Do all antithrombotic agents have a similar impact on small bowel bleeding?

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Clin Endosc. 2025;58(1):80-81
Publication date (electronic) : 2025 January 24
doi : https://doi.org/10.5946/ce.2024.313
Department of Internal Medicine, Ewha Womans University College of Medicine, Seoul, Korea
Correspondence: Ki-Nam Shim Department of Internal Medicine, Ewha Womans University Seoul Hospital, Ewha Womans University College of Medicine, 260 Gonghang-daero, Gangseo-gu, Seoul 07804, Korea E-mail: shimkn@ewha.ac.kr
Received 2024 November 25; Revised 2024 December 31; Accepted 2025 January 1.

Antithrombotic agents, including anticoagulants and antiplatelet agents, are widely used therapeutically for the primary and secondary prevention of cardiovascular diseases. Even though action mechanisms might be distinct according to the antithrombotic agents, gastrointestinal bleeding (GIB) is a well-recognized major adverse event in patients receiving antithrombotic agents.1

In this issue of Clinical Endoscopy, Scaramella et al.2 reported a large European cohort study of 1,497 consecutive patients who underwent video capsule endoscopy (VCE) during 20 years in two centers in Italy and United Kingdom. In analyses of this cohort, the utility of VCE in diagnosing small bowel bleeding (SBB) was reaffirmed.2,3 The participants receiving antithrombotic agents in the study population had higher risk in SBB. Recent advancements in artificial intelligence (AI) have significantly improved the accuracy of VCE diagnosis and reduced the workload of interpreting endoscopy results.4 These AI-powered tools can assist clinicians in identifying subtle lesions, classifying abnormalities, and providing more accurate and consistent diagnoses. Furthermore, AI algorithms can analyze vast amounts of patient data to identify patterns and risk factors, potentially enabling personalized treatment approaches and improved patient outcomes.

Scaramella et al.2 reported that antithrombotic agents appeared to have a similar impact on SBB regardless of the number of medications used (monotherapy versus combined therapy) or their types (antiplatelet agents, direct oral anticoagulants [DOACs] or warfarin). However, the impact of different antithrombotic agents on SBB remains unclear. In a nationwide cohort study of 314,184 patients with atrial fibrillation, only apixaban was associated with a lower risk of major bleeding than warfarin and other DOACs. Both dabigatran and rivaroxaban were associated with a similar GIB compared to warfarin.5 Another retrospective study of 44,292 population found no differences between DOAC and warfarin in major bleeding events including intracranial, pericardial, and GIB, between DOACs and warfarin.6 A meta-analysis about bleeding risk comparison between dual antiplatelet agents and triple therapy (dual antiplatelet agent plus warfarin) demonstrated that triple therapy has a higher major bleeding risk than dual antiplatelet agents.7 Furthermore, a study using the United States of America nationwide claims database demonstrated that combination antithrombotic therapy substantially increase the risk of GIB when compared with anticoagulant monotherapy or antiplatelet monotherapy.8 Existing bleeding scores such as HAS-BLED,9 ATRIA,10 ORBIT,11 or DOAC Score12 assign varying weights to antithrombotic agents or antiplatelet agents. However, these scores do not specifically focus on the SBB. Therefore, the precise impact of different antithrombotic agents on SBB remains inconclusive.

Further research is needed to determine whether each antithrombotic agent exerts a distinct effect on SBB, identify the agents with the highest and lowest SBB risks, and optimize antithrombotic therapy based on individual patient risk stratification.

Notes

Conflicts of Interest

The authors have no potential conflicts of interest.

Funding

None.

Author Contributions

Conceptualization: CHT, KNS; Supervision: KNS; Writing–original draft: CHT; Writing–review & editing: all authors.

References

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