Prognosis in Crohn's disease--based on results from a regional patient group from the county of Copenhagen.

All patients in the county of Copenhagen (approximately 500 000 inhabitants) with Crohn's disease, n = 185 were followed regularly between 1960 and 1978. The survival, the course of disease, the frequency of surgery, and the working capacity were estimated for the first 10 years of disease on the basis of the follow up results. The observation time ranged from 1-18 years with a median of 5.5 years for clinical observations, 5.8 years for survival, and 9.5 years for the occurrence of gastrointestinal cancer. The follow up was 100% concerning survival and cancer. The survival did not differ from that of the age- and sex-matched background population. Cancer was seen in only one of 185 patients corresponding to an annual risk of 0.06% and a cumulated risk after 10 years of 0.56, 95% confidence limits: 0.1-3.1%. The cancer was localised in the ileum. For all years, about 45% of the patients were without clinical symptoms of their disease, in 30% the clinical disease activity was low, and in 25% moderate to high. Among the patients with active disease, the course within the individual year was continuous in about one third and intermittent in about two thirds. After 10 years, 99% of the patients had experienced at least one relapse. The operation rate was 33% in the year of diagnosis, 13% in the following year, and then about 3% per year independent of whether or not the patient had been treated surgically in the past. After 10 years, 45% of the patients had not been treated surgically, 42% had had only one operation, and 13% had had two or more operations for their Crohn's disease. The working capacity was normal in about 75% of the patients for all years except the year of diagnosis. About 15-20% of the patients who had had the disease for more than five years were disabled as compared with about 4.4% of the background population. These results indicate that some of the patients with Crohn's disease run a more serious course with continuing symptoms despite of medical treatment and frequent surgical interventions. Most patients, however, remained capable for work and were able to lead a normal life.