Body Composition and Mortality in Coronary Artery Disease With Mild Renal Insufficiency in Chinese Patients

Abstract

Obesity is a risk factor for both coronary artery disease (CAD) and chronic renal insufficiency (RI); patients with CAD are prone to obesity and RI. In this study, we try to analyze the effect of body composition on death in CAD patients with mild RI. Retrospective cohort study. A total of 1,591 consecutive CAD patients confirmed by coronary angiography were enrolled and met the mild RI criteria by estimated glomerular filtration rate: 60-90mL/min. The influence of body composition on mortality of CAD was detected in different body compositions, including body mass index (BMI), body fat (BF), and lean mass index (LMI). The end points were all-cause mortality. Cox models were used to evaluate the relationship of quintiles of body compositions with all-cause mortality. A survival curve showed that the risk of death was higher in the low BMI group than in the high BMI group (log-rank for overall P=.002); LMI was inversely correlated with risk of death, such that a lower LMI was associated with a higher risk of death (log-rank for overall P<.001). No significant correlation was observed between BF and risk of death. Multifactorial correction show that LMI was still inversely correlated with risk of death (quintile 1: reference; quintile 2: hazard ratio [HR]: 0.49, 95% confidence interval [CI]: 0.26-0.92; quintile 3: HR: 0.35, 95% CI: 0.17-0.70; quintile 4: HR: 0.41, 95% CI: 0.20-0.85; quintile 5: HR: 0.28, 95% CI: 0.12-0.67). For CAD patients with mild RI, BMI or BF was unrelated to risk of death, while LMI was inversely correlated with risk of death. A weak "obesity paradox" was observed in this study.