家族性Ⅱ型糖尿病家系中非糖尿病一级亲属的高胰岛素血症与胰岛素抵抗

Hyperinsulinemia and insulin resistance in nondiabetic first-degree relatives of patients in familial NIDDM pedigrees

目的探讨家族性非胰岛素依赖型糖尿病（ＮＩＤＤＭ）家系中非糖尿病（ＤＭ）一级亲属的血浆胰岛素水平及胰岛素敏感性。方法对家族性ＮＩＤＤＭ家系中非ＤＭ一级亲属９７人和健康对照５５人作标准口服葡萄糖耐量试验（ＯＧＴＴ），测定各时点的血糖和血浆胰岛素，并由此计算ＯＧＴＴ葡萄糖、胰岛素曲线下面积比（ＳＧＩ）和胰岛素敏感性指数（ＩＳＩ）来反映机体的胰岛素敏感性。结果在年龄、体重指数（ＢＭＩ）及性别构成比可比的条件下，非ＤＭ一级亲属的ＳＧＩ和ＩＳＩ低于正常对照组（Ｐ＜００１）；而ＯＧＴＴ的０、３０、６０、１２０分钟的血浆胰岛素值高于正常对照组（Ｐ＜００５及Ｐ＜００１）。相关分析显示，ＳＧＩ与ＩＳＩ呈显著正相关（ｒ＝０３９、０４１，Ｐ＜００１），而ＳＧＩ和ＩＳＩ均与ＢＭＩ呈显著负相关（ｒ值分别为０．３８、０３９、０３２、０２５，Ｐ＜００１或Ｐ＜００５）。此外，空腹血浆胰岛素在两组均与ＢＭＩ呈显著正相关（ｒ＝０３０、０３４，Ｐ＜００５）。结论家族性ＮＩＤＤＭ家系中非ＤＭ一级亲属存在高胰岛素血症，其胰岛素敏感性显著降低。

Objective To study plasma insulin level and insulin sensitivity of nondiabetic firstdegree relatives of patients in familial noninsulin dependent diabetes mellitus ( NIDDM ) pedigrees. Methods Standard oral glucose tolerance test(OGTT) was conducted in 55 healthy controls and 97 firstdegree relatives of NIDDM probands in familial NIDDM pedigrees. Plasma glucose and plasma insulin were determined at all phases after oral glucose load.Moreover,we calculated the glucose/insulin area ratio under the curve of OGTT ( SGI ) and the insulin sensitivity index (ISI) in all subjects to estimate their insulin sensitivity. Results In nondiabetic firstdegree relatives,SGI and ISI were significantly decreased (P<001 ), and plasma insulin was increased at 0, 30, 60, 120 minutes after administration of oral glucose load (P<005 and P<001), as compared with the controls, in matched age, body mass index (BMI) and proportion of sex. In both firstdegree relatives and the insulin controls, SGI was positively correlated with ISI ( r=0.39, 0.41, respectively, P<0.01 ) and both SGI and ISI were inversely correlated with BMI (r=0.38,0.39; 0.32, 0.25, respectively, P<0.01). Moreover,FINS in the two groups was positively correlated with BMI (r=0.30,0.34,respectively, P<005). Conclusion In nondiabetic firstdegree relatives of patients in familial NIDDM pedigrees, plasma insulin level was increased and insulin sensitivity was decreased as compared with the healthy controls. It suggests that they suffered from hyperinsulinemia and insulin resistance.