Introduction: Patients with Crohn's disease (CD) or ulcerative colitis (UC) often experience debilitating gastrointestinal complications and extraintestinal manifestations (EIMs). The systemic nature of CD/UC imposes high morbidity on patients during their lifetime. This study aims to quantify the lifetime risk of experiencing intestinal complications and EIMs after CD/UC diagnosis across age groups.
Methods: Patients' lifetime risk of experiencing a complication from age at CD/UC diagnosis to end of life were estimated using duration models. Incident patients with CD/UC from Truven MarketScan databases (from January 2008 to September 2015) were analyzed. A total of 7 intestinal complications and 13 groups of EIMs (based on affected organ/body site) associated with CD/UC were assessed. In order to be classified as a complication case, patients required at least 2 medical claims (ICD-9-CM codes) for a complication in the specific category, and no history of the complication in the year prior to diagnosis (index date). Continuous enrollment for at least 12 months prior to and following index was required for all individuals. Results were compared to 1:1 propensity score matched controls based on age, gender, health plan, and pre-index Charlson comorbidity index. The difference between risks in CD/UC patients and their matched controls were used to estimate additional risk associated with CD/UC.
Results: A total of 34,692 incident CD and 48,196 incident UC patients with matched controls were included. CD/UC patients had an increased risk for all complications when compared to controls (Figure 1). Among intestinal complications, CD patients had the highest cumulative risk of experiencing fistulas/abscesses of (19.7%) and strictures (21.6%), while UC patients were at highest risk of bleeding (21.9%) and strictures (9.1%). Among EIMs, the average lifetime risks ≥10% for CD patients included: (24.7%), physical development and mental health (18.9%), eye (12.1%), skin (11.7%), kidney (11.0%), and joint conditions (10.2%). For UC patients, these included blood (13.5%) and eye complications (12.1%).
Conclusion: CD and UC patients of all ages have a higher lifetime risk of experiencing intestinal complications and EIMs than control patients without CD/UC. When assessing the burden of disease that is imposed upon patients with IBD, it is important to include the burden of the extraintestinal manifestations of IBD as well.