# The Risk of Colonoscopy‐related Bleeding in Patients With or Without Continued Treatment With an Antithrombotic Agent

## TL;DR

This study found that continuing antithrombotic treatment during colonoscopy does not significantly increase the risk of delayed bleeding, though immediate bleeding is more common.

## Contribution

The study provides new evidence on the safety of continuing antithrombotic therapy during colonoscopy procedures.

## Key findings

- Immediate bleeding was significantly more frequent in patients on antithrombotic treatment.
- Delayed bleeding after cold snare polypectomy was not significantly different between groups.
- Delayed bleeding after polypectomy was higher in patients on antithrombotic treatment.

## Abstract

We prospectively investigated the risk of colonoscopy‐related bleeding in relation to antithrombotic treatment.

This prospective, observational, single‐center cohort study (NCT02594813) enrolled consecutive patients who underwent colonoscopy, including the removal of colorectal polyps, regardless of the continuation of antithrombotic treatment. The primary outcome measure was delayed bleeding in the patients who underwent a hot snare polypectomy and/or endoscopic mucosal resection in addition to a cold snare polypectomy (CSP) and required endoscopic treatment ≤2 weeks after the procedure. Secondary outcomes were immediate bleeding and the number of hemostatic clips used during the procedure.

From January 2019 to December 2023 at our institution, 1562 (mean age 75 years) and 15,769 (mean age, 64 years) patients underwent colonoscopy with or without antithrombotic treatment, respectively. Immediate bleeding following the removal of colorectal polyps, regardless of the polypectomy technique, occurred in 173 (33.86%) of the 511 patients with antithrombotic treatment, which was significantly more frequent than in 439 (9.44%) of the 4651 patients without antithrombotic treatment (p < 0.001). On the other hand, there was no significant difference in delayed bleeding after CSP between the two groups (0.41% vs. 0.11%, p = 0.15). However, the incidence of delayed bleeding following polypectomy was significantly higher in patients receiving antithrombotic treatment compared to those without it (seven of 511 [1.37%] vs. 12 of 4651 [0.26%], p = 0.0016).

The risk of delayed bleeding after colonoscopy with removal of colorectal polyps was low despite continuation of antithrombotic therapy. www.clinicaltrials.gov (NCT02594813).