Abstract
BACKGROUND AND OBJECTIVES: African-American race and decreased kidney function have been associated with higher mortality after acute myocardial infarction (AMI). However, whether there are racial differences in the prevalence or prognostic importance of renal insufficiency in AMI is unknown. DESIGN, SETTING, PARTICIPANTS & MEASUREMENTS: Among 1847 AMI patients enrolled in the multicenter Prospective Registry Evaluating Myocardial Infarction Event and Recovery (PREMIER) study, estimated glomerular filtration rate (eGFR) was used to stratify prognosis and to examine potential interactions among eGFR, race, and mortality. Multivariable proportional hazards regression was used to examine the effect of race and eGFR on 3.5-year all-cause mortality. RESULTS: Race and eGFR were significantly associated with mortality. After adjustment for eGFR alone, differences in mortality by race were substantially attenuated (unadjusted hazard ratio [HR] for African Americans=1.56 [95% confidence interval {CI}=1.2 to 2.1]; eGFR-adjusted HR=1.32 [95% CI=0.99 to 1.75]). A similar magnitude of attenuation in racial differences in survival was observed after adjustment for all covariates except eGFR (HR=1.29 [95% CI=0.96 to 1.72]). A final model adjusting for all covariates only slightly attenuated the association further. No interaction between race and eGFR was detected. CONCLUSIONS: Renal insufficiency, which may represent chronic kidney disease, is a prognostically important comorbidity in African Americans after AMI. However, the effect of decreased eGFR on mortality is comparable between races, suggesting that preventing renal insufficiency in African Americans could be an important target to reduce racial disparities in post-AMI survival.