Will Correction of Dyslipoproteinaemia Reduce Coronary Heart Disease Risk in Patients with Non-insulin-dependent Diabetes? Need for Trial Evidence

The incidence of atherosclerotic vascular disease is greatly increased in patients with non-insulin-dependent diabetes (NIDDM). The most frequent lipoprotein abnormalities in this type of diabetes are an increase in triglyceride-rich lipoproteins and a decrease in high-density lipoproteins. Hypertriglyceridaemia appears to be a stronger coronary heart disease risk factor in patients with NIDDM than in nondiabetic subjects. Plasma total and low-density lipoprotein cholesterol levels in NIDDM patients and nondiabetic subjects do not differ. Hypercholesterolaemia is, however, as powerful a predictor of coronary heart disease risk in diabetic patients as in nondiabetic subjects. In spite of this knowledge, there is to date no solid evidence to indicate whether correction of dyslipoproteinaemia in order to reduce coronary heart disease risk in patients with NIDDM is more, equally, or less beneficial than it is in nondiabetic subjects. The only available data come from post-hoc subgroup analyses of the Helsinki Heart Study and the Scandinavian Simvastatin Survival Study (4S). Other trials including patients with diabetes are in progress. Only one intervention trial (currently in its treatment phase), the Diabetes Atherosclerosis Intervention Study (DAIS), is specifically designed to examine the lipid hypothesis in patients with NIDDM.