Systemic sclerosis: A comprehensive systematic review of global epidemiology, sex and ethnic disparities, disease burden, and organ-specific involvement.

The global epidemiology, regional variation, sex- and ethnicity-based disparities, disease burden, and organ-specific involvement in systemic sclerosis were reviewed. A qualitative systematic search of PubMed/MEDLINE, EMBASE, SciELO, and the Cochrane Library was conducted following PRISMA 2020 guidelines. Forty-seven studies reporting incidence, prevalence, organ involvement, mortality, or quality of life were included. Global prevalence ranged from 0.9 to 37.9 per 100,000 and incidence from 0.05 to 4.1 per 100,000 person-years, with marked geographic heterogeneity across the globe. Women were predominantly affected (4-6:1), whereas men showed more severe disease and higher mortality. African-descent, Indigenous American, and some South Asian populations had higher frequencies of diffuse cutaneous systemic sclerosis, interstitial lung disease, and reduced survival. Pulmonary involvement accounted for most disease burden, with interstitial lung disease in 35-55% and pulmonary arterial hypertension in 6-12%. These findings highlight substantial epidemiologic heterogeneity and the need for early detection and standardized care in expert centers.