Sex differential impact of comorbidities in spondyloarthritis: data from COMOSPA study.

OBJECTIVES: To describe and compare the prevalence of comorbidities in female and male patients with spondyloarthritis (SpA) and to assess whether comorbidities had a different impact on disease outcomes in male and female patients. METHODS: This is a post hoc analysis of the COMOrbidities in SPondyloArthritis study. Differences in comorbidities regarding sex were assessed using logistic regression models. Comorbidities were evaluated for their impact on disease outcomes (Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Ankylosing Spondylitis Disease Activity Score (ASDAS), Bath Ankylosing Spondylitis Functional Index, European health-related quality of life questionnaire) with linear models, which included sex and comorbidity as explanatory variables and their interaction. Age and treatment with biological synthetic disease-modifying antirheumatic drugs were included as confounders. RESULTS: We included 3982 patients with SpA (65% male, mean age 43.6 years). Male and female patients with SpA exhibited similar comorbidity profiles, except for a low prevalence of fibromyalgia in males and a higher prevalence of certain cardiovascular risk factors in males (hypertension, dyslipidaemia, renal impairment and ischaemic heart disease). Comorbidities, especially fibromyalgia, correlated with higher disease activity, decreased physical function and reduced health-related quality of life in both sexes. Some comorbidities exhibited sex-specific associations with disease outcomes. Peptic ulcers and high waist circumference had a greater impact on disease activity in females (with a higher impact in BASDAI than in ASDAS). In contrast, osteoporosis had a more pronounced effect on physical function in male patients. CONCLUSIONS: Comorbidities exert distinct influences on disease activity, physical function and health-related quality of life in male and female patients with SpA. Understanding these sex-specific effects is crucial for improving SpA management, emphasising the importance of assessing disease activity using ASDAS when comorbidities are present to mitigate sex-related disparities in disease assessment.

Association between HLA-B27 and peripheral spondyloarthritis phenotype: results from the ASAS perSpA study.

OBJECTIVE: To analyse the influence of HLA-B27 in the phenotypical expression of peripheral spondyloarthritis (pSpA). METHOD: This is an observational cross-sectional study using data from the Assessment of SpondyloArthritis international Society perSpA registry, including all patients with an available HLA-B27 test result and with a diagnosis of pSpA or psoriatic arthritis (PsA) as per rheumatologist's judgement. Demographic and clinical data, presence of extra musculoskeletal manifestations (EMM) and fibromyalgia were the variables included in a simple and multiple logistic regression model to assess their association to HLA-B27 positivity. RESULTS: From the 4465 patients included in the registry, 790 were classified as having either pSpA or PsA and had the HLA-B27 typing available. HLA-B27-positive patients presented a male predominance, had an earlier disease onset and a shorter diagnostic delay compared with the negatives. HLA-B27-positive patients presented a higher frequency of axial involvement, radiographic sacroiliitis, enthesitis and uveitis. Also, root joint involvement, poliarticular joint patern and tarsitis were significantly higher within HLA-B27-positive patients. Furthermore, we did not observe any association between the presence of HLA-B27 and peripheral joint damage, dactylitis, other EMM (psoriasis, inflammatory bowel disease) or fibromyalgia.The multivariable analysis confirmed the independent association of HLA-B27 positivity with male sex, an earlier onset of the disease, the presence of axial involvement, tarsitis and uveitis. SUMMARY: In summary, the presence of HLA-B27 in pSpA patients was associated with earlier disease onset and higher axial involvement, tarsitis and uveitis, but not with other EMM, fibromyalgia or peripheral structural damage.