Long-Term Outcomes of Aspirin vs. Clopidogrel After PCI in High-Risk Patients With Cardiovascular Comorbidities: A Post Hoc Analysis of the HOST-EXAM Extended Trial.

Abstract

Background and objectives: The HOST-EXAM Extended trial demonstrated the long-term benefits of clopidogrel over aspirin monotherapy following dual antiplatelet therapy (DAPT) after percutaneous coronary intervention (PCI). This sub-study evaluated these therapies in patients with and without previous cardiovascular disease (CVD).

Methods: A total of 5,438 patients were randomized to aspirin (100 mg daily) or clopidogrel (75 mg daily) monotherapy. Previous CVD was defined as previous myocardial infarction, cerebrovascular accident, or peripheral artery disease, present in 1,137 patients; 4,301 had no CVD. The primary endpoint was a composite of all-cause death, non-fatal myocardial infarction, stroke, readmission due to ACS, and major bleeding (Bleeding Academic Research Consortium [BARC] type 3 or 5). Secondary endpoints included thrombotic and any bleeding events (BARC type ≥2). Median follow-up was 5.8 years.

Results: The primary endpoint occurred more frequently in patients with previous CVD than in those without (18.1% vs. 13.7%, hazard ratio [HR], 1.045; 95% confidence interval [CI], 1.037-1.054; p<0.001). Regarding the treatment estimates for the primary endpoint between those with and without previous CVD, no significant interaction was observed (CVD group: HR, 0.784; 95% CI, 0.596-1.033 and non-CVD group: HR, 0.794; 95% CI, 0.675-0.934, respectively; interaction p=0.951). For thrombotic and bleeding composite endpoints, CIs were overlapping across CVD strata, indicating no clear heterogeneity.

Conclusions: Clopidogrel was associated with a lower risk of the primary endpoint versus aspirin after PCI, with no evidence of effect modification by previous CVD.