Long term prognosis in ulcerative colitis--based on results from a regional patient group from the county of Copenhagen.

The prognosis of ulcerative colitis including survival, colectomy rate, activity of disease, and working capacity was estimated from a follow up study of 783 patients with ulcerative colitis comprising all patients from the county of Copenhagen, except for the island of Amager, diagnosed between 1960 and 1978. The period of observation ranged from one to 18 years with a median of 6.7 years for the clinical observations, eight years for survival and 11.6 years for the occurrence of large bowel cancer. The follow up was 100% for both survival and cancer. The survival rate in women did not differ from that in the general population. In men over 40 years of age at diagnosis a slight excess mortality was found, but only in the year of diagnosis (2.1%) and the following year (1.5%). Colonic cancer was seen in only seven out of the 783 patients, corresponding to an annual risk of 0.07% and a cumulative risk after 18 years with ulcerative colitis of 1.4% (95% confidence limits, 0.7-2.8%) independent of the initial extent of disease. The colectomy rate was 9.6% in the year of diagnosis. The cumulative 10- and 18-year colectomy rate was 23% and 31%, respectively. After three years from diagnosis the capacity for work both in those subject to resection and treated conservatively did not differ significantly from that in the background population. At any time about 50% of the patients were without symptoms, in about 30% the disease activity was low and in about 20% moderate or high. Most patients, however, differed in activity from one year to another and almost all patients (97%) experienced at least one relapse during a 10 year time period.