Effect of gender and age on bDMARD efficacy for axial spondyloarthritis patients: a meta-analysis of randomized controlled trials.

Objective: To study the therapeutic variations of biologic and targeted synthetic DMARDs (b/tsDMARDs) between genders and across age stages in axial SpA (axSpA) patients through meta-analysis.

Methods: Randomized controlled trials published by PubMed, Scopus and Embase before 10 August 2023, testing the efficacy of b/tsDMARDs in axSpA, were searched and systematically reviewed. The Assessment of Spondyloarthritis International Society ≥40% improvement (ASAS40) was used as the primary outcome of treatment response.

Results: Only one study meet the inclusion criteria related to tsDMARDs, which was excluded from further analysis. Nine studies of bDMARDs, with 4127 patients, were included for the final analysis. When compared with placebo, both males [odds ratio (OR) 3.14 (95% CI 2.66, 3.70)] and females [OR 2.32 (95% CI 1.82, 2.82)] and younger [OR 4.00 (95% CI 2.50, 6.40)] and older [OR 2.21 (95% CI 1.15, 4.22)] patients presented significantly better responses to bDMARDs. Also, the efficacies were more evident in males [OR 1.89 (95% CI 1.56, 2.30)] and younger [OR 2.07 (95% CI 1.42, 3.02)] patients. Subgroup analysis revealed that the gender difference in efficacy was more obvious in non-radiographic axSpA (nr-axSpA) patients (Pheterogeneity = 0.03, I2 = 78.1%). Moreover, males with radiographic axSpA (r-axSpA) and nr-axSpA shared similar responses to bDMARDs (Pheterogeneity = 0.87, I2 = 0%), while females with r-axSpA showed greater response than those with nr-axSpA (Pheterogeneity = 0.005, I2 = 87.4%).

Conclusions: The bDMARDs were efficacious in all axSpA patients regardless of gender or age. However, the treatment responses were more evident in male and younger patients. Also, females with r-axSpA had greater responses than those with nr-axSpA, whereas no relevant difference was observed in males, indicating that the gender difference on efficacy was greater in nr-axSpA patients.