[A case-control study of ulcerative colitis].

In order to evaluate the epidemiological characteristics of ulcerative colitis, we conducted a matched case-control study of ulcerative colitis. Fifty patients with ulcerative colitis diagnosed at three hospitals in Kyoto, Osaka and Hyogo Prefectures in Japan during 1984 and 1987 were interviewed about their habitual and pre-illness diets, personal habits, past histories and family histories. The results were compared to those for fifty healthy controls who were matched for sex and age (+/- 2 years) and participated in health-screening examinations in Kyoto or Osaka during the same period. Frequent intake of rice (4 or more bowls a day), bread (3 or more times a week), and green tea (7 or more cups a day) significantly increased the relative risk of ulcerative colitis. However, a past history of appendectomy was negatively correlated with the disease. There were no relationships between ulcerative colitis and consumption of animal foods and tobacco.