Compared with insulin-sensitive individuals, endothelium-dependent coronary vasomotion was diminished in insulin resistance (-56%), impaired glucose tolerance (-85%), and diabetes (-91% to -120%).
Cross-Sectional
Do progressive states of insulin resistance and type 2 diabetes impair coronary circulatory function compared to insulin-sensitive individuals?
Progressive worsening of endothelium-dependent coronary vasomotion occurs with increasing severity of insulin resistance, even before overt diabetes, highlighting early vascular dysfunction in metabolic disease.
BACKGROUND: Abnormal coronary endothelial reactivity has been demonstrated in diabetes and is associated with an increased rate of cardiovascular events. Our objectives were to investigate the presence of functional coronary circulatory abnormalities over the full spectrum of insulin resistance and to determine whether these would differ in severity with more advanced states of insulin resistance. METHODS AND RESULTS: Myocardial blood flow (MBF) was measured with positron emission tomography and 13N-ammonia to characterize coronary circulatory function in states of insulin resistance without carbohydrate intolerance (IR), impaired glucose tolerance (IGT), and normotensive and hypertensive type 2 diabetes mellitus (DM) compared with insulin-sensitive (IS) individuals. Indices of coronary function were total vasodilator capacity (mostly vascular smooth muscle-mediated) during pharmacological vasodilation and the nitric oxide-mediated, endothelium-dependent vasomotion in response to cold pressor testing. Total vasodilator capacity was similar in normoglycemic individuals (IS, IR, and IGT), whereas it was significantly decreased in normotensive (-17%) and hypertensive (-34%) DM patients. Compared with IS, endothelium-dependent coronary vasomotion was significantly diminished in IR (-56%), as well as in IGT and normotensive and hypertensive diabetic patients (-85%, -91%, and -120%, respectively). CONCLUSIONS: Progressively worsening functional coronary circulatory abnormalities of nitric oxide-mediated, endothelium-dependent vasomotion occur with increasing severity of insulin-resistance and carbohydrate intolerance. Attenuated total vasodilator capacity accompanies the more clinically evident metabolic abnormalities in diabetes.
Prior et al. (Tue,) conducted a cross-sectional in Insulin resistance, impaired glucose tolerance, and type 2 diabetes mellitus. Insulin resistance, impaired glucose tolerance, and type 2 diabetes mellitus vs. Insulin-sensitive individuals was evaluated on Total vasodilator capacity and endothelium-dependent vasomotion. Compared with insulin-sensitive individuals, endothelium-dependent coronary vasomotion was diminished in insulin resistance (-56%), impaired glucose tolerance (-85%), and diabetes (-91% to -120%).