Impact of Comorbid Psychiatric Disorders on Healthcare Utilization in Patients with Inflammatory Bowel Disease: A Nationally Representative Cohort Study.

ABSTRACT

BACKGROUND AND AIMS: Patients with inflammatory bowel disease (IBD) frequently experience comorbid psychiatric disorders, which negatively impact quality of life. We characterized the longitudinal burden of hospitalization-related healthcare utilization in adults with IBD with and without comorbid anxiety, depression, or bipolar disorder. METHODS: In the 2017 Nationwide Readmissions Database (NRD), we identified 40,177 patients with IBD who were hospitalized between January 1, 2017 and June 30, 2017 and who were followed until December 31, 2017. In this cohort, we compared the annual burden (i.e., total days spent in hospital), costs, risk of readmission, inpatient mortality, and IBD-related surgery in patients with and without comorbid psychiatric disorders (anxiety, depression, or bipolar disorder). RESULTS: Of the 40,177 adults who were hospitalized for IBD, 25.7% had comorbid psychiatric disorders. Over a 10 month-long period of follow-up, patients with comorbid psychiatric disorders spent more days in the hospital (median, 7 days vs. 5 days, p < 0.01), experienced higher 30-day (31.3 vs. 25.4%; p < 0.01) and 90-day (42.6 vs. 35.3%, p < 0.01) readmission rates, and had higher hospitalization-related costs (median, $41,418 vs. $39,242, p < 0.01). However, they were less likely to undergo IBD-related procedures or surgeries. There were no differences in risk of mortality. On Cox proportional hazard analysis, the presence of comorbid psychiatric disorders was associated with a 16% higher risk of readmission (HR, 1.16; 95% CI, 1.13-1.20) and a 13% higher risk of severe IBD-related hospitalization (HR, 1.13; 95% CI, 1.08-1.16). CONCLUSIONS: In adults with IBD, comorbid psychiatric disorders were independently associated with a higher burden and cost of hospitalization, without an increase in the risk of IBD-related surgery or procedures. Population-based interventions aimed at treating psychiatric comorbidities may decrease the risk of unplanned healthcare utilization.