Survival and Cause-Specific Mortality in Ulcerative Colitis: Follow-up of a Population-Based Cohort in Copenhagen County

Abstract

Background & Aims: A population-based cohort from Copenhagen County comprising 1160 patients diagnosed with ulcerative colitis between 1962 and 1987 was followed-up until 1997 to describe survival and cause-specific mortality. Methods: Observed vs. expected deaths were presented as standardized mortality ratio (SMR) with exact 95% confidence intervals (CI) calculated by using individually registered person-years at risk and Danish 1995 mortality rates. Cumulative survival curves were calculated. Results: A total of 261 deaths occurred, not significantly different from the expected number of 249 (SMR, 1.05; 95% CI, 0.92-1.19). The median age at death among men was 70 years (range, 6-96 years) and among women 74 years (range, 25-96 years). Twenty-five deaths (9.6%) were caused by complications to ulcerative colitis, mostly infectious and cardiovascular postoperative complications. Patients older than 50 years of age at diagnosis and with extensive colitis showed an increased mortality within the first 2 years because of ulcerative colitis-associated causes. The mortality from colorectal cancer was not increased and that of cancer in general was significantly lower than expected: 50 vs. 71 (SMR, 0.70; 95% CI, 0.52-0.93). A significantly increased mortality from pulmonary embolism and pneumonia was found. Among women only, death from genitourinary tract diseases and suicide was significantly increased. Conclusions: Despite an overall normal life expectancy for patients with ulcerative colitis, patients >50 years of age and with extensive colitis at diagnosis had increased mortality within the first 2 years after diagnosis, owing to colitis-associated postoperative complications and comorbidity.