The incidence of Crohn's disease in Cardiff over the last 75 years: An update for 1996-2005

Background The incidence of Crohn's disease rose rapidly in industralized countries over the past 50 years, but it is unclear whether the incidence is still rising or has reached a plateau. Aims To update the long-term incidence study of Crohn's disease in Cardiff for 1996-2005, to investigate whether incidence is still rising and to study changes in disease characteristics over time. Method Crohn's cases identified by retrospective analysis of hospital records as in previous studies in Cardiff. Results Two hundred and twelve cases were identified. Corrected incidence for this decade was 66 x 106 per year (95% confidence interval: 58-76), showing a continuing rise compared to previous decades. The proportion with colonic disease at presentation continues to rise (43%) with a corresponding fall in those with terminal ileal disease. There remains a strong female preponderance (F:M 1.6:1) as in previous studies. The incidence in children under age 16 continues to rise, and the median age at diagnosis has fallen slightly. Conclusion Crohn's disease incidence continues to rise slowly in Cardiff with a continuing increase in those presenting with colonic disease, which is now the commonest disease pattern.