The reduced levels of high-density lipoprotein (HDL) 2-cholesterol (C) in diabetes and other metabolic disorders associated with a high risk of cardiovascular disease are well established. Few studies, however, have compared the HDL subspecies in type 1 diabetes (T1D) with those in type 2 diabetes (T2D) with or without insulin. We examined HDL subspecies in 27 T1D with insulin, 33 T2D with insulin or insulin plus oral-anti-diabetic drugs (OADs), 36 T2D with OADs or diet/exercise, and 25 non-diabetic controls. Insulin was injected four times daily in a basal-bolus manner for both T1D and T2D. Plasma levels of C, apolipoprotein (apo) AI, and AII were determined in HDL2 and HDL3 by the single precipitation method. HDL-C levels were significantly higher in T1D and lower in T2D, compared with the controls. Insulin-treated T2D had higher HDL-C than non-insulin-treated T2D. T1D had higher HDL2-C and HDL2-apo AI levels than T2D. Insulin-treated T2D had higher HDL2-C and HDL2-apo AI levels than non-insulin-treated T2D. All of these differences were more pronounced for men than for women. HDL3 levels were comparable among controls,T1D and T2D. HDL2-C levels were inversely associated with BMI, HbA1c, triglyceride, small dense LDL-C, and LDL-C. Multiple regression analysis revealed that HDL2-C was independently associated with triglyceride, LDL-C, and intensive insulin therapy but not with HbA1c. In conclusion, these results suggest that intensive insulin therapy is associated with alterations of HDL subspecies, irrespective of the type of diabetes.
The Japan Endocrine Society