Reduced sleep quality is highly prevalent and associated with physical function and cardiorespiratory fitness in patients with axial spondyloarthritis: a cross-sectional study.

OBJECTIVES: To assess sleep quality, and its associations with physical function, cardiorespiratory fitness, and spinal mobility, in axial spondyloarthritis (axSpA) patients. METHOD: Baseline data from the Exercise for Spondyloarthritis trial were used. Assessments included [Pittsburgh Sleep Quality Index (PSQI), 0-21, 21 = worst], performance-based physical function [Ankylosing Spondylitis Performance Index (ASPI), seconds, higher = worse], patient-reported physical function [Bath Ankylosing Spondylitis Functional Index (BASFI), 0-10, 10 = worst], cardiorespiratory fitness [peak oxygen uptake (VO2peak), mL/kg/min, lower = worse], and spinal mobility [Bath Ankylosing Spondylitis Metrology Index (BASMI), 0-10, 10 = worst]. Associations were examined in separate models using multiple linear regression. RESULTS: Ninety-nine patients with axSpA were included, 53% female, mean age 46 years, and 72% with high disease activity (ASDAS-C-reactive protein ≥ 2.1), of whom 84 (85%) had reduced sleep quality. Sleep disturbance was most frequently reported (65%), followed by poor subjective sleep quality (53%), daytime dysfunction (41%), and increased sleep latency (41%). Positive associations were observed between PSQI and ASPI [ß = 0.10, 95% confidence interval (CI) 0.01, 0.19] and PSQI and BASFI (ß = 0.85, 95% CI 0.51, 1.20), and there was an inverse association between PSQI and VO2peak (ß = -0.14, 95% CI -0.27, -0.01), adjusted for age and sex. There was no association between PSQI and BASMI. CONCLUSION: Reduced sleep quality was common in axSpA patients with moderate to high disease activity. Better sleep quality was associated with better physical function and higher cardiorespiratory fitness. There was no association between sleep quality and spinal mobility. TRIAL REGISTRATION: ClinicalTrials.gov NCT02356874.

Comorbidities in the Spondyloarthritis GISEA Cohort: an average treatment effect analysis on patients treated with bDMARDs.

OBJECTIVES: We aimed to investigate the effectiveness of tumour necrosis factor inhibitors (TNFi), anti-interleukin-17 or interleukin-12/23 monoclonal antibodies (anti-IL) on comorbidities in a cohort of patients with spondyloarthritis (SpA), using an average treatment effect (ATE) analysis. METHODS: SpA patients from the multicentre Italian GISEA Registry were divided into groups according to pharmacological exposure: no treatment (G0), TNFi (G1) and non-responders to TNFi switched to anti-IL (G2). In each group, we recorded the prevalence and incidence of infectious, cardiopulmonary, endocrinological, gastrointestinal, oncologic, renal and neurologic comorbidities. Each comorbidity was then fitted for ATE and baseline features were evaluated for importance. RESULTS: The main findings of this study comprising 4458 SpA patients relate to cancer, other gastrointestinal diseases (OGID) and fibromyalgia. ATE showed no increased risk of solid cancer in G1 (0.42 95% CI 0.20-0.85) and G2 (0.26 95% CI 0.08-0.71) vs. G0, with significantly higher incidence in G0 (14.07/1000 patient-years, p=0.0001). Conversely, a significantly higher risk of OGID and fibromyalgia was found in G1 (1.56 95% CI 1.06-2.33; 1.69 95% CI 1.05-2.68, respectively) and G2 (1.91 95% CI 1.05-3.24; 2.13 95% CI 1.14-3.41, respectively) vs. G0. No treatment risk reduction was observed in haematological malignancies, cardiovascular events and endocrinological comorbidities. CONCLUSIONS: Overall, our study confirms the safety of TNFi and anti-IL in SpA patients, albeit with some caveats pertaining to solid cancers, OGID and fibromyalgia. Furthermore, taking into consideration causality with observational data may yield more reliable and relevant clinical information.

Tuberculosis and Nontuberculous Mycobacterial Infections in Patients with Spondyloarthritis: A Population-Based Study.

Background and Objectives: Tuberculosis is caused by Mycobacterium tuberculosis (MTB), while nontuberculous mycobacteria (NTM) encompass a group of mycobacterial species that are distinct from the MTB complex and leprae. Spondyloarthritis (SpA) is a group of chronic inflammatory diseases with shared clinical characteristics and is treated with biological agents; however, their use may elevate the risk of MTB and NTM infections. This study aimed to compare the incidence and risk of MTB and NTM infections in patients with SpA, including ankylosing spondylitis (AS) and psoriatic arthritis (PsA), using a population-based approach. Materials and Methods: This study included 2333 patients with SpA and 9332 age- and sex-matched controls from the Korea National Health Insurance Service-National Sample Cohort database from 2002 to 2019. The patients were identified using the International Classification of Diseases-10 codes for AS, PsA, MTB, and NTM. Results: The results showed that a negligible percentage of patients with SpA developed NTM (0.002%) and MTB (0.016%), with no significant difference in the incidence rate ratio (IRR) compared to controls. Among patients with SpA treated with biologics, the IRRs for NTM and MTB were 5.66 and 3.069, respectively; however, these were not statistically significant. No cases of NTM or MTB infection were reported in female patients with SpA treated with biologics. In both the SpA patient group and the control group, the incidence of MTB was higher in individuals over 60 years old compared to those under 60 years old. Cox proportional hazard analysis revealed a significant adjusted hazard ratio of 1.479 for MTB in patients with SpA after adjusting for age, sex, smoking history, insurance level, and comorbidities. However, this significance was not maintained when biological therapy was further adjusted. Conclusions: Our study indicated that the risks of NTM and MTB infection are not elevated in patients with SpA. Although biological use may potentially increase the risk of MTB infection, it does not lead to a significant increase in incidence rates. Proactive screening for latent tuberculosis and adequate prophylaxis using biologics can effectively manage the risk of NTM and MTB infections.

[Coexistence of familial Mediterranean fever and seronegative spondyloarthritis: peculiarities of the course].

Familial Mediterranean fever (FMF) is an autosomal recessive disease distributed among populations of Mediterranean origin - Armenians, Sephardi Jews, Arabs, Turks. There are numerous clinical observations regarding combination of FMF, as a classical representative of autoinflammatory diseases, with systemic diseases of connective tissue. Seronegative spondyloarthritis (SpA) are the most interesting disorders from this point of view, as far as sacroiliitis - an essential feature of SpA, may also present as a part of joint syndrome in FMF. The main objective of this clinical study was the investigation of the peculiarities of courses of FMF and SpA in case of their coexistence. We studied 126 patients with FMF, SpA and coexistence of both. According to results, patients with the overlap of FMF with SpA had relatively milder course of disease in comparison with each disease separately. Comparative clinical and instrumental characteristics of FMF-associated disorders had shown that in FMF-SpA overlap the symptoms of both diseases are less severe.

The influence of age on the prevalence of inflammatory and structural MRI lesions in the sacroiliac joints of patients with and without axial spondyloarthritis.

OBJECTIVES: To compare the influence of age on inflammatory (bone marrow oedema [BME]) and structural (fat lesions [FL], erosions and ankylosis) MRI lesions in the sacroiliac joints (SIJ) of patients with and without axial spondyloarthritis (axSpA). METHODS: In a retrospective study, SIJ MRI (STIR/T1 sequences) of consecutive patients with chronic back pain diagnosed with axSpA or non-SpA were evaluated based on SIJ quadrants (SIJ-Q). Two blinded readers evaluated BME and structural lesions. Reader agreement was evaluated for prevalence of MRI lesions related to age. RESULTS: MRIs of 309 (175 axSpA, 134 non-SpA) patients were evaluated. Their mean age was 38.5 (11.4) and 43.4 (13.8) years, 67% and 36% were male, CRP was 1.6 (2.4) and 1.1 (2.1) mg/dl and median symptom duration was 48 and 60 months for axSpA and non-SpA, respectively. SIJ-Q with BME and erosions were significantly more frequent in axSpA vs non-SpA patients independent of age, while this difference was seen for FL only in patients ≥50 years. The proportion of patients with ≥1 or ≥3 BME or chronic lesions except for FL increased with age in both groups, and was constantly higher in axSpA vs non-SpA. In univariate analyses, only female sex was significantly associated with more FL. CONCLUSIONS: The proportion of patients with MRI lesions was high in both axSpA and non-SpA patients. However, the prevalence of BME and erosions was significantly more frequent in patients with axSpA, was independent of age and also allowed for discrimination. FL occurred more frequently only in older age groups and were less reliable for discrimination vs non-SpA patients.

Prevalence of undiagnosed axial spondyloarthritis in inflammatory bowel disease patients with chronic back pain: secondary care cross-sectional study.

OBJECTIVE: To elucidate the prevalence of undiagnosed rheumatology-verified diagnosis of axial spondyloarthritis (RVD-axSpA) in patients attending routine secondary care IBD clinics with chronic back pain. METHODS: Screening questionnaires were sent to consecutive patients attending IBD clinics in a university teaching hospital. Patients fulling the eligibility criteria (gastroenterologist-verified diagnosis, 18-80 years old, biologic therapy naive, no previous diagnosis of axSpA); and a moderate diagnostic probability of axSpA [self-reported chronic back pain (CBP) >3 months, onset <45 years] were invited for rheumatology assessment. This included medical review, physical examination, patient reported outcome measures, human leucocyte antigen B27, C-reactive protein, pelvic radiograph and axSpA protocol magnetic resonance imaging. A diagnosis of RVD-axSpA was made by a panel of rheumatologists. RESULTS: Of the 470 patients approached, 91 had self-reported CBP >3 months, onset <45 years, of whom 82 were eligible for clinical assessment. The prevalence of undiagnosed RVD-axSpA in patients attending IBD clinics in a secondary care setting, with self-reported CBP, onset <45 years is estimated at 5% (95% CI 1.3, 12.0) with a mean symptom duration of 12 (s.d. 12.4) years. CONCLUSION: There is a significant hidden disease burden of axSpA among IBD patients. Appropriate identification and referral from gastroenterology is needed to potentially shorten the delay to diagnosis and allow access to appropriate therapy.

Spondyloarthritis and Sarcopenia: Prevalence of Probable Sarcopenia and its Impact on Disease Burden: The Saspar Study.

To evaluate the prevalence of probable, confirmed, and severe sarcopenia in spondyloarthritis (SpA), according to the European Working Group on Sarcopenia in Older People 2019 (EWGSOP2) definition. A total of 103 patients (51% women) with SpA, mean age 47.1 ± 13.7 years, were included and compared to 103 age- and sex-matched controls. Grip strength was measured by dynamometry. Body composition was assessed by whole-body densitometry. In SpA patients gait speed was measured by the 4-m-distance walk test and quality of life was evaluated with a specific health-related questionnaire for sarcopenia (SaRQoL®). Twenty-two SpA patients (21%) versus 7 controls (7%) had a low grip strength, i.e., probable sarcopenia (p < 0.01), 15 SpA (15%) patients and 7 controls (7%) had low Skeletal Muscle mass Index (SMI) (ns), respectively, and 5 and 2% of SpA patients and controls had low grip strength and low SMI, i.e., confirmed sarcopenia (ns). All the sarcopenic SpA patients had a low gait speed, i.e., severe sarcopenia. Finally, probable sarcopenic SpA patients had significantly higher C-Reactive Protein (CRP, p < 0.001) and Bath Ankylosing Spondylitis Disease Activity Index (BASDAI score, p < 0.01), lower gait speed (p < 0.001), and SarQoL® score (p < 0.001) than SpA patients with normal grip strength. According to EWGSOP2 definition, the prevalence of probable sarcopenia was significantly higher in SpA patients compared to controls. Probable sarcopenia was associated with higher inflammation and disease activity, impaired muscle performance, and quality of life. These results suggest that muscle strength may be a salient hallmark in SpA.

Development and validation of a screening tool for SPondyloArthritis Screening in Sub-Saharan Africa: SpASSS questionnaire.

OBJECTIVE: To develop and validate a screening tool to identify patients with a high likelihood for Spondyloarthritis (SpA) in the Democratic Republic of the Congo (DR Congo). METHODS: The development of the SpA Screening questionnaire in Sub Saharian Africa (SpASSS) questionnaire followed 3 steps: The item generation was carried out by a systematic literature review according to the PRISMA guidelines on the clinical manifestations of SpA, interviewing clinical experts and the classification criteria for Spondyloarthritis. The candidate questions were tested in a population of 50 consecutive patients with confirmed diagnosis of spondyloarthritis, in a control population of rheumatic disease excluding SpA and in a group of 200 non-rheumatic participants, randomly chosen in the general population for question reduction and validation. Descriptive statistical analyses were performed to assess socio-demographic characteristics and response distribution for each item. Their diagnostic performance was investigated using ROC curves. For validation, principal component analysis was performed using factor analysis. Referral strategy score for SpA was determined by adjusted Cronbach's alpha coefficient. RESULTS: Mean ± SD age of SpA cases was 41.8 ± 14.4 years, 56% were men compared to diseased controls 60.0 ± 12.5 years, 28.7% men (p < 0.001). 14/20 items showed a statistically significant difference (p < 0.05) between SpA cases and control groups. All items were factorable and 6 components were identified. Only the two first components (C1 with 8 items, C2 with 3 items) showed a significant threshold for reliability in detection of suspected SpA with a Cronbach's alpha of 0.830 and 0.708. All validated items of these two components showed the global reliability threshold with α-adjusted Cronbach calculated at 66.9%. The performance for correctly screening SpA was demonstrated with an area under the curve of 0.938 (0.884-0.991) and 0.794 (0.728-0.861) for C1 and C2 respectively. CONCLUSIONS: This validation and item reduction of the SpASSS questionnaire for SpA might identify patients to refer for case ascertainment and will help conducting future epidemiological and clinical studies in the DR Congo. STRENGTHS AND LIMITATIONS OF THIS STUDY: • To the best of our knowledge, this is the first study in Sub-Saharan Africa based on local data to develop a screening tool for SpA in the population for epidemiological and clinical use. • Referral strategies based on context-specific data are necessary to provide accurate case definition and epidemiological data, thus reducing methodological bias. • In the SpA group, no discrimination was made regarding SpA subtypes, disease duration, activity and severity.

Increase in axial spondyloarthritis diagnoses after the introduction of the ASAS criteria: a systematic review.

To explore the proportion of axial spondyloarthritis (axSpA) and psoriatic arthritis (PsA) diagnoses within all newly referred patients visiting rheumatology outpatient clinics. And more specifically, to analyze whether there is an effect of the introduction of the ASAS and CASPAR classification criteria for axSpA and PsA. We systematically searched Embase, Medline Ovid, Cochrane Central and Web of Science from database inception to November 2022. Articles that investigated new onsets of axSpA and PsA in adults from rheumatology clinics were included. In total, 170 out of 7139 studies were found eligible for full-text review, after which 33 unique studies were included. Seventeen studies reported new onsets of axSpA, and 20 studies of PsA. The pooled proportion of axSpA within all newly referred patients was 19% (95% CI 15-23%) and 18% (95% CI 14-22%) for PsA. The proportion of axSpA before 2009 was 3% (95% CI 0-6%) and increased up to 21% (95% CI 14-28%) after 2009. For PsA, limited data were available in order to analyze the proportions of PsA before 2006. Overall, heterogeneity was high (I2 > 95%, p < 0.001) that was most likely caused by geographical area, study design, setting and use of different referral strategies. The pooled proportion of axSpA and PsA among patients referred to the rheumatology outpatient clinic was 19 and 18%, respectively. Although the proportion of diagnosed axSpA patients seemed to increase after the introduction of the ASAS criteria, due to the large heterogeneity our findings should be interpreted with caution.

Higher frequency but similar recurrence rate of uveitis episodes in axial spondylarthritis compared to psoriatic arthritis. A multicentre retrospective study.

BACKGROUND/OBJECTIVE: Data on risk factors predicting uveitis development in spondyloarthritis (SpA) is scarce. Our aim was to examine associations between demographic, clinical and/or laboratory characteristics of SpA with the occurrence and the course of uveitis, including ocular damage and recurrence rate. METHODS: Characteristics (at disease diagnosis and ever-present) from axSpA and Psoriatic arthritis (PsA) patients followed in 3 tertiary rheumatology-clinics were retrospectively recorded. Comparisons were made between patients with and without uveitis, as well as between those with uveitis-rate [episodes/year] above the median uveitis-rate in the whole cohort ("recurrent"-uveitis) and the remaining uveitis patients ("non-recurrent uveitis"). In multivariable models, age, gender and variables significantly different in univariate analyses were included. RESULTS: 264 axSpA and 369 PsA patients were enrolled. In axSpA, uveitis occurred in 11.7% and was associated with HLA-B27 (OR = 4.15, 95%CI 1.16-14.80, p = 0.028) and ever-present peripheral arthritis (OR = 3.05 (1.10-8.41, p = 0.031). In contrast, uveitis in PsA occurred only in 2.7% of patients and was associated with SpA family-history (OR = 6.35 (1.29-31.27), p = 0.023) axial disease at diagnosis (OR = 5.61 [1.01-28.69], p = 0.038) and disease duration (OR = 1.12 [1.04-1.21], p = 0.004). Median uveitis recurrence rate was comparable between axSpA and PsA (0.205 and 0.285 episodes/year, respectively). No associations were found between recurrent uveitis and demographic/clinical/laboratory characteristics. Ocular damage (e.g. synechiae) was seen in 16.1% of axSpA and 30% of PsA patients, all of them with recurrent uveitis. CONCLUSION: Uveitis occurred more commonly in axSpA than in PsA patients, while uveitis recurrence rate was similar. Permanent ocular damage may occur more often in PsA than axSpA.

Screening for spondyloarthritis in patients with inflammatory bowel diseases.

Inflammatory bowel diseases (IBDs) can be associated with various musculoskeletal (IBD-MSK) manifestations that could be difficult to classify for gastroenterologists. We aimed to evaluate the characteristics of patients with IBD-MSK and the prevalence of spondyloarthritis (SpA). In this observational cross-sectional study, we included patients with IBD-MSK complaints (peripheral or back pain). All patients underwent a standardized rheumatology evaluation including clinical, biological and imaging evaluations (MRI of spine and sacroiliac joints and ultrasonography of enthesis). We included 183 IBD patients (60.7% women; median [interquartile range] age 45 [36-56] years); 159 (87%) had joint pain. In 43 (23.5%) and 25/175 (14.3%) patients, enthesis abnormalities were found on ultrasonography and sacroiliitis on MRI, respectively. SpA was diagnosed in 54 (29.5%) patients. IBD-related arthralgia and degenerative spine disease were diagnosed in 105 (57.4%) and 72 (39.3%) patients. Sixteen (29.6%) SpA patients initiated a new conventional synthetic disease modifying anti-rheumatic drug (DMARD). A biologic DMARD was initiated in 10 patients or changed in 3. More than half of IBD-MSK patients had IBD-related arthralgia, and about one-third had definite SpA. Ultrasonography of enthesis and systematic MRI of sacroiliac joints seem useful for SpA classification and differential diagnosis in these patients who often have musculoskeletal pain complaints. Therapeutics were changed in most patients, which highlights the need for a multidisciplinary approach for managing IBD with extra-intestinal symptoms.

Factors Associated With Adverse Outcomes in Uveitis Related to Spondyloarthritis: Development of an Outcome Score (SpA-U).

BACKGROUND: Evaluating the efficacy and refractoriness to treatment and determining factors associated with adverse outcomes in uveitis associated with spondylarthritis (SpA) are complicated by the lack of validated outcome measures. OBJECTIVES: The aims of this study were to develop an outcome score SpA-U in patients with uveitis associated with SpA and to determine factors associated with adverse outcomes in patients with uveitis under systemic treatment. METHODS: The outcome score SpA-U was defined by best-corrected visual acuity, anterior chamber inflammation, macular edema and inflammation of posterior chamber, global assessment, and refractoriness to treatment. Factors associated with adverse outcomes in uveitis were studied using linear regression. For categorical factors, marginal averages and their SEs are displayed together with linear regression coefficients with 95% confidence intervals. For continuous factors, averages and SDs are reported in addition to linear regression coefficients with 95% confidence interval. Two regression coefficients are reported for each variable: unadjusted and adjusted for age at diagnosis and sex. RESULTS: One hundred ninety-seven uveitis outbreaks were included. Sixty-two uveitis outbreaks (31%) were classified as severe, 42 as moderate (21%), and 93 as mild (47%) based on the definition and construction of outcome score. The results of the linear regression model revealed that the uveitis activity was more severe in patients with smoking history ( ß = 0.34), axial and peripheral involvement ( ß = 0.43), Ankylosing Spondylitis Disease Activity Score >2.1 ( ß = 0.45), positive HLA-B27 ( ß = 0.29), female sex ( ß = 0.19), patients with C-reactive protein elevation ( ß = 0.002), and bilateral ocular involvement ( ß = 0.32). At the same time, shorter disease evolution ( ß = -0.02) was associated with less severe uveitis activity. CONCLUSION: We have determined factors associated with adverse outcomes in patients with uveitis associated with SpA by developing an outcome score SpA-U that integrates ocular inflammatory activity, visual acuity, global assessment, and refractoriness to treatment.

The occurrence of multiple treatment switches in axial spondyloarthritis. Results from five Nordic rheumatology registries.

OBJECTIVES: In axial spondyloarthritis (axSpA), switching between multiple biologic or targeted synthetic (b/ts-) DMARDs might indicate difficult-to-treat disease. We aimed to explore the occurrence of multiple switching in routine care axSpA patients using various definitions, and to identify associated clinical characteristics upon start of first b/tsDMARD (baseline). METHODS: Observational cohort study including patients with axSpA starting a first-ever b/tsDMARD 2009-2018 based on data from five biologic registries (Denmark/Sweden/Finland/Norway/Iceland). Comorbidities and extra-articular manifestations were identified through linkage to national registries. Multi-switching was defined in overlapping categories according to b/tsDMARD treatment history: treatment with ≥3, ≥4 or ≥5 b/tsDMARDs during follow-up. We explored the cumulative incidence of patients becoming multi-switchers with ≥3 b/tsDMARDs stratified by calendar-period (2009-2011, 2012-2013, 2014-2015, 2016-2018). In the subgroup of patients starting a first b/tsDMARD 2009-2015, baseline characteristics associated with multi-switching (within 3 years' follow-up) were explored using multiple logistic regression analyses. RESULTS: Among 8398 patients included, 6056 patients (63% male, median age 42 years) started a first b/tsDMARD in 2009-2015, whereof proportions treated with ≥3, ≥4 or ≥5 b/tsDMARDs within 3 years' follow-up were 8%, 3% and 1%, respectively. Calendar-period did not affect the cumulative incidence of multi-switching. Baseline characteristics associated with multi-switching (≥3 b/tsDMARDs) were female gender, shorter disease duration, higher patient global score, comorbidities and having psoriasis but not uveitis. CONCLUSION: In this large Nordic observational cohort of axSpA patients, multiple switching was frequent with no apparent time-trend. Clinical associated factors included gender, but also previous comorbidities and extra-articular manifestations illustrating the ongoing challenge of treating this patient group.

Individual-level and country-level socio-economic factors and health outcomes in spondyloarthritis: analysis of the ASAS-perSpA study.

OBJECTIVES: The aim of this study was to investigate the association between individual-level and country-level socio-economic (SE) factors and health outcomes across SpA phenotypes. METHODS: Patients with axial SpA (axSpA), peripheral SpA (pSpA) or PsA from the ASAS-perSpA study (in 23 countries) were included. The effect of individual-level (age, gender, education and marital status) and country-level [e.g. Gross Domestic Product (GDP)] SE factors on health outcomes [Ankylosing Spondylitis Disease Activity Score (ASDAS) ≥ 2.1, ASDAS, BASFI, fatigue and the Assessment of SpondyloArthritis international Society Health Index (ASAS-HI)] was assessed in mixed-effects models adjusted for potential confounders. Interactions between SE factors and disease phenotype were tested. A mediation analysis was conducted to explore whether the impact of country-level SE factors on ASDAS was mediated through biologic/targeted synthetic (b/ts) DMARD uptake. RESULTS: In total, 4185 patients (61% males, mean age 45) were included (65% axSpA, 25% PsA, 10% pSpA). Female gender [ß= 0.14 (95% CI: 0.06, 0.23)], lower educational level [ß = 0.35 (0.25, 0.45)) and single marital status [ß = 0.09 (0.01, 0.17)] were associated with higher ASDAS. Living in lower GDP countries was also associated with higher ASDAS [ß = 0.39 (0.16, 0.63)], and 7% of this association was mediated by b/tsDMARD uptake. Higher BASFI was similarly associated with female gender, lower education and living alone, without the effect of country-level SE factors. Female gender and lower educational level were associated with worse ASAS-HI, while more fatigue was associated with female gender and higher country-level SE factors [lower GDP, ß = -0.46 (-0.89 to -0.04)]. No differences across disease phenotypes were found. CONCLUSIONS: Our study shows country-driven variations in health outcomes in SpA, independently influenced by individual-level and country-level SE factors and without differences across disease phenotypes.

Age at onset in axial spondyloarthritis around the world: data from the Assessment in SpondyloArthritis international Society Peripheral Involvement in Spondyloarthritis study.

OBJECTIVE: Age at onset is useful in identifying chronic back patients at an increased risk of axial SpA (axSpA). However, the majority of data on which the criterion of age at onset <45 years is based originates from Europe. Therefore it is unknown if this criterion applies in other parts of the world. We aimed to assess the age at onset of axSpA and its relationship with HLA-B27 and gender across the world. METHODS: Analyses were applied to patients from 24 countries across the world with an axSpA diagnosis and known age at onset of axial complaints. Cumulative probability plots were used to display the cumulative distribution of age at onset of axial symptoms. Linear regression models were built to assess the effect of HLA-B27 and gender on age at onset of axial symptoms. RESULTS: Of 2579 axSpA patients, 92% had an age at onset of axial symptoms <45 years, with only small variations across the geographical regions [Asia, n = 574 (94%); Europe and North America, n = 988 (92%); Latin America, n = 246 (89%); Middle East and North Africa, n = 771 (91%)]. Age at onset of axial symptoms was consistently lower in HLA-B27-positive patients {median 25 years [interquartile range (IQR) 19-32] vs 31 [IQR 22-39]} and male patients [median 25 years (IQR 19-33) vs 28 (IQR 21-37)], but in multivariable models an additional statistically significant effect of male gender independent of HLA-B27 was only found in Asia. CONCLUSION: Around the world, the great majority of axSpA patients had an age at onset of axial disease of <45 years, with HLA-B27 and male gender associated with earlier disease onset.

Characteristics of patients with axial spondyloarthritis by geographic regions: PROOF multicountry observational study baseline results.

OBJECTIVES: To compare demographic and clinical characteristics of patients with axial SpA (axSpA) across geographic regions. METHODS: Patients With Axial Spondyloarthritis: Multicountry Registry of Clinical Characteristics (PROOF) is an observational study that enrolled recently diagnosed (≤1 year) axSpA patients fulfilling the Assessment of SpondyloArthritis international Society classification criteria from rheumatology clinical practices in 29 countries across six geographic regions. Demographics and disease-related parameters were collected. Here we present baseline data for patients who were classified as radiographic axSpA (r-axSpA) or non-radiographic axSpA (nr-axSpA) confirmed by central reading. RESULTS: Of the 2170 patients enrolled, 1553 were classified based on central evaluation of sacroiliac radiographs [r-axSpA: 1023 (66%); nr-axSpA: 530 (34%)]. Patients with nr-axSpA had a significantly higher occurrence of enthesitis (40% vs 33%), psoriasis (10% vs 5%) and IBD (4% vs 2%) vs r-axSpA patients. Significant differences in axSpA characteristics were observed between geographic regions. The highest occurrence of peripheral arthritis (60%), enthesitis (52%) and dactylitis (12%) was in Latin America, and the lowest was in Canada (9%, 9% and 2%, respectively). The occurrence of uveitis and psoriasis was highest in Canada (18% and 14%, respectively) and lowest in China (6% and <1%, respectively). IBD was highest in Arabia (21%), and no cases were observed in China. In multivariable analysis adjusted for factors potentially affecting peripheral and extramusculoskeletal manifestations, geographic regions still exhibited significant differences in frequencies of uveitis (P < 0.01), psoriasis (P < 0.0001) and peripheral arthritis (P < 0.0001). CONCLUSION: The multinational PROOF study of axSpA patients showed significant regional differences in peripheral and extramusculoskeletal manifestations of SpA, which could be considered in management guidelines and clinical trials.

How do clinical and socioeconomic factors impact on work disability in early axial spondyloarthritis? Five-year data from the DESIR cohort.

OBJECTIVES: To investigate the impact of clinical and socioeconomic factors on work disability (WD) in early axial spondyloarthritis (axSpA). METHODS: Patients from the DESIR cohort with a clinical diagnosis of axSpA were studied over 5 years. Time to WD and potential baseline and time-varying predictors were explored, with a focus on socioeconomic (including ethnicity, education, job-type, marital/parental status) and clinical (including disease activity, function, mobility) factors. Univariable analyses, collinearity and interaction tests guided subsequent multivariable time-varying Cox survival analyses. RESULTS: From 704 patients eligible for this study, the estimated incidence of WD among those identified as at risk (n = 663, 94%), and across the five years of DESIR, was 0.05 (95% CI 0.03, 0.06) per 1000 person-days. Significant differences in baseline socioeconomic factors, including lower educational status and clinical measures, including worse disease activity, were seen in patients developing WD over follow-up, compared with those who never did. In the main multivariable model, educational status was no longer predictive of WD, whereas the AS disease activity score (ASDAS) and the BASFI were significantly and independently associated with a higher hazard of WD [HR (95%CI) 1.79 (1.27, 2.54) and 1.42 (1.22, 1.65), respectively]. CONCLUSION: WD was an infrequent event in this early axSpA cohort. Nevertheless, clinical factors were among the strongest predictors of WD, over socioeconomic factors, with worse disease activity and function independently associated with a higher hazard of WD. Disease severity remains a strong predictor of adverse work outcome even in early disease, despite substantial advances in therapeutic strategies in axSpA.

Trends in fractures in patients with spondyloarthritis: a nationwide population-based study (TREND-EspA study).

Our aim was to analyze trends in fracture rates in SpA patients over an extended time period. Only an increase of axial fractures, more specifically vertebral fractures, is observed in SpA. PURPOSE: To analyze fracture incidence and trend in patients with spondyloarthritis (SpA) over an extended time period. METHODS: Retrospective observational population-based study with matched cohorts. Data from the Minimum Basic Data Set (MBDS) of Spain were reviewed. All SpA patient hospitalizations reported from 1999 to 2015 (SpA cohort) were analyzed. A control cohort (non-SpA cohort) matched by age, sex, region, and year of hospitalization was recruited. The age and sex-adjusted crude incidence rate was calculated for any fractures (axial and peripheral). Generalized linear models (GLM) were used for trend analysis. Association between fracture type and SpA (and its subtypes) was assessed using unconditional logistic regression models. RESULTS: In the SpA cohort, the age and sex-adjusted rates per 100,000 inhabitants/year of total fracture and different types of fracture were 45.72 any fractures, 17.64 axial, and 28.02 peripheral; 29.42 osteoporotic (12.67 vertebra, 12.29 hip, 1.50 pelvis, 1.82 humerus and 2.09 radius). In the non-SpA cohort, they were 65.79 any, 12.08 axial, 51.52 peripheral; 31.17 osteoporotic (4.94 vertebra, 16.15 hip, 2.29 pelvis, 3.64 humerus, 5.38 radius). Between 1999 and 2015, the trend in incidence rate for total fracture and different types of fracture increased similarly for both cohorts. In the SpA cohort, an increase of axial fractures was found (AOR 1.444; 95%CI 1.297-1.609), and specifically of vertebral fractures (AOR 2.440; 95%CI 2.097-2.839). Other types of fractures did not increase. CONCLUSIONS: Only an increase of axial fractures, more specifically vertebral fractures, is observed in SpA. Trend in incidence is similar in both cohorts.

Diagnosing axial spondyloarthritis by multidiciplinary team conference at 3.5 years' follow-up in a cohort of patients with disease features according to the ASAS criteria.

OBJECTIVES: During the past two decades, magnetic resonance imaging (MRI) has increasingly been used diagnostically in axial spondyloarthritis (axSpA), and in 2009 MRI was introduced in the Assessment of SpondyloArthritis Society (ASAS) classification criteria. In clinical practice, there is a risk of overdiagnosis if MRI findings are not related to clinical and biochemical findings. The aim of this study was to provide an estimate of the prevalence of axSpA in a cohort of clinical patients with low back pain and findings suggestive of axSpA according to ASAS through consensus diagnosis at a multi-disciplinary team (MDT) conference, and to describe the performance of the features included in the ASAS criteria. METHOD: Consensus diagnoses of axSpA at MDT conferences were retrospectively established at 3.5 years' follow-up in a cohort of 84 patients, initially referred with disease features according to the ASAS criteria. Patients were examined clinically regarding spondyloarthritis features, and biochemical tests and MRI of the sacroiliac joints and entire spine were performed at baseline and after a mean of 3.5 years. RESULTS: According to the MDT consensus, 25 patients (30%) of the total cohort had axSpA at follow-up; 40% of individuals who fulfilled the ASAS criteria at baseline had axSpA, and 37% at follow-up; 96% of axSpA patients according to the MDT consensus met the ASAS criteria at baseline and 92% at follow-up. CONCLUSION: Approximately one-third of the included patients had axSpA when evaluated at the MDT conference. The ASAS criteria had low predictive value, but high sensitivity at both baseline and follow-up.

Clinical characteristics of axial spondyloarthritis patients in China: results from ChinaSpA, the Chinese Spondyloarthritis Registry.

OBJECTIVES: The objective of this study is to describe the clinical features of patients with axial spondyloarthritis (axial SpA) in the ChinaSpA registry. METHODS: Patients with clinical diagnosis of ankylosing spondylitis (AS) or axial SpA were enrolled into the registry. Patients with a complete set of pelvis radiograph, pelvis MRI and HLA-B27 (Complete Set group, CS group) were further categorised based on classification criteria into AS, radiographic axial SpA (r-axSpA) and non-radiographic axial SpA (nr-axSpA). Early axial SpA was defined as symptom duration of less than three years. Descriptive statistics were used to describe clinical characteristics of enrolled patients. ANOVA analyses were used to compare patients in different groups. RESULTS: A total of 5270 patients were enrolled in the study, and 3223 patients had complete sets of pelvis radiographs, MRIs and HLA-B27 status. Among them, more than 80% patients met both the ASAS criteria for r-axSpA and the modified New York criteria for AS. Among those with early axial SpA, 92% of patients had sacroiliitis on pelvis radiograph, 3.8% had sacroiliitis only on pelvis MRI, and 3.8% were in the clinical arm without any sacroiliitis on imaging studies. Patients in nr-axSpA clinical arm had less diagnosis delay, lower inflammatory markers and ASDAS, compared topatients in the r-axSpA, nr-axSpA MRI arm. CONCLUSIONS: In the ChinaSpA registry, patients in nr-axSpA clinical arm had the shortest diagnostic delay, lower inflammatory markers and ASDAS, but no difference in extra-articular manifestation, compared to patients in the r-axSpA and nr-axSpA MRI arm.