Insulin resistance and islet ?-cell function in nondiabetic first-degree relatives of type 2 diabetes families / 重庆医科大学学报

ABSTRACT

Objective:To investigate insulin resistance(IR) and islet ?-cell function in nondiabetic first-degree relatives(FDR) of patients in type 2 diabetes(T2DM) families.Methods:195 FDR with impaired glucose regulation(FIGR group),232 FDR with normal glucose tolerance(FNGT group) and 161 NGT spouses of probands or siblings(NC group),which come from 251 T2DM families including at least two T2DM patients in Chongqing district,were selected.The subjects of FIGR group were divided into 3 groups isolated impaired fasting glucose(iIFG),isolated impaired glucose tolerance(iIGT) and combined IFG and IGT(IFG/IGT).For all subjects,75 gram oral glucose tolerance tests were conducted.Blood glucose,lipid-profile and insulin were assayed.Homeostasis model assessment of insulin resistance(Homa-IR) was used to estimate insulin resistance,and disposition index(DI) was used to evaluate islet ?-cell function(DI1=Homa-?/ Homa-IR,DI2=△I30/△G30/ Homa-IR).Results:(1)After adjustment of age,sex and body mass index(BMI),compared with NC group,systolic blood pressure and Homa-IR increased and DI1 decreased in FNGT group and the difference was significant(P﹤0.05).Systolic blood pressure,triglyceride,plasma glucose and serum insulin levels during OGTT and Homa-IR of FIGR group were higher than those of NC group;while Homa-?,△I30/△G30,DI1 and DI2 of FIGR group were lower,and the difference was significant(P﹤0.01).(2)iIGT and IFG/IGT had higher plasma glucose at 60min and 120min,serum insulin at 120min during OGTT compared with iIFG(P﹤0.01),and the difference was significant.Compared with iIGT,Homa-IR increased and Homa-?,DI1 decreased in iIFG and IFG/IGT,and the difference was significant(P﹤0.05).DI2 of iIFG,iIGT and IFG/IGT decreased in turn.DI2 of IFG/IGT was much lower than that of the two formers,and the difference was significant(P﹤0.01).Conclusion:Non-diabetic FDR of T2DM patients presented IR and disfunction of ?-cell.