Anders
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Linder, Jan
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Forsgren, Lars
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Hariz, Marwan
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Unilateral caudal Zona incerta deep brain stimulation for Parkinsonian tremor2012In: Parkinsonism & Related Disorders, ISSN 1353-8020, E-ISSN 1873-5126, Vol. 18, no 10, p. 1062-1066Article in journal (Other academic)
    Abstract [en]

    Background: The subthalamic nucleus is currently the target of choice in deep brain stimulation (DBS) for Parkinson's disease (PD), while thalamic DBS is used in some cases of tremor-dominant PD. Recently, a number of studies have presented promising results from DBS in the posterior subthalamic area, including the caudal zona incerta (cZi). The aim of the current study was to evaluate cZi DBS in tremor-dominant Parkinson's disease.

    Methods: 14 patients with predominately unilateral tremor-dominant PD and insufficient relief from pharmacologic therapy were included and evaluated according to the motor part of the Unified Parkinson Disease Rating Scale (UPDRS). The mean age was 65 ± 6.1 years and the disease duration 7 ± 5.7 years. Thirteen patients were operated on with unilateral cZi DBS and 1 patient with a bilateral staged procedure. Five patients had non-L-dopa responsive symptoms. The patients were evaluated on/off medication before surgery and on/off medication and stimulation after a minimum of 12 months after surgery.

    Results: At the follow-up after a mean of 18.1 months stimulation in the off-medication state improved the contralateral UPDRS III score by 47.7%. Contralateral tremor, rigidity, and bradykinesia were improved by 82.2%, 34.3%, and 26.7%, respectively. Stimulation alone abolished tremor at rest in 10 (66.7%) and action tremor in 8 (53.3%) of the patients.

    Conclusion: Unilateral cZi DBS seems to be safe and effective for patients with severe Parkinsoniantremor. The effects on rigidity and bradykinesia were, however, not as profound as in previous reports of DBS in this area.

  • 4.
    Blomstedt, Patric
    et al.
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Lindvall, Peter
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Linder, Jan
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Olivecrona, Magnus
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Forsgren, Lars
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Hariz, Marwan I.
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Reoperation after failed deep brain stimulation for essential tremor2012In: World Neurosurgery, ISSN 1878-8750, Vol. 78, no 5, p. 554.e1-554.e5Article in journal (Refereed)
    Abstract [en]

    OBJECTIVE: To evaluate the effects of reoperation with deep brain stimulation (DBS) in the caudal zona incerta (cZi) in patients with failed DBS in the ventral intermediate (Vim) nucleus of the thalamus for essential tremor. METHODS: The results of reoperation with cZi DBS in five patients with failed Vim DBS were retrospectively analyzed. RESULTS: Two patients had early failure of Vim DBS, and three after several years of good effect. The mean deviation from the atlas Vim target point was 1.4 mm. Before the reoperation Vim DBS improved hand function and tremor in the treated hand at 25 %, whereas cZi DBS achieved an improvement of 57%. Although cZi was more efficient than Vim DBS, also in the patients with late failure of Vim DBS, they still exhibited a considerable residual tremor on cZi DBS. CONCLUSIONS: The effect on tremor was, in this small sample population, improved by implanting an electrode in the cZi. The effect was modest in those patients suffering a deterioration years after the initial operation.

  • 5.
    Blomstedt, Patric
    et al.
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Neurosurgery.
    Sandvik, Ulrika
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Neurosurgery.
    Linder, Jan
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Neurology.
    Fredricks, Anna
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Neurology.
    Forsgren, Lars
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Neurology.
    Hariz, Marwan
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Neurosurgery.
    Deep brain stimulation of the subthalamic nucleus versus the zona incerta in the treatment of essential tremor2011In: Acta Neurochirurgica, ISSN 0001-6268, E-ISSN 0942-0940, Vol. 153, no 12, p. 2329-2335Article in journal (Refereed)
    Abstract [en]

    Background: Deep brain stimulation (DBS) is an effective treatment for essential tremor (ET). Currently the ventrolateral thalamus is the target of choice, but the posterior subthalamic area (PSA), including the caudal zona incerta (cZi), has demonstrated promising results, and the subthalamic nucleus (STN) has been suggested as a third alternative. The objective of the current study was to evaluate the effect of STN DBS in ET and to compare this to cZi DBS.

    Methods: Four patients with ET were implanted with two ipsilateral electrodes, one in the STN and one in the cZi. All contacts were evaluated concerning the acute effect on tremor, and the effect of chronic DBS in either target was analyzed.

    Results: STN and cZi both proved to be potent targets for DBS in ET. DBS in the cZi was more efficient, since the same degree of tremor reduction could here be achieved at lower energy consumption. Three patients became tremor-free in the treated hand with either STN or cZi DBS, while the fourth had a minor residual tremor after stimulation in either target.

    Conclusion: In this limited material, STN DBS was demonstrated to be an efficient treatment for ET, even though cZi DBS was more efficient. The STN may be an alternative target in the treatment of ET, pending further investigations to decide on the relative merits of the different targets.

  • 6.
    Blomstedt, Patric
    et al.
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Stenmark Persson, Rasmus
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Hariz, Gun-Marie
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Occupational Therapy. Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Linder, Jan
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Fredricks, Anna
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Häggström, Björn
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Philipson, Johanna
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Forsgren, Lars
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Hariz, Marwan
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience. Unit of Functional Neurosurgery, UCL Institute of Neurology, London, UK.
    Deep brain stimulation in the caudal zona incerta versus best medical treatment in patients with Parkinson's disease: a randomised blinded evaluation2018In: Journal of Neurology, Neurosurgery and Psychiatry, ISSN 0022-3050, E-ISSN 1468-330X, Vol. 89, no 7, p. 710-716Article in journal (Refereed)
    Abstract [en]

    Background: Several open-label studies have shown good effect of deep brain stimulation (DBS) in the caudal zona incerta (cZi) on tremor, including parkinsonian tremor, and in some cases also a benefit on akinesia and axial symptoms. The aim of this study was to evaluate objectively the effect of cZi DBS in patients with Parkinson's disease (PD).

    Method: 25 patients with PD were randomised to either cZi DBS or best medical treatment. The primary outcomes were differences between the groups in the motor scores of the Unified Parkinson's Disease Rating Scale (UPDRS-III) rated single-blindly at 6 months and differences in the Parkinson's Disease Questionnaire 39 items (PDQ-39). 19 patients, 10 in the medical arm and 9 in the DBS arm, fulfilled the study.

    Results: The DBS group had 41% better UPDRS-III scores off-medication on-stimulation compared with baseline, whereas the scores of the non-surgical patients off-medication were unchanged. In the on-medication condition, there were no differences between the groups, neither at baseline nor at 6 months. Subitems of the UPDRS-III showed a robust effect of cZi DBS on tremor. The PDQ-39 domains 'stigma' and 'ADL' improved only in the DBS group. The PDQ-39 summary index improved in both groups.

    Conclusion: This is the first randomised blinded evaluation of cZi DBS showing its efficacy on PD symptoms. The most striking effect was on tremor; however, the doses of dopaminergic medications could not be decreased. cZi DBS in PD may be an addition to existing established targets, enabling tailoring the surgery to the needs of the individual patient.

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  • 7.
    Bäckström, David C
    et al.
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Eriksson Domellöf, Magdalena
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Linder, Jan
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Olsson, Bob
    Öhrfelt, Annika
    Trupp, Miles
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Zetterberg, Henrik
    Blennow, Kaj
    Forsgren, Lars
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Cerebrospinal Fluid Patterns and the Risk of Future Dementia in Early, Incident Parkinson Disease2015In: JAMA Neurology, ISSN 2168-6149, E-ISSN 2168-6157, Vol. 72, no 10, p. 1175-1182Article in journal (Refereed)
    Abstract [en]

    IMPORTANCE: Alterations in cerebrospinal fluid (CSF) have been found in Parkinson disease (PD) and in PD dementia (PDD), but the prognostic importance of such changes is not well known. In vivo biomarkers for disease processes in PD are important for future development of disease-modifying therapies. OBJECTIVE: To assess the diagnostic and prognostic value of a panel of CSF biomarkers in patients with early PD and related disorders. DESIGN, SETTING, AND PARTICIPANTS: Regional population-based, prospective cohort study of idiopathic parkinsonism that included patients diagnosed between January 1, 2004, and April 30, 2009, by amovement disorder team at a university hospital that represented the only neurology clinic in the region. Participants were 128 nondemented patients with new-onset parkinsonism (104 with PD, 11 with multiple system atrophy, and 13 with progressive supranuclear palsy) who were followed up for 5 to 9 years. At baseline, CSF from 30 healthy control participants was obtained for comparison. MAIN OUTCOMES AND MEASURES: Cerebrospinal fluid concentrations of neurofilament light chain protein, Aβ1-42, total tau, phosphorylated tau, α-synuclein, and heart fatty acid-binding protein were quantified by 2 blinded measurements (at baseline and after 1 year). Follow-up included an extensive neuropsychological assessment. As PD outcome variables, mild cognitive impairment and incident PDD were diagnosed based on published criteria. RESULTS: Among the 128 study participants, the 104 patients with early PD had a different CSF pattern compared with the 13 patients with progressive supranuclear palsy (baseline area under the receiver operating characteristic curve, 0.87; P < .0001) and the 30 control participants (baseline area under the receiver operating characteristic curve, 0.69; P = .0021). A CSF biomarker pattern associated with the development of PDD was observed. In PD, high neurofilament light chain protein, low Aβ1-42, and high heart fatty acid-binding protein at baseline were related to future PDD as analyzed by Cox proportional hazards regression models. Combined, these early biomarkers predicted PDD with high accuracy (hazard ratio, 11.8; 95% CI, 3.3-42.1; P = .0001) after adjusting for possible confounders. CONCLUSIONS AND RELEVANCE: The analyzed CSF biomarkers have potential usefulness as a diagnostic tool in patients with parkinsonism. In PD, high neurofilament light chain protein, low Aβ1-42, and high heart fatty acid-binding protein were related to future PDD, providing new insights into the etiology of PDD.

  • 8.
    Bäckström, David C
    et al.
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Linder, Jan
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Jakobson Mo, Susanna
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology. Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI).
    Riklund, Katrine
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology. Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI).
    Zetterberg, Henrik
    Blennow, Kaj
    Forsgren, Lars
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Lenfeldt, Niklas
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Neurofilament concentration in CSF correlates with disease severity, survival and imaging measures of neurodegeneration in incident Parkinson diseaseManuscript (preprint) (Other academic)
  • 9.
    Bäckström, David C
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Neurosciences.
    Linder, Jan
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Neurosciences.
    Jakobson Mo, Susanna
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology. Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI).
    Riklund, Katrine
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology. Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI).
    Zetterberg, Henrik
    Blennow, Kaj
    Forsgren, Lars
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Neurosciences.
    Lenfeldt, Niklas
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Neurosciences.
    NfL as a biomarker for neurodegeneration and survival in Parkinson disease2020In: Neurology, ISSN 0028-3878, E-ISSN 1526-632X, Vol. 95, no 7, p. e827-e838Article in journal (Refereed)
    Abstract [en]

    OBJECTIVE: To determine whether neurofilament light chain protein in CSF (cNfL), a sensitive biomarker of neuroaxonal damage, reflects disease severity or can predict survival in Parkinson disease (PD).

    METHODS: We investigated whether disease severity, phenotype, or survival in patients with new-onset PD correlates with cNfL concentrations around the time of diagnosis in the population-based New Parkinsonism in Umeå (NYPUM) study cohort (n = 99). A second, larger new-onset PD cohort (n = 194) was used for independent validation. Association of brain pathology with the cNfL concentration was examined with striatal dopamine transporter imaging and repeated diffusion tensor imaging at baseline and 1 and 3 years.

    RESULTS: Higher cNfL in the early phase of PD was associated with greater severity of all cardinal motor symptoms except tremor in both cohorts and with shorter survival and impaired olfaction. cNfL concentrations above the median of 903 ng/L conferred an overall 5.8 times increased hazard of death during follow-up. After adjustment for age and sex, higher cNfL correlated with striatal dopamine transporter uptake deficits and lower fractional anisotropy in diffusion tensor imaging of several axonal tracts.

    CONCLUSIONS: cNfL shows usefulness as a biomarker of disease severity and to predict survival in PD. The present results indicate that the cNfL concentration reflects the intensity of the neurodegenerative process, which could be important in future clinical trials.

    CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that in patients with PD, cNfL concentrations are associated with more severe disease and shorter survival.

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  • 10.
    Bäckström, David
    et al.
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Eriksson Domellöf, Magdalena
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Granåsen, Gabriel
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Epidemiology and Global Health.
    Linder, Jan
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Mayans, Sofia
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Elgh, Eva
    Umeå University, Faculty of Social Sciences, Department of Psychology.
    Jakobson Mo, Susanna
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology.
    Forsgren, Lars
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    PITX3 genotype and risk of dementia in Parkinson's disease: A population-based study2017In: Journal of the Neurological Sciences, ISSN 0022-510X, E-ISSN 1878-5883, Vol. 381, p. 278-284Article in journal (Refereed)
    Abstract [en]

    Dementia is a devastating manifestation of Parkinson's disease (PD). This study investigates whether a common polymorphism in the PITX3 gene (rs2281983), which is of importance for the function of dopaminergic neurons, affects the risk of developing dementia in PD and whether it affects dopamine transporter (DAT) uptake. We PITX3 genotyped 133 patients with new-onset, idiopathic PD, participating in a population-based study in Sweden. Patients were followed prospectively during 6-11 years with extensive investigations, including neuropsychology and DAT-imaging with I-123 FP-CIT. The primary outcome was the incidence of PD dementia (PDD), diagnosed according to published criteria, studied by the Kaplan-Meier method and Cox proportional hazards. Performance in individual cognitive domains, the incidence of visual hallucinations, disease progression and striatal DAT uptake on imaging was also investigated. PD patients carrying the PITX3 C allele had an increased risk of developing PDD (hazard ratio: 2.87, 95% CI: 1.42-5.81, p = 0.003), compared to the PD patients homozygous for the T-allele. Furthermore, the PITX3 C allele carriers with PD had a poorer cognitive performance in the visuospatial domain (p < 0.001) and a higher incidence of visual hallucinations. A trend towards a lower striatal DAT uptake in the PITX3 C allele carriers was suggested, but could not be confirmed. Our results show that a common polymorphism in the PITX3 gene affects the risk of developing PDD and visuospatial dysfunction in idiopathic PD. If validated, these findings can provide new insights into the neurobiology and genetics of non-motor symptoms in PD.

  • 11.
    Bäckström, David
    et al.
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Eriksson Domellöf, Magdalena
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Granåsen, Gabriel
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Epidemiology and Global Health.
    Linder, Jan
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Mayans, Sofia
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Elgh, Eva
    Umeå University, Faculty of Social Sciences, Department of Psychology.
    Zetterberg, H.
    Blennow, K.
    Forsgren, Lars
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Polymorphisms in dopamine-associated genes and cognitive decline in Parkinson's disease2018In: Acta Neurologica Scandinavica, ISSN 0001-6314, E-ISSN 1600-0404, Vol. 137, no 1, p. 91-98Article in journal (Refereed)
    Abstract [en]

    Objectives: Cognitive decline is common in Parkinson's disease (PD), but the underlying mechanisms for this complication are incompletely understood. Genotypes affecting dopamine transmission may be of importance. This study investigates whether genotypes associated with reduced prefrontal dopaminergic tone and/or reduced dopamine D2-receptor availability (Catechol-O-methyltransferase [COMT] Val(158)Met genotype and DRD2 (CT)-T-957 genotype) affect the development of cognitive deficits in PD.

    Materials and methods: One hundred and 34 patients with idiopathic PD, participating in a regional, population-based study of incident parkinsonism, underwent genotyping. After extensive baseline investigations (including imaging and biomarker analyses), the patients were followed prospectively during 6-10 years with neuropsychological evaluations, covering six cognitive domains. Cognitive decline (defined as the incidence of either Parkinson's disease mild cognitive impairment [PD-MCI] or dementia [PDD], diagnosed according to published criteria and blinded to genotype) was studied as the primary outcome.

    Results: Both genotypes affected cognition, as shown by Cox proportional hazards models. While the COMT(158)Val/Val genotype conferred an increased risk of mild cognitive impairment in patients with normal cognition at baseline (hazard ratio: 2.13, P=.023), the DRD2(957)T/T genotype conferred an overall increased risk of PD dementia (hazard ratio: 3.22, P<.001). The poorer cognitive performance in DRD2(957)T/T carriers with PD occurred mainly in episodic memory and attention.

    Conclusions: The results favor the hypothesis that dopamine deficiency in PD not only relate to mild cognitive deficits in frontostriatal functions, but also to a decline in memory and attention. This could indicate that dopamine deficiency impairs a wide network of brain areas.

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  • 12.
    Bäckström, David
    et al.
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Granåsen, Gabriel
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Epidemiology and Global Health.
    Eriksson Domellöf, Magdalenax
    Umeå University, Faculty of Social Sciences, Department of Psychology. Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Linder, Jan
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Jakobson Mo, Susanna
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology. Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI).
    Riklund, Katrine
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology. Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI).
    Zetterberg, Henrik
    Blennow, Kaj
    Forsgren, Lars
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Early predictors of mortality in parkinsonism and Parkinson disease: A population-based study2018In: Neurology, ISSN 0028-3878, E-ISSN 1526-632X, Vol. 91, no 22, p. E2045-E2056Article in journal (Refereed)
    Abstract [en]

    Objective To examine mortality and associated risk factors, including possible effects of mild cognitive impairment, imaging, and CSF abnormalities, in a community-based population with incident parkinsonism and Parkinson disease. Methods One hundred eighty-two patients with new-onset, idiopathic parkinsonism were diagnosed from January 2004 through April 2009, in a catchment area of 142,000 inhabitants in Sweden. Patients were comprehensively investigated according to a multimodal research protocol and followed prospectively for up to 13.5 years. A total of 109 patients died. Mortality rates in the general Swedish population were used to calculate standardized mortality ratio and expected survival, and Cox proportional hazard models were used to investigate independent predictors of mortality. Results The standardized mortality ratio for all patients was 1.84 (95% confidence interval 1.50-2.22, p < 0.001). Patients with atypical parkinsonism (multiple system atrophy or progressive supranuclear palsy) had the highest mortality. In early Parkinson disease, a mild cognitive impairment diagnosis, freezing of gait, hyposmia, reduced dopamine transporter activity in the caudate, and elevated leukocytes in the CSF were significantly associated with shorter survival. Conclusion Although patients presenting with idiopathic parkinsonism have reduced survival, the survival is highly dependent on the type and characteristics of the parkinsonian disorder. Patients with Parkinson disease presenting with normal cognitive function seem to have a largely normal life expectancy. The finding of a subtle CSF leukocytosis in patients with Parkinson disease with short survival may have clinical implications.

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  • 13.
    Degerman, Sofie
    et al.
    Umeå University, Faculty of Medicine, Department of Medical Biosciences, Pathology.
    Domellöf, Magdalena
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Landfors, Mattias
    Umeå University, Faculty of Medicine, Department of Medical Biosciences, Pathology.
    Linder, Jan
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Lundin, Mathias
    Umeå University, Faculty of Social Sciences, Umeå School of Business and Economics (USBE), Statistics.
    Haraldsson, Susann
    Umeå University, Faculty of Medicine, Department of Medical Biosciences, Pathology.
    Elgh, Eva
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Psychiatry.
    Roos, Göran
    Umeå University, Faculty of Medicine, Department of Medical Biosciences, Pathology.
    Forsgren, Lars
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Long Leukocyte Telomere Length at Diagnosis Is a Risk Factor for Dementia Progression in Idiopathic Parkinsonism2014In: PLOS ONE, E-ISSN 1932-6203, Vol. 9, no 12, article id e113387Article in journal (Refereed)
    Abstract [en]

    Telomere length (TL) is regarded as a marker of cellular aging due to the gradual shortening by each cell division, but is influenced by a number of factors including oxidative stress and inflammation. Parkinson's disease and atypical forms of parkinsonism occur mainly in the elderly, with oxidative stress and inflammation in afflicted cells. In this study the relationship between blood TL and prognosis of 168 patients with idiopathic parkinsonism (136 Parkinson's disease [PD], 17 Progressive Supranuclear Palsy [PSP], and 15 Multiple System Atrophy [MSA]) and 30 controls was investigated. TL and motor and cognitive performance were assessed at baseline (diagnosis) and repeatedly up to three to five years follow up. No difference in TL between controls and patients was shown at baseline, nor any significant difference in TL stability or attrition during follow up. Interestingly, a significant relationship between TL at diagnosis and cognitive phenotype at follow up in PD and PSP patients was found, with longer mean TL at diagnosis in patients that developed dementia within three years.

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  • 14.
    Elgh, Eva
    et al.
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Geriatric Medicine.
    Domellöf, Magdalena
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Geriatric Medicine. Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Linder, Jan
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Edström, Mona
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Stenlund, Hans
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Epidemiology and Global Health.
    Forsgren, Lars
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Cognitive function in early Parkinson's disease: a population-based study2009In: European Journal of Neurology, ISSN 1351-5101, E-ISSN 1468-1331, Vol. 16, no 12, p. 1278-1284Article in journal (Refereed)
    Abstract [en]

    BACKGROUND AND PURPOSE: The study aims to describe the frequency, pattern and determinants of cognitive function in patients with newly diagnosed Parkinson's disease (PD); to compare patients with impaired cognition to patients with intact cognition; and to compare to matched healthy controls.

    METHODS: Patients were identified in a longitudinal population based study of idiopathic non-drug induced parkinsonism. Eighty-eight newly diagnosed patients with PD and no dementia were included during a four year period. The patients and 30 age- and sex-matched healthy control subjects underwent a comprehensive neuropsychological assessment.

    RESULTS: Patients performed significantly worse than healthy controls in a majority of neuropsychological tests. Test results in attention, psychomotor function, episodic memory (free recall), executive function and category fluency were significantly lower in the patient group. Comparison with normative data revealed that 30% of the patients had deficits in > or =1 cognitive domain (episodic memory, executive function and verbal function). Seventy per cent of the patients had normal performance. Unified Parkinson's Disease Rating Scale (UPDRS) III sub scores; speech, facial expression, rigidity and bradykinesia were significantly higher, and disease duration shorter amongst the cognitively impaired than amongst the cognitively intact patients. Tremor showed no difference. Education level was an independent predictor of dysfunction in patients with > or =2 cognitive domains affected.

    CONCLUSION: Cognitive dysfunction is common in untreated patients in early PD, affecting attention, psychomotor function, episodic memory, executive function and category fluency. Education level was an independent predictor of severe cognitive dysfunction.

  • 15. Hansson, Oskar
    et al.
    Janelidze, Shorena
    Hall, Sara
    Magdalinou, Nadia
    Lees, Andrew J.
    Andreasson, Ulf
    Norgren, Niklas
    Linder, Jan
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Forsgren, Lars
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Constantinescu, Radu
    Zetterberg, Henrik
    Blennow, Kaj
    Blood-based NfL: A biomarker for differential diagnosis of parkinsonian disorder2017In: Neurology, ISSN 0028-3878, E-ISSN 1526-632X, Vol. 88, no 10, p. 930-937Article in journal (Refereed)
    Abstract [en]

    Objective: To determine if blood neurofilament light chain (NfL) protein can discriminate between Parkinson disease (PD) and atypical parkinsonian disorders (APD) with equally high diagnostic accuracy as CSF NfL, and can therefore improve the diagnostic workup of parkinsonian disorders. Methods: The study included 3 independent prospective cohorts: the Lund (n 5 278) and London (n 5 117) cohorts, comprising healthy controls and patients with PD, progressive supranuclear palsy (PSP), corticobasal syndrome (CBS), and multiple system atrophy (MSA), as well as an early disease cohort (n 5 109) of patients with PD, PSP, MSA, or CBS with disease duration <= 3 years. Blood NfL concentration was measured using an ultrasensitive single molecule array (Simoa) method, and the diagnostic accuracy to distinguish PD from APD was investigated. Results: We found strong correlations between blood and CSF concentrations of NfL (p >= 0.73-0.84, p <= 0.001). Blood NfL was increased in patients with MSA, PSP, and CBS (i.e., all APD groups) when compared to patients with PD as well as healthy controls in all cohorts (p, 0.001). Furthermore, in the Lund cohort, blood NfL could accurately distinguish PD from APD (area under the curve [AUC] 0.91) with similar results in both the London cohort (AUC 0.85) and the early disease cohort (AUC 0.81). Conclusions: Quantification of blood NfL concentration can be used to distinguish PD from APD. Blood-based NfL might consequently be included in the diagnostic workup of patients with parkinsonian symptoms in both primary care and specialized clinics.

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  • 16.
    Heldestad, Victoria
    et al.
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neurophysiology.
    Linder, Jan
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Neurology.
    Sellersjö, Lisa
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neurophysiology.
    Nordh, Erik
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neurophysiology.
    Reproducibility and influence of test modality order on thermal perception and thermal pain thresholds in quantitative sensory testing2010In: Clinical Neurophysiology, ISSN 1388-2457, E-ISSN 1872-8952, Vol. 121, no 11, p. 1878-1885Article in journal (Refereed)
    Abstract [en]

    The findings show that QST with the MLI is a reliable tool for indirect evaluation of human small nerve fiber function.

  • 17.
    Håglin, Lena
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Family Medicine.
    Bäckman, L
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Family Medicine.
    Linder, Jan
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Forsgren, Lars
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Domellöf, Magdalena
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience. Umeå University, Faculty of Social Sciences, Department of Psychology.
    Early Recognition of Cognitive Ability and Nutritional Markers for Dementia in Parkinson’s Disease2018In: Journal of Aging Research & Clinical Practice, ISSN 2258-8094, Vol. 7, p. 156-162Article in journal (Refereed)
    Abstract [en]

    Background: Cognitive decline and dementia are common non-motor problems in Parkinson’s disease (PD). The underlying aetiology is multifaceted and both chronic and reversible causes for cognitive decline are likely to be present. Malnutrition is frequent in the Parkinson population, both early and late in the disease, and nutritional deficiencies could play a role in some cognitive deficits. Objectives: The objective is to study the association between nutritional status with focus on iron intake and homeostasis, mild cognitive impairment (MCI), and PD dementia (PDD). Setting and Participants: This study included 73 out of 145 patients with PD participating in a population-based study in northern Sweden. Measurements: Registration of nutritional status by laboratory analyses of blood plasma and neuropsychological assessments at time of diagnosis were performed. MCI and PDD were assessed yearly up to ten years after diagnosis. Mini Nutritional Assessments (Full-MNA score) and plasma variables detecting iron homeostasis were compared between patients with MCI and patients with normal cognition (NC). Motor severity was measured using the Unified Parkinson´s disease rating scale III, (UPDRS III) and Hoehn and Yahr (H&Y) staging scale. Cox proportional Hazard model were performed to see if any variables that differed between MCI and NC could predict PDD at follow-up. Results: Patients with MCI at time of diagnosis had lower levels of plasma iron (P-Fe) and albumin (P-Albumin) as well as a lower score on Full-MNA score. Dietary intake of iron was higher in patients with MCI than in patients with NC (p = 0.012). In logistic regression models adjusted for age, sex, and UPDRS III, lower levels of P-Fe (p = 0.025) and P-Albumin (p = 0.011) and higher dietary iron intake (p = 0.019) were associated with MCI at baseline. A Cox regression model with dementia as endpoint revealed that lower levels of P-Fe increase the risk of dementia at follow-up with adjustments for age, sex, UPDRS III, and MCI at baseline (HR 95% CI = 0.87 (0.78-0.98), p = 0.021). Conclusions: Low P-Fe was associated with cognitive disturbance at baseline and predicted dementia up to ten years after diagnosis in patients with PD. Low P-Albumin and malnutrition assessed with Full-MNA score were associated with MCI at baseline but did not predict dementia at follow-up.

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  • 18. Iqbal, Zafar
    et al.
    Pihlstrom, Lasse
    Rengmark, Aina
    Henriksen, Sandra Pilar
    Linder, Jan
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Forsgren, Lars
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Toft, Mathias
    Rare variants in dementia genes and Parkinson's disease2016In: European Journal of Human Genetics, ISSN 1018-4813, E-ISSN 1476-5438, Vol. 24, no 12, p. 1661-1662Article in journal (Refereed)
  • 19.
    Jakobson Mo, Susanna
    et al.
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology. Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI). Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Axelsson, Jan
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics. Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI).
    Jonasson, Lars
    Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI). Umeå University, Faculty of Medicine, Department of Integrative Medical Biology (IMB).
    Larsson, Anne
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics. Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI).
    Ögren, Mattias J.
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology. Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI).
    Ögren, Margareta
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology.
    Varrone, Andrea
    Eriksson, Linda
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Bäckström, David
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    af Bjerkén, Sara
    Umeå University, Faculty of Medicine, Department of Integrative Medical Biology (IMB). Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Linder, Jan
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience. Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI).
    Riklund, Katrine
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology. Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI).
    Dopamine transporter imaging with [18F]FE-PE2I PET and [123I]FP-CIT SPECT – a clinical comparison2018In: EJNMMI Research, E-ISSN 2191-219X, Vol. 8, article id 100Article in journal (Refereed)
    Abstract [en]

    Background: Dopamine transporter (DAT) imaging may be of diagnostic value in patients with clinically suspected parkinsonian disease. The purpose of this study was to compare the diagnostic performance of DAT imaging with positron emission computed tomography (PET), using the recently developed, highly DAT-selective radiopharmaceutical [18F]FE-PE2I (FE-PE2I), to the commercially available and frequently used method with [123I]FP-CIT (FP-CIT) single-photon emission computed tomography (SPECT) in early-stage idiopathic parkinsonian syndrome (PS).

    Methods: Twenty-two patients with a clinical de novo diagnosis of PS and 28 healthy controls (HC) participating in an on-going clinical trial of FE-PE2I were analyzed in this study. Within the trial protocol, participants are clinically reassessed 2 years after inclusion. A commercially available software was used for automatic calculation of FP-CIT-specific uptake ratio (SUR). MRI-based volumes of interest combined with threshold PET segmentation were used for FE-PE2I binding potential relative to non-displaceable binding (BPND) quantification and specific uptake value ratios (SUVR).

    Results: PET with FE-PE2I revealed significant differences between patients with a clinical de novo diagnosis of PS and healthy controls in striatal DAT availability (p < 0.001), with excellent accuracy of predicting dopaminergic deficit in early-stage PS. The effect sizes were calculated for FE-PE2I BPND (Glass’s Δ = 2.95), FE-PE2I SUVR (Glass’s Δ = 2.57), and FP-CIT SUR (Glass’s Δ = 2.29). The intraclass correlation (ICC) between FE-PE2I BPND FP-CIT SUR was high in the caudate (ICC = 0.923), putamen (ICC = 0.922), and striatum (ICC = 0.946), p < 0.001. Five of the 22 patients displayed preserved striatal DAT availability in the striatum with both methods. At follow-up, a non-PS clinical diagnosis was confirmed in three of these, while one was clinically diagnosed with corticobasal syndrome. In these patients, FE-PE2I binding was also normal in the substantia nigra (SN), while significantly reduced in the remaining patients. FE-PE2I measurement of the mean DAT availability in the putamen was strongly correlated with BPND in the SN (R = 0.816, p < 0.001). Olfaction and mean putamen DAT availability was correlated using both FE-PE2I BPND and FP-CIT SUR (R ≥ 0.616, p < 0.001).

    Conclusion: DAT imaging with FE-PE2I PET yields excellent basic diagnostic differentiation in early-stage PS, at least as good as FP-CIT SPECT.

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  • 20.
    Jakobson Mo, Susanna
    et al.
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology.
    Larsson, Anne
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics.
    Linder, Jan
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Birgander, Richard
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology.
    Edenbandt, Lars
    Göteborgs Universitet, Avdelningen för molekylär och klinisk medicin.
    Stenlund, Hans
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Epidemiology and Global Health.
    Forsgren, Lars
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Riklund, Katrine
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology.
    123I-FP-Cit and 123I-IBZM SPECT uptake in a prospective normal material analysed with two different semi-quantitative image evaluation tools2013In: Nuclear medicine communications, ISSN 0143-3636, E-ISSN 1473-5628, Vol. 34, no 10, p. 978-989Article in journal (Refereed)
    Abstract [en]

    Objective: The need for age-adjusted and/or sex-adjusted reference values in dopamine transporter (DAT) and dopamine D2 receptor (D2R) imaging with single-photon emission computed tomography (SPECT) in a longitudinal study of parkinsonian diseases was investigated. We used two different image evaluation tools with a cross-sectional and longitudinal statistical approach.

    Materials and methods: Baseline DAT and/or D2R SPECT were performed in 51 healthy controls (HC), age-matched to patients in an ongoing prospective study on idiopathic parkinsonism. Twenty-four HC were re-examined after 3 years and 21 HC were examined again after 5 years. SPECT was performed with I-123-FP-Cit and I-123-IBZM on a two-headed hybrid gamma camera. Regions of interest and volumes of interest (VOIs) were used for image evaluation. A cross-sectional and longitudinal statistical analysis was carried out.

    Results: Fewer sex-based differences and less age dependency were seen in DAT SPECT uptake ratios compared with D2R SPECT uptake ratios and when comparing uptake ratios obtained with regions of interest against those with VOIs. In the cross-sectional analysis, a significant age-dependent decline was seen in women in both DAT and D2R uptakes with the VOI method but not in men with either evaluation method. In the longitudinal dataset, both a slight decline and increase over time were seen in DAT uptake; however, a general pattern of decrease was seen in both men and women in D2R uptake.

    Conclusion: The choice of the image evaluation method can influence the pattern of sex-based and age-related differences. The results speak for the use of age-stratified reference values for women, in particular when using a VOI method.

  • 21.
    Jakobson Mo, Susanna
    et al.
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology.
    Linder, Jan
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Blomstedt, Patric
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Granåsen, Gabriel
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Epidemiology and Global Health.
    Forsgren, Lars
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Hariz, Marwan
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience. Unit of Functional Neurosurgery, UCL Institute of Neurology, London, UK.
    Long-term dopamine transporter imaging in Parkinson's disease treated with zona incerta stimulation2016In: Nuclear medicine communications, ISSN 0143-3636, E-ISSN 1473-5628, Vol. 37, no 5, p. 499-508Article in journal (Refereed)
    Abstract [en]

    Objective: The caudal zona incerta (cZI) is a promising, clinically beneficial target for deep brain stimulation (DBS) in Parkinson’s disease (PD). To assess whether DBS of the cZI affects the rate of dopamine terminal dysfunction, PD patients with and without DBS were followed prospectively with 123I FP-Cit single photon emission tomography from the first diagnosis and up to 8 years.

    Methods: Six patients underwent DBS of the cZI during the survey period. Twenty-two PD patients only on pharmacotherapy served as controls. 123I FP-Cit and clinical assessment were performed at baseline and after 1, 3 and 5 years in all patients. Ten patients also underwent a 123I FP-Cit after 8 years. Image data were evaluated semiquantitatively. Mixed-model analysis was used to assess the relative change in 123I FP-Cit uptake and comparison between surgically and conservatively treated PD patients.

    Results: The relative decrease in 123I FP-Cit uptake was more pronounced in DBS-treated patients than in controls in the more affected caudate (P=0.037) and putamen (P=0.013). The annual decrease rates were higher in the less affected than the more affected putamen, and were slightly greater in DBS-treated patients (4.8%, 95%confidence interval: 8.5–2.2%) than in controls (4.0%, 95% confidence interval: 5.1–3.1%).

    Conclusion: This long-term prospective study confirms that the underlying dopaminergic dysfunction continues despite clinical improvement in PD patients with DBS of the cZI. A slightly faster rate of decrease in 123I FP-Cit uptake in these patients compared with conservatively treated PD patients may reflect a more aggressive form of PD.

  • 22.
    Jakobson Mo, Susanna
    et al.
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology.
    Linder, Jan
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Forsgren, Lars
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Holmberg, Henrik
    Umeå University, Faculty of Social Sciences, Umeå School of Business and Economics (USBE), Statistics.
    Larsson, Anne
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics.
    Riklund, Katrine
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology.
    Pre- and postsynaptic dopamine SPECT in idiopathic parkinsonian diseases: a follow-up study2013In: BioMed Research International, ISSN 2314-6141, Vol. 2013, p. 143532-Article in journal (Refereed)
    Abstract [en]

    We prospectively evaluated the diagnostic contribution of 123I-FP-Cit (DAT) and 123I-IBZM (IBZM) SPECT in 29 patients with Parkinson’s disease (PD) (74.4 ± 4.2 years) and 28 patients with atypical parkinsonian diseases (APD) (74.3 ± 9.2 years). Twelve had multiple system atrophy (MSA) and 16 progressive supranuclear palsy (PSP). Sixteen age-matched healthy controls (HC) were included. DAT and IBZM SPECTs were made at baseline and after 1 year in all PD patients and in 20 (DAT) and 18 (IBZM) of the APD patients, and after 3 years in 22 (DAT) and 17 (IBZM) of the PD patients and in 10 (DAT) and 10 (IBZM) of the APD patients. The relative DAT uptake decrease was faster in PD and PSP than in HC and MSA. In PSP the DAT uptake was lower than in MSA after 1 year but not after 3 years. Baseline IBZM uptake was not significantly different between patients and HC or between PD and APD. One year after initiated dopaminergic treatment the mean IBZM uptake in the MSA patients remained high compared to PSP and after 3 years compared to PD, PSP, and HC.Thus, the pattern of uptake of these ligands over time may be of value in discriminating between these diagnoses.

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    Pre- and postsynaptic dopamine SPECT in idiopathic parkinsonian diseases: a follow-up study
  • 23.
    Jakobson Mo, Susanna
    et al.
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology.
    Linder, Jan
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Neurology.
    Forsgren, Lars
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Neurology.
    Larsson, Anne
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics.
    Johansson, Lennart
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics.
    Riklund, Katrine
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology.
    Pre- and postsynaptic dopamine SPECT in the early phase of idiopathic parkinsonism: a population-based study2010In: European Journal of Nuclear Medicine and Molecular Imaging, ISSN 1619-7070, E-ISSN 1619-7089, Vol. 37, no 11, p. 2154-2164Article in journal (Refereed)
    Abstract [en]

    PURPOSE: The aim of this study was to assess the diagnostic contribution of pre- and postsynaptic dopamine SPECT in drug-naïve patients with early idiopathic parkinsonism and to investigate possible differences between idiopathic Parkinson's disease (PD) and atypical parkinsonian syndromes (APS) and possible differences in motor subtypes of parkinsonism.

    METHODS: A group of 128 newly diagnosed idiopathic parkinsonian patients and 48 healthy controls was studied. Presynaptic baseline SPECT with (123)I-FP-CIT was performed in all patients and in 120 patients also a baseline postsynaptic SPECT with (123)I-IBZM. Clinical diagnoses were reassessed after 12 months.

    RESULTS: Presynaptic uptake in the putamen and caudate was significantly reduced in patients compared to controls. Presynaptic uptake ratios were not different between PD patients and patients with APS, and postsynaptic uptake in APS was not significantly reduced compared to PD or controls. In half of the APS patients both pre- and postsynaptic uptake ratios were reduced on the same side in the striatum. Impaired motor performance was associated with decreased presynaptic uptake in the putamen in PD. The postural instability and gait difficulty (PIGD) subtype of PD had lower presynaptic uptake ratios than patients with tremor-dominated (TD) symptoms.

    CONCLUSION: Not only presynaptic putamen uptake ratios, but also caudate ratios were reduced in a majority of the patients in our study. At baseline scan, i.e. in an early stage of the disease, the accuracy of excluding APS in the whole study population was 85% using a combination of pre- and postsynaptic SPECT. Already at baseline, lower presynaptic SPECT ratios were seen in PD with PIGD at onset compared to those with TD subtype.

  • 24.
    Jakobson Mo, Susanna
    et al.
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology.
    Linder, Jan
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Forsgren, Lars
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Riklund, Katrine
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology.
    Accuracy of Visual Assessment of Dopamine Transporter Imaging in Early Parkinsonism2015In: Movement Disorders Clinical Practice, E-ISSN 2330-1619, Vol. 2, no 1, p. 17-23Article in journal (Refereed)
    Abstract [en]

    Dopamine transporter (DaT) imaging may be supportive in the initial clinical diagnostic workup in patients with suspected parkinsonian diseases, given that the method has the potential to detect dopaminergic degeneration. We investigated the diagnostic accuracy of visual assessment of the initial DaT single-photon emission CT (DaT-SPECT) with 123I-FP-CIT in a large group of early-stage parkinsonian patients. After inclusion in a long-term multidisciplinary population-based prospective study, a baseline DaT-SPECT was done in 171 incidental, L-dopa-naïve, parkinsonian patients (102 men and 69 women) and 37 healthy controls (19 men and 18 women). The results of the DaT-SPECTs were linked to criteria-based clinical diagnoses, which were set after a mean follow-up of 4.6 (±1.7) years. The outcome of the visual assessment was also compared with that of a semiquantitative evaluation method using regions of interest to measure uptake ratios in the caudate and putamen. We found that visual assessment of DaT-SPECT in clinically diagnosed incidental Parkinson's disease patients had a sensitivity of 94% and a specificity of 92%, rendering a positive likelihood ratio of 11.75 and a negative likelihood ratio of 0.07. The proportion of false positives was 1.4% and false negatives 4.8% at baseline. These figures were comparable to those of the semiquantitative method. This study demonstrates that visual interpretation of presynaptic dopamine imaging with 123I-FP-CIT offers reliable support in the diagnostic procedure of early parkinsonian diseases.

  • 25.
    Karlsson, Fredrik
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Speech and Language Therapy.
    Blomstedt, Patric
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Olofsson, Katarina
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Otorhinolaryngology.
    Linder, Jan
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Nordh, Erik
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    van Doorn, Jan
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Speech and Language Therapy.
    Control of phonatory onset and offset in Parkinson patients following deep brain stimulation of the subthalamic nucleus and caudal Zona Incerta2012In: Parkinsonism & Related Disorders, ISSN 1353-8020, E-ISSN 1873-5126, Vol. 18, no 7, p. 824-827Article in journal (Refereed)
    Abstract [en]

    Laryngeal hypokinesia is a common symptom in Parkinson’s disease (PD) that affects quality of life. Deep brain stimulation (DBS) is well recognized as a complementary method for treatment of motor symptoms in PD but the outcomes on patients’ control over phonatory alternation have yet not been clearly elucidated. The present study examined the effect of subthalamic nucleus STN-DBS (n=8, aged 51-72 yrs; median=63 yrs) and caudal Zona incerta cZi-DBS (n=8,aged 49-71 yrs; median=61 yrs) on control of onset and offset of phonation in connected speech. The patients were evaluated in a preoperatively (Med ON, 1.5 times the ordinary Levodopa dose) and 12 months postoperatively (Med ON, ordinary Levodopa dose). The results provided evidence of a progressive reduction in the ability to manifest alternations between voicing and voiceless states in a reading task. Mean proportion produced with inappropriate voicing increased from 47.6% to 55.3% and from 62.9% to 68.6% of the total duration for the two groups of patients between Pre-op and Post-op, Stim OFF evaluations. The medial and final parts of the fricative were more affected than the initial part, indicating an increased voicing lead into the following vowel. We propose that this reduction in phonatory control is be due to either progression of the disease, an effect of reduced Levodopa dosage or a microlesional effect. Patients’ proficiency in alternating between voiced and voiceless states in connected speech remained unaffected by both STN-DBS and cZi-DBS.

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    PRD_1780
  • 26.
    Karlsson, Fredrik
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Speech and Language Therapy.
    Malinova, Elin
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Speech and Language Therapy.
    Olofsson, Katarina
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Otorhinolaryngology.
    Blomstedt, Patric
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Linder, Jan
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Nordh, Erik
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Voice Tremor Outcomes of Subthalamic Nucleus and Zona Incerta Deep Brain Stimulation in Patients With Parkinson Disease2019In: Journal of Voice, ISSN 0892-1997, E-ISSN 1873-4588, Vol. 33, no 4, p. 545-549Article in journal (Refereed)
    Abstract [en]

    Objectives: We aimed to study the effect of deep brain stimulation (DBS) in the subthalamic nucleus (STN) and caudal zona incerta (cZi) on level of perceived voice tremor in patients with Parkinson disease (PD).

    Study Design: This is a prospective nonrandomized design with consecutive patients.

    Methods: Perceived voice tremor was assessed in patients with PD having received either STN-DBS (8 patients, 5 bilateral and 3 unilateral, aged 43.1-73.6 years; median = 61.2 years) or cZi-DBS (14 bilateral patients, aged 39.0-71.9 years; median = 56.6 years) 12 months before the assessment. Sustained vowels that were produced OFF and ON stimulation (with simultaneous L-DOPA medication) were assessed perceptually in terms of voice tremor by two raters on a four-point rating scale. The assessments were repeated five times per sample and rated in a blinded and randomized procedure.

    Results: Three out of the 22 patients (13%) were concluded to have voice tremor OFF stimulation. Patients with PD with STN-DBS showed mild levels of perceived voice tremor OFF stimulation and a group level improvement. Patients with moderate/severe perceived voice tremor and cZi-DBS showed marked improvements, but there was no overall group effect. Six patients with cZi-DBS showed small increases in perceived voice tremor severity.

    Conclusions: STN-DBS decreased perceived voice tremor on a group level. cZi-DBS decreased perceived voice tremor in patients with PD with moderate to severe preoperative levels of the symptom.

  • 27.
    Karlsson, Fredrik
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Speech and Language Therapy.
    Olofsson, Katarina
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Otorhinolaryngology.
    Blomstedt, Patric
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Neurosurgery.
    Linder, Jan
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Neurology.
    Doorn, Jan van
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Speech and Language Therapy.
    Pitch variability in patients with Parkinson’s disease: effects of deep brain stimulation of caudal zona incerta and subthalamic nucleus2013In: Journal of Speech, Language and Hearing Research, ISSN 1092-4388, E-ISSN 1558-9102, Vol. 56, no 1, p. 150-158Article in journal (Refereed)
    Abstract [en]

    Objective The purpose of the present study was to examine the effect of deep brain stimulation (DBS) of the subthalamic nucleus (STN) and the caudal zona incerta (cZi) pitch characteristics of con- nected speech in patients with Parkinson’s disease (PD).

    Methods Sixteen patients were evaluated preoperatively and 12 months after DBS surgery. Eight pa- tients were implanted in the STN (aged 51-72 yrs; xC=63 yrs). Six received bilateral implanta- tion and two unilateral (left) implantation. Eight patients were bilaterally implanted in the cZi (aged 49-71 yrs; xC=60.8 yrs). Preoperative assessments were made after an L-Dopa challenge (approximately 1.5 times the ordinary dose). All postoperative examinations were made off and on stimulation, with a clinically optimized dose of L-dopa. Measurements of pitch range and var- iability were obtained from each utterance in a recorded read speech passage.

    Results Pitch range and coefficient of variation showed an increase in patients under STN-DBS. Patients under cZi-DBS showed no significant effects of treatment on investigated pitch properties.

    Conclusions STN-DBS was shown to increase pitch variation and range. The results provided no evidence of cZi-DBS having a beneficial effect on PD patients’ pitch variability. 

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    Pitch variability in patients with Parkinson’s disease:
  • 28.
    Karlsson, Fredrik
    et al.
    Umeå University, Faculty of Arts, Department of language studies. Umeå University, Faculty of Medicine, Department of Clinical Sciences, Speech and Language Therapy.
    Olofsson, Katarina
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Otorhinolaryngology.
    Blomstedt, Patric
    Linder, Jan
    Nordh, Erik
    van Doorn, Jan
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Speech and Language Therapy.
    Articulatory closure proficiency in Parkinson's disease patients following deep brain stimulation of the subthalamic nucleus and caudal zona incerta.2014In: Journal of Speech, Language and Hearing Research, ISSN 1092-4388, E-ISSN 1558-9102, Vol. 57, p. 1178-1190Article in journal (Refereed)
    Abstract [en]

    OBJECTIVE

    The present study aimed at comparing the effects of deep brain stimulation (DBS) treatment of the subthalamic nucleus (STN) and the caudal zona incerta (cZi) on Parkinson's disease patients' proficiency in achieving oral closure and release during plosive production. METHODS Nineteen patients were evaluated preoperatively and 12 months after DBS surgery. Nine patients were implanted in the STN, seven bilaterally and two unilaterally (left). Ten were bilaterally implanted in the cZi. Postoperative examinations were made off and on stimulation. All patients received simultaneous L-dopa treatment in all conditions. For a series of plosives extracted from a reading passage, absolute and relative measures of duration of frication and amplitude of plosive release were compared between conditions within each treatment group. RESULTS Relative duration of frication increased in voiceless plosives in the on stimulation condition in cZi patients. Similar trends were observed across the data set. Duration of pre-release frication and the release peak prominence increased in voiceless plosives on stimulation for both groups. CONCLUSIONS The increased release prominence suggests that patients achieved a stronger closure gesture due to DBS, but that the increased energy available resulted in increased frication.

  • 29.
    Karlsson, Fredrik
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Speech and Language Therapy.
    Unger, Elin
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Speech and Language Therapy.
    Wahlgren, Sofia
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Speech and Language Therapy.
    Blomstedt, Patric
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Linder, Jan
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Nordh, Erik
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Zafar, Hamayun
    Umeå University, Faculty of Medicine, Department of Odontology, Clinical Oral Physiology.
    Doorn, Jan van
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Speech and Language Therapy.
    Deep brain stimulation of caudal zona incerta and subthalamic nucleus in patients with Parkinson’s disease: effects on diadochokinetic rate2011In: Parkinson's Disease, ISSN 2090-8083, E-ISSN 2042-0080, Vol. 2011, p. 605607-Article in journal (Refereed)
    Abstract [en]

    The hypokinetic dysarthria observed in Parkinson's disease (PD) affects the range, speed, and accuracy of articulatory gestures in patients, reducing the perceived quality of speech acoustic output in continuous speech. Deep brain stimulation (DBS) of the subthalamic nucleus (STN-DBS) and of the caudal zona incerta (cZi-DBS) are current surgical treatment options for PD. This study aimed at investigating the outcome of STN-DBS (7 patients) and cZi-DBS (7 patients) in two articulatory diadochokinesis tasks (AMR and SMR) using measurements of articulation rate and quality of the plosive consonants (using the percent measurable VOT metric). The results indicate that patients receiving STN-DBS increased in articulation rate in the Stim-ON condition in the AMR task only, with no effect on production quality. Patients receiving cZi-DBS decreased in articulation rate in the Stim-ON condition and further showed a reduction in production quality. The data therefore suggest that cZi-DBS is more detrimental for extended articulatory movements than STN-DBS.

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  • 30. Khoo, Sok Kean
    et al.
    Petillo, David
    Kang, Un Jung
    Resau, James H.
    Berryhill, Brian
    Linder, Jan
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Forsgren, Lars
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Neuman, Leslie A.
    Tan, Aik Choon
    Plasma-Based Circulating MicroRNA Biomarkers for Parkinson's Disease2012In: Journal of Parkinson's Disease, ISSN 1877-7171, Vol. 2, no 4, p. 321-331Article in journal (Refereed)
    Abstract [en]

    Background: The current "gold-standard" for Parkinson's disease (PD) diagnosis is based primarily on subjective clinical rating scales related with motor features. Molecular biomarkers that are objective and quantifiable remain attractive as clinical tools to detect PD prior to its motor onsets.

    Objective: Here, we aimed to identify, develop, and validate plasma-based circulating microRNA (miRNAs) as biomarkers for PD.

    Methods: Global miRNA expressions were acquired from a discovery set of 32 PD/32 controls using microarrays. k-Top Scoring Pairs (k-TSP) algorithm and significance analysis of microarrays (SAM) were applied to obtain comprehensive panels of PD-predictive biomarkers. TaqMan miRNA-specific real-time PCR assays were performed to validate the microarray data and to evaluate the biomarker performance using a new replication set of 42 PD/30 controls. Data was analyzed in a paired PD-control fashion. The validation set was composed of 30 PD, 5 progressive supranuclear palsy, and 4 multiple system atrophy samples from a new clinical site.

    Results: We identified 9 pairs of PD-predictive classifiers using k-TSP analysis and 13 most differentially-expressed miRNAs by SAM. A combination of both data sets produced a panel of PD-predictive biomarkers: k-TSP1 (miR-1826/miR-450b-3p), miR-626, and miR-505, and achieved the highest predictive power of 91% sensitivity, 100% specificity, 100% positive predicted value, and 88% negative predicted value in the replication set. However, low predictive values were shown in the validation set.

    Conclusions: This proof-of-concept study demonstrates the feasibility of using plasma-based circulating miRNAs as biomarkers for neurodegenerative disorders such as PD and shows the challenges of molecular biomarker research using samples from multiple clinical sites.

  • 31.
    Kulneff, Linda
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Speech and Language Therapy.
    Sundstedt, Stina
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Speech and Language Therapy.
    Olofsson, Katarina
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Otorhinolaryngology.
    van Doorn, Jan
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Speech and Language Therapy.
    Linder, Jan
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Neurology.
    Nordh, Erik
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neurophysiology.
    Blomstedt, Patric
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Neurosurgery.
    Deep brain stimulation: effects on swallowing function in Parkinson's disease2013In: Acta Neurologica Scandinavica, ISSN 0001-6314, E-ISSN 1600-0404, Vol. 127, no 5, p. 329-336Article in journal (Refereed)
    Abstract [en]

    Objective: In patients with Parkinson’s disease (PD), deep brainstimulation of the subthalamic nucleus (STN DBS) is well recognizedin improving limb function, but the outcome on swallowing functionhas rarely been studied. The aim of this work was to evaluate theeffect of STN DBS on pharyngeal swallowing function in patientswith PD using self-estimation and fiberoptic endoscopic evaluation ofswallowing.

    Methods: Eleven patients (aged 41–72, median 61 years)were evaluated preoperatively and at 6 and 12 months after STN DBSsurgery. All patients were evaluated with self-estimation on a visualanalogue scale, and eight of them with a fiberoptic endoscopicexamination with a predefined swallowing protocol includingRosenbek’s Penetration-Aspiration Scale, Secretion Severity Scale,preswallow spillage, pharyngeal residue, and pharyngeal clearance.

    Results: The self-assessments of swallowing function revealed asubjective improvement with STN DBS stimulation, whereas the datafrom the swallowing protocol did not show any significant effect ofthe STN DBS treatment itself. The prevalence of aspiration was notaffected by the surgery.

    Conclusions: The results show thatswallowing function was not negatively affected by STN DBS and therisk of aspiration did not increase. Self-estimation of swallowingfunction showed a subjective improvement due to stimulation.

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  • 32. Lill, Christina M.
    et al.
    Rengmark, Aina
    Pihlstrom, Lasse
    Fogh, Isabella
    Shatunov, Aleksey
    Sleiman, Patrick M.
    Wang, Li-San
    Liu, Tian
    Lassen, Christina F.
    Meissner, Esther
    Alexopoulos, Panos
    Calvo, Andrea
    Chio, Adriano
    Dizdar, Nil
    Faltraco, Frank
    Forsgren, Lars
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Kirchheiner, Julia
    Kurz, Alexander
    Larsen, Jan P.
    Liebsch, Maria
    Linder, Jan
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Morrison, Karen E.
    Nissbrandt, Hans
    Otto, Markus
    Pahnke, Jens
    Partch, Amanda
    Restagno, Gabriella
    Rujescu, Dan
    Schnack, Cathrin
    Shaw, Christopher E.
    Shaw, Pamela J.
    Tumani, Hayrettin
    Tysnes, Ole-Bjorn
    Valladares, Otto
    Silani, Vincenzo
    van den Berg, Leonard H.
    van Rheenen, Wouter
    Veldink, Jan H.
    Lindenberger, Ulman
    Steinhagen-Thiessen, Elisabeth
    Teipel, Stefan
    Perneczky, Robert
    Hakonarson, Hakon
    Hampel, Harald
    von Arnim, Christine A. F.
    Olsen, Jorgen H.
    Van Deerlin, Vivianna M.
    Al-Chalabi, Ammar
    Toft, Mathias
    Ritz, Beate
    Bertram, Lars
    The role of TREM2 R47H as a risk factor for Alzheimer's disease, frontotemporal lobar degeneration, amyotrophic lateral sclerosis, and Parkinson's disease2015In: Alzheimer's & Dementia: Journal of the Alzheimer's Association, ISSN 1552-5260, E-ISSN 1552-5279, Vol. 11, no 12, p. 1407-1416Article in journal (Refereed)
    Abstract [en]

    A rare variant in TREM2 (p.R47H, rs75932628) was recently reported to increase the risk of Alzheimer's disease (AD) and, subsequently, other neurodegenerative diseases, i.e. frontotemporal lobar degeneration (FTLD), amyotrophic lateral sclerosis (ALS), and Parkinson's disease (PD). Here we comprehensively assessed TREM2 rs75932628 for association with these diseases in a total of 19,940 previously untyped subjects of European descent. These data were combined with those from 28 published data sets by meta-analysis. Furthermore, we tested whether rs75932628 shows association with amyloid beta (Ab42) and total-tau protein levels in the cerebrospinal fluid (CSF) of 828 individuals with AD or mild cognitive impairment. Our data show that rs75932628 is highly significantly associated with the risk of AD across 24,086 AD cases and 148,993 controls of European descent (odds ratio or OR = 2.71, P = 4.67 x 10(-25)). No consistent evidence for association was found between this marker and the risk of FTLD (OR = 2.24, P = .0113 across 2673 cases/9283 controls), PD (OR 5 1.36, P = .0767 across 8311 cases/79,938 controls) and ALS (OR 5 1.41, P = .198 across 5544 cases/7072 controls). Furthermore, carriers of the rs75932628 risk allele showed significantly increased levels of CSF-total-tau (P = .0110) but not Ab42 suggesting that TREM2's role in AD may involve tau dysfunction. (C) 2015 The Alzheimer's Association.

  • 33.
    Linder, Jan
    Umeå University, Faculty of Medicine, Department of Radiation Sciences. Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Idiopathic parkinsonism: epidemiology and clinical characteristics of a population-based incidence cohort2012Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Background: Idiopathic parkinsonism is a neurodegenerative syndrome of unknown cause and includes Parkinson’s disease (PD) and atypical parkinsonian disorders. The atypical parkinsonian disorders are: Multiple system atrophy (MSA), progressive supranuclear palsy (PSP) and corticobasal degeneration (CBD). The incidence rates of these diseases in Sweden are largely unknown. The diagnosis of each disease relies mainly on clinical examination although several imaging and laboratory parameters may show changes. A diagnosis based on clinical examination is especially difficult early in the course of each disease; diagnosis is easier later on when disease-charactersistic signs have evolved and become more prominent. However, even in later stages it is not uncommon that patients are misdiagnosed. PD can be divided into subgroups based on the main clinical symptoms, i. e. tremor dominant, postural instability and gait difficulty (PIGD), and indeterminate. The PIGD subtype has worse prognosis including higher risk of dementia. The aims were to study the incidence of idiopathic parkinsonism and the different specific parkinsonian disorders in the Umeåregion and to investigate the patients early in the course of the disease with brainmagnetic resonance tomography (MRI), external anal sphincterelectromyography (EAS-EMG) and oculomotor examination. Can these methods improve the differential diagnostic work-up and/or differentiate between the subtypes of PD?

    Methods: We examined all patients in our catchment area (142,000 inhabitants) who were referred to us due to a suspected parkinsonian syndrome. Our clinic is the only clinic in the area receiving referrals regarding movement disorders. During the period (January 1, 2004 through April 30,2009) 190 patients fulfilled the inclusion criteria and were included in the study. Healthy volunteers served as controls. 

    Results: Incidence: We found the highest incidences reported in the literature: PD (22.5/100,000/year), MSA(2.4/100,000/year), and PSP (1.2/100,000/year). No CBD patients were encountered. Brain MRI: Degenerative changes were common both in controls and PD. There were no differences between the PD subtypes. EAS-EMG: Pathological changes in EAS-EMG examination were common in PD, MSA and PSP. It was not possible to separate PD, MSA and PSP by the EAS-EMG examination. Oculomotor examination: Pathological results were common in all diagnosis groups compared to controls. It was not possible to separate PD, MSA and PSP or the PD subtypes with the help of oculomotor examination.

    Conclusions: The incidences of idiopathic parkinsonism, PD, MSA and PSP were higher than previously reported in the literature. It is not clear weather this is due to a true higher incidence in the Umeå region or a more effective casefinding than in other studies. MRI, EAS-EMG and oculomotor examination could not contribute to the differential diagnostic work-up between PD, MSA and PSP nor differentiate between PD subtypes early in the course of the disease.

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  • 34.
    Linder, Jan
    et al.
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Neurology.
    Birgander, Richard
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology.
    Olsson, Ingegerd
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology.
    Riklund, Katrine
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology.
    Larsson, Ann-Katrine
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology.
    Edström, Mona
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Neurology.
    Stenlund, Hans
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Epidemiology and Global Health.
    Forsgren, Lars
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Neurology.
    Degenerative changes were common in brain magnetic resonance imaging in patients with newly diagnosed Parkinson's disease in a population-based cohort2009In: Journal of Neurology, ISSN 0340-5354, E-ISSN 1432-1459, Vol. 256, no 10, p. 1671-1680Article in journal (Refereed)
    Abstract [en]

    The aim of this study was to investigate newly diagnosed patients with Parkinson's disease (PD) with structural magnetic resonance imaging (MRI), to compare them with healthy controls, to relate the findings to clinical subtypes - tremor dominant (TD) or postural instability and gait difficulty (PIGD) - and to investigate the relationship between both the duration from onset of symptoms to diagnosis and the severity of symptoms and the MRI findings. Patients with a definite PD diagnosis were compared to patients with a probable PD diagnosis. We hypothesized that the PIGD subtype, the probable PD group, a greater symptom severity and a longer symptom duration would all be associated with more frequent pathological findings. Sixty-six PD patients were included and examined with MRI, 35 with the PIGD subtype and 23 with the TD subtype. Fifty-three had definite PD and 13 probable PD. Thirty healthy individuals, matched for age and sex, served as controls. Degenerative changes in the cerebellar cortex and the superior cerebellar peduncle were significantly more common in the probable PD group than in the controls, suggesting the possibility of an emerging atypical parkinsonian disorder. No significant MRI differences were found between definite PD and controls, between definite PD and probable PD, nor between PIGD and TD. No significant associations were found between duration to diagnosis and MRI results, nor between severity of symptoms and MRI results. Thus, although pathological MRI findings were common they can not be used to separate subgroups of PD in newly diagnosed patients.

  • 35.
    Linder, Jan
    et al.
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Libelius, Rolf
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Nordh, Erik
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Holmberg, Björn
    Institute of Neuroscience and Physiology/Neurology Göteborg University, Göteborg, Sweden..
    Stenlund, Hans
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Epidemiology and Global Health.
    Forsgren, Lars
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Anal sphincter electromyography in patients with newly diagnosed idiopathic parkinsonism2012In: Acta Neurologica Scandinavica, ISSN 0001-6314, E-ISSN 1600-0404, Vol. 126, no 4, p. 248-255Article in journal (Refereed)
    Abstract [en]

    Objectives The differential diagnosis of patients with idiopathic parkinsonism is difficult, especially early in the course of the disease. External anal sphincter electromyography has been reported to be of value in the differential diagnosis between Parkinson’s disease and multiple system atrophy. Patients with multiple system atrophy are reported to have pathological external anal sphincter electromyography and patients with Parkinson’s disease are reported to have significantly less pathological external anal sphincter electromyography results. Comparisons between patients with parkinsonian disorders have usually been made many years into the disease, and thus it is largely unknown if the results of external anal sphincter electromyography can be used to distinguish the different diagnoses in the early phase of the disease.

    Material and methods We investigated 148 newly diagnosed patients with idiopathic parkinsonism from a population-based incidence cohort (100 definite Parkinson’s disease, 21 probable Parkinson’s disease, 16 multiple system atrophy, eleven progressive supranuclear palsy, and 40 controls) with external anal sphincter electromyography within three months of their first visit and, in the majority of patients, before start of treatment with dopaminergic drugs. The clinical diagnoses were made using established clinical diagnostic criteria after a median follow-up of three years.

    Results All patient groups had more pathological external anal sphincter electromyography results than controls. No external anal sphincter electromyography differences were found between the patient groups, especially not between Parkinson’s disease and multiple system atrophy.

    Conclusions External anal sphincter electromyography examination cannot separate the different parkinsonian subgroups from each other in early course of the diseases.

  • 36.
    Linder, Jan
    et al.
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Neurology.
    Stenlund, Hans
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Epidemiology and Global Health.
    Forsgren, Lars
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Neurology.
    Incidence of Parkinson's disease and parkinsonism in northern Sweden: a population-based study2010In: Movement Disorders, ISSN 0885-3185, E-ISSN 1531-8257, Vol. 25, no 3, p. 341-348Article in journal (Refereed)
    Abstract [en]

    The differential diagnosis of parkinsonian disorders is difficult, especially early in the course of the diseases. The clinical subtypes of Parkinson's disease (PD) have not so far been described in newly diagnosed patients. We present a prospective incidence cohort study of patients with idiopathic parkinsonian syndromes in the Umeå region in northern Sweden identified over a 4-year period. The clinical diagnoses were re-evaluated at follow-up visits at 12 months. We found 138 patients with parkinsonism: 112 PD, 12 multiple system atrophy with predominant parkinsonism (MSA-P), six progressive supranuclear palsy (PSP) and eight unclassifiable patients. The crude incidences for all age ranges per 100,000 were: PD 19.7 (95% confidence interval 16.1-23.3); MSA-P 2.1 (1.1-3.7); PSP 1.1 (0.4-2.4); idiopathic parkinsonism 24.3 (20.2-28.4). Age-standardized to the average Swedish population 2004-2007: PD 22.5 (18.3-26.7); MSA-P 2.4 (1.2-4.2); PSP 1.2 (0.4-2.6); idiopathic parkinsonism 27.5 (22.9-32.1). The crude annual incidence rate for PD, with exclusion of patients with normal dopamine receptor uptake (FP-CIT-SPECT), was 18.8 per 100,000 (95% confidence interval 15.2-22.4), age-adjusted to the average Swedish population 2004 to 2007: 21.5 (17.4-25.6). The incidence rates did not differ significantly between men and women. The cumulative incidence of PD up to 89 years of age was for men 3.4%, for women 2.6%, and for both sexes combined 2.9%. The annual incidence rates found for PD, idiopathic parkinsonism, MSA-P and PSP are among the highest reported.

  • 37.
    Linder, Jan
    et al.
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Wenngren, Britt-Inger
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Otorhinolaryngology.
    Stenlund, Hans
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Epidemiology and Global Health.
    Forsgren, Lars
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Impaired oculomotor function in a community-based patient population with newly diagnosed idiopathic parkinsonism2012In: Journal of Neurology, ISSN 0340-5354, E-ISSN 1432-1459, Vol. 259, no 6, p. 1206-1214Article in journal (Refereed)
    Abstract [en]

    The differential diagnosis of idiopathic parkinsonism can be very challenging, especially early in the course of the disease. Oculomotor function has been reported to differ between the diseases constituting idiopathic parkinsonism. A detailed examination of the oculomotor functions could thus possibly be useful in the early differential diagnostic procedure. Oculomotor function could also differ between subgroups of patients with Parkinson's disease (PD). We examined the oculomotor function in a population-based incidence cohort with newly diagnosed idiopathic parkinsonism and 38 controls. We examined 135 patients with parkinsonism 105 PD, 11 progressive supranuclear palsy (PSP), and 19 multiple system atrophy with predominant parkinsonism (MSA-P)] within 3 months of their first visit to our clinic and before initiation of dopaminergic medication. The oculomotor measurements were repeated after 12 months. The clinical diagnosis was that of the latest clinical follow-up (median follow-up was 3 years). All patients were examined with (123)I-N-(omega)-fluoropropyl-2-β-carbomethoxy-3-β-(4-iodophenyl) nortropane single-photon emission computed tomography (FP-CIT SPECT), and only patients with pathological uptake of the ligand were included. Pathological changes in the oculomotor function were found in all patient groups compared to controls at the baseline examination. In PD, there were correlations between total axial motor scores and vertical saccade velocity and precision, horizontal saccade velocity and precision, and smooth pursuit gain at 20 and 30°/s. Oculomotor test results could not separate the different forms of idiopathic parkinsonism in the early phase from each other. Few changes in the oculomotor functions were observed between the baseline and the 12-month follow-up examinations. No correlations were found between the oculomotor measurements and disease severity or duration.

  • 38.
    Lizana, Helena
    et al.
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics.
    Johansson, Lennart
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics.
    Axelsson, Jan
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics.
    Larsson, Anne
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics.
    Ögren, Mattias
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology.
    Linder, Jan
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Halldin, Christer
    Varrone, Andrea
    Jakobson Mo, Susanna
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology.
    Whole-Body Biodistribution and Dosimetry of the Dopamine Transporter Radioligand 18F-FE-PE2I in Human Subjects2018In: Journal of Nuclear Medicine, ISSN 0161-5505, E-ISSN 1535-5667, Vol. 59, no 8, p. 1275-1280Article in journal (Refereed)
    Abstract [en]

    F-18-(E)-N-(3-iodoprop-2-enyl)-2 beta-carbofluoroethoxy-3 beta-(4'-methylphenyl) nortropane (F-18-FE-PE2I) was recently developed and has shown adequate affinity and high selectivity for the dopamine transporter (DAT). Previous studies have shown promising results for F-18-FE-PE2I as a suitable radioligand for DAT imaging. In this study, we investigated the whole-body biodistribution and dosimetry of F-18-FE-PE2I in healthy volunteers to support its utility as a suitable PET imaging agent for the DAT. Methods: Five healthy volunteers were given a mean activity of 2.5 MBq/kg, and 3 PET scans, head to thigh, were performed immediately after injection followed by 4 whole-body PET/CT scans between 0.5 and 6 h after injection. Blood samples were drawn in connection with the whole-body scans, and all urine was collected until 6 h after injection. Volumes of interest were delineated around 17 organs on all images, and the areas under the time-activity curves were calculated to obtain the total number of decays in the organs. The absorbed doses to organs and the effective dose were calculated using the software IDAC. Results: The highest activity concentration was observed in the liver (0.9%-1.2% injected activity/100 g) up to 30 min after injection. At later time points, the highest concentration was seen in the gallbladder (1.1%-0.1% injected activity/100 g). The activity excreted with urine ranged between 23% and 34%, with a mean of 28%. The urinary bladder received the highest absorbed dose (119 mu Gy/MBq), followed by the liver (46 mu Gy/MBq). The effective dose was 23 mu Sv/MBq (range, 19-28 mu Sv/MBq), resulting in an effective dose of 4.6 mSv for an administered activity of 200 MBq. Conclusion: The effective dose is within the same order of magnitude as other commonly used PET imaging agents as well as DAT agents. The reasonable effective dose, together with the previously reported favorable characteristics for DAT imaging and quantification, indicates that F-18-FE-PE2I is a suitable radioligand for DAT imaging.

  • 39.
    Louise, Johansson
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Speech and Language Therapy.
    Sofia, Möller
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Speech and Language Therapy.
    Olofsson, Katarina
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Otorhinolaryngology.
    Linder, Jan
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Neurology.
    Nordh, Erik
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Neurology. Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neurophysiology.
    Blomstedt, Patric
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Neurosurgery.
    Doorn, Jan van
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Speech and Language Therapy.
    Karlsson, Fredrik
    Umeå University, Faculty of Arts, Department of language studies. Umeå University, Faculty of Medicine, Department of Clinical Sciences, Speech and Language Therapy.
    Word-level intelligibility after caudal zona incerta stimulation for Parkinson’s disease2014In: Acta Neurologica Scandinavica, ISSN 0001-6314, E-ISSN 1600-0404, Vol. 130, no 1, p. 27-33Article in journal (Refereed)
    Abstract [en]

    Objectives – To investigate the effect of caudal zona incerta-deep brain stimulation (cZi-DBS) on word-level speech intelligibility in patients with Parkinson’s disease, under both an optimal listening condition and a simulated more naturalistic listening condition.

    Materials and methods – Spoken single words were extracted from read samples collected from 10 bilaterally implanted patients with PD pre- and post-cZi-DBS. Intelligibility was assessed through a transcription task performed by 32 naive listeners under two listening conditions: (i) with low-amplitude conversational speech added as background and (ii) with no added background noise. The listeners′ responses were scored in terms of agreement with the intended words.

    Results – Post-operatively, the total intelligibility score was significantly lower when cZi stimulation was switched on compared with off, for both listening conditions (with and without added background noise). Intelligibility was also significantly lower on stimulation compared with preoperative recordings, but only when assessed in the listening condition without background noise. The listening condition with added background noise resulted in significantly lower intelligibility scores compared with the no added noise condition for all stimulation conditions.

    Conclusions – The results of this study indicate that cZi-DBS in patients with PD can be detrimental to word-level speech intelligibility. 

  • 40.
    Loutfi, Ghada
    et al.
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Blomstedt, Patric
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Linder, Jan
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Hariz, Marwan
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Pallidal deep brain stimulation in the treatment of Huntington's chorea2014In: European Journal of Neurology, ISSN 1351-5101, E-ISSN 1468-1331, Vol. 21, p. 125-125Article in journal (Other academic)
  • 41.
    Loutfi, Ghada
    et al.
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Linder, Jan
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Hariz, Gun-Marie
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Occupational Therapy.
    Hariz, Marwan
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience. Unit of Functional Neurosurgery, UCL Institute of Neurology, Queen Square, London, United Kingdom.
    Blomstedt, Patric
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Pallidal Deep Brain Stimulation in the Treatment of Huntington’s Chorea2014In: Brain Disorders & Therapy, ISSN 2168-975X, Vol. 3, no 4Article in journal (Refereed)
    Abstract [en]

    Despite the success of deep brain stimulation (DBS) in various movement disorders, its use in Huntington´s Disease (HD) has been limited. So far, promising results of pallidal DBS have been reported in 7 patients with HD. We performed bilateral pallidal DBS in a 59 year old woman with HD since 12 years and severe motor symptoms. At the evaluation after 12 months the effect was deemed satisfactory mainly concerning the patient’s choreatic symptoms. However, the improvement according to the unified Huntington’s disease rating scale was modest, with a score reduction from 92 to 81.

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  • 42.
    Lunde, Kristin Aaser
    et al.
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Chung, Janete
    Dalen, Ingvild
    Pedersen, Kenn Freddy
    Linder, Jan
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Domellöf, Magdalena E.
    Umeå University, Faculty of Social Sciences, Department of Psychology. Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Elgh, Eva
    Umeå University, Faculty of Social Sciences, Department of Psychology.
    Macleod, Agnus D
    Tzoulis, Charalampos
    Larsen, Jan-Petter
    Tysnen, Ole-Bjørn
    Forsgren, Lars
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Counsell, Carl E.
    Alves, Guido
    Maple-Grødem, Jodi
    Association of glucocerebrosidase polymorphisms and mutations with dementia in incident Parkinson's disease2018In: Alzheimer's & Dementia: Journal of the Alzheimer's Association, ISSN 1552-5260, E-ISSN 1552-5279, ISSN 1552-5260, Vol. 14, no 10, p. 1293-1301Article in journal (Refereed)
    Abstract [en]

    Introduction

    Both polymorphisms and mutations in glucocerebrosidase (GBA) may influence the development of dementia in patients with Parkinson's disease.

    Methods

    Four hundred forty-two patients and 419 controls were followed for 7 years. Dementia was diagnosed using established criteria. Participants were analyzed for GBA genetic variants, including E326K, T369M, and L444P. Associations between GBA carrier status and dementia were assessed with Cox survival analysis.

    Results

    A total of 12.0% of patients with Parkinson's disease carried a GBA variant, and nearly half (22/53) of them progressed to dementia during follow-up. Carriers of deleterious GBA mutations (adjusted hazard ratio 3.81, 95% confidence interval 1.35 to 10.72; P = .011) or polymorphisms (adjusted hazard ratio 1.79; 95% confidence interval 1.07 to 3.00; P = .028) progressed to dementia more rapidly than noncarriers.

    Discussion

    GBA variants are of great clinical relevance for the development of dementia in Parkinson's disease, especially due to the relatively higher frequency of these alleles compared with other risk alleles.

  • 43.
    Lundgren, Sofie
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Speech and Language Therapy.
    Saeys, Thomas
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Speech and Language Therapy.
    Karlsson, Fredrik
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Speech and Language Therapy.
    Olofsson, Katarina
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Otorhinolaryngology.
    Blomstedt, Patric
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Linder, Jan
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Nordh, Erik
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Zafar, Hamayun
    Umeå University, Faculty of Medicine, Department of Odontology, Clinical Oral Physiology.
    Doorn, Jan van
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Speech and Language Therapy.
    Deep brain stimulation of caudal zona incerta and subthalamic nucleus in patients with Parkinson’s disease: effects on voice intensity2011In: Parkinson's Disease, ISSN 2090-8083, E-ISSN 2042-0080, Vol. 2011, p. 658956-Article in journal (Refereed)
    Abstract [en]

    Deep brain stimulation of the subthalamic nucleus (STN-DBS) in patients with Parkinson’s disease (PD) affects speech in small, inconsistent ways. However, voice intensity generally increases. Recently the caudal zona inserta (cZi) has been investigated as an alternate target in DBS treatment of PD. The effects of cZi-DBS on voice intensity have not yet been investigated. The aim of this study was to compare the voice intensity effects of cZi-DBS and STN-DBS in PD patients. Voice intensity during reading and intensity decay during rapid syllable repetition were measured for eight STN-DBS and eight cZi-DBS patients in a pre-surgical baseline and then on- and off-stimulation 12 months after surgery. Voice intensity on-stimulation was larger than off-stimulation for the STN-DBS patients, but smaller for the cZi-DBS patients. There were no significant changes in intensity decay. The results suggest that cZi and STN are involved differently in neuromuscular control of the speech respiratory subsystem.

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  • 44. Marklund, Petter
    et al.
    Larsson, Anne
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics.
    Elgh, Eva
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Geriatric Medicine.
    Linder, Jan
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Neurology.
    Riklund Åhlström, Katrine
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology.
    Forsgren, Lars
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Neurology.
    Nyberg, Lars
    Umeå University, Faculty of Medicine, Department of Integrative Medical Biology (IMB), Physiology. Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology.
    Temporal dynamics of basal ganglia under-recruitment in Parkinson's disease: transient caudate abnormalities during updating of working memory.2009In: Brain, ISSN 0006-8950, E-ISSN 1460-2156, Vol. 132, no Pt 2, p. 336-346Article in journal (Refereed)
    Abstract [en]

    Using hybrid-blocked/event-related fMRI and the 2-back task we aimed to decompose tonic and phasic temporal dynamics of basal ganglia response abnormalities in working memory associated with early untreated Parkinson's disease. In view of the tonic/phasic dopamine hypothesis, which posits a functional division between phasic D(2)-dependent striatal updating processes and tonic D(1)-dependent prefrontal context-maintenance processes, we predicted that newly diagnosed, drug-naïve Parkinson's disease patients, with selective striatal dopamine deprivation, would demonstrate transient rather than sustained activation changes in the basal ganglia during 2-back performance. Task-related activation patterns within discrete basal ganglia structures were directly compared between patients and healthy elderly controls. The obtained results yielded uniquely transient underactivation foci in caudate nuclei, putamen and globus pallidus in Parkinson's disease patients, which indicates suboptimal phasic implementation of striatal D(2)-dependent gating mechanisms during updating. Sustained underactivation was only seen in the anterior putamen, which may reflect initial signs of tonic control impairment. No significant changes were exhibited in prefrontal cortex. The present findings resonate well with the tonic/phasic dopamine account and suggest that basal ganglia under-recruitment associated with executive dysfunction in early Parkinson's disease might predominantly stem from deficiencies in phasic executive components subserved by striatum.

  • 45. Memedi, Mevludin
    et al.
    Nyholm, Dag
    Johansson, Anders
    Palhagen, Sven
    Willows, Thomas
    Widner, Hakan
    Linder, Jan
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Westin, Jerker
    Validity and Responsiveness of At-Home Touch Screen Assessments in Advanced Parkinson's Disease2015In: IEEE journal of biomedical and health informatics, ISSN 2168-2194, E-ISSN 2168-2208, Vol. 19, no 6, p. 1829-1834Article in journal (Refereed)
    Abstract [en]

    The aim of this study was to investigate if a telemetry test battery can be used to measure effects of Parkinson's disease (PD) treatment intervention and disease progression in patients with fluctuations. Sixty-five patients diagnosed with advanced PD were recruited in an open longitudinal 36-month study; 35 treated with levodopa-carbidopa intestinal gel (LCIG) and 30 were candidates for switching from oral PD treatment to LCIG. They utilized a test battery, consisting of self-assessments of symptoms and fine motor tests (tapping and spiral drawings), four times per day in their homes during week-long test periods. The repeated measurements were summarized into an overall test score (OTS) to represent the global condition of the patient during a test period. Clinical assessments included ratings on unified PD rating scale (UPDRS) and 39-item PD questionnaire (PDQ-39) scales. In LCIG-naive patients, the mean OTS compared to baseline was significantly improved from the first test period on LCIG treatment until month 24. In LCIG-non naive patients, there were no significant changes in the mean OTS until month 36. The OTS correlated adequately with total UPDRS (rho = 0.59) and total PDQ-39 (0.59). Responsiveness measured as effect size was 0.696 and 0.536 for OTS and UPDRS, respectively. The trends of the test scores were similar to the trends of clinical rating scores but the dropout rate was high. Correlations betweenOTS and clinical rating scales were adequate indicating that the test battery contains important elements of the information of well-established scales. The responsiveness and reproducibility were better for OTS than for total UPDRS.

  • 46.
    Olofsson, Katarina
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Otorhinolaryngology.
    Van Doorn, Jan
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Speech and Language Therapy.
    Kulneff, Linda
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Speech and Language Therapy.
    Linder, Jan
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Neurology.
    Nordh, Erik
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neurophysiology.
    Blomstedt, Patric
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Neurosurgery.
    Djup hjärnstimulering vid dysfagi hos parkinsonpatienter: den självskattade sväljningsfunktionen förbättrades i pilotstudie2010In: Läkartidningen, ISSN 0023-7205, E-ISSN 1652-7518, Vol. 107, no 17, p. 1150-1154Article in journal (Other academic)
  • 47. Palhagen, S. E.
    et al.
    Dizdar, N.
    Hauge, T.
    Holmberg, B.
    Jansson, R.
    Linder, J.
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Nyholm, D.
    Sydow, O.
    Wainwright, M.
    Widner, H.
    Johansson, A.
    Interim analysis of long-term intraduodenal levodopa infusion in advanced Parkinson disease2012In: Acta Neurologica Scandinavica, ISSN 0001-6314, E-ISSN 1600-0404, Vol. 126, no 6, p. e29-e33Article in journal (Refereed)
    Abstract [en]

    Background - This interim 12-month analysis is a part of an open-label, observational, prospective study on health outcomes and cost impact of levodopa/carbidopa intestinal gel (LCIG, Duodopa) in Parkinson disease (PD). The specific aim was to investigate clinical and health-related quality of life (HRQoL) effects in routine care. Methods - Unified PD rating scale (UPDRS) was the primary efficacy measurement. PD QoL questionnaire 39 (PDQ-39) assessed HRQoL. Subjects were assessed at baseline, >= 3 months after surgery, and then every 3 months. Results - Twenty-seven treatment-naive subjects when started with LCIG showed a decrease in UPDRS score that was statistically significant throughout the year: UPDRS total score (mean +/- SD), baseline = 52.1 +/- 16.1, N = 27, month 0 (first visit; at least 3 months after permanent LCIG) = 43.1 +/- 16.7, N = 27, P = 0.003; month 12 = 42.5 +/- 22.6, n = 25, P = 0.017. PDQ-39 results also showed a tendency for improvement: PDQ-39 (mean +/- SD), baseline = 33.6 +/- 10.8, N = 27, month 0 = 27.1 +/- 11.8, N = 27, P = 0.001; 12 months = 28.8 +/- 12.8, n = 23, P = 0.126. Conclusions - LCIG provides functional improvement beginning at first visit that is sustained for 12 months.

  • 48. Pihlstrom, L.
    et al.
    Bjornara, K. -A
    Dizdar, N.
    Fardell, C.
    Forsgren, Lars
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Holmberg, B.
    Larsen, J. P.
    Linder, Jan
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Nissbrandt, H.
    Tysnes, O. -B
    Dietrichs, E.
    Toft, M.
    A Scandinavian multi-centre study replicates 11 susceptibility loci from genome-wide association studies in Parkinson's disease2012In: European Journal of Neurology, ISSN 1351-5101, E-ISSN 1468-1331, Vol. 19, p. 40-40Article in journal (Other academic)
  • 49. Pihlstrom, Lasse
    et al.
    Axelsson, Gunnar
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine. Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Bjornara, Kari Anne
    Dizdar, Nil
    Fardell, Camilla
    Forsgren, Lars
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Holmberg, Björn
    Larsen, Jan Petter
    Linder, Jan
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Nissbrandt, Hans
    Tysnes, Ole-Bjorn
    Öhman, Eilert
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine. Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Dietrichs, Espen
    Toft, Mathias
    Supportive evidence for 11 loci from genome-wide association studies in Parkinson's disease2013In: Neurobiology of Aging, ISSN 0197-4580, E-ISSN 1558-1497, Vol. 34, no 6, p. 1708.e7-1708.e13Article in journal (Refereed)
    Abstract [en]

    Genome-wide association studies have identified a number of susceptibility loci in sporadic Parkinson's disease (PD). Recent larger studies and meta-analyses have greatly expanded the list of proposed association signals. We performed a case-control replication study in a Scandinavian population, analyzing samples from 1345 unrelated PD patients and 1225 control subjects collected by collaborating centers in Norway and Sweden. Single-nucleotide polymorphisms representing 18 loci previously reported at genome-wide significance levels were genotyped, as well as 4 near-significant, suggestive, loci. We replicated 11 association signals at p < 0.05 (SNCA, STK39, MAPT, GPNMB, CCDC62/HIP1R, SYT11, GAK, STX1B, MCCC1/LAMP3, ACMSD, and FGF20). The more recently nominated susceptibility loci were well represented among our positive findings, including 3 which have not previously been validated in independent studies. Conversely, some of the more well-established loci failed to replicate. While future meta-analyses should corroborate disease associations further on the level of common markers, efforts to pinpoint functional variants and understand the biological implications of each risk locus in PD are also warranted. (C) 2013 Elsevier Inc. All rights reserved.

  • 50. Pihlstrøm, Lasse
    et al.
    Rengmark, Aina
    Bjørnarå, Kari Anne
    Dizdar, Nil
    Fardell, Camilla
    Forsgren, Lars
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Holmberg, Björn
    Larsen, Jan Petter
    Linder, Jan
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Nissbrandt, Hans
    Tysnes, Ole-Bjørn
    Dietrichs, Espen
    Toft, Mathias
    Fine mapping and resequencing of the PARK16 locus in Parkinson's disease2015In: Journal of Human Genetics, ISSN 1434-5161, E-ISSN 1435-232X, Vol. 60, no 7, p. 357-362Article in journal (Refereed)
    Abstract [en]

    The PARK16 locus, spanning five genes on chromosome 1, was among the first genetic regions to show genome-wide association in Parkinson's disease (PD). Subsequent investigations have found variability in PARK16 top-hits and association patterns across populations, and the implicated genes and mechanisms are currently unclear. In the present study, we aimed to explore the contribution of PARK16 variability to PD risk in a Scandinavian population. We genotyped 17 single-nucleotide polymorphisms in a case-control sample set of 2570 individuals from Norway and Sweden to fine map the locus. Targeted resequencing of the full coding regions of SLC45A3, NUCKS1, RAB7L1, SLC41A1 and PM20D1 was performed in DNA pools from a subset of 387 patient samples. We find evidence for an association with PD for rs1775143 as well as a haplotype located around the 5' region of RAB7L1, implicating variants which are not in high linkage disequilibrium with the strongest signal from a recent large meta-analysis in Caucasians. We also provide suggestive support for epistasis between RAB7L1 and LRRK2 as previously hypothesized by others. Comparing our results with previous work, allelic heterogeneity at PARK16 appears likely, and further studies are warranted to disentangle the complex patterns of association and pinpoint the functionally relevant variants.

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