title: Time relationships between cessation of smoking and onset of ulcerative colitis.
abstract: From 5 centres 154 patients with ulcerative colitis and a history of smoking completed a questionnaire about the temporal relationship between diagnosis of colitis and cessation of smoking. One hundred and thirty-eight of these were ex-smokers and 107 (69.5%) had stopped smoking before the diagnosis of colitis was made. Fifty-six patients (52%) developed colitis within 3 years of stopping smoking. The findings suggest that smoking exerts protective effect against the development of ulcerative colitis.
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D003093:Colitis, Ulcerative / Q000453:epidemiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012907:Smoking