Barakat H A, Mooney N, O'Brien K, Long S, Khazani P G, Pories W, Caro J F
Department of Biochemistry, School of Medicine, East Carolina University, Greenville, North Carolina 27858-4354.
Diabetes Care. 1993 Jan;16(1):144-9. doi: 10.2337/diacare.16.1.144.
OBJECTIVE--To examine if the risk for CHD increases progressively with increases in the BMI of normoglycemic, hyperinsulinemic, morbidly obese women (BMI > or = 35 kg/m2). RESEARCH DESIGN AND METHODS--Insulin sensitivity was evaluated by calculating an ISI following an OGTT. There was a significant linear relationship between ISI and BMI fitted by two straight lines intersecting at a point corresponding to a BMI of 29.7 +/- 1.5 kg/m2. Significant linear relationships between insulin sensitivity and BMI were obtained below and above this breakpoint. Similarly, a breakpoint for the relation between dBP and BMI corresponding to a BMI > or = 33.7 +/- 3.4 kg/m2 was obtained. Significant linear relationships between BMI and plasma fasting glucose, triglyceride, cholesterol, HDL cholesterol, sBP, or dBP were not observed in the women with a BMI > 35 kg/m2. RESULTS--Compared with lean (BMI < 27) women of similar age, the morbidly obese patients appear to be at a higher risk for CHD. This is suggested by statistically significant increases in fasting insulin (mean +/- SD; 187 +/- 137 vs. 64.2 +/- 16.2 pM) and triglyceride levels (128 +/- 78.1 vs. 73 +/- 25 mg/dl), sBP (132 +/- 114 vs. 104 +/- 15.8) and dBP (84 +/- 72 vs. 67 +/- 2.1 mmHg), and decreases in HDL cholesterol (1.03 +/- 0.44 vs. 1.29 +/- 0.82 mM) and apo A-I (91 +/- 55 vs. 122 +/- 35 mg/dl) concentrations. CONCLUSIONS--It appears that there may be a threshold of body mass up to which insulin sensitivity is associated with CHD risk. Above this threshold, there does not appear to be a progressive increase in the risk factors for CHD with increases in BMI.
目的——研究血糖正常、高胰岛素血症的病态肥胖女性（体重指数[BMI]≥35kg/m²）的冠心病风险是否随BMI升高而逐渐增加。研究设计与方法——通过口服葡萄糖耐量试验（OGTT）计算胰岛素敏感指数（ISI）来评估胰岛素敏感性。ISI与BMI之间存在显著的线性关系，由两条直线拟合，在BMI为29.7±1.5kg/m²处相交。在该断点之下和之上，胰岛素敏感性与BMI之间均获得了显著的线性关系。同样，获得了舒张压（dBP）与BMI关系的一个断点，对应BMI≥33.7±3.4kg/m²。在BMI＞35kg/m²的女性中，未观察到BMI与空腹血糖、甘油三酯、胆固醇、高密度脂蛋白胆固醇（HDL胆固醇）、收缩压（sBP）或dBP之间存在显著的线性关系。结果——与年龄相仿的瘦女性（BMI＜27）相比，病态肥胖患者似乎患冠心病的风险更高。空腹胰岛素（均值±标准差；187±137对64.2±16.2pM）、甘油三酯水平（128±78.1对73±25mg/dl）、sBP（132±114对104±15.8）和dBP（84±72对67±2.1mmHg）有统计学显著升高，HDL胆固醇（1.03±0.44对1.29±0.82mM）和载脂蛋白A-I（91±55对122±35mg/dl）浓度降低，提示了这一点。结论——似乎存在一个体重阈值，在该阈值以下胰岛素敏感性与冠心病风险相关。高于此阈值，冠心病危险因素似乎不会随BMI升高而逐渐增加。
