Background: Renal impairment is an emerging prognostic indicator in heart failure (HF) patients. Despite known racial differences in the progression of both HF and renal disease, it is unclear whether the prognosis for renal impairment in HF patients differs by race. We sought to determine in HF patients the 1-year mortality risks associated with elevated creatinine and impaired estimated glomerular filtration rate (eGFR) and to quantify racial differences in mortality.
Methods and results: We retrospectively evaluated the National Heart Care Project nationally representative cohort of 53,640 Medicare patients hospitalized with HF. Among 5669 black patients, mean creatinine was 1.6+/-0.9 mg/dL, and 54% had an eGFR < or =60, compared with creatinine 1.5+/-0.7 mg/dL and 68% eGFR < or =60 in 47,971 white patients. Higher creatinine predicted increased mortality risk, although the magnitude of risk differed by race (interaction P=0.0001). Every increase in creatinine of 0.5 mg/dL was associated with a >10% increased risk in adjusted mortality for blacks, compared with >15% increased risk in whites (interaction P=0.0001), with the most striking racial disparities at the highest levels of renal impairment. Depressed eGFR showed similar racial differences (interaction P=0.0001).
Conclusions: Impaired renal function predicts increased mortality in elderly HF patients, although risks are more pronounced in whites. Distinct morbidity and mortality burdens in black versus white patients underscore the importance of improving patient risk-stratification, defining optimal therapies, and exploring physiological underpinnings of racial differences.