Impact of Nonadherence to Any Antiplatelet Therapy After PCI With Drug-Eluting Stents on Critical Outcomes

Background

Lifelong antiplatelet therapy after percutaneous coronary intervention (PCI) with drug-eluting stents (DES) is strongly recommended. However, the extent and temporal variation in the risk of nonadherence to this recommendation remain unclear.

Objectives

The aim of this study was to investigate how nonadherence to any antiplatelet therapy after PCI affects critical cardiac events and whether this effect varies over time.

Methods

This cohort study analyzed Japanese nationwide insurance claims and health checkup records of working-age patients who underwent PCI with DES between April 2016 and March 2022. Nonadherence was defined as prescription coverage of antiplatelet therapy <50% within preceding 90 days. Landmark-time survival analysis with propensity-score matching was conducted every 5 days from 90th to 1,095th days after PCI. The primary outcome was a composite of all-cause death, myocardial infarction, or cardiopulmonary arrest. Results were synthesized to assess temporal variation in the risk magnitude.

Results

Among 40,902 patients (mean age, 58.3 ± 8.3 years; 5.5% women [2,240 of 40,902], median [IQR] follow-up: 653 days [Q1-Q3: 235-1,233 days]), nonadherence was observed in 1.18% (421 of 35,582) at 90 days and 4.70% (579 of 12,312) at 1,095 days after PCI. Critical cardiac events were more frequent in nonadherent patients (HR: 2.50 [95% CI: 1.92-3.26]; P < 0.001), with no significant temporal variation across landmark times.

Conclusions

Nonadherence to any antiplatelet therapy after PCI was associated with a more than 2-fold increase in critical cardiac events, irrespective of post-PCI timing throughout 3 years. These findings emphasize the need for sustained efforts by health care providers and patients to maintain drug adherence over a prolonged period.