不同糖调节受损人群胰岛β细胞功能和胰岛素反应敏感性评估的意义

Evaluation of islet β-cell-function and insulin response sensitivity in individuals with different impaired glucose regulation

目的探讨不同糖调节受损人群β细胞胰岛素分泌功能(β细胞功能)损害和胰岛素抵抗(IR)的特点,为糖尿病的一级预防提供理论依据。方法根据口服75 g葡萄糖耐量试验将200例研究对象分为:正常糖耐量(NGT)组37例;单纯空腹血糖受损(I-IFG)组35例;单纯糖耐量受损(I-IGT)组50例;混合糖调节受损(CGI)组33例;新诊断2型糖尿病(N2DM)组45例。采用HOMA-β和HOMA-IR评价基础β细胞功能和基础IR,△I30/△G30、△I60/△G60和△I120/△G120分别评价糖负荷后的早相和晚相β细胞功能,胰岛素敏感性指数(SIM)评价外周胰岛素反应敏感性。结果与NGT组比较,I-IFG组HOMA-β和△I30/△G30明显降低(均P<0.01),而HOMA-IR明显升高(P<0.01),两组间△I60/△G60、△I120/△G120和SIM无明显差异;I-IGT组△I30/△G30、△I60/△G60、△I120/△G120和SIM明显降低(P<0.05或P<0.01),而HOMA-β和HOMA-IR与NGT组无明显差异;CGI组HOMA-β、△I30/△G30、△I60/△G60、△I120/△G120和SIM均明显降低(P<0.05或P<0.01),而HOMA-IR明显升高(P<0.01);与N2DM组比较,I-IFG组、CGI组和I-IGT组HOMA-β均明显高于N2DM组(P<0.01),三组HOMA-IR均低于N2DM组(P<0.01),而△I30/△G30、△I60/△G60、△I120/△G120和SIM均高于N2DM组(均P<0.01)。结论 I-IFG人群主要为基础β细胞功能损害和基础IR增强,I-IGT人群以糖负荷后的早相和晚相胰岛素分泌功能缺陷以及外周胰岛素反应敏感性降低为主,而CGI人群则兼有基础和糖负荷后β细胞功能损害以及系统性IR增强。

[ Objective ] To investigate the characteristic of damaged islet β cell secretion insulin function （β-cell- function） and insulin resistance （IR） in individuals with different impaired glucose regulation, to provide theoretic foundation for first-degree prevention of diabetes mellitus. [Methods] According to oral 75 g glucose tolerance test （OGTT）, 200 subjects were divided into normal glucose tolerance （NGT, n =37）, isolated-impaired fasting glu- cose （I-IFG, n =35）, isolated-impaired glucose tolerance （I-IGT, n =50）, combined glucose intolerance （CGI, n=33） and newly diagnosis type 2 diabetes mellitus （N2DM, n =45）. HOMA-β and HOMA-IR were applied to assess the basic β-cell-function and basic IR, the ratio of insulin increment from 0 min to 30 min, 60 rain and 120 rain to that of blood glucose from 0 rain to 30 min, 60 min and 120 min （△I30/△G30, △I60/AG60 and△I120/△G120） were used to evaluate the early phase and_the late phase β-cell-function respectively, and SIM was adopted to evaluate the pc-ripheral tissue insulin sensitivity. [Results] As compared with NGT group,in I-IFG group,HOMA-β and △I30/ △G30 were lower （all P 〈0.01）, HOMA-IR was higher （P 〈0.01）, while △I60/△G60,△I120/△G120 and SIM were no difference; in I-IGT group, △I30/△G30, △I60/△G60,△I120/△G120 and SIM were lower （P 〈0.05 or P 〈0.01）, HOMA- and HOMA- IR were no difference; in CGI group, HOMA-β, △I30/△G30, △I60/△G60,△I120/△G120 and SIM were lower （P 〈0.05 or P 〈0.01）, and HOMA-IR was higher （P 〈0.01）, as compared with N2DM group, HOMA-15 was marked higher in I-IFG, I-IGT and CGI groups （all P 〈0.01）; while △I30/△G30, △I60/△G60,△I120/△G120 and SIM were marked higher （all P 〈0.01）, and HOMA-IR was marked lower （P 〈0.01） in three group. [ Conclusions] The individuals with I-IFG mainly showed damaged of basic β-cell-function and enhancement of basic IR, the individ- uals with I-IGT showed 15 cell secretion insulin function defect of all early and late phase during glucose load and reduction of the peripheral tissue insulin sensitivity, the individuals with CGI had dysfunction of basic and postprandial β-cell-function as well as enhancement of system IR, while the patients with N2DM in degree of im- paired β-cell- function and IR were more severe than individuals with IGR.