肥胖、腹腔内脂肪与骨矿密度、骨强度的关系

最近已提出骨强度指标可避免用骨矿密度 (BMD)诊断骨质疏松 (OP)的误诊与漏诊 ,且发现校正骨矿含量 (c BMC)与骨强度的相关性很好。我们以 c BMC作为骨强度的替代指标 ,并与 BMD进行对比 ,以评价 BMD用于诊断肥胖者 OP是否具有局限性。从社区中选 10 2名体重指数 (BMI) 2 5～ 39kg/m2 健康者为研究对象 ,其中男性 31例 ,女性 71例 ,平均年龄 37.2± 9.4岁。采用美国 L unar公司生产的 DEXA仪测量下肢、躯干、全身 BMD及BMC。c BMC用 BMC÷体重表示 ,用 CT测量 L4- 5椎间平面腹腔内脂肪面积。统计方法用 SPSS10 .0软件作直线相关分析。结果显示 ,体重、BMI与下肢、躯干、全身 BMD呈正相关或正相关趋势 ,与 c BMC呈负相关或负相关趋势。腹内脂肪面积与下肢、躯干、全身 BMD呈负相关或负相关趋势 ,与 c BMC呈负相关。有报道肥胖者的 BMD虽增加但骨强度反而降低 ,本研究也说明用 BMD诊断肥胖者的 OP会导致漏诊 ,而 c BMC与骨强度指标变化趋势一致 ,在一定程度上可代替骨强度指标用于诊断肥胖者 OP。

The Relationship between Obesity, Intra Abdominal Fat Area and Bone Mineral Density and Bone Strength

Recently some studies have showed that bone strength may avoid the misdiagnosis and missed diagnosis of osteoporosis(OP) by bone mineral density (BMD) alone. It was found that corrected bone mineral content (cBMC) was well correlated with bone strength. In this study bone strength was replaced by cBMC to compare it with BMD, and evaluate whether BMD has limitations in the diagnosis of OP in obese individuals. one hundred and two healthy subjects in the community with the body mass index (BMI) between 25 and 39 kg/m2 were enrolled. There were 31 males and 71 females with a mean age of 37.2 +/- 9.4 years. Their BMD and BMC of lower limbs, trunk and the whole body were measured with dual energy X-ray absorptiometry (DEXA). cBMC was expressed by BMC divided by weight. Intra abdominal fat area (IAFA) was measured by CT scan at the level between 4th-5th lumbar vertebra. Linear correlation analysis with SPSS 10.0 soft pack was used for statistics. The results showed that there was a positive correlation and tendency between body weight, BMI and BMD values of lower limbs, trunk and the whole body. However, negative correlation and tendency were demonstrated between body weight, BMI and cBMC, between IAFA and BMD of lower limbs, trunk and the whole body and between IAFA and cBMC as well. We found that the tendency of changes of cBMC and bone strength was similar. So we suggest in certain extent that cBMC could replace bone strength in the diagnosis of OP in obese individuals.