Sex-related Differences in Systemic Sclerosis: A Multicenter Cross-sectional Study From the National Registry of the Italian Society for Rheumatology

Objective: There is still a great deal to learn about the influence of sex in systemic sclerosis (SSc). In this respect, national registries provide large and homogeneous patient cohorts for analytical studies. We therefore investigated a wide-ranging and well-characterized SSc series with the aim of identifying sex differences in disease expression, with a special focus on demographic, clinical, and serological characteristics. Methods: A multicenter SSc cohort of 2281 patients, including 247 men, was recruited in the Italian Systemic sclerosis PRogression INvestiGation (SPRING) registry. Demographic data, disease manifestations, serological profile, and internal organ involvement were compared. Results: The overall female/male ratio was 8.2:1. Female/male ratios for limited cutaneous SSc, diffuse cutaneous SSc, and SSc sine scleroderma subsets were 8.7:1, 4.9:1, and 10.7:1, respectively. A shorter time from onset of Raynaud phenomenon to SSc diagnosis, an increased prevalence of the diffuse cutaneous subset, renal crisis, and digital ulcers were found in males, whereas a significantly higher percentage of sicca syndrome, serum antinuclear antibodies, antiextractable nuclear antigens, anti-La/SSB, and anticentromere protein B was detected in the female group. Males exhibited lower left ventricular ejection fraction, as well as higher prevalence of conduction blocks, arrhythmias, ground glass, and honeycombing. Moreover, forced vital capacity and total lung capacity were medially lower in men than in women. Finally, males were more frequently treated with immunosuppressive drugs. Conclusion: Our study further supports the presence of several sex-related differences in patients with SSc. These differences were pronounced in the severity of cutaneous, peripheral vascular, and cardiopulmonary involvement for male patients, whereas an increased prevalence of sicca syndrome and a specific autoantibody profile characterized the female sex.