In the US, the most common cause of death in adults with diabetes is coronary heart disease (1). While this is also true in adults without diabetes, heart disease is at least twice as common in patients with diabetes. The excess risk occurs with both insulin-dependent diabetes mellitus (IDDM) and non-insulin-dependent diabetes mellitus (NIDDM). Adults with diabetes are more likely than those without diabetes to have hypertension and dyslipidemia (low levels of high-density lipoprotein, high levels of triglycerides, and small dense low-density lipoprotein [LDL]), but some of the increased risk of heart disease associated with diabetes appears to be independent of these factors.

Hyperinsulinemia, or insulin resistance, has been the leading candidate for the risk factor that explains the excess risk of cardiovascular disease in patients with diabetes (2). This is compatible with studies showing that insulin covaries with dyslipidemia, central obesity, and—in some populations—hypertension (3-6). Because hyperinsulinemia (or insulin resistance) precedes the onset of diabetes (7), its role as a cardiovascular disease risk factor is also compatible with the observation that cardiovascular disease risk