The Impact of Sex on the Pattern and Clinical Response of Early Psoriatic Arthritis: Real-life Data from the Italian Prospective SIRENA Study

Introduction: Limited data are available on sex differences in the disease characteristics, burden and treatment outcomes of early psoriatic arthritis (PsA). The "Spondyloarthritis Italian Registry: Evidence from a National Pathway" (SIRENA) study is a prospective, observational, Italian study conducted in 23 Rheumatology sites on patients with recent diagnosis of spondyloarthritis and naïve to any disease-modifying antirheumatic drugs (DMARDs). Methods: The study included 203 patients with early PsA, observed per clinical practice, who were studied regarding the influence of sex on the disease presentation and the likelihood of achieving minimal disease activity (MDA). Clinical and patient-reported outcome (PRO) measures were collected at both study entry and each follow-up visit until 24 months. Treatment was assigned by the treating rheumatologist based on standard clinical practice. Results: At baseline, 87% of patients with PsA received systemic treatment, mainly with conventional (49%) or biological (25%) DMARDs. Twenty-three of 158 (15%) patients were already in MDA status at study entry: this percentage increased to 55% (n = 83/150) at 6 months and 75% (n = 73/97) at 24 months. MDA was more frequent in males at baseline (20.0% vs. 8.2% in females, p = 0.036) and throughout the study. Significant improvements in clinical measures and PROs were reported in both sexes at all follow-up visits, but PRO scores were significantly worse in females at baseline and at most endpoints. Increasing age, male sex, new PsA diagnosis, mono-/oligoarticular involvement, low (≤ 14) Disease Activity index for PSoriatic Arthritis (DAPSA) and low Health Assessment Questionnaire Disability Index (HAQ-DI) values showed potential associations with MDA achievement at 6 months in univariate analysis, but this was not significant in the multivariate model. Conclusion: In patients with PsA naïve to DMARDs, sex considerably influences the clinical characteristics and outcomes. Trial registration number: NCT03131661.