Ulcerative colitis and clinical course: results of a 5-year population-based follow-up study (the IBSEN study).

BACKGROUND: The majority of studies concerning the clinical course and prognosis in ulcerative colitis (UC) are old, retrospective in design, or hospital based. We aimed to identify clinical course and prognosis in a prospective, population-based follow-up study
MATERIALS AND METHODS: Patients diagnosed with inflammatory bowel disease (IBD) or possible IBD in southeastern Norway during the period 1990-1994 were followed prospectively for 5 years. The evaluation at 5 years included an interview, clinical examination, laboratory tests, and colonoscopy.
RESULTS: Of 843 patients diagnosed with IBD, 454 patients who had definite UC and for whom there were sufficient data for analysis were alive 5 years after inclusion in the study. The frequency of colectomy in this population was 7.5%. Forty-one percent of the patients were not taking any kind of medication for IBD at 5 years. Of the patients initially diagnosed with proctitis, 28% had progressed during the observation period, 10% to extensive colitis. The majority of the patients (57%) had no intestinal symptoms at 5 years, and only a minority (7%) had symptoms that interfered with everyday activities. Among the patients who underwent colonoscopy at the 5-year visit, symptoms were frequently reported in patients without macroscopic inflammation (44%). A relapse-free course was observed in 22% of the patients. A decrease in symptoms during the follow-up period was the most frequent course taken by the disease and was observed in 59% of the cases. The extent of disease was unrelated to symptoms at 5 years and also to relapse rate and course of disease during the 5-year period.
CONCLUSIONS: The disease course and prognosis of UC appears better than previously described in the literature. The frequency of surgery was low, and only a minority of the patients had symptoms that interfered with their everyday activities 5 years after diagnosis.