Rheumatoid arthritis and gout in Hiroshima and Nagasaki, Japan. A prevalence and incidence study.

SINCE 1958, the Atomic Bomb Casualty Commission (ABCC) has been conducting a long-term follow-up investigation (Adult Health Study) [ 1] of large defined population samples in Hiroshima and Nagasaki, Japan. In the course of this program the prevalence of definite rheumatoid arthritis was measured and its incidence estimated, according to observations made upon 16,269 subjects from 1958 to 1964 [2]. The original observations were made during routine medical examinations, not specifically designed to detect rheumatoid arthritis, and with the inherent disadvantages of a retrospective approach. A prospective rheumatic disease study was therefore conducted at ABCC from 1965 to 1967 for the specific detection of rheumatic diseases and to determine age-sex specific prevalence and the incidence of rheumatoid arthritis. It was also intended (1) to define the natural history of rheumatoid arthritis as related to physical and environmental factors; (2) to detect any relationship between A-bomb radiation exposure and the disease; (3) to define the