Sex
Age
Race
Frequency - United States
Frequency - International
Systemic sclerosis usually appears in women aged 30-40 years, and it occurs in slightly older men. In approximately 85% of cases, systemic sclerosis develops in individuals aged 20-60 years. Cases also are observed in children and in the elderly population.
Systemic sclerosis is estimated to occur in 2.3-10 people per 1 million. Systemic sclerosis is rare in the resident population of Japan and China.
Overall, a substantial female predominance exists, with a female-to-male ratio of 3-6:1. However, dSSc occurs equally in males and females. The limited form of systemic sclerosis (lSSc) has a strong female predominance, with a female-to-male ratio of 10:1. Another analysis showed that men tend to have diffuse disease and women to have calcinosis.
No apparent racial predominance exists. However, systemic sclerosis is rare in the resident population of Japan and China. Diffuse systemic sclerosis (dSSc) occurs more often in black women than in white women.
Systemic sclerosis is a rare disease. Systemic sclerosis is diagnosed in approximately 67 male patients and 265 female patients per 100,000 people each year.
