Sarcoidosis affects people of all ages and races. However, it's more common among African Americans and Northern Europeans. In the United States, the disease affects African Americans somewhat more often and more severely than Whites.
Studies have shown that sarcoidosis tends to vary amongst ethnic groups. For example, eye problems related to the disease are more common in Japanese people.
Lofgren's syndrome, a type of sarcoidosis, is more common in people of European descent. Lofgren's syndrome may involve fever, enlarged lymph nodes, arthritis (usually in the ankles), and/or erythema nodosum. Erythema nodosum is a rash of red or reddish-purple bumps on your ankles and shins. The rash may be warm and tender to the touch.
Sarcoidosis is somewhat more common in women than in men. The disease usually develops between the ages of 20 and 50. People who have a family history of sarcoidosis also are at higher risk for the disease.
Researchers have looked for a link between sarcoidosis and exposure to workplace and environmental factors. However, no clear link has been found.