Inflammatory Bowel Disease Cause-specific Mortality: A Primer for Clinicians

BACKGROUND Inflammatory bowel disease (IBD), including Crohn's disease (CD) and ulcerative colitis (UC) is perceived to harbor significant morbidity but limited excess mortality, thought to be driven by colon cancer, compared with the general population. Recent studies suggest mortality rates seem higher than previously understood, and there are emerging threats to mortality. Clinicians must be up to date and able to clearly convey the causes of mortality to arm individual patients with information to meaningfully participate in decisions regarding IBD treatment and maintenance of health. METHODS A MEDLINE search was conducted to capture all relevant articles. Keyword search included: "inflammatory bowel disease," "Crohn's disease," "ulcerative colitis," and "mortality." RESULTS CD and UC have slightly different causes of mortality; however, malignancy and colorectal cancer-associated mortality remains controversial in IBD. CD mortality seems to be driven by gastrointestinal disease, infection, and respiratory diseases. UC mortality was primarily attributable to gastrointestinal disease and infection. Clostridium difficile infection is an emerging cause of mortality in IBD. UC and CD patients have a marked increase in risk of thromboembolic disease. With advances in medical and surgical interventions, the exploration of treatment-associated mortality must continue to be evaluated. CONCLUSIONS Clinicians should be aware that conventional causes of death such as malignancy do not seem to be as significant a burden as originally perceived. However, emerging threats such as infection including C. difficile are noteworthy. Although CD and UC share similar causes of death, there seems to be some differences in cause-specific mortality.