Effect of smoking on the long-term course of ulcerative colitis.

Objective. - To evaluate the effects of smoking on the long term clinical c ourse in patients with ulcerative colitis. Methods. - The medical charts of 556 patients with ulcerative colitis were reviewed retrospectively. Patien ts were classified as smokers (n = 85) or nonsmokers (n = 471) according to their smoking status during the course of the disease. Extent of colonic l esions, complications, medical requirements, and actuarial rate of colectom y were compared in smokers and nonsmokers. Results. - Mean follow-up (+/-SD) was longer in smokers than in nonsmokers (116 +/- 107 mo. vs 87 +/- 94 mo.). Less smokers than nonsmokers required o ral steroids (52 vs 63 %, P = 0.05). No difference between the groups was o bserved regarding the use of salicylates, the need for intravenous steroids , for immunosuppressive drugs, for colectomy, and the occurrence of complic ations. The actuarial rate of colectomy was less in smokers than in nonsmok ers (32 +/- 12 % and 42 +/- 6% at 10 years respectively P = 0.04). Initial and cumulative extent of the disease process did not differ between the gro ups. However, in the subgroup of patients with limited disease at onset, de velopment of pancolitis was less frequent in smokers than in nonsmokers (14 and 26 %, respectively, P = 0.04). Conclusion. - The lesser need for oral steroids and the lower actuarial rat e of colectomy ill smokers suggest that ulcerative colitis in smokers is ch aracterized by a less severe clinical presentation and a better long term p rognosis than in nonsmokers.