Importance: Gastrointestinal injury progression induced by antiplatelet therapy in patients after percutaneous coronary intervention (PCI) has not been well studied.
Objective: To assess the association of aspirin, clopidogrel, and their combination with gastrointestinal injury progression among patients without high bleeding risk after PCI.
Design, setting, and participants: This secondary analysis assessed data from the Optimal Antiplatelet Therapy for Prevention of Gastrointestinal Injury Evaluated by ANKON Magnetically Controlled Capsule Endoscopy (OPT-PEACE) double-masked, placebo-controlled, multicenter randomized clinical trial. The OPT-PEACE trial was conducted at 28 centers in China, and recruitment took place from July 13, 2017, to July 13, 2019. The trial included patients with stable coronary artery disease or acute coronary syndromes without ST-segment elevation after PCI. Statistical analysis was conducted from September 13, 2022, to January 23, 2023.
Interventions: Patients underwent magnetically controlled capsule endoscopy (MCE) at baseline and after 6 months of dual antiplatelet therapy (DAPT) with aspirin (100 mg/d) plus clopidogrel (75 mg/d). Those with no evidence of gastrointestinal ulcers or bleeding (ie, the intention-to-treat [ITT] cohort) were randomized (1:1:1) to aspirin (100 mg/d) plus matching placebo (aspirin alone), clopidogrel (75 mg/d) plus matching placebo (clopidogrel alone), or DAPT for an additional 6 months. A third MCE was performed 12 months after PCI.
Main outcomes and measures: The primary outcome was the rate of gastric injury progression as assessed with the results of the 3 MCEs (at baseline, 6 months, and 12 months) in the modified intention-to-treat (mITT) population. The key secondary outcome was the rate of small-intestinal injury progression. Gastric or small-intestinal injury progression was defined as a quantitative increase in erosions or ulcers between the second and third MCEs (at 6 and 12 months, respectively).
Results: This study included the 394 patients in the mITT cohort. Their mean (SD) age was 56.9 (8.7) years, and most were men (296 [75.1%]). A total of 132 patients were randomized to aspirin alone, 132 to clopidogrel alone, and 130 to DAPT. Gastric injury progression occurred in 49 aspirin users (37.1%), 64 clopidogrel users (48.5%), and 69 DAPT users (53.1%) (P = .02), reflecting a lower rate of gastric injury progression among aspirin users vs DAPT users (risk ratio [RR], 0.70 [95% CI, 0.49-0.99]; P = .009). No significant difference was observed between clopidogrel alone and DAPT (48.5% vs 53.1%; P = .46) or between aspirin alone and clopidogrel alone (37.1% vs 48.5%; P = .06). A total of 51 aspirin users (38.6%), 65 clopidogrel users (49.2%), and 71 DAPT users (54.6%) (P = .03) developed progressive small-intestinal injury, reflecting a lower rate of small-intestinal injury among aspirin users vs DAPT users (RR, 0.71 [95% CI, 0.50-0.99]; P = .01). No difference was observed between patients treated with clopidogrel vs DAPT (49.2% vs 54.6%; P = .38) or with aspirin vs clopidogrel (38.6% vs 49.2%; P = .08).
Conclusions and relevance: In this secondary analysis of a randomized clinical trial, ongoing use of aspirin, clopidogrel, or their combination between 6 and 12 months after PCI was associated with progressive gastric and small-intestinal injury in a substantial proportion of patients, more so with DAPT than with monotherapy. Clopidogrel was at least as likely as aspirin to induce gastrointestinal injury progression. Future research is warranted to determine what impact the findings from MCEs would have on decision-making of antiplatelet therapy.
Trial registration: ClinicalTrials.gov Identifier: NCT03198741.