Issue 152 Item 8 Hyperglycemia Plays A Key Role in Vascular Dysfunction

Despite differences in pathophysiology and metabolism, patients with type 1 and type 2 diabetes do not differ with respect to coronary vasodilator function. That, according to findings reported in the April 16th issue of the Journal of the American College of Cardiology. Thus, the study authors maintain, the common denominator — chronic hyperglycemia — likely plays a key role in the pathogenesis of vascular dysfunction.

Dr. Marcelo F. Di Carli and associates studied 18 subjects with type 1 diabetes, 17 with type 2 diabetes, and 11 age-matched control subjects. Diabetic subjects were asymptomatic, free of overt cardiovascular disease and similar in age and glycemic control.

Basal myocardial blood blow as measured by positron emission tomography was similar in the three groups.

During adenosine-induced hyperemia and during cold pressor testing, increases in blood flow did not differ significantly by type of diabetes but were markedly reduced compared with controls (p < 0.001). The differences persisted after adjusting for duration of diabetes, body mass index, lipid profile and autonomic neuropathy. ” Because the only thing these two groups have in common is hyperglycemia, then the hyperglycemia is probably the primary culprit for the abnormalities that one sees,” Dr. Di Carli, currently based at Brigham and Women’s Hospital, Boston, remarked in a press statement. It is “kind of scary,” he added, “because even when patients are in their 30s you can already see these impaired coronary blood flows as an early sign of atherosclerosis.” He recommended further study of the “synergy between hyperglycemia and insulin resistance.” J Am Coll Cardiol 2003;41:1387-1393. =============================== FOOD FACT: The Large Drink at McDonald’s in 1961 was 12 oz. The Large Drink at McDonald’s in 2003 is 44 oz