Gastrointestinal Injury Caused by Aspirin or Clopidogrel Monotherapy Versus Dual Antiplatelet Therapy

Patients who undergo percutaneous coronary intervention (PCI) with drug-eluting stents require dual antiplatelet therapy (DAPT) for at least 6 months for stable ischemic heart disease (SIHD) or 12 months for acute coronary syndromes (ACS) to prevent stent thrombosis and other cardiovascular events (1). The rationale for using DAPT is that aspirin and a P2Y12 antagonist (such as clopidogrel, prasugrel, or ticagrelor) separately inhibit the c (COX-1) and the adenosine diphosphate–dependent pathways, and together confer greater protection against platelet activation and stent thrombosis than either antagonist alone. Unfortunately, DAPT approximately doubles the risk of gastrointestinal (GI) bleeding compared with single antiplatelet therapy (SAPT) (2). Mounting evidence suggests that a short course of DAPT followed by SAPT reduces bleeding without increasing ischemic events in patients with either stable ischemic heart disease (SIHD) SIHD or acute coronary syndromes ACS (3), but it is uncertain whether using either aspirin or a P2Y12 antagonist alone reduces GI injury. To compare the separate and combined GI effects of aspirin and clopidogrel, Han et al (4) performed serial capsule endoscopy (CE) after treatment with 3 different antiplatelet regimens in patients who underwent PCI predominantly for ACS The 3 regimen are as follows - SAPT using low-dose aspirin alone (n = 168) or clopidogrel alone (n = 169) or to DAPT using low-dose aspirin plus clopidogrel (n = 168) for an additional 6 months. In the study , almost every patient had erosions in the stomach or small intestine on every CE study (especially the last one), and 83% of patients had some evidence of GI injury at baseline despite the fact that 39% of patients were not on antiplatelet therapy before admission but were presumably on DAPT for the 30-120 hours from PCI to the time of CE. When the analysis focused on the subgroup of 68 patients without erosions, ulcers, or bleeding on the prerandomization CE, the investigators found that SAPT caused less GI mucosal injury (68.1% vs 95.2%; P = 0.006), including fewer new ulcers (8.5% vs 38.1%; P = 0.009), than did DAPT The investigators found that the secondary endpoint of any type of GI bleeding between 6 and 12 months was less with SAPT compared with DAPT (0.6% vs 5.4%; P = 0.001), without an increase in ischemic events . Moreover, overt GI bleeding was 90% lower with SAPT than with DAPT relative risk [RR]: 0.10. The other secondary outcome of clinically overt bleeding at any site, which was primarily Bleeding Academic Research Consortium 1, was also lower with SAPT than with DAPT (RR: 0.50), which was similar to the treatment effect reported in most contemporary trials evaluating SAPT after a short course of DAPT. Disclaimer: Lupin makes no representation or warranty of any kind, expressed or implied, regarding the accuracy, adequacy, validity, reliability, availability, or completeness of any scientific information shared by the HCP on the ­­­STAR UPDATE podcast. You should not allow the contents of this to substitute for your own medical judgment, which you should exercise in evaluating the information on this website.