Differences in patient outcomes after outpatient GI endoscopy across settings: a statewide matched cohort study

Background and Aims: Outpatient GI endoscopy has been shifting from hospital outpatient departments (HOPDs) to ambulatory surgery centers (ASCs) in recent years. However, evidence on whether patient outcomes after endoscopic procedures are comparable across settings is limited. This study compares the incidence of unplanned hospital visits after GI endoscopy performed in ASCs versus HOPDs. Methods: We conducted a retrospective cohort study examining unplanned hospital visits after outpatient GI endoscopy performed in Massachusetts during 2014 to 2017 using Massachusetts All-Payer Claims Database and Medicare fee-for-service claims. We identified screening colonoscopy, nonscreening colonoscopy, and esophagogastroduodenoscopies (EGD5) performed in ASCs or HOPDs and estimated unplanned hospital visit rates within 7 and 30 days after these procedures. To compare rates between ASCs and HOPDs, we constructed procedure-specific, propensity score-matched samples and used multilevel logistic regressions adjusting for patient, procedure, and facility characteristics. Results: Seven-day unplanned hospital visit rates were 10.6, 18.3, and 38.9 per 1000 procedures for screening colonoscopy, nonscreening colonoscopy, and EGD, respectively, with significant variation across facilities. ASC patients consistently had fewer postprocedure hospital encounters. The relative risk of having 7-day hospital visits after screening colonoscopy performed in ASCs was .88 (95% confidence interval [CI] , .79-.98) compared with HOPDs. The estimates were .84 (95% CI, .75-.94) for nonscreening colonoscopy and .57 (95% CI, .50-.65) for EGD. Thirty-day visits showed similar patterns. Conclusions: Unplanned hospital visits after outpatient GI endoscopy were not uncommon. However, ASC patients consistently had less frequent hospital-based acute care encounters, indicating that GI endoscopy could be performed safely in ASCs for select patients.