title: Seasonal variations in the clinical of presentation of Crohn's disease and ulcerative colitis.
abstract: Epidemiological evidence that Crohn's disease could be a transmissible condition is limited. The case histories of 211 patients with Crohn's disease and 201 patients with ulcerative colitis have been scrutinized to ascertain whether there is a seasonal variation in the onset of symptomatic disease. Crohn's disease has a peak onset in January and July whereas ulcerative colitis has a possible peak of onset in December. A hypothesis is proposed that these findings provide epidemiological evidence, suggesting that Crohn's disease could be a transmissible condition, and that Crohn's disease and ulcerative colitis may not be aetiologically related.
authors.affiliation: St. George's Hospital Medical School, Hyde Park Corner, London, S.W.1, England.
authors.forename: D R
authors.initials: DR
authors.lastname: Cave
authors.forename: L S
authors.initials: LS
authors.lastname: Freedman
mesh_terms: D000328:Adult; D017668:Age of Onset; D003093:Colitis, Ulcerative / Q000175:diagnosis / Q000453:epidemiology / Q000503:physiopathology; D003424:Crohn Disease / Q000175:diagnosis / Q000453:epidemiology / Q000503:physiopathology; D004781:Environmental Exposure / Q000009:adverse effects / Q000032:analysis / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D008297:Male; D012307:Risk Factors; D012621:Seasons; D063189:Symptom Assessment / Q000379:methods; D006113:United Kingdom / Q000453:epidemiology