不同糖代谢状态下体重指数与胰岛β细胞功能的相关性

目的: 探讨不同糖代谢状态下体重指数(BMI)与胰岛β细胞功能的相关性。方法: 选取2013年在本院常规体检的2 082例人群为研究对象，采集体检者的人体学参数、75 g 口服葡萄糖耐量试验（2hOGTT）、空腹血糖、空腹胰岛素、血清尿酸等生化指标，按照血糖浓度将研究对象分为正常糖代谢组、糖代谢异常组及糖尿病组。按照BMI的水平将所有研究对象分为正常组、超重组和肥胖组，计算并比较3组HOMA稳态模型胰岛素抵抗指数（HOMA-IR）、胰岛β细胞功能（HOMA-β）及胰岛素敏感指数（HOMA-ISI）。结果： 糖尿病组的年龄、BMI、腰围、收缩压、舒张压、空腹血糖、空腹胰岛素、餐后2 h血糖、糖化血红蛋白、三酰甘油、总胆固醇、低密度脂蛋白等指标均明显高于其余两组，差异有统计学意义（P<0.05）。在非糖尿病人群中，HOMA-β和HOMA-IR随着BMI 的增大而增大（P<0.01），HOMA-ISI随着BMI 的增大而降低（P<0.01）；而在糖尿病患者中，HOMA-ISI随着BMI 的增大而降低（P<0.01），HOMA-β和HOMA-IR随BMI的变化趋势无统计学意义。 结论： 不同糖代谢状态下，BMI对胰岛β细胞功能的作用存在差别，在正常糖代谢和糖代谢异常人群中，BMI的增大可使胰岛β细胞功能代偿性增加，而糖尿病患者中这种代偿性机制已有一定程度的破坏。

Relationship between body mass index and islet β cell function under different glucose metabolisms in adults

Objective: To investigate the correlation between body mass index(BMI) and islet β cell function under different glucose metabolism conditions. Methods: We conducted a health examination survey for individuals who were randomly selected from residents living in the area of Xuzhou, China in 2013. A total of 2 082 subjects were included in the present study. Antheropometric measurements, 2-hour plasma glucose of 75 g oral glucose tolerance test(2hOGTT), fasting blood glucose, fasting insulin, serum uric acid and other biomarkers were collected. They were divided into normal glucose metabolism, abnormal glucose metabolism and diabetic group according to the blood glucose levels of the subjects. According to the level of BMI, they were divided into 3 groups: normal group, over weight and obese group.The Homeostasis Model Assessment-Insulin Resistance index (HOMA-IR), the Homeostasis Model Assessment of islet β cell (HOMA-β) and the Homeostasis Model Assessment-Insulin Sensitive index(HOMA-ISI) were calculated. Results: The level of age, BMI, waist circumference, systolic bloodpressure, diastolic blood pressure, fasting blood glucose, fasting insulin, 2hOGTT, HbA1c, triglycerides, total cholesterol, and LDL-c were higher in the diabetic group than those of the other two groups. And the difference was statistically significant(P<0.05). In non diabetic groups, HOMA-β and HOMA-IR were increased with the increase of BMI, but HOMA-ISI was decreased with the increase of BMI(P<0.01).While, in the diabetic group, HOMA-ISI was decreased with the increase of BMI(P<0.01),the trend of HOMA-β and HOMA-IR with BMI was not statistically significant. Conclusion: The association of BMI with the function of islet β cells depends on glucose metabolic conditions. In the normal glucose metabolism and abnormal glucose metabolism, higher BMI is associated with the increased islet β cell function. However this association disappeared in the diabetes mellitus. ［Key words］body mass index; insulin resistance; islet β cell; diabetes mellitus