Ulcerative colitis in the Jewish population of southern Israel 1961-1985: epidemiological and clinical study.

The incidence of ulcerative colitis in the Jewish population of Southern Israel has increased in the period 1961-85 and is presently 5.8/10(5)/year. The mean annual incidence was significantly higher in European and American born (10.8/10(5)/year) than in Asian and African or Israeli born Jews. The disease was significantly more prevalent in women, who developed the illness at a younger age and had a milder course. The age adjusted prevalence rate in each population group was greater than the rates detected by earlier studies in other areas of the country (p less than 0.05). The prevalence rate in the total population now approximates the moderate to high prevalence rates of ulcerative colitis found in many other localities. The particularly high rates of ulcerative colitis in the European and American born population in Israel, in Jews residing in Western countries, and in certain non-Jewish populations in Great Britain and Northern Europe may imply the presence of a common aetiological mechanism.