The prevalence of chronic obstructive pulmonary disease in patients with spondyloarthritis compared to the general population in the southernmost region of Sweden: a case-control study.

Spondyloarthritis (SpA) has been associated with comorbidities, e.g., cardiovascular disease. However, little is known about the relation between SpA and chronic obstructive pulmonary disease (COPD). The aim of the study was to compare the prevalence of COPD in SpA to the general population. Patients with prevalent SpA in Skåne, Sweden, on December 31, 2018, were identified based on diagnostic codes in a regional register on primary care, secondary outpatient care and inpatient care. Population-based controls (5 per SpA case) were matched for age, sex and municipality. The base case definition for COPD required at least two prior visits with a registered COPD diagnosis. Stricter definitions included dispensed prescriptions for COPD and a COPD diagnosis made by a specialist in lung medicine. The prevalence of COPD in patients with SpA and controls, overall and stratified by sex and age, and the corresponding prevalence ratios, were estimated. A total of 3571 patients with SpA (51% male, mean age 53 years) were compared to 17,855 matched controls. The prevalence of COPD in patients with SpA was 37.8/1000, with a prevalence ratio compared to controls of 1.03 (95% CI 0.85-1.24). There were no significant differences in COPD prevalence between patients with SpA and controls in men or women, in any of the age groups, or in analyses using stricter definitions of COPD. In this regional study including data from primary care, the prevalence of COPD was not increased in patients with SpA compared to the background population.

Predictors at diagnosis for start of biologic disease-modifying antirheumatic drugs in patients with early rheumatoid arthritis: a cohort study.

OBJECTIVES: To investigate the relation between patient characteristics at rheumatoid arthritis (RA) diagnosis and subsequent initiation of treatment with biologic disease-modifying antirheumatic drugs (bDMARDs) or targeted synthetic DMARDs (tsDMARDs). DESIGN: A retrospective cohort study. SETTING AND PARTICIPANTS: Consecutive patients (N=330) with early RA (symptom duration <12 months) diagnosed at Skåne University Hospital, Malmö/Lund, Sweden, from 2012 to 2016, were included. Data on demographics, education, comorbidities and treatment were obtained from national registers. OUTCOME: The relation between patient characteristics at diagnosis and time to first bDMARD/tsDMARD initiation was analysed using Cox regression models. As a secondary outcome, the relation between characteristics at diagnosis and b/tsDMARD initiation within 3 years was analysed using logistic regression. RESULTS: A total of 330 patients (mean age 59.2 years; SD 16.4) were included. During follow-up, 41% received a bDMARD (never preceded by a tsDMARD). Higher age at diagnosis was associated with a lower probability of starting bDMARD treatment (multivariable-adjusted HR 0.66 per SD; 95% CI 0.56 to 0.78). Anticitrullinated protein antibody (ACPA) positivity and higher tender joint count at diagnosis were also associated with subsequent bDMARD treatment initiation in multivariable analysis. A higher level of formal education and absence of comorbidities predicted start of a bDMARD in crude, but not in age-adjusted, analyses. CONCLUSIONS: Older patients with RA were less likely to start bDMARDs, whereas ACPA-positive patients, and those with extensive joint involvement at diagnosis, were more likely to receive early bDMARD treatment. The impact of age on the subsequent start of bDMARD therapy was not explained by level of education or comorbidities, suggesting that other aspects of age influence treatment decisions in early RA.

Can rheumatologists unequivocally diagnose axial spondyloarthritis in patients with chronic back pain of less than 2 years duration? Primary outcome of the 2-year SPondyloArthritis Caught Early (SPACE) cohort.

OBJECTIVES: To investigate the prevalence of axial spondyloarthritis (axSpA) in patients with chronic back pain (CBP) of less than 2 years (2y) duration referred to the rheumatologist, the development of diagnosis over time, and patient characteristics of those developing definite (d-)axSpA over 2y. METHODS: We analysed the 2y data from SPondyloArthritis Caught Early, a European cohort of patients (<45 years) with CBP (≥3 months, ≤2y) of unknown origin. The diagnostic workup comprised evaluation of clinical SpA features, acute phase reactants, HLA-B27, radiographs and MRI (sacroiliac joints and spine), with repeated assessments. At each visit (baseline, 3 months, 1y and 2y), rheumatologists reported a diagnosis of axSpA or non-axSpA with level of confidence (LoC; 0-not confident at all to 10-very confident). MAIN OUTCOME: axSpA diagnosis with LoC≥7 (d-axSpA) at 2y. RESULTS: In 552 patients with CBP, d-axSpA was diagnosed in 175 (32%) at baseline and 165 (30%) at 2y. Baseline diagnosis remained rather stable: at 2y, baseline d-axSpA was revised in 5% of patients, while 8% 'gained' d-axSpA. Diagnostic uncertainty persisted in 30%. HLA-B27+ and baseline sacroiliitis imaging discriminated best 2y-d-axSpA versus 2y-d-non-axSpA patients. Good response to non-steroidal anti-inflammatory drugs and MRI-sacroiliitis most frequently developed over follow-up in patients with a new d-axSpA diagnosis. Of the patients who developed MRI-sacroiliitis, 7/8 were HLA-B27+ and 5/8 male. CONCLUSION: A diagnosis of d-axSpA can be reliably made in nearly one-third of patients with CBP referred to the rheumatologist, but diagnostic uncertainty may persist in 5%-30% after 2y. Repeated assessments yield is modest, but repeating MRI may be worthwhile in male HLA-B27+ patients.

Mortality in patients with psoriatic arthritis in Sweden: a nationwide, population-based cohort study.

OBJECTIVES: To compare all-cause mortality and causes of death between patients with psoriatic arthritis (PsA) and the general population in Sweden. METHODS: Adults with at least one main PsA diagnosis (International Classification of Diseases-10: L40.5/M07.0-M07.3) from outpatient rheumatology/internal medicine departments 2001-2017 were identified from the National Patient Register. Each case was matched to five population comparator-subjects on sex/county/age at the case's first arthritis diagnosis. Follow-up ran from 1 January 2007, or from first PsA diagnosis thereafter, until death, emigration or 31 December 2018. Mortality was assessed overall, and stratified by sex and duration since diagnosis (diagnosis before/after 1 January 2007), using matched Cox proportional hazard regression (excluding/including adjustments for comorbidity) or Breslow test, as appropriate. Incidence rate ratios (IRR) of death, overall and stratified by sex/duration since diagnosis/age, as well as causes of death in PsA cases and comparator-subjects were also described. RESULTS: All-cause mortality was elevated in PsA (HR: 1.11 (95% CI: 1.07 to 1.16); IRR: 1.18 (95% CI: 1.13 to 1.22)), mainly driven by increased risks in women (HR: 1.23 (95% CI: 1.16 to 1.30)) and cases with longer time since diagnosis (HR: 1.18 (95% CI: 1.12 to 1.25)). IRR of death were significantly increased for all ages except below 40 years, with the numerically highest point-estimates for ages 40-59 years. When adjusted for comorbidity, however, the elevated mortality risk in PsA disappeared. Causes of death were similar among PsA cases/comparator-subjects, with cardiovascular disease and malignancy as the leading causes. CONCLUSIONS: Mortality risk in PsA in Sweden was about 10% higher than in the general population, driven by excess comorbidity and with increased risks mainly in women and patients with longer disease duration.

Methotrexate treatment in early psoriatic arthritis in comparison to rheumatoid arthritis: an observational nationwide study.

INTRODUCTION: We aimed to compare the proportions of patients with newly diagnosed psoriatic arthritis (PsA) and rheumatoid arthritis (RA) remaining on methotrexate (regardless of other disease-modifying antirheumatic drug (DMARD)-changes), and proportions not having started another DMARD (regardless of methotrexate discontinuation), within 2 years of starting methotrexate, as well as methotrexate effectiveness. METHODS: Patients with DMARD-naïve, newly diagnosed PsA, starting methotrexate 2011-2019, were identified from high-quality national Swedish registers and matched 1:1 to comparable patients with RA. Proportions remaining on methotrexate and not starting another DMARD were calculated. For patients with disease activity data at baseline and 6 months, response to methotrexate monotherapy was compared through logistic regression, applying non-responder imputation. RESULTS: In total, 3642/3642 patients with PsA/RA were included. Baseline patient-reported pain and global health were similar, whereas patients with RA had higher 28-joint scores and evaluator-assessed disease activity. Two years after methotrexate start, 71% of PsA vs 76% of patients with RA remained on methotrexate, 66% vs 60% had not started any other DMARD, and 77% vs 74% had not started specifically a biological or targeted synthetic DMARD. At 6 months, the proportions of patients with PsA versus RA achieving pain-scores ≤15 mm were 26% vs 36%; global health ≤20 mm: 32% vs 42%; evaluator-assessed 'remission': 20% vs 27%, with corresponding adjusted ORs (PsA vs RA) of 0.63 (95% CI 0.47 to 0.85); 0.57 (95% CI 0.42 to 0.76) and 0.54 (95% CI 0.39 to 0.75). DISCUSSION: In Swedish clinical practice, methotrexate use is similar in PsA and RA, both regarding initiation of other DMARDs and methotrexate retention. On a group level, disease activity improved during methotrexate monotherapy in both diseases, although more so in RA.

The National Prevalence of Clinically Diagnosed Psoriatic Arthritis in Sweden in 2017.

OBJECTIVE: Psoriatic arthritis (PsA) prevalence estimates vary across studies; studies based on national data are few. We aimed to estimate the prevalence of clinically diagnosed PsA in Sweden in 2017, overall and stratified by sex, age, education, and geography, and to quantify disease-modifying antirheumatic drug (DMARD) use among those in contact with specialized rheumatology care between 2015 and 2017. METHODS: Individuals who were 18 to 79 years of age, alive and residing in Sweden on December 31, 2017, and had a prior PsA diagnosis were identified from the National Patient Register (NPR) and/or the Swedish Rheumatology Quality Register (SRQ). PsA prevalence was estimated according to a base case (BC) definition (ie, ≥ 1 main PsA International Classification of Diseases code from rheumatology or internal medicine departments in the NPR or a PsA diagnosis in the SRQ), according to 4 sensitivity analysis definitions, and for those seen in specialized rheumatology care between 2015 and 2017. In the latter group, DMARD use during 2017 was also assessed. Data for stratifications were retrieved from national registers. RESULTS: The crude national prevalence of PsA for adults, aged 18 to 79 years, was estimated at 0.39%, according to the BC definition; 0.34% after accounting for diagnostic misclassification; and 0.32% to 0.50% across all sensitivity analyses. The prevalence was lower in males and in those with a higher level of education. The prevalence for those seen in specialized rheumatology care between 2015 and 2017 was estimated at 0.24%. During 2017, 32% of patients in this population received biologic or targeted synthetic DMARDs, and 41% received conventional synthetic DMARDs only. CONCLUSION: The prevalence of clinically diagnosed PsA in adults, aged 18 to 79 years, in Sweden in 2017 was around 0.35%. Among PsA cases in recent contact with specialized rheumatology care, almost three-fourths received DMARD therapy in 2017.

Measuring quality of life of patients with axial spondyloarthritis for economic evaluation.

OBJECTIVES: To estimate the relationship between EQ5D (three levels, UK version) and the Ankylosing Spondylitis Disease Activity Score (ASDAS) for use in the economic evaluation of health technologies for people with axial spondyloarthritis (axSpA). To compare against the relationship with the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI). METHODS: An electronic, prospective, Portuguese, nationwide, rheumatic disease register (Reuma.pt) provided data on 1140 patients (5483 observations) with a confirmed diagnosis of axSpA. We estimated models of EQ5D as a function of ASDAS, alone or in combination with measures of functional impairment, using bespoke mixture models which reflect the complex distributional features of EQ5D. The SPondyloArthritis Caught Early cohort provided data from 344 patients (1405 observations) in four European countries and was used for validation. A previously published model of BASDAI/Bath Ankylosing Spondylitis Functional Index (BASFI) was also used to generate predicted EQ5D scores and model performance compared. RESULTS: A non-linear relationship exists between EQ5D from ASDAS. The final model included ASDAS, ASDAS squared, age and age squared and demonstrated close fit in both datasets except where data were sparse for patients with very high levels of disease activity (ASDAS >4). This finding held in the validation dataset. Models that included BASFI improved model fit. The ASDAS based models fit the data marginally less well than models using BASDAI. CONCLUSIONS: Mapping models linking ASDAS to EQ5D allow results from clinical studies to be used in economic evaluation of health technologies with confidence. There is some loss of information compared with BASDAI but this has only a marginal impact.

Lifestyle Factors and Disease Activity Over Time in Early Axial Spondyloarthritis: The SPondyloArthritis Caught Early (SPACE) Cohort.

OBJECTIVE: Our aim was to study the importance of baseline BMI, smoking, and alcohol consumption (AC) for disease activity (DA) over 1 year in early axial spondyloarthritis (axSpA), stratified by sex. METHODS: In the SPondyloArthritis Caught Early cohort (patients with chronic back pain onset at age < 45 yrs, with pain for ≥ 3 months and ≤ 2 yrs), the Ankylosing Spondylitis Disease Activity Score (ASDAS) was recorded at inclusion, 3, and 12 months. All patients included in the analysis had axSpA based on a high physician's level of confidence at baseline. Differences in ASDAS over 1 year by BMI (normal < 25 kg/m2, overweight 25-29.9 kg/m2, and obese ≥ 30 kg/m2), smoking history (never/previous/current), and AC (none, 0.1-2 units/week, 3-5 units/week, and ≥ 6 units/week) at baseline were estimated using mixed linear regression models. RESULTS: There were 344 subjects (mean age of 30.3 yrs; 49.4% men). In women, obesity was associated with 0.60 (95% CI 0.28-0.91) higher ASDAS compared to normal BMI. In both sexes, AC tended to be associated with lower DA over 1 year, with a significant association only in women with the highest AC (mean difference of -0.55, 95% CI -1.05 to -0.04). Smoking was associated with higher ASDAS over 1 year compared to never smoking in both sexes, although the difference reached statistical significance only in female former smokers. Results were similar in multivariable analysis, adjusted for all lifestyle factors and other confounders. CONCLUSION: In early axSpA, BMI and smoking are associated with higher DA over 1 year, and AC with lower DA. The magnitude of the modest associations may differ between men and women.

Incidence of extra-articular manifestations in ankylosing spondylitis, psoriatic arthritis and undifferentiated spondyloarthritis: results from a national register-based cohort study.

OBJECTIVES: To estimate the incidence and strength of association of extra-articular manifestations [EAMs, here: anterior uveitis (AU), IBD and psoriasis] in patients with AS, undifferentiated SpA (uSpA) and PsA, compared with controls. METHODS: Three mutually exclusive cohorts of patients aged 18-69 years with AS (n = 8517), uSpA (n = 10 245) and PsA (n = 22 667) were identified in the Swedish National Patient Register 2001-2015. Age-, sex- and geography-matched controls were identified from the Swedish Population Register. Follow-up began 1 January 2006, or six months after the first SpA diagnosis, whichever occurred later, and ended at the first date of the EAM under study, death, emigration, 70 years of age, and 31 December 2016. Incidence rates (IRs) and incidence rate ratios were calculated for each EAM, and stratified by sex and age. RESULTS: Incidence rate ratios for incident AU, IBD and psoriasis were significantly increased in AS (20.2, 6.2, 2.5), uSpA (13.6, 5.7, 3.8) and PsA (2.5, 2.3, n.a) vs controls. Men with AS and uSpA had significantly higher IRs per 1000 person-years at risk for incident AU than women with AS (IR 15.8 vs 11.2) and uSpA (IR 10.1 vs 6.0), whereas no such sex difference was demonstrated in PsA or for the other EAMs. CONCLUSIONS: AU, followed by IBD and psoriasis, is the EAM most strongly associated with AS and uSpA. Among the SpA subtypes, AS and uSpA display a largely similar pattern of EAMs, whereas PsA has a considerably weaker association with AU and IBD.

Risk of cardiac rhythm disturbances and aortic regurgitation in different spondyloarthritis subtypes in comparison with general population: a register-based study from Sweden.

OBJECTIVES: To describe the incidence of atrioventricular (AV) block II-III, atrial fibrillation (AF), pacemaker implantation (PM) and aortic regurgitation in patients with ankylosing spondylitis (AS), undifferentiated spondyloarthritis (uSpA) and psoriatic arthritis (PsA) compared with the general population (GP) and with each other. METHODS: A prospective nationwide study with cohorts of patients with AS (n=6448), PsA (n=16 063) and uSpA (n=5190) and a GP (n=2 66 435) cohort, identified in 2001-2009 in the Swedish National Patient and Population registers. Follow-up began on 1 January 2006 and ended at event, death, emigration or 31 December 2012. Age-standardised and sex-standardised incidence rates and hazard ratios (HRs) were calculated. RESULTS: The highest incidence rates were noted for AF (5.5-7.4 events per 1000 person-years), followed by PM (1.0-2.0 events per 1000 person-years). HRs for AV block, AF, PM and aortic regurgitation were significantly increased in AS (HRs 2.3, 1.3, 2.1 and 1.9), uSpA (HRs 2.9, 1.3, 1.9 and 2.0) and PsA (HRs 1.5, 1.5, 1.6 and 1.8) compared with the GP cohort. The highest HRs were seen for AV block in male uSpA (HR 4.2) and AS (HR 2.5) compared with GP. Compared with PsA, significantly increased HRs were noted for PM (HR 1.5) in AS and for AV block (HR 1.8) in uSpA. CONCLUSIONS: Patients with SpA are at increased risk of aortic regurgitation, cardiac rhythm disturbances and, as a probable consequence, also PM. Particularly for AF, the most common arrhythmia, increased caution is warranted, whereas AV block should be looked for especially in men with AS or uSpA.

Are ankylosing spondylitis, psoriatic arthritis and undifferentiated spondyloarthritis associated with an increased risk of cardiovascular events? A prospective nationwide population-based cohort study.

BACKGROUND: To investigate the risk of first-time acute coronary syndrome (ACS), stroke and venous thromboembolism (VTE) in patients with ankylosing spondylitis (AS), psoriatic arthritis (PsA) and undifferentiated spondyloarthritis (uSpA), compared to each other and to the general population (GP). METHODS: This is a prospective nationwide cohort study. Cohorts with AS (n = 6448), PsA (n = 16,063) and uSpA (n = 5190) patients and a GP (n = 266,435) cohort, were identified 2001-2009 in the Swedish National Patient and Population registers. The follow-up began 1 January 2006, or 6 months after the first registered spondyloarthritis (SpA) diagnosis thereafter, and ended at ACS/stroke/VTE event, death, emigration or 31 December 2012. Crude and age- and sex-standardized incidence rates (SIRs) and hazard ratios (HRs) were calculated for incident ACS, stroke or VTE, respectively. RESULTS: Standardized to the GP cohort, SIRs for ACS were 4.3, 5.4 and 4.7 events per 1000 person-years at risk in the AS, PsA and uSpA cohort, respectively, compared to 3.2 in the GP cohort. SIRs for stroke were 5.4, 5.9 and 5.7 events per 1000 person-years at risk in the AS, PsA and uSpA cohort compared to 4.7 in the GP cohort. Corresponding SIRs for VTE were 3.6, 3.2 and 3.5 events per 1000 person-years at risk compared to 2.2 in the GP cohort. Age-and sex-adjusted HRs (95% CI) for ACS events were significantly increased in AS (1.54 (1.31-1.82)), PsA (1.76 (1.59-1.95)) and uSpA (1.36 (1.05-1.76)) compared to GP. Age-adjusted HRs for ACS was significantly decreased in female AS patients (0.59 (0.37-0.97)) compared to female PsA patients. Age-and sex-adjusted HRs for stroke events were significantly increased in AS (1.25 (1.06-1.48)) and PsA (1.34 (1.22-1.48)), and nonsignificantly increased in uSpA (1.16 (0.91-1.47)) compared to GP. For VTE the age-and sex-adjusted HRs for AS, PsA and uSpA were equally and significantly increased with about 50% compared to GP. CONCLUSIONS: Patients with AS, PsA and uSpA are at increased risk for ACS and stroke events, which emphasizes the importance of identification of and intervention against cardiovascular risk factors in SpA patients. Increased alertness for VTE is warranted in patients with SpA.

Childhood hospitalisation with infections and later development of ankylosing spondylitis: a national case-control study.

BACKGROUND: The role of environmental exposures in the pathogenesis of ankylosing spondylitis (AS) remains unclear. In particular, two types of exposures have been suspected to play a role: mechanical stress and infections. The objective of this case-control study was to determine if childhood infections are associated with later development of AS. METHODS: The cases with AS were identified through the Swedish national outpatient specialised-care register, based on having been given at least one AS diagnosis in the register between 2001 and 2010. Five controls per case were identified in the Swedish population register, matched at the time-point of the index case's first spondyloarthritis diagnosis on sex, birth year, and county. All cases/controls matched prior to the age of 17 years were excluded, as well as all cases/controls given a diagnosis of reactive arthritis or juvenile arthritis at any time point, or any other diagnosis of a rheumatic disease, psoriasis, iridocyclitis, or inflammatory bowel disease before the time-point of matching. All events of hospitalisation with an infection before the age of 17 years were retrieved from the register, and categorised according to the focus of the infection. Odds ratios (ORs) and confidence intervals (CIs) were determined through conditional logistic regression analyses. RESULTS: Of the 2453 cases with AS and 10,257 controls, 17.4 % of the cases and 16.3 % of the controls had been hospitalised with an infection before the age of 17 years (OR 1.08, 95 % CI 0.96-1.22). Appendicitis (1.5 % cases; 2.5 % controls; OR 0.59, 95 % CI 0.41-0.83), respiratory tract infections (cases 11.2 %; controls 9.2 %; OR 1.24, 95 % CI 1.07-1.44) and, in particular, tonsillitis (cases 3.7 %; controls 2.8 %; OR 1.31, 95 % CI 1.03-1.67) were associated with AS. There were no associations between AS and any other type of infection, and the point estimates were similar in several sensitivity analyses. CONCLUSIONS: Childhood appendicitis was associated with a decreased risk, whereas respiratory tract infections were associated with an increased risk for later development of AS. These findings support a possible relationship between childhood infections and later development of AS, although the study is limited to infections resulting in inpatient care.

Perinatal characteristics, older siblings, and risk of ankylosing spondylitis: a case-control study based on national registers.

BACKGROUND: The effect of circumstances and exposures early in life on the risk of developing ankylosing spondylitis (AS) is largely unknown. The purpose of this study was to determine whether perinatal characteristics predict development of AS. METHODS: AS cases (n = 1960; 59 % men) were defined as listed with a diagnosis of AS at least once in the Swedish National Patient Register and registered in the Swedish Medical Birth Register (born ≥1973). Population controls were retrieved from the Swedish Population Register (n = 8378; mean 4.3 controls/case), matched on birth year, sex and county. Odds ratios (OR) for developing AS were determined through conditional logistic regression, with regard to: birth weight, birth order, season of birth, maternal age, gestational length, size for gestational age, type of birth, mode of delivery, congenital malformations, mothers' country of birth, mothers' civil status and size of delivery unit. RESULTS: In the univariate analyses statistically significant increases in risk for developing AS were observed for having older siblings (OR 1.18; 95 % Cl 1.06-1.30). No association was observed for the remainder of analysed exposures, although there was a weak association with birth weight below 3000 g (OR 1.19; 95 % CI 1.04-1.37), though not for "low birth weight" <2500 g (OR 0.90; 95 % CI 0.70-1.16). The increase in risk associated with having older siblings was consistent in a multivariate analysis adjusting for possible confounders (OR 1.23; 95 % Cl 1.09-1.39). The direction and magnitude of the point estimates were also consistent in several sensitivity analyses and when stratifying by sex. CONCLUSIONS: Having older siblings was associated with an increased risk for developing AS. These results need to be repeated and confirmed in other cohorts.

Mortality in ankylosing spondylitis: results from a nationwide population-based study.

OBJECTIVES: Information on mortality in ankylosing spondylitis (AS) is scarce. Our study therefore aimed to assess: (1) mortality in AS versus the general population, and (2) predictors of death in the AS population. METHODS: Nationwide cohorts of patients with AS diagnosed at rheumatology or internal medicine outpatient clinics (n=8600) and age-matched, sex-matched and county-matched general population comparators (n=40 460) were identified from the National Patient Register and the census register, respectively. The follow-up period began on 1 January 2006 or at the first date of registered diagnosis thereafter and extended until death, emigration or 31 December 2012, whichever occurred first. Socioeconomic variables, AS-related clinical manifestations, joint surgery, comorbidities and medication were identified from other national registers. Cox regression models were used to determine mortality and predictors for death in the AS cohort. RESULTS: There were 496 deaths in the AS cohort and 1533 deaths in the control cohort resulting in an age-adjusted and sex-adjusted HR of 1.60 (95% CI 1.44 to 1.77), with increased mortality for men (age-adjusted HR=1.53, 95% CI 1.36 to 1.72) and women (age-adjusted HR=1.83, 95% CI 1.50 to 2.22). Within the AS cohort, statistically significant predictors for death were a lower level of education, general comorbidities (diabetes, infections, cardiovascular, pulmonary and malignant diseases) and previous hip replacement surgery. CONCLUSIONS: Mortality was increased for male and female patients with AS. Predictors of death within the AS cohort included socioeconomic status, general comorbidities and hip replacement surgery.

The prevalence of clinically diagnosed ankylosing spondylitis and its clinical manifestations: a nationwide register study.

INTRODUCTION: Prevalence estimates of ankylosing spondylitis vary considerably, and there are few nationwide estimates. The present study aimed to describe the national prevalence of clinically diagnosed ankylosing spondylitis in Sweden, stratified according to age, sex, geographical, and socio-economic factors, and according to subgroups with ankylosing spondylitis-related clinical manifestations and pharmacological treatment. METHODS: All individuals diagnosed with ankylosing spondylitis according to the World Health Organization International Classification of Disease codes, between 1967 and 2009, were identified from the National Patient Register. Data regarding disease manifestations, patient demographics, level of education, pharmacological treatment, and geographical region were retrieved from the National Patient Register and other national registers. RESULTS: A total of 11,030 cases with an ankylosing spondylitis diagnosis (alive, living in Sweden, and 16 to 64 years old in December 2009) were identified in the National Patient Register, giving a point prevalence of 0.18% in 2009. The prevalence was higher in northern Sweden, and lower in those with a higher level of education. Men had a higher prevalence of ankylosing spondylitis (0.23% versus 0.14%, P < 0.001), a higher frequency of anterior uveitis (25.5% versus 20.0%, P < 0.001) and were more likely to receive tumor necrosis factor inhibitors than women (15.6% versus 11.8% in 2009, P < 0.001). Women were more likely than men to have peripheral arthritis (21.7% versus 15.3%, P < 0.001), psoriasis (8.0% versus 6.9%, P = 0.03), and treatment with oral corticosteroids (14.0% versus 10.4% in 2009, P < 0.001). CONCLUSION: This nationwide, register-based study demonstrated a prevalence of clinically diagnosed ankylosing spondylitis of 0.18%. It revealed phenotypical and treatment differences between the sexes, as well as geographical and socio-economic differences in disease prevalence.

The prevalence of moderate to severe radiographic sacroiliitis and the correlation with health status in elderly Swedish men--the MrOS study.

BACKGROUND: Ankylosing Spondylitis (AS) is a chronic inflammatory disease with onset in young adults, but little is known about the prevalence in older age groups. Furthermore, there is very limited information of health status of elderly patients with AS. Our objective was to estimate the prevalence of moderate to severe radiographic sacroiliitis in elderly men and its impact on health. METHODS: A cross-sectional, population-based survey, that included 1005 men aged 69-81 years old, with the primary aim to study risk factors for osteoporosis (MrOS), was used. X-rays of the pelvis and spine were done for the whole population and then examined by two readers. The prevalences of grade 3-4 sacroiliitis, syndesmophytes and spondylophytes were ascertained. Using a self-administered questionnaire, information was obtained on physical activity (PASE), functional status (IADL items), health related quality of life - QoL (SF-12) and back pain (pain question, Quebec Pain Disability Scale items). RESULTS: Fourteen cases with grade 3-4 sacroiliitis were identified, corresponding to a prevalence of 1.4% (95%CI: 0.7-2.4). Eight of the patients with sacroiliitis had both AS-typical and degenerative changes in the spine, 4 had only degenerative changes and 2 had only AS-related changes. There were no statistically significant differences between those with and without radiographic sacroiliitis regarding demographics, anthropometric measures, smoking status or health status, reflected by measures on physical activity, functional status, health related QoL and back pain. CONCLUSIONS: The prevalence of moderate to severe radiographic sacroiliitis was estimated to be 1.4% among elderly men in Sweden. Self-reported health was only slightly different in those with sacroiliitis, suggesting that the relative impact of AS is modest in this age group.

Sustained clinical response and high infliximab survival in psoriatic arthritis patients: a 3-year long-term study.

OBJECTIVE: To investigate the efficacy, toxicity, and survival of infliximab in patients with psoriatic arthritis (PsA). METHODS: Thirty-two patients with PsA, refractory to at least 2 disease-modifying antirheumatic drugs, were included in this prospective, open-label, uncontrolled study. All had active disease, defined as having a tender or swollen joint count > or =6, Psoriasis Area and Severity Index (PASI) scores > or =10, and erythrocyte sedimentation rate > or =28 mm Hg/h, or C-reactive protein > or =10 mg/L. The primary endpoints were the percentage of patients who achieved the Psoriatic Arthritis Response criteria (PsARC) and the improvement of PASI. Patients were treated with infliximab (5 mg/kg) at weeks 0, 2, 6, and every 8 weeks thereafter for a period of 3 years. Data concerning infliximab efficacy, tolerability, concomitant therapy, adverse events, and drug discontinuation were recorded. The clinical response according to the American College of Rheumatology (ACR) criteria as well as the disease activity for 28 joint indices score (DAS-28) were also recorded. RESULTS: After the third year of treatment, PsARC was achieved by 23/32 of patients, PASI 70 by 24/32, and PASI 90 by 23/32. A significant improvement of ACR and DAS-28 was noted. Clinical improvement was associated with a reduction of acute phase reactants. Eight patients withdrew from the study primarily for acute allergic reactions. After the first year, infliximab survival was 84%, while after the second year, it was 75%, which was maintained throughout the third year of treatment. CONCLUSION: Infliximab was effective, safe, and well tolerated in patients with PsA. The clinical response was maintained for a period of 3 years with high infliximab survival.