Epidemiology, prevalence, economic burden, vulnerable populations Sarcoidosis affects people 
of all ages throughout the world, with the highest incidence in those between the ages of 20 and 40 (1). There are significant racial and gender differences in disease severity, incidence, and prevalence. Worldwide, women are more often affected than men. The highest annual incidence has been observed in northern European countries, at 5 to 40 cases per 100,000 people per year (2).

With 36 cases per 100,000 people per year, African Americans are about 3 times more likely than Caucasian Americans (11 cases per 100,000) to have sarcoidosis. African American women are the most commonly affected group, with nearly a 3 percent lifetime risk for developing sarcoidosis (1). Sarcoidosis in African Americans is also more likely to be chronic, involve several organs, and lead to death (3).

No data on the economic burden due to sarcoidosis is available. Fatigue, joint pain, and shortness of breath can lead to lost work days and necessitate transfer to a less physically demanding job. Sarcoidosis accounts for less than 1 percent of hospital admissions in the United States (4). Exposure to inorganic particles, insecticides, and moldy environments has been reported to be associated with sarcoidosis. Occupational studies have shown positive associations with metalworking, firefighting, service in the U.S. Navy, and handling of building supplies. Investigators have reported an increased incidence of sarcoidosis among New York City Fire Department rescue workers involved in the World Trade Center attacks of September 11, 2001. Socioeconomic status does not affect the risk of sarcoidosis, but low income and other financial barriers to care are associated with more severe sarcoidosis (5).

Susceptibility to sarcoidosis depends on an interaction between inherited genes and environmental exposures. Relatives of sarcoidosis patients are at higher risk of developing sarcoidosis compared to the general population. However, while family members are at higher risk, less than 1 percent of first- and second-degree relatives of sarcoidosis patients develop sarcoidosis (6). Sarcoidosis is not transmissible, and cigarette smokers are not at increased risk of developing sarcoidosis.