体质指数对2型糖尿病一级亲属进行糖尿病筛查的预测价值

Evaluation on the diagnostic value of body mass index in predicting diabetes in the first-degree relatives of type 2 diabetic patients

目的肥胖与2型糖尿病的发生、发展密切相关,体质指数(body mass index,BMI)是世界公认的一种评定肥胖程度的分级方法,本文探讨BMI与高血糖的关系及其在2型糖尿病一级亲属中进行糖尿病筛查的预测价值。方法选取2003年1—6月期间住院以及门诊确诊的2型糖尿病患者的一级亲属296例为研究对象,所有受试者均测量身高、体重,计算BMI,并行75 g口服葡萄糖耐量试验(OGTT),采用葡萄糖氧化酶法测定空腹血糖、餐后30、60及120 min血糖。采用梯形规则计算血糖曲线下面积。用接收者工作特征曲线分析评价BMI水平在糖尿病筛查中的价值。结果 (1)2型糖尿病一级亲属糖调节异常及糖尿病患病率分别为30.07%和19.93%。从正常糖耐量经糖调节异常到糖尿病状态,BMI进行性增加(P<0.001)。(2)对糖耐量正常组分别以OGTT血糖下面积(area under the blood glucose curve,AUCg)为因变量,以年龄、BMI为自变量进行线性逐步回归分析显示,年龄、BMI是影响AUCg的独立因素(P=0.027、0.015)。(3)ROC分析提示,BMI≥24.95 kg/m^2出现糖调节异常的可能性大,灵敏度为67.3%,特异度为62.2%。结论 2型糖尿病具有明显家族聚集性,BMI为2型糖尿病一级亲属高血糖重要的预测因子,建议以BMI≥24.95 kg/m^2为切点对2型糖尿病一级亲属进行筛查。

Objective Obesity is closely related to the occurrence and development of type 2 diabetes mellitus. Body mass index （BMI） is a worldly recognized classification method for assessing the degree of obesity. To investigate the relationship between body mass index（BMI） and hyperglycemia and evaluate the diagnostic value of BMI in predicting diabetes in the first-degree relatives of type 2 diabetic patients. Methods We conducted a prospective cohort study in a sample of 296 first-degree relatives without glucose intolerance history. All adults were examined on height, weight, calculated BMI and underwent an oral glucose test（OGTF）. Their level of fasting blood glucose,30-minute postprandial plasma glucose, 60-minute postprandial plasma glucose, 120-minute postprandial plasma glucose were determined by the glucose oxidase- peroxidase method. The area under the blood glucose curve（AUCg） was calculated by the trapezoidal rule. Evaluation of the value of BMI levels in diabetes screening by receiver operating characteristic curve analysis （ROC）. Results （1）The prevalence rates of impaired glucose regulation and diabetes were 30.07% and 19.93% in the first-degree relatives of type 2 diabetic patients respectively. From normal glucose tolerance condition through impaired glucose regnlation to diabetic, the BMI progressively increased（ P 〈 0. 001 ）. （2）Area under the curve sugar of OGTT（AUCg） as dependent variable, age and BM1 as the independent variable in normal glucose tolerance group,linear stepwise regression analysis showed that age and BMI were the independent factors（ P = 0. 015 ）. （3）The optimal cutoff value of sensitivity and specificity of BMI were 24.95 kg/m^2 ,67.3 % and 62.2% by receiver operating characteristic （ROC） curve. Conclusion BMI is a strong predictor for hyperglycemia in the first-degree relatives of type 2 diabetic patients. It is therefore suggested that BMI≥24.95 kg/m^2 be recommended as diagnostic cut-off points in the first-degree relatives of type 2 diabetic patients.