Increased incidence of critical illness among patients with inflammatory bowel disease: a population-based study

Background & aims: Little is known about how often, and for what reasons, patients with inflammatory bowel diseases (IBD) are admitted to the intensive care unit (ICU). We compared incidences of ICU admission, characteristics of critical illness, and mortality after ICU admission between patients with IBD and the general population.

Methods: We identified all persons with IBD in the province of Manitoba using a validated administrative definition of IBD for the period from 1984 to 2010. Cases were considered incident for IBD if their first health system contact for IBD was in 1989 or later. We identified a population-based control group, matched by age, sex, and geography (based on postal code). Case and control cohorts were linked to the Manitoba ICU database. We compared outcomes between groups using age- and sex-standardized rates, Cox proportional hazards models, and logistic regression models, adjusting for age, sex, comorbidity, and socioeconomic status.

Results: There were 8224 prevalent and 4580 incident cases of IBD. After adjustment, the risk for ICU admission was higher for patients with IBD than controls (hazard ratio [HR], 1.79; 95% confidence interval [CI], 1.58-2.02). The risk of ICU admission was higher for patients with Crohn's disease (HR, 2.31; 95% CI, 1.95-2.75) than ulcerative colitis (HR, 1.37; 95% CI, 1.13-1.65). From 2000 through 2010, age- and sex-standardized annual incidence rates for ICU admission in the prevalent IBD cohort ranged from 0.55% to 1.12%. Compared with controls admitted to ICUs, 1 year after ICU admission, mortality was 32% among patients with IBD.

Conclusions: Patients with IBD have a higher risk for admission to the ICU than the general population, and increased mortality 1 year after admission. These findings underscore the potential severity of IBD.