Low-Density Lipoprotein Subfraction Phenotype Is Associated with Epicardial Adipose Tissue Volume in Type 2 Diabetes

Background: Increased epicardial adipose tissue (EAT) volume is a common feature in type 2 diabetes (T2DM) which is directly associated with heart failure and advanced atherosclerosis. We aimed to evaluate lipoprotein-related biomarkers of EAT volume in T2DM patients before and after glycemic control. Methods: This study included 36 T2DM patients before and after optimization of glycemic control and on 14 healthy controls (HCs). EAT volume was measured using computed tomography imaging indexed to the body surface area (iEAT). Biochemical and lipid profiles were determined using commercial methods. Lipoproteins were isolated by ultracentrifugation, and variables of lipoprotein function were assessed. Multivariable regression analysis was used to find variables independently associated with iEAT. Results: iEAT was higher in T2DM than in controls and decreased with glycemic optimization. HDLs from T2DM had less apoA-I and cholesterol and more apoC-III and triglycerides. LDLs from T2DM had more triglycerides and apoB and smaller sizes than those from HCs. Significant correlations were found between iEAT and age, BMI, HbA1c, GGT, VLDLc, triglycerides, LDL size, apoA-I in HDL, and apoC-III in HDL. In the multivariable regression analysis, age, LDL size, and GGT associations remained statistically significant, and predicted 50% of the variability in EAT volume. ROC analysis using these variables showed an AUC of 0.835. Conclusions: Qualitative characteristics of lipoproteins were altered in T2DM. Multivariable analysis showed that LDL size and GGT plasma levels were independently associated with iEAT volume, suggesting that these variables might be useful biomarkers for stratifying T2DM patients with increased EAT volume.