Lipid-lowering therapy in diabetes mellitus

Dyslipidemia emerges as an important modifiable risk factor for cardiovascular disease in diabetes mellitus, especially as part of the metabolic syndrome in type 2 diabetes. In type 1 diabetes mellitus, tight glucose regulation usually will correct dyslipidemia. Both total cholesterol and triglyceride levels predict cardiovascular disease in diabetes, and HDL-cholesterol may prove to be an even better predictor. In type 2 diabetes, increased triglyceride and reduced HDL-cholesterol levels are the key characteristics of dyslipidemia. Increased hepatic VLDL production and impaired catabolism of triglyceride-rich particles contribute to hypertriglyceridemia. Subsequent formation of small dense LDL particles leads to increased atherogenicity. Small dense LDL particles have a longer circulation lime, are susceptible to glycoxidation, and are taken up by macrophages and the vessel wall. Post-hoc analysis of diabetic subgroups in primary and secondary prevention trials suggest that individuals with diabetes may enjoy substantial cardiovascular risk reduction from lipid-lowering therapy. Trials prospectively addressing the benefit of lipid lowering therapy in diabetes are under way. Target levels for lipid lowering therapy in diabetes at present stem from pathophysiological plausibility rather than from clinical proof. Intensive lipid-lowering with a statin in adequate dosage or a combination of a statin and a fibrate may be used to lower LDL-cholesterol levels to values < 2.6 mmol/l and triglyceride levels to < 1.7 mmol/l, a value at which few small dense LDL particles remain in circulation. Effective medication to raise HDL-cholesterol levels adequately are not yet available for clinical use. Treatment of diabetic dyslipidemia should be as simple as possible, given the polypharmacy that is often necessary for the patient with diabetes. Therefore, single treatment with a statin in adequate dosage is the first choice. (C) 2001 Elsevier Science B.V. All rights reserved.