Total and cancer mortality in a cohort of ulcerative colitis and Crohn's disease patients: The Florence inflammatory bowel disease study, 1978–2010

Background There is no consensus on the leading causes of death among inflammatory bowel diseases (IBD) patients. Aim We present the results of an extended follow-up of the population-based Florence IBD cohort, including 689 ulcerative colitis and 231 Crohn's disease patients. Methods The causes of death of cohort members were determined through linkage with the local mortality registry. We calculated standardized mortality ratios (SMR) and 95% confidence intervals (95%CI) by applying gender-, age- and calendar time–death rates to person-years at risk. Results Ulcerative colitis patients had overall mortality comparable to the general population (SMR 0.99, 95%CI 0.85–1.14), though being at increased risk of dying from Hodgkin's disease (SMR 11.74, 95%CI 2.94–46.94), rectal cancer (SMR 3.69, 95%CI 1.66–8.22) and Alzheimer's disease (2.40, 95%CI 1.00–5.76). Crohn's disease patients had an increased overall mortality (SMR 1.79, 95%CI 1.39–2.27) and were at higher risk of dying from cancer (SMR 2.57, 95%CI 1.28–5.13) and non-cancer diseases of the respiratory system (SMR 2.51, 95%CI 1.05–6.04), brain cancer (SMR 6.26, 95%CI 1.57–25.02) and non-cancer diseases of the genitourinary system (SMR 4.38, 95%CI 1.10–17.52). Conclusions IBD patients should be offered counselling on risk reduction strategies, as much of their mortality excess is potentially avoidable.