Diabetes and Atherosclerosis

CONTEXT: Complications of atherosclerosis cause most morbidity and mortality in patients with diabetes mellitus. Despite the frequency and severity of disease, proven medical therapy remains incompletely understood and underused. OBJECTIVE: To review the epidemiology, pathophysiology, and medical and invasive treatment of atherosclerosis in patients with diabetes mellitus. DATA SOURCES: Using the index terms diabetes mellitus, myocardial infarction, peripheral vascular diseases, cerebrovascular accident, endothelium, vascular smooth muscle, platelets, thrombosis, cholesterol, hypertension, hyperglycemia, insulin, angioplasty, and coronary artery bypass, we searched the MEDLINE and EMBASE databases from 1976 to 2001. Additional data sources included bibliographies of identified articles and preliminary data presented at recent cardiology conferences. STUDY SELECTION: We selected original investigations and reviews of the epidemiology, pathophysiology, and therapy of atherosclerosis in diabetes. We selected randomized, double-blind, controlled studies, when available, to support therapeutic recommendations. Criteria for data inclusion (168 of 396) included publication in a peer-reviewed journal or presentation at a national cardiovascular society-sponsored meeting. DATA EXTRACTION: Data quality was determined by publication in peer-reviewed literature. Data extraction was performed by one of the authors. DATA SYNTHESIS: Diabetes mellitus markedly increases the risk of myocardial infarction, stroke, amputation, and death. The metabolic abnormalities caused by diabetes induce vascular dysfunction that predisposes this patient population to atherosclerosis. Blood pressure control, lipid-lowering therapy, angiotensin-converting enzyme inhibition, and antiplatelet drugs significantly reduce the risk of cardiovascular events. Although diabetic patients undergo revascularization procedures because of acute coronary syndromes or critical limb ischemia, the outcomes are less favorable than in nondiabetic cohorts. CONCLUSIONS: Since most patients with diabetes die from complications of atherosclerosis, they should receive intensive preventive interventions proven to reduce their cardiovascular risk.