Abstract 2917: BNP Predicts Event-Free Survival in African American Patients with Moderate to Severe Heart Failure but does not Identify Responders to Fixed-dose Combination of Isosorbide Dinitrate / Hydralazine
Background: Brain Natriuretic Peptide (BNP), a central component of the counter-regulatory cardiac hormonal system, is a well-validated prognostic indicator of clinical worsening and survival in congestive heart failure. Some studies suggest that it can be utilized to identify patients who could benefit from intensification of heart failure therapies. Such a strategy has not been tested in African American patients who could benefit from the addition of a fixed-dose combination of isosorbide dinitrate and hydralazine (FDC I/H).
Methods: Baseline BNP levels measured in samples from frozen plasma (Biosite, San Diego CA) were analyzed in 694 participants from the African-American Heart Failure Trial (A-HeFT), a study of 1050 black patients with NYHA class III/IV heart failure who were randomized to a FDC I/H versus placebo. Kaplan-Meier method with log-rank test was used for analysis of event-free survival [death from any cause or first hospitalization for heart failure (HF)].
Results: A baseline BNP measure greater than median (156 pg/mL) was associated with a higher risk of death or first HF hospitalization (HR=2.58, 95% CI 1.91–3.42, p<0.0001). Patients with baseline BNP ≤100 pg/mL (n=281) had significantly increased event-free survival than the group with BNP >100 and ≤350 pg/mL (n=215) who in turn had increased event-free survival than the group with BNP >350 pg/mL (n=198), p<0.0001. Similar results were obtained when event-free survival was analyzed by baseline BNP quartiles (p<0.0001). Consistent with previous reports, an increase in event free survival was demonstrated in the cohort of patients with BNP measurement randomized to FDC I/H (HR= 0.58, 95%CI 0.44 – 0.78, p=0.0002). Despite the demonstrated prognostic value in this population, baseline BNP did not predict a clinical response in event-free survival to FDC I/H: patients with baseline BNP ≤ 100 pg/mL (HR=0.45, 95% CI 0.25– 0.83, p=0.010); patients with 100<BNP≤350 (HR=0.54, 95% CI 0.34 – 0.90, p=0.018); patients with BNP>350 (HR=0.73, 95% CI 0.47–1.14, p=0.170).
Conclusion: Although BNP remains a powerful prognostic marker in this study population of outpatient African Americans with NYHA class III/IV heart failure, the decision to treat HF with FDC I/H should not be based on BNP values.