Association between Age and Complications after Outpatient Colonoscopy

Abstract

Importance: There are insufficient data describing the incidence and risk factors of postcolonoscopy complications in older individuals. Objective: To assess the association between older age (≥75 years) and the risk of postcolonoscopy complications. Design, Setting, and Participants: This population-based retrospective cohort study included adults (≥50 years) undergoing outpatient colonoscopy between April 2008 and September 2017, identified from Ontario administrative databases. Individuals with inflammatory bowel disease and hereditary colorectal cancer syndromes were excluded. The study population was subdivided into a colorectal cancer screening-eligible cohort (patients aged 50-74 years) and an older cohort (patients aged ≥75 years). The statistical analysis was conducted from December 2018 to September 2019. Exposures: Older age (≥75 years). Main Outcomes and Measures: The primary outcome was postcolonoscopy complications, defined as the composite of hospitalization or emergency department visits in the 30-day period after the outpatient colonoscopy. Secondary outcomes included incidence of surgically treated colorectal cancer and all-cause mortality at 30 days. Independent variables associated with postcolonoscopy complications were also assessed. Results: The study sample included 38069 patients; the mean (SD) age was 65.2 (10.1) years, there were 19037 women (50.0%), and 27831 patients (73.1%) underwent a first colonoscopy. The cumulative incidence of complications was 3.4% (1310 patients) in the overall population, and it was higher in individuals aged 75 years or older (515 of 7627 patients [6.8%]) than in screening-eligible cohort (795 of 30443 patients [2.6%]) (P