Clinical and epidemiological differences between men and women with systemic sclerosis: a study in a Spanish systemic sclerosis cohort and literature review.

Objectives: The low overall prevalence of systemic sclerosis (SSc) and the low proportion of male patients have resulted in a scarcity of studies assessing sex differences in Ssc patients, and contradictory results have often been show among those studies that have been performed.

Methods: A prospective study was conducted with the Spanish RESCLE register to analyse the influence of gender on survival of SSc patients.

Results: In total, 1506 SSc patients (1341 women, 165 men) were recruited from 21 centres. Older age at onset (OR 1.02), shorter time from onset to diagnosis (OR 0.96), smoking (OR 2.57), interstitial lung disease (ILD) (OR 1.58), less predisposition to sicca syndrome and to antinuclear antibody positivity (OR 0.29 and 0.43, respectively), and higher compliance with the ACR 1980 criteria (OR 1.79) were independently associated with the male sex. During follow-up, 30.4% of men versus 14.6% of women died (p<0.001). Survival at 10 years from the onset of symptoms was 75.3% for men and 92.9% for women (p<0.001), and the difference remained after selecting only SSc-related deaths (85.6% vs. 96.1%, p<0.001). The mortality predictive factors were diffuse SSc (OR 2.26), ILD (OR 1.82), digital ulcers (OR 1.38), tendon friction rubs (OR 1.74), male sex (OR 1.53), increased age at onset (OR 1.13) and isolated PH (considering only deaths from diagnosis), both in the overall (OR 3.63) and female cohorts (OR 3.97). The same risk factors were observed in the male cohort, except for isolated PH and ILD.

Conclusions: The present study confirms the existence of epidemiological, clinical, laboratory and prognostic gender differences in systemic sclerosis patients.