Diabetes
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Abnormalities in vascular reactivity in the micro- and macrocirculation are well established in type 2 diabetes. However, little is known about changes in vascular reactivity in those at risk for developing type 2 diabetes. To address this situation, the vascular reactivity in both the micro- and macrocirculation was studied in four age and sex comparable groups: 30 healthy normoglycemic subjects with no history of type 2 diabetes in a first-degree relative (controls), 39 healthy normoglycemic subjects with a history of type 2 diabetes in one or both parents (relatives), 32 subjects with impaired glucose tolerance (IGT), and 42 patients with type 2 diabetes without vascular complications (diabetes). ⋯ On stepwise multivariate analysis, age, sex, fasting plasma glucose, and BMI were the most important contributing factors to the variation of vascular reactivity. Addition of all clinical and biochemical measures explained only 32-37% of the variation in vascular reactivity. These results suggest that abnormalities in vascular reactivity and biochemical markers of endothelial cell activation are present early in individuals at risk of developing type 2 diabetes, even at a stage when normal glucose tolerance exists, and that factors in addition to insulin resistance may be operative.