Objective: To investigate lipoprotein levels and composition in well-treated type II diabetic patients.
Research design and methods: Cholesterol and triglyceride levels were measured in plasma, VLDL, LDL, and HDL in 120 type II diabetic patients in good to fair metabolic control (HbA1c, 7.2 +/- 1.6%) and in 30 normal control subjects. ApoAI, AII, B, CII, CIII, and E levels in plasma were also determined.
Results: The diabetic patients have significantly higher levels of mean plasma cholesterol (5.85 vs. 5.43 mM, P = 0.03), LDL triglycerides (0.41 vs. 0.31 mM, P = 0.003), and HDL triglycerides (0.24 vs. 0.19 mM, P = 0.02), whereas total triglycerides, VLDL cholesterol and triglycerides, LDL cholesterol, and HDL cholesterol are not significantly different from normal control subjects. ApoB (150 vs. 135 mg/dl, P = 0.02) and apoCIII (10.6 vs. 8.4 mg/dl, P = 0.01) are significantly higher in diabetic patients compared with control subjects. No significant differences are observed in all the parameters among diabetic patients treated with diet only, sulphonylurea, sulphonylurea plus biguanides, or insulin. Body weight is significantly related to VLDL lipids. The VLDL triglycerides are inversely related to the HDL cholesterol in both diabetic patients and control subjects. The VLDL triglycerides are directly related to the HDL triglycerides only in diabetic patients. No other lipid or lipoprotein parameters are significantly related to body weight or metabolic control.
Conclusions: Type II diabetic patients in good to fair metabolic control are characterized by minor alterations of the plasma lipids, but LDL and HDL triglycerides, apoB, and apoCIII are increased, thus indicating that the lipoprotein composition is altered, possibly because of an abnormal triglyceride metabolism and/or lipid transfer activity.