Racial Differences in Diuretic Efficiency, Plasma Renin, and Rehospitalization in Subjects With Acute Heart Failure

Abstract

Background: Black patients have higher rates of hospitalization for acute heart failure than other race/ethnic groups. We sought to determine whether diuretic efficiency is associated with racial differences in risk for rehospitalization after acute heart failure.

Methods: A post hoc analysis was performed on 721 subjects (age, 68±13 years; 22% black) enrolled in 3 acute heart failure clinical trials: ROSE-AHF (Renal Optimization Strategies Evaluation in Acute Heart Failure), DOSE-AHF (Diuretic Optimization Strategy Evaluation in Acute Decompensated Heart Failure), and CARRESS-HF (Cardiorenal Rescue Study in Acute Decompensated Heart Failure). Repeated-measures ANOVA was used to test for a race×time effect on measures of decongestion. Diuretic efficiency was calculated as net fluid balance per total furosemide equivalents. In a subset of subjects, Cox regression was used to examine the association between race and rehospitalization according to plasma renin activity (PRA).

Results: Compared with nonblack patients, black patients were younger and more likely to have nonischemic heart failure. During the first 72 to 96 hours, there was greater fluid loss (P=0.001), decrease in NT-proBNP (N-terminal pro-B-type natriuretic peptide; P=0.002), and lower levels of PRA (P<0.0001) in black patients. Diuretic efficiency was higher in black than in nonblack patients (403 [interquartile range, 221-795] versus 325 [interquartile range, 154-698]; P=0.014). However, adjustment for baseline PRA attenuated the association between black race and diuretic efficiency. Over a median follow-up of 68 (interquartile range, 56-177) days, there was an increased risk of all-cause and heart failure-specific rehospitalization in nonblack patients with increasing levels of PRA, while the risk of rehospitalization was relatively constant across levels of PRA in black patients.

Conclusions: Higher diuretic efficiency in black patients with acute heart failure may be related to racial differences in activity of the renin-angiotensin-aldosterone system.

Keywords: disparities; diuretics; heart failure; humans; race factors; renin.

Figure 1.

Net fluid loss (A), and change in weight (B), serum creatinine (C), NT-pro BNP (D), systolic blood pressure (E) and diastolic blood pressure (F) during the first 72 hours after randomization by racial group.

Figure 2.

Distribution of diuretic efficiency by racial group.

Figure 3.

Change in serum PRA (A) and aldosterone (B) levels during the first 72 to 96 hours after randomization by racial group. Biomarkers are log-transformed for analysis.

Figure 4.

Plot of hazard of all-cause and HF-specific rehospitalization according to racial group and baseline PRA.

Figure 4.

Plot of hazard of all-cause and HF-specific rehospitalization according to racial group and baseline PRA.