Background It is unknown whether clinical events identified with administrative claims have similar prognosis compared with trial-adjudicated events in cardiovascular clinical trials. We compared the prognostic significance of claims-based end points in context of trial-adjudicated end points in the DAPT (Dual Antiplatelet Therapy) study. Methods and Results We matched 1336 patients aged ≥65 years who received percutaneous coronary intervention in the DAPT study with the CathPCI registry linked to Medicare claims. We compared death at 21 months post-randomization using Cox proportional hazards models among patients with ischemic events (myocardial infarction or stroke) and bleeding events identified by: (1) both trial adjudication and claims; (2) trial adjudication only; and (3) claims only. A total of 47 patients (3.5%) had ischemic events identified by both trial adjudication and claims, 24 (1.8%) in trial adjudication only, 15 (1.1%) in claims only, and 1250 (93.6%) had no ischemic events, with annualized unadjusted mortality rates of 12.8, 5.5, 14.9, and 1.26 per 100 person-years, respectively. A total of 44 patients (3.3%) had bleeding events identified with both trial adjudication and claims, 13 (1.0%) in trial adjudication only, 65 (4.9%) in claims only, and 1214 (90.9%) had no bleeding events, with annualized unadjusted mortality rates of 11.0, 16.8, 10.7, and 0.95 per 100 person-years, respectively. Among patients with no trial-adjudicated events, patients with events in claims only had a high subsequent adjusted mortality risk (hazard ratio (HR) ischemic events: 31.5; 95% CI, 8.9‒111.9; HR bleeding events 23.9; 95% CI, 10.7‒53.2). Conclusions In addition to trial-adjudicated events, claims identified additional clinically meaningful ischemic and bleeding events that were prognostically significant for death.
Keywords: DAPT; claims; clinical trials; end points; prognosis.