Renal insufficiency and mortality in coronary artery disease with reduced ejection fraction

Abstract

BackgroundDespite strong evidence linking decreased estimated glomerular filtration rate (eGFR) to worse cardiovascular outcome, the impact of eGFR on mortality in coronary artery disease (CAD) patients with different left ventricular ejection fraction (EF) is not well defined. MethodsA retrospective cohort study. From Jul. 2008 to Jan. 2012, consecutive patients with CAD of West China Hospital were enrolled and were grouped into 3 eGFR categories: ≥90, 60–90, and <60mL/min/1.73m2. Patients with EF≥50% or <50% were defined as preserved EF or reduced EF, respectively. The endpoints were all-cause mortality and cardiac mortality. ResultsThere are 2161 patients according to the inclusion criteria and follow-up requirement. The mean follow-up time was 30.97±11.70months. Cumulative survival curves showed that in patients with reduced EF, renal insufficiency significantly increases all-cause mortality and cardiovascular mortality in a graded fashion (mortality rate, moderate or severe vs. normal: 29.3% vs. 5.4%, p<0.001; cardiac mortality rate, moderate or severe vs. normal: 18.2% vs. 4.5%, p=0.001, respectively). Cox regression analysis showed that in CAD patients with reduced EF, moderate to severe renal insufficiency increased all-cause mortality by 6.10-fold (HR 6.10, 95% CI 2.50 to 14.87) and cardiac mortality by 4.10-fold (HR 4.10, 95% CI 1.51 to 11.13). Use of beta-blockers, angiotensin converting enzyme inhibitors (ACEIs) or angiotensin receptor blockers (ARBs), and statins was associated with decreased risk of mortality, but the use was lower in renal insufficiency patients, especially in combination of reduced EF. ConclusionThis study has found that the effect of renal function on prognosis in patients with CAD is closely related to cardiac function. In patients with reduced EF, renal insufficiency accompanies the higher risks of all-cause mortality and cardiovascular mortality. A higher number of treatments from beta-blocker, ACEIs or ARBs, and statin therapy were associated with decreased risk of mortality, even in the combination of renal insufficiency or declining cardiac function.