ABSTRACT

Importance - Early cardiovascular and bleeding events after coronary stenting are associated with high risk of morbidity and mortality.

Objective - To assess the prognosis of cardiovascular and bleeding events occurring beyond 1 year after coronary stenting.

Design, Setting, and Participants - This secondary analysis is derived from data from the Dual Antiplatelet Therapy (DAPT) Study, a multicenter trial involving 220 US and international clinical sites from 11 countries. The study dates were August 2009 to May 2014. Individuals who underwent coronary stenting and completed 12 months of thienopyridine plus aspirin therapy without ischemic or bleeding events remained on an aspirin regimen and were randomized to continued thienopyridine therapy vs placebo for 18 additional months. Individuals were then followed up for 3 additional months while receiving aspirin therapy alone. The analysis began in August 2015.

Exposures - Ischemic events (myocardial infarction not related to stent thrombosis, stent thrombosis, and ischemic stroke) and bleeding events (Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Arteries [GUSTO] classification moderate or severe bleeding).

Main Outcomes and Measures - Ischemic events (myocardial infarction not related to stent thrombosis, stent thrombosis, and ischemic stroke) and bleeding events (GUSTO classification moderate or severe bleeding). Death at 21 months after randomization (33 months after coronary stenting).

Results - In total, 25 682 individuals older than 18 years with an indication for coronary stenting were enrolled, and 11 648 (mean age, 61.3 years; 25.1% female) were randomized. After randomization, 478 individuals (4.1%) had 502 ischemic events (306 with myocardial infarction, 113 with stent thrombosis, and 83 with ischemic stroke), and 232 individuals (2.0%) had 235 bleeding events (155 with moderate and 80 with severe bleeding). Among individuals with ischemic events, 52 (10.9%) died. The annualized mortality rate after an ischemic event was 27.2 (95% CI, 20.3-35.7) per 100 person-years. The cumulative incidence of death after an ischemic event among the total randomized study population was 0.5% (0.3% with myocardial infarction, 0.1% with stent thrombosis, and 0.1% with ischemic stroke). Among individuals with bleeding events, 41 (17.7%) died. The annualized mortality rate after a bleeding event was 21.5 (95% CI, 15.4-29.1) per 100 person-years. The cumulative incidence of death after a bleeding event among the total randomized study population was 0.3% (0.1% with moderate and 0.2% with severe bleeding).

Conclusions and Relevance - In patients treated with dual antiplatelet therapy for at least 1 year after coronary stenting, ischemic events were more frequent than bleeding events, and both events were associated with high risk of mortality.

Trial Registration - clinicaltrials.gov Identifier: NCT00977938