21 NATURAL HISTORY OF COLECTOMY AMONG HOSPITALIZED PATIENTS WITH ULCERATIVE COLITIS IN THE CONTEMPORARY ERA OF BIOLOGICS

Abstract

Abstract BACKGROUND Despite reducing mortality, the use of intravenous (IV) corticosteroids has not significantly reduced inpatient colectomy rates among hospitalized patients with ulcerative colitis (UC). Whether the occurrence of colectomy, estimated at 20–30% in this population in the prebiologic era, remains elevated is unknown. Methods A retrospective cohort study was conducted among health plan members of an integrated health care delivery organization that serves approximately 4.0 million members in urban, suburban, and semi-rural regions throughout Northern California. The study population consisted of 524 health plan members age >18 years of age with a 1) diagnosis of ulcerative colitis (ICD-9 code 556; ICD-10 code K51); 2) first hospitalization between 2009 and 2017 coded with ulcerative colitis as the primary cause for admission; 3) no prior hospitalizations for UC; 4) at least 1 year of continuous membership prior to the index hospitalization; 5) No dispensing of biologic therapy (infliximab, adalimumab, golimumab, vedolizumab) recorded prior to hospitalization; 6) No record of Clostridium difficile or cytomegalovirus infection during the hospitalization or 30 days prior. The primary outcome was the occurrence of colectomy during the index hospitalization and up to 12 months after hospitalization. Additional outcomes assessed were trends in colectomy over this time period and predictors for colectomy during the index hospitalization. Results A total of 5.3% of UC patients underwent colectomy during the index hospitalization (95%CI 3.3–7.3%) and 11.9% underwent colectomy within the first year after hospitalization (95% CI: 9.1–14.6%). Inpatient colectomy declined from 6.5% (95%CI: 2.5–10.6%) in 2009–2010 to 3.4% (95%CI: 3.3–7.3%) in 2015–2017. Colectomy in the first year after admission declined from 15.7% (95%CI 10.0–21.4%) in 2009–2011 to (10.1%; 95% CI: 5.4–14.7) in 2015–2017. A total of 16.3% of patients received infliximab in the hospital and 36.3% received within the first year of admission. In a multivariable model, the 2015–2017 cohort experienced a 64% reduction in inpatient colectomy compared to the 2009–2011 cohort (OR 0.36; 95%CI: 0.11–1.14, p=0.082) and a 54% reduction in colectomy in the first year (OR 0.46; 95%CI: 0.22–0.96, p=0.038). A prior study between 1998–2004 in this same population showed colectomy rates of 20% during the index hospitalization and 30% at 1 year. Conclusion Colectomy within the first year after hospital admission for UC has declined over time in the modern era of biologics with a magnitude of colectomy that is lower than the historical rate of 20–30%. Our data imply cause for optimism that the natural history of colectomy in acute severe UC may be different and modifiable in the modern biologic era compared to the past.