umu.sePublications
Change search
Link to record
Permanent link

Direct link
BETA
Alternative names
Publications (10 of 76) Show all publications
Kleyko, D., Osipov, E. & Wiklund, U. (2019). A Hyperdimensional Computing Framework for Analysis of Cardiorespiratory Synchronization During Paced Deep Breathing. IEEE Access, 7, 34403-34415
Open this publication in new window or tab >>A Hyperdimensional Computing Framework for Analysis of Cardiorespiratory Synchronization During Paced Deep Breathing
2019 (English)In: IEEE Access, E-ISSN 2169-3536, Vol. 7, p. 34403-34415Article in journal (Refereed) Published
Abstract [en]

Autonomic function during deep breathing (DB) is normally scored based on the assumption that the heart rate is synchronized with the breathing. We have observed individuals with subtle arrhythmias during DB, where an autonomic function cannot be evaluated. This paper presents a novel method for analyzing cardiorespiratory synchronization: feature-based analysis of the similarity between heart rate and respiration using the principles of hyperdimensional computing. Heart rate and respiration signals were modeled using Fourier series analysis. Three feature variables were derived and mapped to binary vectors in a high-dimensional space. Using both synthesized data and recordings from patients/healthy subjects, the similarity between the feature vectors was assessed using Hamming distance (high-dimensional space), Euclidean distance (original space), and with a coherence-based index. Methods were evaluated via the classification of the similarity indices into three groups. The distance-based methods achieved good separation of signals into classes with different degrees of cardiorespiratory synchronization, also providing identification of patients with low cardiorespiratory synchronization but high values of conventional DB scores. Moreover, binary high-dimensional vectors allowed an additional analysis of the obtained Hamming distance. Feature-based similarity analysis using hyperdimensional computing is capable of identifying signals with low cardiorespiratory synchronization during DB due to arrhythmias. Vector-based similarity analysis could be applied to other types of feature variables than based on spectral analysis. The proposed methods for robustly assessing cardiorespiratory synchronization during DB facilitate the identification of individuals where the evaluation of the autonomic function is problematic or even impossible, thus increasing the correctness of the conventional DB scores.

Place, publisher, year, edition, pages
Institute of Electrical and Electronics Engineers (IEEE), 2019
Keywords
Deep breathing test, deep breathing index, similarity analysis, heart rate variability, hyperdimensional computing
National Category
Computer Systems
Identifiers
urn:nbn:se:umu:diva-158768 (URN)10.1109/ACCESS.2019.2904311 (DOI)000463487400001 ()
Available from: 2019-05-08 Created: 2019-05-08 Last updated: 2019-05-08Bibliographically approved
Katsogiannos, P., Kamble, P. G., Hammar, U., Sundbom, M., Wiklund, U., Pereira, M. J. & Eriksson, J. W. (2019). Early effects of RYGB on hormone regulation and autonomic nerve activity in patients with obesity and type 2 diabetes. Paper presented at 55th Annual Meeting of the European-Association-for-the-Study-of-Diabetes (EASD), SEP 16-20, 2019, Barcelona, SPAIN. Diabetologia, 62, S274-S274
Open this publication in new window or tab >>Early effects of RYGB on hormone regulation and autonomic nerve activity in patients with obesity and type 2 diabetes
Show others...
2019 (English)In: Diabetologia, ISSN 0012-186X, E-ISSN 1432-0428, Vol. 62, p. S274-S274Article in journal, Meeting abstract (Other academic) Published
Place, publisher, year, edition, pages
Springer, 2019
National Category
Endocrinology and Diabetes
Identifiers
urn:nbn:se:umu:diva-164067 (URN)000485303802162 ()
Conference
55th Annual Meeting of the European-Association-for-the-Study-of-Diabetes (EASD), SEP 16-20, 2019, Barcelona, SPAIN
Note

Supplement: 1 

Special Issue: SI 

Meeting Abstract: 567

Available from: 2019-10-16 Created: 2019-10-16 Last updated: 2019-10-16Bibliographically approved
Katsogiannos, P., Kamble, P. G., Hammar, U., Sundbom, M., Wiklund, U., Pereira, M. J. & Eriksson, J. W. (2019). Early effects of RYGB on hormone regulation and autonomic nerve activity in patients with obesity and type 2 diabetes. Paper presented at 55th Annual Meeting of the European-Association for the Study of Diabetes (EASD), Barcelona, SEP 16-20, 2019. Diabetologia, 62, S274-S274
Open this publication in new window or tab >>Early effects of RYGB on hormone regulation and autonomic nerve activity in patients with obesity and type 2 diabetes
Show others...
2019 (English)In: Diabetologia, ISSN 0012-186X, E-ISSN 1432-0428, Vol. 62, p. S274-S274Article in journal, Meeting abstract (Refereed) Published
Place, publisher, year, edition, pages
Springer, 2019
National Category
Endocrinology and Diabetes
Identifiers
urn:nbn:se:umu:diva-164147 (URN)000485303802162 ()
Conference
55th Annual Meeting of the European-Association for the Study of Diabetes (EASD), Barcelona, SEP 16-20, 2019
Note

Supplement 1, Special Issue. Meeting abstract 567.

Available from: 2019-10-17 Created: 2019-10-17 Last updated: 2019-10-17Bibliographically approved
Almby, K. E., Abrahamsson, N., Lundqvist, M. H., Hammara, U., Thombare, K., Panagiotou, A., . . . Eriksson, J. W. (2019). Effects of GLP-1 on counter-regulatory responses during hypoglycemia after GBP surgery. European Journal of Endocrinology, 181(2), 161-171
Open this publication in new window or tab >>Effects of GLP-1 on counter-regulatory responses during hypoglycemia after GBP surgery
Show others...
2019 (English)In: European Journal of Endocrinology, ISSN 0804-4643, E-ISSN 1479-683X, Vol. 181, no 2, p. 161-171Article in journal (Refereed) Published
Abstract [en]

Objectives: The aim of the study was to explore the role of GLP-1 receptor activation on the counter-regulation and symptoms of hypoglycemia in subjects who have undergone gastric bypass surgery (GBP).

Design: Experimental hyperinsulinemic–hypoglycemic clamp study.

Methods: Twelve post-GBP subjects participated in a randomized cross-over study with two hyperinsulinemic, hypoglycemic clamps (glucose nadir 2.7 mmol/L) performed on separate days with concomitant infusions of the GLP-1 analog exenatide or with saline, respectively. Continuous measurements of metabolites and counter-regulatory hormones as well as assessments of heart rate variability and symptoms of hypoglycemia were performed throughout the clamps.

Results: No effect of GLP-1 receptor activation on counter-regulatory hormones (glucagon, catecholamines, cortisol, GH) or glucose infusion rate was seen, but we found indications of a downregulation of the sympathetic relative to the parasympathetic nerve activity, as reflected in heart rate variability. No significant differences in symptom of hypoglycemia were observed.

Conclusions/interpretation: Short-term exposure to a GLP-1 receptor agonist does not seem to impact the counter-regulatory hormonal and metabolic responses in post-GBP subjects during hypoglycemic conditions, suggesting that the improvement in symptomatic hypoglycemia post-GBP seen following treatment with GLP-1 receptor agonists may be mediated by mechanism not directly involved in counter-regulation.

Place, publisher, year, edition, pages
Bioscientifica, 2019
National Category
Endocrinology and Diabetes
Identifiers
urn:nbn:se:umu:diva-161569 (URN)10.1530/EJE-19-0171 (DOI)000472835100013 ()31176298 (PubMedID)
Funder
Swedish Diabetes Association
Available from: 2019-07-25 Created: 2019-07-25 Last updated: 2019-07-25Bibliographically approved
Almby, K. E., Abrahamsson, N., Lundqvist, M. H., Hammar, U., Thombare, K., Panagiotou, A., . . . Eriksson, J. W. (2019). Effects of GLP-1 receptor activation on counterregulatory responses during hypoglycaemia after gastric bypass surgery: no evidence for GLP-1 as a counterregulatory hormone. Paper presented at 55th Annual Meeting of the European-Association-for-the-Study-of-Diabetes (EASD), SEP 16-20, 2019, Barcelona, SPAIN. Diabetologia, 62, S416-S416
Open this publication in new window or tab >>Effects of GLP-1 receptor activation on counterregulatory responses during hypoglycaemia after gastric bypass surgery: no evidence for GLP-1 as a counterregulatory hormone
Show others...
2019 (English)In: Diabetologia, ISSN 0012-186X, E-ISSN 1432-0428, Vol. 62, p. S416-S416Article in journal, Meeting abstract (Other academic) Published
Place, publisher, year, edition, pages
Springer, 2019
National Category
Endocrinology and Diabetes
Identifiers
urn:nbn:se:umu:diva-164066 (URN)000485303803183 ()
Conference
55th Annual Meeting of the European-Association-for-the-Study-of-Diabetes (EASD), SEP 16-20, 2019, Barcelona, SPAIN
Note

Supplement: 1 

Special Issue: SI 

Meeting Abstract: 855

Available from: 2019-10-16 Created: 2019-10-16 Last updated: 2019-10-16Bibliographically approved
Almby, K. E., Abrahamsson, N., Lundqvist, M. H., Hammar, U., Thombare, K., Panagiotou, A., . . . Eriksson, J. W. (2019). Effects of GLP-1 receptor activation on counterregulatory responses during hypoglycaemia after gastric bypass surgery: no evidence for GLP-1 as a counterregulatory hormone. Paper presented at 55th Annual Meeting of the European Association for the Study of Diabetes (EASD), Bercelona, SEP 16-20, 2019. Diabetologia, 62, S416-S416
Open this publication in new window or tab >>Effects of GLP-1 receptor activation on counterregulatory responses during hypoglycaemia after gastric bypass surgery: no evidence for GLP-1 as a counterregulatory hormone
Show others...
2019 (English)In: Diabetologia, ISSN 0012-186X, E-ISSN 1432-0428, Vol. 62, p. S416-S416Article in journal, Meeting abstract (Refereed) Published
Place, publisher, year, edition, pages
Springer, 2019
National Category
Endocrinology and Diabetes
Identifiers
urn:nbn:se:umu:diva-164146 (URN)000485303803183 ()
Conference
55th Annual Meeting of the European Association for the Study of Diabetes (EASD), Bercelona, SEP 16-20, 2019
Note

Supplement 1, Special Issue. Meeting abstract 855.

Available from: 2019-10-17 Created: 2019-10-17 Last updated: 2019-10-17Bibliographically approved
Alenius Dahlqvist, J., Sunnegårdh, J., Hanséus, K., Strömvall Larsson, E., Nygren, A., Dalén, M., . . . Rydberg, A. (2019). Pacemaker treatment after Fontan surgery: a Swedish national study. Congenital Heart Disease
Open this publication in new window or tab >>Pacemaker treatment after Fontan surgery: a Swedish national study
Show others...
2019 (English)In: Congenital Heart Disease, ISSN 1747-079X, E-ISSN 1747-0803Article in journal (Other academic) Epub ahead of print
Abstract [en]

Objective: Fontan surgery is performed in children with univentricular heart defects. Previous data regarding permanent pacemaker implantation frequency and indications in Fontan patients are limited and conflicting. We examined the prevalence of and risk factors for pacemaker treatment in a consecutive national cohort of patients after Fontan surgery in Sweden.

Methods: We retrospectively reviewed all Swedish patients who underwent Fontan surgery from 1982 to 2017 (n = 599).

Results: After a mean follow‐up of 12.2 years, 13% (78/599) of the patients with Fontan circulation had received pacemakers. Patients operated with the extracardiac conduit (EC) type of total cavopulmonary connection had a significantly lower prevalence of pacemaker implantation (6%) than patients with lateral tunnel (LT; 17%). Mortality did not differ between patients with (8%) and without pacemaker (5%). The most common pacemaker indication was sinus node dysfunction (SND) (64%). Pacemaker implantation due to SND was less common among patients with EC. Pacemaker implantation was significantly more common in patients with mitral atresia (MA; 44%), double outlet right ventricle (DORV; 24%) and double inlet left ventricle (DILV; 20%). In contrast, patients with pulmonary atresia with intact ventricular septum and hypoplastic left heart syndrome were significantly less likely to receive a pacemaker (3% and 6%, respectively).

Conclusions: Thirteen percent of Fontan patients received a permanent pacemaker, most frequently due to SND. EC was associated with a significantly lower prevalence of pacemaker than LT. Permanent pacemaker was more common in patients with MA, DORV, and DILV.

Place, publisher, year, edition, pages
Wiley-Blackwell, 2019
Keywords
Congenital heart disease, Fontan circulation, pacemaker treatment, sinus node dysfunction
National Category
Pediatrics
Research subject
Pediatrics; Cardiology
Identifiers
urn:nbn:se:umu:diva-156716 (URN)10.1111/chd.12766 (DOI)
Funder
Västerbotten County CouncilSwedish Heart Lung Foundation
Note

Originally included in thesis in manuscript form.

Available from: 2019-02-25 Created: 2019-02-25 Last updated: 2019-03-19
Alenius Dahlqvist, J., Wiklund, U., Karlsson, M., Hanseus, K., Stromvall-Larsson, E., Nygren, A., . . . Rydberg, A. (2019). Sinus node dysfunction in patients with Fontan circulation: could heart rate variability be a predictor for pacemaker implantation?. Pediatric Cardiology, 40(4), 685-693
Open this publication in new window or tab >>Sinus node dysfunction in patients with Fontan circulation: could heart rate variability be a predictor for pacemaker implantation?
Show others...
2019 (English)In: Pediatric Cardiology, ISSN 0172-0643, E-ISSN 1432-1971, Vol. 40, no 4, p. 685-693Article in journal (Refereed) Published
Abstract [en]

Sinus node dysfunction (SND) causes significant morbidity in patients after Fontan surgery. Heart rate variability (HRV) reflects the autonomic regulation of the heart, and changes in HRV have been associated with SND in adults. We aimed to study whether changes in HRV could be detected in 24-h electrocardiographic (ECG) recordings in Fontan patients with SND. We compared HRV results from two patient groups; patients with Fontan circulation who later required a pacemaker due to severe SND (n = 12) and patients with Fontan circulation and SND, without indication for pacemaker treatment (n = 11), with two control groups; patients with Fontan circulation without SND (n = 90) and healthy controls (n = 66). The Poincare plot index SD2 (representing changes in heart rate over 24-h) and the very low-frequency (VLF) HRV component were significantly higher in both SND groups, both compared with healthy controls and patients with Fontan circulation without SND. In SND patients with pacemakers, SD2 and VLF were slightly reduced compared to SND patients without pacemaker (p = 0.06). In conclusion, in Fontan patients with SND the HRV is significantly higher compared to healthy controls and Fontan patients without SND. However, in patients with severe SND requiring pacemaker, SD2 and VLF tended to be lower than in patients with SND without pacemaker, which could indicate a reduced diurnal HRV in addition to the severe bradycardia. This is a small study, but our results indicate that HRV analysis might be a useful method in the follow-up of Fontan patients regarding development of SND.

Place, publisher, year, edition, pages
Springer-Verlag New York, 2019
Keywords
Congenital heart disease, Fontan circulation, Pacemaker, Sinus node dysfunction, Heart rate variability, Poincare analysis
National Category
Cardiac and Cardiovascular Systems Pediatrics
Identifiers
urn:nbn:se:umu:diva-158740 (URN)10.1007/s00246-019-02092-5 (DOI)000463707500002 ()30918992 (PubMedID)
Available from: 2019-05-20 Created: 2019-05-20 Last updated: 2019-05-20Bibliographically approved
Boles, U., Johansson, A., Wiklund, U., Sharif, Z., David, S., McGrory, S. & Henein, M. Y. (2018). Cytokine Disturbances in Coronary Artery Ectasia Do Not Support Atherosclerosis Pathogenesis. International Journal of Molecular Sciences, 19(1), Article ID 260.
Open this publication in new window or tab >>Cytokine Disturbances in Coronary Artery Ectasia Do Not Support Atherosclerosis Pathogenesis
Show others...
2018 (English)In: International Journal of Molecular Sciences, ISSN 1422-0067, E-ISSN 1422-0067, Vol. 19, no 1, article id 260Article in journal (Refereed) Published
Abstract [en]

BACKGROUND: Coronary artery ectasia (CAE) is a rare disorder commonly associated with additional features of atherosclerosis. In the present study, we aimed to examine the systemic immune-inflammatory response that might associate CAE.

METHODS: Plasma samples were obtained from 16 patients with coronary artery ectasia (mean age 64.9 ± 7.3 years, 6 female), 69 patients with coronary artery disease (CAD) and angiographic evidence for atherosclerosis (age 64.5 ± 8.7 years, 41 female), and 140 controls (mean age 58.6 ± 4.1 years, 40 female) with normal coronary arteries. Samples were analyzed at Umeå University Biochemistry Laboratory, Sweden, using the V-PLEX Pro-Inflammatory Panel 1 (human) Kit. Statistically significant differences (p < 0.05) between patient groups and controls were determined using Mann-Whitney U-tests.

RESULTS: The CAE patients had significantly higher plasma levels of INF-γ, TNF-α, IL-1β, and IL-8 (p = 0.007, 0.01, 0.001, and 0.002, respectively), and lower levels of IL-2 and IL-4 (p < 0.001 for both) compared to CAD patients and controls. The plasma levels of IL-10, IL-12p, and IL-13 were not different between the three groups. None of these markers could differentiate between patients with pure (n = 6) and mixed with minimal atherosclerosis (n = 10) CAE.

CONCLUSIONS: These results indicate an enhanced systemic pro-inflammatory response in CAE. The profile of this response indicates activation of macrophages through a pathway and trigger different from those of atherosclerosis immune inflammatory response.

Place, publisher, year, edition, pages
Basel, Switzerland: MDPI, 2018
Keywords
atherosclerosis, coronary artery disease, coronary artery ectasia, cytokines, immune inflammatory response, macrophage activation
National Category
Cardiac and Cardiovascular Systems
Research subject
Epidemiology
Identifiers
urn:nbn:se:umu:diva-144041 (URN)10.3390/ijms19010260 (DOI)000424407200254 ()29337902 (PubMedID)
Funder
Swedish Heart Lung Foundation
Available from: 2018-01-26 Created: 2018-01-26 Last updated: 2019-09-23Bibliographically approved
Wadell, K., Wiklund, U., Öhberg, F., Bergmann, E., Holmner, Å. & Blomberg, A. (2018). Longitudinal, home-based study of lung function, saturation and disease-related symptoms in COPD. Paper presented at 28th International Congress of the European-Respiratory-Society (ERS), SEP 15-19, 2018, Paris, FRANCE. European Respiratory Journal, 52
Open this publication in new window or tab >>Longitudinal, home-based study of lung function, saturation and disease-related symptoms in COPD
Show others...
2018 (English)In: European Respiratory Journal, ISSN 0903-1936, E-ISSN 1399-3003, Vol. 52Article in journal, Meeting abstract (Other academic) Published
Abstract [en]

Background: Many telehealth (TH) systems have been designed to identify signs of COPD exacerbations, but few previous studies have reported the nature of recorded lung function data and what variations to expect in stable versus unstable patients.

Aims: To evaluate the nature of individual diurnal, day-to-day and long-term variation in important prognostic markers of COPD exacerbations in a heterogeneous patient group by employing a newly developed TH system.

Methods: Eight women and five men with COPD performed measurements (FEV1, IC, SpO2 and CAT) three times per week during 4-6 months using the TH system. Feasibility was based on the repeatability and quality of the FEV1 and IC measurements, as defined by ERS/ATS guidelines. Short-term and long-term individual variations were assessed using the relative density and mean (SD) respectively.

Results: Close to 1100 FEV1 and IC measurements respectively were performed during a total of 240 patient weeks. The 2SD ranges for intra-individual variation were ± 210 mL and ± 350 mL for FEV1 and IC respectively. The values both increased and decreased without corresponding influence on symptoms (CAT) or SpO2 and no exacerbation was reported. However, it was unusual with a decrease of more than 50 mL per measurement in FEV1 between three consecutive measurement days.

Conclusions: This study reveals important and, to our knowledge, previously not reported information about short and long-term variability in lung function measurements in stable patients with COPD, of significance when defining criteria for detecting exacerbations with TH systems.

Place, publisher, year, edition, pages
European Respiratory Society, 2018
National Category
Respiratory Medicine and Allergy
Identifiers
urn:nbn:se:umu:diva-155993 (URN)10.1183/13993003.congress-2018.PA3828 (DOI)000455567104471 ()
Conference
28th International Congress of the European-Respiratory-Society (ERS), SEP 15-19, 2018, Paris, FRANCE
Available from: 2019-02-07 Created: 2019-02-07 Last updated: 2019-02-07Bibliographically approved
Projects
State-space approach for analysis of the short-term interactions in systems with circular causality: Assessment of the autonomic control of heart rate and blood pressure variability [2008-03292_VR]; Umeå UniversityRealtime interactive cognitive architecture for prediction of autonomic cardiovascular dysregulation [2015-04677_VR]; Umeå University
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0002-1313-0934

Search in DiVA

Show all publications