Reduced kidney function and anemia as risk factors for mortality in patients with left ventricular dysfunction

OBJECTIVES We sought to evaluate the relationship between the level of kidn ey function, level of hematocrit and their interaction on all-cause mortali ty in patients with left ventricular (LV) dysfunction. BACKGROUND Anemia and reduced kidney function occur frequently in patients with heart failure. The level of hematocrit and its relationship with renal function have not been evaluated as risk factors for mortality in patients with LV dysfunction. METHODS We retrospectively examined the Studies Of LV Dysfunction (SOLVD) d atabase. Glomerular filtration rate (GFR) was predicted using a recently va lidated formula. Kaplan-Meier survival analyses were used to compare surviv al times between groups stratified by level of kidney function (predicted G FR) and hematocrit. Cox proportional-hazards regression was used to explore the relationship of survival time to level of kidney function, hematocrit and their interaction. RESULTS Lower GFR and hematocrit were associated with a higher prevalence o f traditional cardiovascular risk factors. In univariate analysis, reduced kidney function and lower hematocrit, in men and in women, were risk factor s for all-cause mortality (p < 0.001 for both). After adjustment for other factors significant in univariate analysis, a 10 ml/min/1.73 m(2) lower GFR and a 1% lower hematocrit were associated with a 1.064 (95% CI: 1.033, 1.0 96) and 1.027 (95% CI: 1.015, 1.038) higher risk for mortality, respectivel y. At lower GFR and lower hematocrit, the risk was higher (p = 0.022 for th e interaction) than that predicted by both factors independently. CONCLUSIONS Decreased kidney function and anemia are risk factors for all-c ause mortality in patients with LV dysfunction, especially when both are pr esent. These relationships need to be confirmed in additional studies. (C) 2001 by the American College of Cardiology.