Plasma Lipids and Lipoproteins, and Basal Insulin Levels in Type II Diabetes Mellitus under Treatment

The purpose of this study was the simultaneous measurement of triglyceride, total cholesterol, phospholipid, very low density lipoprotein cholesterol (VLDL-C), low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C) and basal insulin levels from carefully selected patients with diabetes mellitus who were under treatment for a long period (7.2±0.8yr.).Subjects included patients with middle-aged type II diabetes (51.2±0.8yr.: Group A) together with healthy individuals matched for sex, age and body weight (47.8±1.6yr.: Group B). In diabetic patients, all the above-mentioned variables were examined according to the difference of blood sugar control, treatments for diabetes mellitus, and the existence of diabetic retinopathy. Furthermore, it was studied that the relationship betweenthese variables and the existence of ischemic heartdisease (IHD) in old type II diabetes (69.8±1.8yr.: Group C).1) Fasting plasma glucose in Group A was significantly elevated compared with that in Group B (p<0.01). No difference in plasma lipids, lipoproteins and basal insulin levels was found between Group A and B. But triglyceride and LDL-C/HDL-C ratio showed a tendency to increase in Group A.2) Diabetic patients treated with insulin showed elevated fasting plasma glucose and basal insulin level compared with patients of groups treated either with sulfonylurea or diet only (p<0.05, p<0.05; respectively). And the patients treated with sulfonylurea or insulin showed a tendency to increase of HDL-C compared with the diet therapy patients.3) Total cholesterol, triglyceride LDL-C and HDL-C increased more in the groups with advanced hyperglycemia. So, LDL-C/HDL-C ratio did not differ according to blood sugar control.4) The group of patients with proliferative retinopathy showed significantly elevated triglyceride level compared with groups of patients either with background retinopathy or without retinopathy (p<0.05, p<0.05; respectively). No significant difference in other lipids, lipoproteins was observed among these three groups.5) Triglyceride, LDL-C and LDL-C/HDL-C ratio showed a tendency to increase in Group C compared with those in Group A. Furthermore, patients with IHD showed a tendency to still more elevated level compared with those without IHD in Group C. But no difference in other lipids and lipoproteins was found between patients with IHD and without IHD.From these data, it was thought that correction of plasma lipids and lipoproteins as well as plasma glucose level was very important to prevent against both arteriosclerosis and microangiopathy with diabetes mellitus.