RACIAL-DIFFERENCES IN SARCOIDOSIS INCIDENCE - A 5-YEAR STUDY IN A HEALTH MAINTENANCE ORGANIZATION

Reports of racial differences in the incidence of sarcoidosis, a granu lomatous disorder of unknown etiology, are primarily based on studies of military and veteran populations. To determine racial differences i n sarcoidosis incidence in a metropolitan population, the authors cond ucted a study of newly diagnosed cases that occurred between 1990 and 1994 among members of the Health Alliance Plan hearth maintenance orga nization in Detroit, Michigan. The study population was racially heter ogeneous, was limited to individuals aged 20-69 years, and comprised a bout 5% of the Detroit metropolitan area population in that age group. Annual age-adjusted incidence, in number of new cases per 100,000, wa s highest in African-American females (39.1 cases). The next highest i ncidence was found in African-American males (29.8 cases), followed by Caucasian females (12.1) and Caucasian mates (9.6). African-American females aged 30-39 years were at the greatest risk, with an annual inc idence of 107/100,000. Overall, African Americans had about a threefol d higher age-adjusted annual incidence (35.5/100,000) compared with Ca ucasians (10.9/100,000). Additional adjustment for sex, area of reside nce, and year of study resulted in 3.8-fold greater risk for African A mericans compared with Caucasians. This study further confirmed the hi gher incidence of sarcoidosis in African Americans compared with Cauca sians, but the racial difference was lower than previously reported. T he results should be more generalizable than previous studies done wit h select populations and should serve as a useful frame of reference f or future epidemiologic research of sarcoidosis.