Underutilization of Mineralocorticoid Antagonists in Patients With Heart Failure With Reduced Ejection Fraction.

Background: It is unknown how the efficacy and safety of mineralocorticoid receptor antagonists vary according to duration of heart failure with reduced ejection fraction (HFrEF).

Objectives: In this study, we sought to evaluate the safety and efficacy of eplerenone according to duration of HFrEF.

Methods: In the EMPHASIS-HF trial, 3 patient groups were created according to HFrEF duration: <1 year, 1 to <5 years, and ≥5 years. The primary outcome was the composite of heart failure (HF) hospitalization or cardiovascular death. Outcomes were adjusted for prespecified prognostic variables and examined with the use of Cox regression models.

Results: The numbers of patients in each group were: 975, <1 year; 769, 1 to <5 years; and 988, ≥5 years. Patients with longer-standing HF were older and more frequently had cardiovascular and noncardiovascular comorbidities. The rate of the primary outcome (per 100 person-years) increased with HFrEF duration: 9.8 (95% CI: 8.4-11.4) for <1 year, 13.5 (95% CI: 11.6-15.7) for 1 to <5 years, and 17.6 (95% CI: 15.6-19.8) for ≥5 years. The benefits of eplerenone were consistent across HF duration: HRs for the primary outcome were 0.57 (95% CI: 0.42-0.79) for <1 year, 0.81 (95% CI: 0.60-1.10) for 1 to <5 years, and 0.61 (95% CI: 0.48-0.78) for ≥5 years; P = 0.24. The absolute benefit was greatest in the longest-duration group: the number needed to treat for the primary outcome was 14 for <1 year, 13 for 1 to <5 years, and 10 for ≥5 years duration.

Conclusions: Patients with longer-standing HFrEF had worse clinical status and a higher rate of events, but the benefit of eplerenone was consistent regardless of HFrEF duration. (A Comparison of Outcomes in Patients in NYHA Class II Heart Failure When Treated With Eplerenone or Placebo in Addition to Standard Heart Failure Medicines [EMPHASIS-HF]; NCT00232180).