Sex-specific diagnostic efficacy of MRI in axial spondyloarthritis: challenging the 'One Size Fits All' notion.

OBJECTIVES: Sex-specific differences in the presentation of axial spondyloarthritis (axSpA) may contribute to a diagnostic delay in women. The aim of this study was to investigate the diagnostic performance of MRI findings comparing men and women. METHODS: Patients with back pain from six different prospective cohorts (n=1194) were screened for inclusion in this post hoc analysis. Two blinded readers scored the MRI data sets independently for the presence of ankylosis, erosion, sclerosis, fat metaplasia and bone marrow oedema. Χ2 tests were performed to compare lesion frequencies. Contingency tables were used to calculate markers for diagnostic performance, with clinical diagnosis as the standard of reference. The positive and negative likelihood ratios (LR+/LR-) were used to calculate the diagnostic OR (DOR) to assess the diagnostic performance. RESULTS: After application of exclusion criteria, 526 patients (379 axSpA (136 women and 243 men) and 147 controls with chronic low back pain) were included. No major sex-specific differences in the diagnostic performance were shown for bone marrow oedema (DOR m: 3.0; f: 3.9). Fat metaplasia showed a better diagnostic performance in men (DOR 37.9) than in women (DOR 5.0). Lower specificity was seen in women for erosions (77% vs 87%), sclerosis (44% vs 66%), fat metaplasia (87% vs 96%). CONCLUSION: The diagnostic performance of structural MRI markers is substantially lower in female patients with axSpA; active inflammatory lesions show comparable performance in both sexes, while still overall inferior to structural markers. This leads to a comparably higher risk of false positive findings in women.

Association of biomarkers of inflammation, cartilage and bone turnover with gender, disease activity, radiological damage and sacroiliitis by magnetic resonance imaging in patients with early spondyloarthritis.

To assess the association between biomarkers of inflammation, cartilage and bone turnover with gender, Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Spondylitis Disease Activity Score (ASDAS) and bone marrow oedema in resonance magnetic imaging (MRI) of sacroiliac joints (SIJs) and radiological damage in early spondyloarthritis (SpA). Cross-sectional study of 60 patients (56.7 % females; mean age, 32.4 years) with early SpA. Sociodemographic data, clinical features, serum matrix metalloproteinase 3 (MMP-3), high sensitivity C-reactive protein (hsCRP), C-terminal cross-linking telopeptides of type I collagen (CTX-I) and urinary deoxypyridinoline, ASDAS, BASDAI, BASFI, BASRI and MRI of the SIJs were collected. The mean (SD) disease duration was 12.4 (6.8 months). Twenty-two (68.7 %) of the 32 patients had active sacroiliitis by MRI. MMP-3 and CTX I correlated with swollen joint (r = 0.515, r = 0.386, p = 0.01). hsCRP correlated with ESR (r = 0.303, p = 0.05), with CRP (r = 0.455, p = 0.01) and with total BASRI (r = 0.95, p = 0.05). Biomarkers were unrelated with the rest of variables. Levels of MMP-3 (44.3 ± 52.4 vs 24.7 ± 33.4, p < 0.05) and CTX-I (0.53 ± 0.45 vs 0.24 ± 0.38; p < 0.05) were higher in men. Our study shows that CTX-I and MMP-3 are a marker of peripheral disease activity in early SpA. Male gender had higher levels of CTX-I and MMP-3, which may indicate higher disease activity. Higher hsCRP levels trended towards correlation with more baseline radiographic damage. Therefore, these biomarkers may help identify a subgroup of patients who will need closer monitoring and more intensive treatment.