P2Y12 Inhibitor Monotherapy vs Dual Antiplatelet Therapy by Age After PCI: A SHARE Substudy

Abbreviated dual antiplatelet therapy (DAPT) followed by P2Y12 inhibitor monotherapy is increasingly used after percutaneous coronary intervention, but whether its effects are consistent across age is uncertain.

The authors examined age-related differences in outcomes with P2Y12 inhibitor monotherapy vs 12-month DAPT after percutaneous coronary intervention.

This post hoc analysis of the Short-Term DAPT After Deployment of Bioabsorbable Polymer Everolimus-Eluting Stent randomized trial stratified 1,387 patients at age 75 years. The primary endpoint was net adverse clinical events (NACE)-major bleeding (Bleeding Academic Research Consortium type 3 or 5) plus major adverse cardiac and cerebrovascular events-through 12 months.

Median follow-up was 365 days (Q1-Q3: 353-365); 210 patients (15.1%) were ≥75 years. NACE occurred in 25 of 1,177 patients <75 years (2.4%; 95% CI: 1.4-3.3) and 7 of 210 aged ≥75 years (3.7%; 95% CI: 1.0-6.4). NACE did not differ between monotherapy and 12-month DAPT in patients <75 years (8 of 587 [1.6%; 95% CI: 0.5-2.8] vs 17 of 590 [3.1%; 95% CI: 1.6-4.6]; HR: 0.47; 95% CI: 0.20-1.09) or ≥75 years (3 of 107 [3.3%; 95% CI: 0.0-6.9] vs 4 of 103 [4.2%; 95% CI: 0.1-8.1]; HR: 0.71; 95% CI: 0.16-3.17), with no treatment-age interaction (P = 0.637 dichotomized; P = 0.173 continuous). Major bleeding increased with age, whereas major adverse cardiac and cerebrovascular events remained stable.

P2Y12 inhibitor monotherapy after 3-month DAPT was associated with similar net clinical outcomes to 12-month DAPT in both younger and older patients, with no significant treatment-age heterogeneity. These findings support consideration of abbreviated DAPT as a reasonable treatment option in selected older adults, although larger studies are needed.

ClinicalTrials.gov Identifier NCT03447379.