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Objectives: This study aimed to assess the relationship between dietary intake and disease outcomes in patients with radiographic axial spondyloarthritis (r-axSpA), focusing on inflammation and disease activity, while also evaluating other health outcomes, and to compare dietary intake between patients and controls.

Method: In a cross-sectional analysis, we studied 295 patients with r-axSpA (modified New York criteria for ankylosing spondylitis) in northern and south-western Sweden. Of these, 155 were of similar age to controls (50–64 years) from the Swedish CArdioPulmonary bioImage Study (SCAPIS) and were matched on sex, age, and geographical location to 604 controls. Dietary intake was evaluated using the MiniMealQ food frequency questionnaire. Differences in dietary intake between patients and controls were assessed in conditional logistic regression models. Nutrients with significant group differences were examined in patients (n = 295) by regression models for the outcomes Ankylosing Spondylitis Disease Activity Score with C-reactive protein (CRP) (ASDAS) and CRP.

Results: Patients had a lower dietary fibre density, as well as lower intake of marine omega-3 fatty acids, calcium, folate, iodine, phosphorus, potassium, selenium, vitamins A, C, and K, β-carotene, and alcohol. Low intake of marine omega-3 fatty acids was associated with a higher ASDAS, and a lower dietary fibre density was associated with elevated CRP.

Conclusions: Patients with r-axSpA report lower dietary quality compared with controls. Dietary intake is related to disease activity and inflammation. Further exploration of metabolic biomarkers and disease outcomes is warranted, and the impact of a health-promoting dietary intervention should be assessed.

Purpose: To compare clinical outcomes of customized transepithelial (epi-on) corneal crosslinking (CXL) in high oxygen and customized CXL with epithelial removal (epi-off) in room air for keratoconus (KC).

Setting: Umeå University Hospital, Umeå, Sweden.

Design: Prospective, randomized, single-masked, intraindividually comparing study.

Methods: 32 participants with bilateral progressive KC were treated with bilateral customized topography-guided CXL, 30 mW/cm2; 7.2 to 15 J/cm2and were randomized to epi-on in one eye (32 eyes) and epi-off in the fellow eye (32 eyes). Uncorrected distance visual acuity (UDVA) and corrected distance visual acuity (CDVA), maximal keratometry (Kmax), subjective ocular discomfort, low-contrast visual acuities (LCVAs) at 10% and 2.5% contrast, ocular and anterior corneal wavefront aberrations, manifest refractive spherical equivalent, endothelial cell count (ECC), and adverse events were assessed through 24 months.

Results: Both treatments showed improvements at 24 months in UDVA; -0.16 ± 0.24 (P <.001) and -0.13 ± 0.20 logMAR (P =.006), respectively, CDVA; -0.10 ± 0.11 (P <.001) and -0.10 ± 0.12 (P =.001), Kmax; -1.74 ± 1.31 (P <.001) and -1.72 ± 1.36 D (P <.001). LCVA 10% improved for both protocols (P <.001), but LCVA 2.5% improved for epi-on CXL only (P =.001). ECC was unaltered, and no adverse events occurred. The epi-on eyes had significantly less discomfort symptoms during the whole first week posttreatment (P <.05).

Conclusions: High-oxygen customized epi-on CXL is a viable alternative to room air customized epi-off CXL, with faster improvements in CDVA and LCVA and less early ocular discomfort.

BACKGROUND: Radiographic axial spondyloarthritis (r-axSpA) is one of the most common chronic inflammatory rheumatic diseases, affecting about 0.2% of the Swedish population. Adequate nutritional intake is essential for maintaining physiological functions. A poor diet increases the risk of developing conditions such as obesity, osteoporosis, and/or atherosclerosis. Diet quality is also theorized to affect systemic inflammation. Dietary habits in patients with r-axSpA are largely unknown. The aims of this study were to assess dietary nutrient intake in r-axSpA patients and examine whether it differs compared to persons without r-axSpA.

METHODS: r-axSpA patients (modified NY criteria) at the rheumatology clinic in Region Västerbotten, northern Sweden, were invited to take part in the Backbone study which investigates disease severity and comorbidities. In total, 155 patients were included. Nutritional intake was assessed by the semi-quantitative food frequency questionnaire MiniMeal-Q. Controls were collected from the Swedish CArdioPulmonary bioImage Study (n = 30,154), a study that invited participants 50-64 years of age by random selection from the Swedish population register. Out of the 155 r-axSpA patients, 81 were in the same age span. Four controls were identified for each patient, matched on age (± 1 year), sex, and geographic location. Data on dietary intake was available for 319 controls. Statistical comparisons of dietary intake between patients with r-axSpA and controls were done by exact conditional logistic regression analysis, adjusted for country of birth, educational level, single household, weight, smoking status, and energy intake.

RESULTS: Patients had a comparatively significantly higher energy intake from carbohydrates, a lower fiber density, and a lower intake of marine omega-3 fatty acids. Furthermore, intake of vitamins D, E, and K as well as selenium, folate, calcium, magnesium, phosphorus, potassium, vitamin A, and β-carotene (a precursor of vitamin A and marker of vegetable and fruit intake) was significantly lower among patients compared to controls.

CONCLUSIONS: Our results suggest that r-axSpA patients have an impaired dietary intake. Notably, intake was lower in several nutrients theorized to have anti-inflammatory properties (fiber density, marine-omega-3 fatty acids, vitamin D, and selenium). We further propose that nutrition screening might be incorporated into the management of r-axSpA patients.

Background: Physical function is an important determinant of health-related quality of life in radiographic axial spondyloarthritis patients (r-axSpA). To improve the basis of effective healthcare efforts, we aimed to investigate which demographic and disease-related factors that influence Bath Ankylosing Spondylitis Functional Index (BASFI) in r-axSpA patients overall and stratified by sex. Furthermore, we sought to explore differences between sexes regarding separate BASFI questions and also to explore which factors that may contribute to these differences.

Methods: This observational cross-sectional study included patients fulfilling the modified New York criteria for Ankylosing Spondylitis. Patients were assessed with 66/68 joint count and Bath Ankylosing Spondylitis Metrology Index (BASMI) measurements. Lateral X-rays were performed for Modified Stoke Ankylosing Spondylitis Spinal Score (mSASSS). Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Ankylosing Spondylitis Disease Activity Score (ASDAS)-C-Reactive Protein (CRP), and BASFI were registered. Multivariable linear regression analyses were used to investigate which factors that associate with BASFI.

Results: A total of 353 r-axSpA patients were included, mean age 52.2 ± 12.7 years, 62.3% males. No significant sex difference was seen in BASFI scores (2.7 ± 2.0 in males vs 2.9 ± 2.1 in females). Age, body mass index, ASDAS-CRP, BASMI or mSASSS, fatigue, and tenderness were found to associate independently with BASFI in different models (R 2 0.53–0.63). Investigation of separate BASFI questions revealed that the ability to look over shoulder was worse in males than females (mean 4.43 ± 3.37 vs 3.74 ± 3.06, p = 0.05) and most strongly correlated with mSASSS and BASMI among separate BASFI questions (r = 0.53, p < 0.001; r = 0.62, p < 0.001). The ability to climb stairs was worse in females than males (mean 2.49 ± 2.77 vs 1.54 ± 2.32, p < 0.001).

Conclusions: No difference between male and female r-axSpA patients was seen in BASFI despite significant sex differences in BASMI, mSASSS, and CRP levels. Our results underline the impact of fatigue and tenderness on BASFI. The ability to climb stairs without a handrail was scored worse among females compared to males. Furthermore, the ability to look over the shoulder was worse in males than females and closely related to spinal mobility and structural spinal changes.

Purpose: To compare two annular epithelium-on (epi-on) high oxygen photorefractive intrastromal cross-linking (PiXL) illuminations protocols for treatment of low-grade myopia.

Methods: In this randomized, single-masked, intra-individually comparative study, healthy individuals with bilateral low-grade myopia (manifest refractive spherical equivalent (MRSE) −0.75 diopters (D) to −2.50 D) were treated with high oxygen epi-on PiXL. One eye was randomized to receive pulsed accelerated 365-nm ultraviolet-A illumination in a central annular zone of 4.0 mm (1 second on, 1 second off; 30 mW/cm2), and the fellow eye in a 3.5 mm annular zone (0.5 second on, 1 second off; 45 mW/cm2). Uncorrected distance visual acuity (UDVA), MRSE, low-contrast visual acuity (LCVA), best spectacle corrected visual acuity (BSCVA), endothelial cell count (ECC) and Scheimpflug light scattering depths were assessed through 24-month follow-up.

Results: Twenty-seven participants (54 eyes) were included. The 3.5 mm protocol rendered less subjective ocular discomfort posttreatment and a larger improvement than the 4.0 mm protocol in UDVA: −0.52 (−0.72, −0.32) logMAR (medians and interquartile ranges, IQR) and −0.38 (−0.50, −0.22), p = 0.003 and MRSE: +1.25 D (0.75, 1.50) and +1.0 (0.75, 1.0), p = 0.037. The transient reduction in LCVA was larger with the 3.5 mm protocol (p < 0.01). No adverse events, and no reductions in ECC or BSCVA were noted.

Conclusion: Epi-on PiXL in high oxygen reduces myopia in healthy eyes. A larger reduction of myopia and less early posttreatment subjective ocular discomfort can be seen with a smaller treatment zone, but likely at the expense of a transient decrease in low-contrast visual acuity.

Purpose: To assess the effect of two high-oxygen epi-on PiXL treatments for low-grade myopia.

Methods: This prospective, randomized, intra-individually comparing, single-masked study included 23 healthy volunteers (46 eyes) aged 18-35 years with mild myopia, -0.75 to -2.50 D manifest refractive spherical equivalent (MRSE). One eye was randomized to a 4.0-mm homogenous treatment zone and the fellow eye to a 4.0-mm annular zone (16:40 min at 30 mW/cm(2), fluence 15 J/cm(2)). Uncorrected distance visual acuity (UDVA), MRSE, best spectacle-corrected visual acuity (BSCVA), Scheimpflug light scattering depths, mean keratometry (K-mean) and endothelial cell count (ECC) were assessed through 24 months.

Results: Similar improvements in UDVA were seen for the homogeneous and annular protocols at 1 month: -0.52 (-0.59, -0.39) and -0.49 (-0.59, -0.39) logMAR, respectively (medians and interquartile ranges, IQR), p = 0.91, and MRSE: +1.0 D (0.94, 1.31) and +1.0 D (0.69, 1.25), p = 0.17. Light scattering depths were 496 (465, 527) and 349 (247, 378) mu m, respectively, and the reduction in mean keratometry was -0.8 D (-1.1, -0.7) and 0 D (-0.1, 0.1), p < 0.001. The treatment effect remained stable throughout 24 months. At 1 week, the participants reported less ocular discomfort with the annular protocol. No reductions were seen in BSCVA or ECC. No adverse events were reported.

Conclusion: PiXL can reduce low-grade myopia and improve uncorrected vision in healthy eyes. The initial ocular discomfort may be reduced with an annular treatment zone. Further studies are needed to optimize PiXL treatment parameters.

Background: Knowledge about health related quality of life (HRQoL) in Ankylosing spondylitis (AS) is limited. The aims of this study were to assess HRQoL by short form-36 (SF-36) in a cohort of patients with AS compared with controls and to examine associations between SF-36 and spinal radiographic changes, physical function, disease activity and demographic data overall and stratified by sex.

Method: A cohort of patients with AS were assessed with spinal radiographs for mSASSS, BASMI, BASFI, ASDAS-CRP, BASDAI, BASG and SF-36. Each patient’s SF-36 results were compared with 5 age- and sex-matched persons (n=1055) from the SF-36 Swedish normative population database. Associations between SF-36 physical component summary (PCS) and mental component summary (MCS) scores and disease related and demographic factors were investigated with univariate and multiple logistic regression analyses with PCS and MCS below/above their respective median values as dependent variables.

Results: 210 patients, age (median, IQR) 49.0 (40.0, 61.2) years were included. AS patients scored lower (p<0.001) compared to controls in all SF-36 domains and component summaries. Both sexes scored significantly lower in PCS compared to MCS. Multiple logistic regression analyses revealed that living without a partner (OR 2.38, 95% CI 1.00–5.67), long symptom duration (year in decade OR 1.66, 95% CI 1.16–2.37), higher BASFI (OR 1.98, 95% CI 1.46–2.70) and ASDAS≥2.1 (OR 3.32, 95% CI 1.45-7.62) were associated with worse PCS, while living without a partner (OR 3.04, 95% CI 1.34–6.91), fatigue (VAS global fatigue >median (OR 6.36, 95% CI 3.06–13.19) and ASDAS≥2.1 (OR 2.97, 95% CI 1.41–6.25) were associated with worse MCS.

Conclusions: AS patients had significantly lower HRQoL compared with controls. PCS was more affected than MCS in both sexes. Both disease related and demographic factors were associated with HRQoL, partly overlapping for PCS and MCS. Factors associated with HRQoL showed some differences between sexes. Modifying factors, such as ASDAS-CRP and fatigue, may improve HRQoL.

Background: Ankylosing spondylitis (AS) begins early in life and often leads to reduced physical function, but less is known about the impacts it has on health-related quality of life (HRQoL). The aims of this study were to assess HRQoL using the Short Form-36 (SF-36) in a cohort of patients with AS compared with controls and to examine associations between SF-36 scores and spinal radiographic changes, physical function, disease activity and demographic data overall and stratified by sex.

Methods: A cohort of patients with AS from Western Sweden were assessed using the Modified Stoke Ankylosing Spondylitis Spine Score (mSASSS) with spinal radiographs, clinical examination and questionnaires, including the Bath Ankylosing Spondylitis Metrology Index, Bath Ankylosing Spondylitis Functional Index (BASFI), Ankylosing Spondylitis Disease Activity Score-C-reactive protein (ASDAS-CRP), Bath Ankylosing Spondylitis Disease Activity Index, Bath Ankylosing Spondylitis Patient Global (BASG) and SF-36. Each patient's SF-36 results were compared with those of five age-matched and sex-matched persons (n=1055) from the SF-36 Swedish normative population database. Associations between SF-36 physical component summary (PCS) and mental component summary (MCS) scores and disease-related and demographic factors were investigated using univariate and multivariable ogistic regression analyses with PCS and MCS below/above their respective median values as dependent variables.

Results: A total of 210 patients, age (median, IQR) 49.0 (21.2) years, symptom duration 24.0 (21.0) years, men 57.6% and HLAB27 87.1% were included. Patients with AS scored significantly lower (p<0.001) compared to controls in all SF-36 domains and component summaries; PCS 42.4 (14.5) in AS versus 52.4 (11.8) in controls and MCS 47.9 (20.0) in AS versus 54.1 (10.1) in controls. Both men and women scored significantly lower in PCS compared with MCS. Multivariable logistic regression analyses revealed that living without a partner (OR 2.38, 95% CI 1.00-5.67), long symptom duration (year in decade OR 1.66, 95% CI 1.16-2.37), higher BASFI (OR 1.98, 95% CI 1.46-2.70) and ASDAS 2.1 (OR 3.32, 95% CI 1.45-7.62) were associated with worse PCS, while living without a partner (OR 3.04, 95% CI 1.34-6.91), fatigue (visual analogue scale for global fatigue greater than the median (OR 6.36, 95% CI 3.06-13.19) and ASDAS 2.1 (OR 2.97, 95% CI 1.41-6.25) with worse MCS. Some differences between sexes were observed in the results.

Conclusions: The patients with AS had significantly lower HRQoL compared with controls. PCS was more affected compared to MCS in both sexes. Both disease-related and demographic factors were associated with HRQoL, partly overlapping for PCS and MCS. Factors associated with HRQoL showed some differences between sexes. By modifying factors, such as ASDAS-CRP and fatigue, HRQoL may potentially be improved.

Background: Today corneal crosslinking with ultraviolet-A photoactivation of riboflavin is an established method to halt the progression of keratoconus. In some cases, when the refractive errors are large and the visual acuity is low, conventional corneal crosslinking may not be sufficient. In these cases it would be desirable with a treatment that both halts the progression and also reduces the refractive errors and improves the quality of vision.

Aims:  The aims of this thesis were to determine whether mechanical compression of the cornea during corneal crosslinking for keratoconus using a sutured rigid contact lens could improve the optical and visual outcomes of the treatment, and also to find methods to evaluate the effect of different corneal crosslinking treatment regimens.

Methods: In a prospective, open, randomized case-control study, 60 eyes of 43 patients with progressive keratoconus, aged 18-28 years, planned for routine corneal crosslinking, and a corresponding age- and sex-matched control group was included. The patients were randomized to conventional corneal crosslinking (CXL; n=30) or corneal crosslinking with mechanical compression of the cornea during the treatment (CRXL; n=30).

Biomicroscopy, autorefractometry, best spectacle corrected visual acuity, axial length measurement, Pentacam^® HR Scheimpflug photography, pachymetry, intraocular pressure measurements and corneal biomechanical assessments were performed before treatment (baseline) and at 1 month and 6 months after the treatment.

One of the articles evaluated and compared the optical and visual outcomes between CXL and CRXL, while the other three articles focused on methods to evaluate treatment effects. In Paper I, the corneal light scattering was manually quantified from Scheimpflug images throughout the corneal thickness at 8 measurements points, 0.0 to 3.0 mm from the corneal centre, in patients treated with CXL. In Paper IV the corneal densitometry (light scattering) was measured with the Pentacam^® HR software, in 4 circular zones around the corneal apex and at 3 different depths of the corneal stroma, in both CXL and CRXL treated corneas. Paper III quantified the biomechanical effects of CXL in vivo.

Results: Corneal light scattering after CXL showed distinctive spatial and temporal profiles and Applanation Resonance Tonometry (ART) -technology demonstrated an increased corneal hysteresis 1 and 6 months after CXL. When comparing the refractive and structural results after CXL and CRXL, CRXL failed to flatten the cornea, and the treatment did not show any benefits to conventional CXL treatment, some variables even indicated an inferior effect. Accordingly, the increase in corneal densitometry was also less pronounced after CRXL.

Conclusions: Analysis of corneal light scattering/densitometry shows tissue changes at the expected treatment location, and may be a relevant variable in evaluating the crosslinking effect. ART -technology is an in vivo method with the potential to assess the increased corneal hysteresis after CXL treatment. By refining the method, ARTmay become a useful tool in the future. Unfortunately, CRXL does not improve the optical and visual outcomes after corneal crosslinking. Possibly, stronger crosslinking would be necessary to stabilize the cornea in a flattened position.