【作者】 吴红艳；

【导师】 陈璐璐；

【作者基本信息】 华中科技大学 ， 内科学， 2007， 博士

【摘要】 背景:腰围(waist circumference, WC)是简单和实用的反映中心性肥胖的有效工具,也是国际糖尿病联盟(International Diabetes Federation,IDF)关于代谢综合征(metabolic syndrome, MS)定义的必要条件之一。然而目前世界范围内(包括中国)尚缺乏统一的WC测量方法。常用的测量部位包括如下4个,上腰围(WC1):通过身体两侧面肋弓下缘最低点的水平周径;自然腰围(WC2):即腰部最细的部位;中腰围(WC3):肋弓下缘最低点和髂嵴之间中点的水平周径;下腰围(WC4):通过髂嵴最高点或脐平面的水平周径。目的:比较中国成人4个部位腰围测量值的大小,分析各部位腰围测量的最佳切点,并确定评价MS的首要组分——中心性肥胖的最佳测量部位。方法:入选1021名男性及938名女性,均测定4个部位腰围及血压、血脂、血糖等危险因子。MS的定义:基于2005年IDF的标准,腰围达到某个切点以上,加上同时具有下述4项因素中的2项即可检出为MS。①TG≥1.7mmol/L或者既往曾经诊断为高TG血症接受相关治疗者;②HDL-C≤0.9 mmol/L(男性)/l.1 mmol/L(女性)或既往曾经诊断为低HDL-C血症接受相关治疗者;③收缩压(SBP)≥130mmHg和/或舒张压(DBP)≥85mmHg,或以往诊断为高血压接受相关治疗者;④空腹血糖(FBG)≥5.6 mmol/L或以往曾经诊断为2型糖尿病者。以重复测量的方差分析比较4个部位腰围值的差异,以受试者工作特征(ROC)曲线下面积比较不同测量部位的腰围对代谢综合征的诊断效能。结果:两性中腰围大小顺序均为:WC2 < WC1 < WC3 < WC4。ROC分析显示:对于≥2个危险因素,男性以WC1的曲线下面积最大,女性则以WC2面积最大。≥2个危险因素的腰围切点分别为:男性,WC1 = 84.3 cm, WC2 = 84.8 cm, WC3 = 85.8 cm,WC4 = 87.3 cm;女性,WC1 = 76.8 cm, WC2 =76.8 cm, WC3 = 77.3 cm and WC4 = 84.5 cm。结论:中国成人不同部位腰围测量值存在明显差异,腰围测量部位不同,诊断代谢综合征的切点值亦不同。男性最佳测量部位为上腰围,女性为最细部位。下腰围预测效能相对较差。目的目前使用的反映肥胖的指标有体重指数(BMI)、腰围(WC)、腰臀围比值(WHR)等多种,本研究旨在探讨腰围/身高比值(WHtR)用于评价2型糖尿病患者腹型肥胖的可行性,并评价究竟哪一个肥胖指标能更好地预测心血管病危险因素。方法411例新确诊的2型糖尿病患者,测量血压、身高、体重、WC、臀围,计算BMI、WHtR及WHR,并检测血糖、血脂等。采用Pearson相关系数分析WHtR、BMI、WC及WHR与身高的关系并评价各指标间及其与血压、血脂的相关性,采用多元线性回归分析各肥胖指数与身高的关系。用logistic回归分析各肥胖指数预测高血压、高TG血症、低HDL-C风险的比值比。患病率比较用X2检验。受试者工作特征(Receiver Operator Characteristic,ROC)曲线分析各肥胖指数预测危险因素的效能。结果(1)WHtR在2型糖尿病患者中的分布特征无明显性别差异。(2)X2检验显示WHtR与高血压、高甘油三酯(TG)血症及低高密度脂蛋白胆固醇(HDL-C)血症的关联最大,其次为WC。WHtR水平升高与高血压、高TG血症及低HDL-C血症均显著相关。(3)logistic回归分析显示,调整混杂因素后,WHtR增高预测高血压、高TG血症、低HDL-C风险的比值比最高,OR分别为男性:2.56 (95%CI: 1.24, 5.29), 2.87 (95%CI: 1.43, 5.78), 2.59 (95%CI: 1.03, 6.59);女性:3.75 (95%CI: 1.75, 8.05),3.21 (95%CI: 1.52, 6.79),3.62 (95%CI: 1.43, 9.21)。(4)各肥胖指数对应于≥1个危险因素的最佳切点,男女分别为:BMI,24.5和24.9 kg/m2;WC 83和81 cm;WHR, 0.89和0.86;WHtR,0.51和0.50。男女性均以WHtR的曲线下面积最大。结论与WC,WHR及BMI相比,WHtR水平升高与初诊2型糖尿病患者血压、血脂异常关系更为密切,可作为有效的腹型肥胖参考指标及2型糖尿病心血管疾病危险因素预测指标之一。保持正常的腰围/身高比值十分重要,通过对腰围和身高的测量我们可以初步评价2型糖尿病发生冠心病的风险是否增加。我们应重视对腰围和身高的同步测量,应作为临床筛查糖尿病大血管病变的基本手段之一。目的探讨简易体脂参数与精确体脂参数——腹壁皮下(SA)及腹腔内脂肪含量(VA)的关系,并且比较各简易体脂参数与腹部脂肪的相关性大小,为筛选高危人群时选择最佳简易体脂参数提供理论依据。方法应用计算机断层扫描(CT)对111例男性志愿受试者在腰椎4、5间隙水平进行SA及VA的测量,同时测量其体重、身高、腰围(WC)、臀围,计算体重指数(BMI)、腰臀比(WHR)以及腰围/身高比值(WHtR)。精确体脂参数与简易体脂参数的关系采用单因素分析。由于这些肥胖指数高度相关,将他们进行多因素回归分析存在共线性问题,因此,采用Andel的t-检验比较这些非嵌套模型相关系数的大小。结果VA和SA均与BMI、WC、WHR、WHtR呈显著正相关,但与WHtR的相关性最好。WHtR与VA的关联强于WC (p=0.012), BMI(p<0.001)或WHR(p<0.001)。WHtR与SA的关联明显强于BMI(p=0.02)和WHR(p<0.001),稍强于WC,但差异无统计学意义(p > 0.05)。结论所选用的四个简易体脂参数都可用于估测腹部脂肪分布,但以WHtR判断的准确率稍高。我们建议以此参数对患者进行肥胖的评估,从而更好的评估其相应的代谢性疾病的危险性。更多还原

【Abstract】 Objective:The diagnosis of metabolic syndrome was defined as central obesity plus two or more of the following factors: elevated plasma triacylglycerol, blood pressure, fasting plasma glucose and reduced HDL cholesterol. Central obesity was defined according to the values of waist circumference (WC). However there is no universally accepted standard for measuring WC. Four body sites are commonly used: immediately below the lowest ribs (WC1), the narrowest waist (WC2), the midpoint between the lowest rib and the iliac crest (WC3), and immediately above the iliac crest (WC4). We sought to compare the magnitude of WC measured at these 4 sites and to optimize WC site for defining central obesity.Design:WC measures were taken at the 4 sites and blood pressure, fasting plasma glucose and lipids were determined in 1021 men and 938 women, aged 20–81y。Metabolic risk factors were defined according to the IDF criteria: TG≥1.7 mmol/L or specific treatment of this lipid abnormality; HDL-C≤1.03 mmol/L for men and≤1.29 mmol/L for women or specific treatment of this lipid abnormality; SBP≥130 mmHg, DBP≥85 mmHg, or treatment for previously diagnosed hypertension; FPG≥5.6 mmol/L or previously diagnosed type 2 diabetes. Participants were classified as having IDF metabolic syndrome if they had central obesity and two or more of the above four risk factors. In the present analysis, central obesity was omitted as a component of the metabolic syndrome in the prediction from WC cut-offs. Repeated-measures analysis of variance and Receiver Operator Characteristic (ROC) curves were used in analysis.Results:The comparisons among the 4 WC measures showed that WC values at the 4 sites differ in magnitude from each other regardless of sex, with WC2 < WC1 < WC3 < WC4. In ROC analysis, the areas under curve (AUC) of WC1 in men and the AUC of WC2 in women were the largest for≥2 risk factors. The cutoff values in men ranged from 83.3 to 84.8 for WC1, 84.3 to 85.3 for WC2, 84.8 to 85.8 for WC3 and 85.3 to 87.3 for WC4; and in women from 75.8 to 77.3 for WC1, 75.8 to 76.8 for WC2, 77.3 to 78.3 for WC3 and 84.5 to 85.3 for WC4. As an overall estimation, the cutoff values for two or more risk factors in men were WC1 = 84.3, WC2 = 84.8, WC3 = 85.8 and WC4 = 87.3; and in women WC1 = 76.8, WC2 =76.8, WC3 = 77.3 and WC4 =84.5.Conclusions:Both the WC values and the cutoffs for metabolic syndrome vary across measure sites in Chinese population. In addition, the measurement site for WC has a substantial influence on the strength of association with metabolic syndrome, especially for women. We advocate the measures below the lowest rib for men and the narrowest waist for women. The site immediately above the iliac crest was not recommended in Chinese population. Objective: To assess the relationship of waist circumference (WC) and waist to height ratio (WHtR) with height, and to validate WHtR as predictors for the presence of cardiovascular disease risk factors in Type 2 diabetic patients.Objective: To determine which is the best anthropometric index among body mass index (BMI), waist circumference (WC), waist to hip ratio (WHR) and waist to height ratio (WHtR) in relation to cardiovascular risk factors in Chinese Type 2 diabetic patients.Method: 411 patients (198 men and 213 women) with newly diagnosed Type 2 diabetes, not currently affected by macrovascular complications were evaluated. height, weight, waist and hip circumference, waist/hip ratio(WHR)and WHtR were measured. HbA1c,Bp and plasma lipid profile were detected. Partial correlation, chi-square test, logistic regression analysis and Receiver Operator Characteristic (ROC) curves were used in analysis.Results: WHtR had the highest r Among all the cardiovascular risk factors in both sexes in partial correlation analysis,followed by WC. Chi-square analysis revealed that an increased WHtR was more strongly associated with hypertension, hypertriglyceridemia (high TG) and low high-density lipoprotein cholesterol (HDL-C) than the other indices. Logistic regression analysis showed that, after controlling for age, the hypertension, high TG and low HDL-C odds ratios of WHtR≥0.5 were 2.56 (95%CI: 1.24, 5.29), 2.87 (95%CI: 1.43, 5.78), 2.59 (95%CI: 1.03, 6.59) in men and 3.75 (95%CI: 1.75, 8.05),3.21 (95%CI: 1.52, 6.79),3.62 (95%CI: 1.43, 9.21) in women, respectively. In ROC analysis, the areas under curve of WHtR were the largest relative to at least one risk factor in both men and women.Conclusions: WHtR shows stronger correlation than WC , WHR or BMI with cardiovascular risk factors in newly diagnosed Type 2 diabetes. We propose the measurement of WHtR as a screening tool for cardiovascular risk factors in this population. WHtR measurement can provide an opportunity for primary prevention of coronary heart disease in patients with newly diagnosed Type 2 diabetes. Background: The accumulation of fat in visceral (VA) and subcutaneous abdominal adipose tissue (SA) is highly correlated with the metabolic abnormalities that contribute to increased risk of diabetes mellitus and cardiovascular disease.Aim: To determine which of waist circumference (WC), waist-to-hip ratio (WHR), waist to height ratio (WHtR) and body mass index (BMI) was the best predictor of VA and SA in men.Methods: We studied 111 free-living men with a wide range of BMI. WC, WHtR, WHR and BMI were determined using standard methods. SA and VA were quantified using computed tomography.Results: In univariate regression analysis, WC, WHtR WHR and BMI were all significantly and positively correlated with VA and SA (all p < 0.05), the highest correlation being seen for WHtR, the lowest for WHR. To assess the relative strength of these associations, we used non-nested regression models. WHtR was a stronger predictor of SA than BMI(p=0.02), but the relative strength of WC and BMI in predicting SA did not different significantly (p > 0.05). WHtR was a stronger predictor of VA than WC (p=0.012), BMI(p<0.001) or WHR(p<0.001).Conclusions: In men WHtR is a good anthropometric index that most uniformly predicts the distribution of visceral and subcutaneous abdominal adipose tissue. Its predicting power is closer to or better than WC. There apparently being little value in measuring WHR or BMI.更多还原