Increased Post-procedural Non-gastrointestinal Adverse Events After Outpatient Colonoscopy in High-risk Patients

The incidence and predictors of non-gastrointestinal (GI) adverse events (AEs) after colonoscopy are not well-understood. We studied the effects of antithrombotic agents, cardiopulmonary comorbidities, and age on risk of non-GI AEs after colonoscopy.

We performed a retrospective longitudinal analysis to assess the diagnosis, procedure, and prescription drug codes in a United States commercial claims database (March 2010-March 2012). Data from patients at increased risk (n = 82,025; defined as patients with pulmonary comorbidities or cardiovascular disease requiring antithrombotic medications) were compared with data from 398,663 average-risk patients. In a 1:1 matched analysis, 51,932 patients at increased risk, examined by colonoscopy, were compared with 51,932 matched (on the basis of age, sex, and comorbidities) patients at increased risk who did not undergo colonoscopy. We tracked cardiac, pulmonary, and neurovascular events 1-30 days after colonoscopy.

Thirty days after outpatient colonoscopy, non-GI AEs were significantly higher in patients taking antithrombotic medications (7.3%; odds ratio [OR], 10.75; 95% confidence interval, 10.13-11.42) or those with pulmonary comorbidities (1.8%; OR, 2.44; 95% confidence interval, 2.27-2.62) vs average-risk patients (0.7%) and in patients 60-69 years old (OR, 2.21; 95% confidence interval, 2.01-2.42) or 70 years or older (OR, 6.45; 95% confidence interval, 5.89-7.06), compared with patients younger than 50 years. The 30-day incidence of non-GI AEs in patients at increased risk who underwent colonoscopy was also significantly higher than in matched patients at increased risk who did not undergo colonoscopy in the anticoagulant group (OR, 2.31; 95% confidence interval, 2.01-2.65) and in the chronic obstructive pulmonary disease group (OR, 1.33; 95% confidence interval, 1.13-1.56).

Increased number of comorbidities and older age (older than 60 years) are associated with increased risk of non-GI AEs after colonoscopy. These findings indicate the importance of determining comorbid risk and evaluating antithrombotic management before colonoscopy.