Impaired Endothelium-Dependent Vasodilatation in Women With Previous Gestational Diabetes

Abstract

OBJECTIVE To assess whether otherwise healthy women with a history of gestational diabetes mellitus (GDM) may have abnormalities in endothelial function at a very early stage, before glucose intolerance occurs. RESEARCH DESIGN AND METHODS A total of 33 women with previous GDM (17 nonobese [BMI <27] and 16 obese [BMI ≥27]) and 19 healthy nonobese women were examined. A 75-g oral glucose tolerance test was performed, and insulin levels and biochemical parameters were also measured. Using high-resolution ultrasound, we measured vasodilatory responses of the brachial artery during reactive hyperemia (endothelium-dependent vasodilatation), and after nitroglycerin administration, an endothelium-independent vasodilator. RESULTS Flow-mediated dilatation (FMD) was significantly and equally decreased in both groups of women with previous GDM, compared with control subjects (1.6 ± 3.7% in the nonobese GDM group and 1.6 ± 2.5% in the obese GDM group vs. 10.3 ± 4.4% in control subjects, P <0.001). FMD correlated inversely with serum uric acid levels, BMI, serum total cholesterol, and basal insulin resistance (homeostasis model assessment). Nitrate-induced dilatation was significantly decreased only in the obeseGDM group compared with control subjects (21.4 ± 5.1 vs. 27.9 ± 9.5, P < 0.05). CONCLUSIONS Endothelial dysfunction, which is considered as a very early index of atherogenesis, is alreadypresent in both obese and nonobese women with a history of GDM, even when they have normal glucose tolerance.