[Association between epicardial fat volume and coronary artery calcification in patients with chronic kidney disease]

Objective: To evaluate whether epicardial fat volume (EFV) is related to coronary artery calcification in patients with chronic kidney disease(CKD). Method: Multi-slice computed tomography was performed in 30 healthy subjects and 120 patients with CKD. Cross-sectional tomographic cardiac slices from base to apex were traced semi-automatically using a Volume Viewer of AW4.3 off-line workstation, and EFV was measured by assigning Hounsfield units ranging from -250 to -30 HU to fat.The coronary artery calcification score was assessed by CaScoring software. High density lipoprotein cholesterol(HDL-C), low density lipoprotein cholesterol(LDL-C) and collecting the body mass index (BMI), dialysis route, history of diabetes and coronary artery disease were used to analyze the relationship between EFV and other risk factors in patients with CKD. Results: There were 60.8%(73/120) male (mean age 62.8 years) and 39.2%(47/120) female (mean age 66.6 years) in the patients cohort, 73.3%(88/120) patients had coronary artery disease, 55.8%(67/120) had diabetes, 21 patients were on peritoneal dialysis and 9 on hemodialysis. EFV was apparently higher in stage 4-5 D CKD group compared with the control group((140.03±54.71), (145.01±64.56)and (141.45±62.04) cm(3) vs.(92.42±39.56)cm(3), P=0.007, 0.015 and 0.001), was similar between CKD3 and control group, and EFV was significantly higher in peritoneal dialysis group than in hemodialysis group and in coronary artery disease group compared with no coronary artery disease group((140.67±70.31) cm(3) vs.(105.22±61.49) cm(3), P=0.002). EFV was obviously higher in diabetes group than no diabetes group((148.41±65.78) cm(3) vs.(110.53±62.37) cm(3), P=0.007). CACS was apparently increased in stage 3-5 CKD group compared with the control group(140.0 vs.4.3, P<0.001). (3)When the patients were divided into four groups according to the eGFR, EFV was positively associated with CACS(r(s)=0.539, P=0.004) in control group, and the association become more robust in patients with CKD5(r(s)=0.841, P<0.000 1). EFV was related to age(r=0.662, P=0.005), BMI(r=0.648, P=0.009)and HDL-C(r=-0.433, P=0.024), but not related to eGFR and LDL-C. EFV was related to CACS(r=0.427, R(2)=0.182 3, P<0.001). CACS was positively correlated to age and BMI (all P<0.05)and negatively correlated with eGFR(P<0.05). Conclusions: Measurement of EFV may provide another useful noninvasive indicator of coronary artery calcification in CKD patients.