Are the COMPASS trial results applicable on a broader population in the REACH registry?
External applicability of the COMPASS trial: an analysis of the reduction of atherothrombosis for continued health (REACH) registryLiterature - Darmon A, Bhatt DL, Elbez Y, et al. - Eur Heart J 2017; published online ahead of print
- Out of the 65531 patients in the REACH registry, 31873 patients comprised the study population with either CAD or PAD, and after applying the eligibility criteria, 16875 were COMPASS-eligible.
- There were important differences in baseline characteristics regarding age, gender, history of previous stroke or TIA, or history of remote MI between COMPASS-eligible and COMPASS participants. The rates of use of secondary prevention medications at baseline were higher in COMPASS participants.
- Based on the Recurrent Ischemic Event risk and Bleeding risk scores, COMPASS participants had a higher risk profile compared with the COMPASS-eligible patients in the REACH registry based on the Recurrent Ischemic Event risk score (12.1 ± 2.8 vs. 9.9 ± 2.4; P< 0.001) and Bleeding risk score (8.5 ± 2.2 vs. 7.2 ± 1.7; P< 0.001).
- Compared with COMPASS participants in the reference aspirin treatment arm, COMPASS-eligible patients in the REACH registry had a higher primary outcome event rate per 100 patients/year (4.2; 95% CI: 4.0-4.3 vs. 2.9; 95% CI: 2.6-3.2; P < 0,0001).
- The rates (per 100 patient/years) of all-cause mortality (3.2; 95% CI: 3.1–3.4 vs. 2.2; 95% CI: 1.9–2.4; P< 0,001] or CV death (1.9; 95% CI: 1.8–2.1 vs. 1.2; 95% CI: 1.0–1.3; P< 0.001) were also higher among COMPASS-eligible patients in REACH.
- The rate per 100 patient/years of HF hospitalization was 1.1 (95% CI: 0.8–1.1) in COMPASS participants, compared with 3.5% (95% CI: 3.2–3.8) at 1 year among COMPASS-eligible patients in REACH.
COMPASS-eligible patients represented a substantial part of the spectrum of stable CAD and PAD patients enrolled in the REACH registry. They had a higher risk of ischemic events compared with actual COMPASS participants in the aspirin alone treatment arm. These results should be interpreted with caution, due to important differences in the design between the 2 studies.