Background and

Aims: Inflammatory bowel diseases (IBD) lead to high morbidity and unplanned healthcare utilization. We conducted a systematic review with meta-analysis to estimate the cumulative incidence of IBD-related (and all-cause) hospitalization in patients with ulcerative colitis (UC) and Crohn's disease (CD).

Methods: Through a systematic review to September 3, 2019, we identified population-based inception cohort studies in patients with IBD that reported patient-level cumulative incidence of hospitalization at 1, 3 and 5 years after diagnosis. Hospitalization risk was pooled using random effects meta-analysis, and risk factors analyzed through mixed-effects meta-regression and qualitative synthesis.

Results: In patients with UC (6 cohorts), 1-, 3- and 5-year risk of UC-related hospitalization was 10.4% (95% CI 8.2-13.2), 17.0% (95% CI 14.0-20.4) and 21.5% (95% CI 18.0-25.4), respectively, with considerable heterogeneity. In patients with CD (6 cohorts), 1-, 3- and 5-year risk of CD-related hospitalization was 29.3% (95% CI 20.0-40.8), 38.5% (95% CI 26.8-51.7) and 44.3% (95% CI 32.7-56.5), respectively, with considerable heterogeneity. On meta-regression, steady decline in risk of hospitalization was observed in patients diagnosed in a more contemporary era. Younger age at onset (both UC and CD), extensive colitis (UC), ileal-dominant CD, perianal CD and penetrating and/or stricturing behavior (CD) and early need for corticosteroids and immunosuppressive therapy (both UC and CD) were associated with increased risk of hospitalization.

Conclusion: Approximately one in five and one in two patients with UC and CD are hospitalized within 5 years of diagnosis, respectively. Population health management strategies are required to mitigate unplanned healthcare utilization.