Increased incidence of inflammatory bowel disease in Québec residents with airway diseases.

The objective of the study was to assess whether the incidences of Crohn's disease and ulcerative colitis are increased in patients with asthma and chronic obstructive pulmonary disease (COPD) compared to the general population. A population-based retrospective cohort study was conducted using the administrative health databases of Québec, Canada. Incidences of Crohn's disease and ulcerative colitis among patients with asthma and COPD were assessed for the 2001-2006 period. In total, 136 178 subjects with asthma and 143 904 subjects with COPD were identified. The average incidence of Crohn's disease and ulcerative colitis was 23.1 and 8.8 per 100 000 person-years among asthmatic patients; in the COPD cohort there were 26.2 Crohn's disease cases and 17 ulcerative colitis cases per 100 000 person-years. The incidence of Crohn's disease in asthma and COPD patients was 27% and 55% higher than in the general population of Québec; the incidence of ulcerative colitis was 30% higher among COPD patients compared to the general population. Incidence of inflammatory bowel disease was significantly increased in asthma and COPD patients compared to the general population of Québec. Incidence rates were particularly high in patients with COPD. Awareness of an association between airway diseases and inflammatory bowel disease in older age groups may play an important role in earlier detection of bowel disease and in the therapeutic management of such patients.