Long-term prognosis in Crohn's disease: an epidemiological study of patients diagnosed more than 20 years ago in Cardiff

Background To investigate the incidence of death in patients diagnosed with Crohn's disease in Cardiff over 20 years ago. Methods The Cardiff database of patients with Crohn's disease contains data on all patients diagnosed there since 1934. Patients (394) diagnosed before 1 January 1985 were traced and their mortality status on 31 December 2004 was established. Results The overall standardized mortality ratio (SMR) was 1.29 (95% CI 1.12-1.45) and it has not significantly changed since the 1970s. SMR decreases with age, from 16.95 (95% CI 14.99-18.91) for patients aged 10-19 years (although only one death) to 0.92 (95% CI 0.65-1.19) in those over 75 years. Kaplan-Meier analysis of age at death shows that patients diagnosed aged 10-26 years have median age at death of 58 years, those aged 27-52 years of 66 years, those aged 53-58 years of 74 years, and those over 59 years of 79 years. Conclusions It shows a significantly raised SMR, not statistically changed since the 1970s and similar to other chronic conditions. Patients diagnosed younger have worse prognosis than those diagnosed later in life and a reduced life expectancy compared with the general population.