Study of the correlation between vascular dilation function and insulin resistance as well as serum adiponectin in patients with different rates of glucose metabolism

Abstract

Objective To study the correlation between serum adiponectin along with insulin resistanee and vascular dilation function in patients with different rates of glucose metabolism.Method A total of 83 patients aged 50-65 years,including 17 with normal glucose tolerance(NGT),22 with impaired fasting glucose (IFG),23 with impaired glucose tolerance(IGT)and 21 with diabetes(DM)were enrolled. Serum adiponectin was measured,and homeostasis model assessment for insulin resistance index (HOMA-IR)and B cell function index were used to evaluate the function of insulin secretion before and during oral glucose tolerance test(OGTr).The brachial artery responses to flow-mediated endothelium-dependent vascular dilation(EDVD)and nitroglycerin-mediated vascular dilation (EIVD) were evaluated by using the vascular ultrasound with high resolution.Results The serum adiponectin and EDVD decreased that the degrees of reduction from slightness to greatness were in turn from NGT,IFG,IGT to DM,whereas,the insulin resistance index (HOMA-IR) increased just in reverse order.Adiponectin was negatively associated with HOMA-IR(r=-0.353,P 0.05).In a multiple regression analysis with a stepwise manner to predict adiponectin concentration and EDVD.HOMA-IR was supposed to predict adiponectin concentration.Meanwhile APN but not HOMA-IR was used to predict EDVD(P<0.05).Condusions The decrease in serum adiponectin,endothelial dysfunction and insulin resistance can be observed in the early stage of impaired glucose metabolism. Serum adiponectin concentration appears to be associated with vascular function and insulin resistance.The association between serum adiponectin concentration and vascular function seems to be independence from its link with insulin resistance index. Key words: Adiponectin; Insulin resistance index; Vascular dilation function; Glucose metabolism