不同腹内脂肪/皮下脂肪比值的糖耐量正常人群胰岛素敏感性与胰岛β细胞分泌功能的研究

Insulin Sensitivity and Islet β Cell Function in Persons with Normal Glucose Tolerance and Different VA/SA Ratio

目的通过检测糖耐量正常人群的血糖、血脂、血清胰岛素水平,探讨不同腹内/皮下脂肪比值的糖耐量正常人群的胰岛素敏感性以及胰岛β细胞分泌功能。方法 104名糖耐量正常人群,根据中位数按腹内脂肪情况分两组,其中VA/SA<0.4组53例(男20例,女33例),VA/SA≥0.4组51例(男23例,女28例),所有受试者分别测量体质指数(BMI)、腰围(WHC),行75 g葡萄糖OGTT试验,采用葡萄糖氧化酶法测血糖,放免法测血清胰岛素。血清胆固醇(TC)、三酰甘油(TG)、高密度脂蛋白胆固醇(HDL-C)均采用Beckman公司的试剂,在Beckman全自动生化分析仪上进行测试。采用SIEMENS SOMATOM Sensation 16CT机定量测定腹部内脏脂肪和腹部皮下脂肪面积,计算VA/SA值以及葡萄糖曲线下面积(AUCglu)、胰岛素曲线下面积(AUCins),计算稳态模型胰岛素抵抗指数(HOMA-IR)、总体胰岛素敏感指数(WBISI)、定量胰岛素敏感性检测指数(QUCKI)指数来评估胰岛素敏感性,稳态模型β细胞功能(HOMA-β)、胰岛素分泌指数(△I/△G)来评估胰岛β细胞分泌功能。结果 (1)VA/SA≥0.4组TG、HDL-C、LDL-C、VLDL-C、apoA、apoB较VA/SA<0.4组差异有统计学意义(P<0.01),而两组间TC差异无统计学意义(P>0.05);(2)VA/SA≥0.4组HOMA-IR、WBISI、QUCKI、AUCglu、AUCins与VA/SA<0.4组比较,差异有统计学意义(P<0.01);而HOMA-β、△I/△G两组间差异无统计学意义(P>0.05);(3)WBISI、AUCins、AUCglu与VA/SA的相关性(r值分别为-0.460、0.460和0.446)相似,强于HOMA-IR、QUCKI指数与VA/SA的相关性(r值分别为0.315和-0.319),而HOMA-β、ΔI/ΔG与VA/SA无相关性(P>0.05)。结论腹型肥胖患者中胰岛素敏感性下降先于胰岛β细胞功能衰竭。

Objective To explore insulin sensitivity and isletβcell function in persons with normal glucose tolerance（NGT） and different ratios of visceral adipose tissue area to abdominal subcutaneous adipose tissue area（VA/SA）. Methods Totally 104 NGT persons,according to the median of VA/SA ratio,were divided as group A（VA/SA0.4,n=53,20 males and 33 females） and group B（VA/SA≥0.4,n=51,23 males and 28 females）.All the subjects were given examinations of body mass index（BMI）,waist circumstance（WC）,75 g oral glucose tolerance test（OGTT）;blood sugar by glucose oxidase method;serum insulin by radioimmunoassay;triglyceride（TC）,total cholesterol（TG）,and high density lipoprotein-cholesterol（HDL-C） by using Beckman reagents and automatic biochemistry analyzer;VA and SA by using SASIEMENS SOMATOM Sensation 16CT.VA/SA ratio,area under curve of glucose（AUCglu）,area under curve of insulin（AUCins）,whole body insulin sensitivity index（WBISI） quantitative insulin sensitivity check index（QUICKI）,and HOMA insulin resistance index（HOMA-IR） were calculated for assessment of insulin sensibility;and homeostasis model β-cell function（HOMA-β） and insulin secretion index（△I/△G） for assessment of β-cell function. Results The concentrations of TG,HDL-C,lower density lipoprotein-cholesterol（LDL-C）,very low density lipoprotein（VLDL-C）,apolipoprotein A（ApoA）,and apolipoprotein B（ApoB） were markedly higher in group A than in group B（P0.01）;but no statistically significant difference in TG was found between the two groups（P0.05）.The levels of HOMA-IR,WBISI,QUCKI,AUCglu,and AUCins were significantly higher in group A than in group B（P0.01）;while the differences in values of HOMA-β and △I/△G between the two groups showed no statistical significance（P0.05）.The correlations of WBISI,AUCins,and AUCglu with VA/SA（r=-0.460,0.460 and 0.446） were similar,being stronger than those of HOMA-IR and QUCKI with VA/SA（r=0.315 and-0.319）;however,no correlation of HOMA-β and ΔI/ΔG with VA/SA was found（P0.05）. Conclusion In patients with visceral obesity the decrease of insulin sensitivity goes before failure of pancreatic islet β cell function.