Rehospitalization rates, costs, and risk factors for inflammatory bowel disease: a 16-year nationwide study

Aims: We aimed to describe the burden of rehospitalization in patients with inflammatory bowel disease (IBD), by evaluating rehospitalization rates, charges, and risk factors over 16 years. Methods: We performed a retrospective analysis of all hospital discharges with a primary diagnosis of IBD in public hospitals between 2000 and 2015 in mainland Portugal from the Central Administration of the Health System (ACSS)'s national registry. We collected data on patient, clinical, and healthcare charges. We used survival analysis to estimate the rate and risk factors of IBD-related rehospitalization. Results: We found that 33% (n = 15,931) of the IBD-related hospitalizations corresponded to rehospitalizations, which increased by 12% over 16 years. However, IBD rehospitalization rate per 100,000 IBD patients decreased 2.5-fold between 2003 and 2015. Mean IBD-related rehospitalization charges were euro14,589/hospitalization-year in 2000 and euro17,548 /hospitalization-year in 2015, with total rehospitalization charges reaching euro3.1 million/year by 2015. Overall, the 30-day rate of rehospitalization was 24% for Crohn's disease (CD) and 22.4% for ulcerative colitis (UC). Novel risk factors for rehospitalization include penetrating disease in CD patients {hazard ratio (HR) 1.34 [95% confidence interval (CI) 1.20-1.51], p < 0.001} and colostomy in UC patients [HR 2.84 (95% CI 1.06-7.58)]. Conclusion: IBD-related rehospitalization should be closely monitored, and efforts to reduce its risk factors should be made to improve the quality of care and, consequently, to reduce the burden of IBD.