High prevalence of Crohn disease and ulcerative colitis among older people in Sydney

To determine the age-standardised prevalence of inflammatory bowel disease (IBD) in a metropolitan area of Sydney, with a focus on its prevalence among older people.

Population-based epidemiological study of people with IBD in the City of Canada Bay, a local government area in the inner west of Sydney, during 1 March 2016 - 10 November 2016.

Patients diagnosed with confirmed IBD according to the Copenhagen or revised Porto criteria.

Crude prevalence of IBD, including Crohn disease and ulcerative colitis; age-standardised prevalence of IBD, based on the World Health Organization standard population; prevalence rates among people aged 65 years or more.

The median age of 364 people with IBD was 47 years (IQR, 34-62 years); 185 were women (50.8%). The crude IBD prevalence rate was 414 cases (95% CI, 371-456 cases) per 100 000 population; the age-standardised rate was 348 cases (95% CI, 312-385 cases) per 100 000 population. The age-standardised rate for Crohn disease was 166 cases (95% CI, 141-192 cases) per 100 000 population; for ulcerative colitis, 148 cases (95% CI, 124-171 cases) per 100 000 population. The IBD prevalence rate in people aged 65 years or more was 612 cases (95% CI, 564-660 cases) per 100 000, and for those aged 85 years or more, 891 cases (95% CI, 833-949 cases) per 100 000; for people under 65, the rate was 380 cases (95% CI, 342-418 cases) per 100 000.

We found that the prevalence of confirmed IBD in a metropolitan sample was highest among older people. Challenges for managing older patients with IBD include higher rates of comorbid conditions, polypharmacy, and cognitive decline, and the immunosuppressive nature of standard therapies for IBD.