Changes in medical management and colectomy rates: a population-based cohort study on the epidemiology and natural history of ulcerative colitis in Örebro, Sweden, 1963-2010.

BACKGROUND: Whether the epidemiology of ulcerative colitis (UC) has changed during recent decades is partly unknown.

AIM: To depict temporal trends in the epidemiology and medical treatment of UC as well as the long-term risk of progression in disease extent and colectomy, during 1963-2010.

METHODS: Patients were identified by evaluation of all medical records in the archive of the Colitis Clinic, Örebro University Hospital. Comparisons were made between three time periods, 1963-1975, 1976-1990 and 1991-2005.

RESULTS: The annual age-standardised incidence increased from 3.5 to 18.5 per 100 000 during the study period (P < .01). Correspondingly, the prevalence increased from 44 to 474 per 100 000 between 1965 and 2010. A higher proportion of males than females had extensive colitis at diagnosis (odds ratio: 1.55; 95% CI 1.17-2.05; P < .01). The risk for progression in disease extent was 34.5% and 18.5% at 10 years, for patients with proctitis and left-sided colitis, respectively (P < .01). The use of 5-aminosalicylates, within 10 years, rise from 79% to 92% between 1963-1975 and 1976-1990 (P < .01). Thiopurine use increased from 7% in 1976-1990 to 34% during 1991-2005 (P < .01). The colectomy rate at 10 years was 13.5% (95% CI 11.1%-15.8%), and the risk was lower among patients diagnosed in 1991-2005 compared to 1963-1975 (adjusted hazard ratio: 0.61; 95% CI 0.39-0.94; P = .02).

CONCLUSION: The incidence and prevalence of UC increased over time, and the observed prevalence in 2010 is among the highest reported. In parallel, a decrease in colectomy rates was observed during the most recent decades, potentially reflecting improved medical treatment.