BMI,Waist Circumference and All-Cause Mortality in a Middle-Aged and Elderly Chinese Population

Objective

To investigate the association of obesity and all-cause mortality in a sample of middle-aged and elderly population.

Design and Setting

Information of participants was collected in the Dongfeng-Tongji study, a perspective cohort study of Chinese occupational population. The main outcome was risk of death after 8.5 years of follow-up.

Participants and measurements

We examined the association of BMI, waist circumference (WC, and waist–height ratio (WHtR) with all-cause mortality in the Dongfeng-Tongji cohort study (n=26,143). Cox proportional hazard models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CI) for all-cause mortality. Area under the receiver operating characteristic curves and net reclassification improvement (NRI) were used to calculate the power of prediction models.

Results

During a mean of 8.5 years of follow-up, 2,246 deaths were identified. There is a U-shaped association of BMI with all-cause mortality in the middle-aged and elderly Chinese population. Compared with individuals with normal BMI, underweight was positively (HR=2.16, 95% CI: 1.73, 2.69) while overweight (HR=0.75, 95% CI: 0.67, 0.84) and obesity (HR=0.67, 95% CI: 0.56, 0.79) were negatively associated with all-cause mortality after adjustment for potential confounders including WC. In contrast, WC (Q5 vs. Q1, HR=1.55, 95% CI: 1.29, 1.86) and WHtR (Q5 vs.Q1, HR=1.69, 95% CI: 1.40, 2.04) were positively associated with mortality after further adjustment for BMI (P trend < 0.001). Addition of both BMI and WC into the all-cause mortality predictive model significantly increased AUC (P =0.0002) and NRI (NRI = 2.57%, P = 0.0007).

Conclusions

BMI and WC/WHtR were independently associated with all-cause mortality after mutual adjustment. Combination of BMI and WC/WHtR improved the predictive ability of all-cause mortality risk in the middle-aged and elderly population.

     

Neck and Waist Circumference Biomarkers of Cardiovascular Risk in a Cohort of Predominantly African-American College Students: A Preliminary Study

Receiver operating characteristic curves were constructed to assess the value of measuring neck and waist circumference and waist-to-hip ratio (WHR) as biomarkers of metabolic syndrome in college students (18 to 25 years of age). Participants (n=109) were 92% black, 62.4% female, 45.9% overweight or obese, and 20.2% prehypertensive or hypertensive. Overall, 41 (37.6%) students had one or more risk factors for metabolic syndrome. Percent body fat, assessed using whole-body air-displacement plethysmography, was positively correlated (P<0.0001) with neck and waist circumference (as measured at the midpoint between the right lower rib and suprailiac crest; hereafter “midpoint”). Neck circumference correlated with low-density lipoprotein cholesterol (P≤0.02) and both neck circumference and waist circumference-midpoint correlated with insulin (P≤0.001) and triglycerides (P≤0.002). The best-fit cutoffs were ≥83 cm waist circumference-midpoint and ≥88 cm waist circumference measured at the suprailiac crest for percent body fat in men and ≥75 cm waist circumference-midpoint for metabolic syndrome in women. The proportion of overweight and prehypertensive individuals among self-described healthy students underscores the need for screening tools that identify those who might benefit most from health interventions. Waist circumference-midpoint provides a simple yet sensitive method for the estimation of percent body fat and metabolic syndrome risk in primarily African-American college students. The novel use of neck circumference should be further investigated.     

北纬53°地区人群体质指数、腰臀比与高血压关系的调查

目的：解高寒地区人群超重肥胖、中心性肥胖发生率及其与高血压的关系。以期为肥胖和高血压的防治措施制定提供研究依据。方法对北极村1064例体检者进行身高、体重、腰围、臀围、血压等检测,并按照腰臀比值、体质指数进行分层分析各组与高血压相关性。结果受检者肥胖患病率为19.55%,超重的患病率为35.81%,中心性肥胖患病率为69.64%,高血压患病率为27.16%。正常人群随着BMI的增加,高血压的患病率呈明显上升趋势;中心性肥胖人群随着BMI的增加高血压的患病率显著上升(P<0.0001)。将WHR和BMI作为自变量对高血压的患病率进行相关性分析,结果显示,肥胖组和超重组高血压的患病率明显高于正常体重组(P<0.0001);中心性肥胖组的高血压率明显高于正常体型组(P<0.0001)。经多因素相关分析,WHR和BMI与高血压都有极显著性意义(P<0.0001)。结论该研究结果显示,超重,肥胖和中心性肥胖都是高血压的独立危险因素。即使BMI仍在标准范围的人,若是任由腰围一直变大,对健康而言,仍是一种非常不良的信号。因此,如果只注意体重,而忽视腹部脂肪过多,仍有发生慢性疾病的危险。     

Peer Reviewed: Identifying Adolescent Metabolic Syndrome Using Body Mass Index and Waist Circumference

Introduction

Metabolic syndrome is increasing among adolescents. We examined the utility of body mass index (BMI) and waist circumference to identify metabolic syndrome in adolescent girls.

Methods

We conducted a cross-sectional analysis of 185 predominantly African American girls who were a median age of 14 years. Participants were designated as having metabolic syndrome if they met criteria for 3 of 5 variables: 1) high blood pressure, 2) low high-density lipoprotein cholesterol level, 3) high fasting blood glucose level, 4) high waist circumference, and 5) high triglyceride level. We predicted the likelihood of the presence of metabolic syndrome by using previously established cutpoints of BMI and waist circumference. We used stepwise regression analysis to determine whether anthropometric measurements significantly predicted metabolic syndrome.

Results

Of total participants, 18% met the criteria for metabolic syndrome. BMI for 118 (64%) participants was above the cutpoint. Of these participants, 25% met the criteria for metabolic syndrome, whereas only 4% of participants with a BMI below the cutpoint met the criteria for metabolic syndrome (P <.001). Girls with a BMI above the cutpoint were more likely than girls with a BMI below the cutpoint to have metabolic syndrome (P = .002). The waist circumference for 104 (56%) participants was above the cutpoint. Of these participants, 28% met the criteria for metabolic syndrome, whereas only 1% of participants with a waist circumference below the cutpoint met the criteria for metabolic syndrome (P <.001). Girls with a waist circumference above the cutpoint were more likely than girls with a waist circumference below the cutpoint to have metabolic syndrome (P = .002). Stepwise regression showed that only waist circumference significantly predicted metabolic syndrome.

Conclusion

Both anthropometric measures were useful screening tools to identify metabolic syndrome. Waist circumference was a better predictor of metabolic syndrome than was BMI in our study sample of predominantly African American female adolescents living in an urban area.     

Waist Circumference Trajectories in Relation to Blood Pressure and the Risk of Hypertension in Chinese Adults

Central obesity is associated with a higher risk of hypertension. This study aimed to analyze waist circumference (WC) trajectories and discover their association with blood pressure and the risk of hypertension. The data were obtained from the China Health and Nutrition Survey (CHNS), with a sample of 11,885 adults aged 18 or older. Trajectory groups of WC were identified by group-based trajectory modeling. Three trajectory groups were identified in males: “normal-stable group” (group 1), “normal-increase to central obesity group” (group 2), and “central obesity-slight decrease group” (group 3). There were also three identified in females: “normal-increase to central obesity group” (group 1), “normal-stable group” (group 2), and “central obesity-increase group” (group 3). For males, compared with group 1, systolic blood pressure (SBP) and diastolic blood pressure (DBP) increased by 2.47 mmHg and 2.13 mmHg, respectively, in group 2, and by 3.07 mmHg and 2.54 mmHg, respectively, in group 3. The adjusted hazard ratios (HR) and 95% confidence interval (95% CI) of hypertension in groups 2 and 3 were 1.16 (1.06–1.28) and 1.29 (1.10–1.50), respectively. For females, compared with group 2, SBP and DBP increased by 1.69 mmHg and 1.68 mmHg, respectively, in group 1, and by 4.96 mmHg and 2.77 mmHg, respectively, in group 3. The HR and 95% CI of hypertension in groups 2 and 3 were 1.21 (1.07–1.36) and 1.52(1.17–1.99), respectively. We found that the WC trajectory was a risk factor for hypertension and elevated blood pressure independent of basal WC. Increased risk of hypertension was nonlinearly associated with annual WC increase.     

上海市35-74岁成人代谢综合征腰围切点的研究

［目的］ 探寻上海市35-74 岁人群中代谢综合征（metabolic syndrome,MS）相关肥胖程度的腰围切点。 ［方法］采用多阶段随机抽样方法,在上海市35~74 岁居民中进行横断面调查,共调查7 414 名个体。分析男性和女性不同腰围水平与MS 其他因素的关系,以获得检出2 个及以上危险因素敏感性和特异性均较好的腰围切点。 ［结果］ 随腰围增大,MS 危险因素聚集的比值比（OR）也随之升高,检出2 个及以上MS 危险因素的特异度和阳性预测值逐渐增高,而敏感度和阴性预测值逐渐下降。当男性腰围≥ 85 cm、女性腰围≥ 80 cm,检出2 个及以上MS 危险因素的敏感度为68.33%（男性）、70.17%（女性）,特异度为58.48%（男性）、58.36%（女性）,受试者工作特征曲线（ROC）距离最短,分别为男性0.522 1、女性0.512 2。 ［结论］ 当男性腰围≥ 85 cm、女性腰围≥ 80 cm时,能较好反映MS 危险因素的聚集,为本研究人群代谢综合征肥胖的腰围切点。     

高血压家系中高血压与血糖、血脂、体质指数和腰围关系的研究

目的探讨在高血压家系中聚集的高血压危险因素。方法2003--2004年，在江苏常州地区5个社区中，收集高血压家系104个，含直系血亲523人，其中男性278人，女性245人；旁系（配偶）265人，其中男性81人，女性184人。检测其空腹血糖（FPG）、血脂、尿酸（UA）、体质指数（BMU及腰围，应用SPSS11．5软件包进行统计分析。结果调整年龄、性别后，3组间两两比较发现，直系高血压组UA、FPG、甘油三酯（TG）、BMI和腰围均高于直系正常血压组，高密度脂蛋白胆固醇（HDL-C）低于直系正常血压组，差别均有统计学意义（P〈0．01）；直系高血压组UA、FPG、TG、TC、BMI和腰围均高于旁系正常血压组，HDL—C低于旁系正常血压组，差别均有统计学意义（P〈0．01）；直系正常血压组TC、腰围高于旁系正常血压组，UA低于旁系正常血压组，差别有统计学意义（P〈0．05）。Logistic回归分析显示，在家族直系成员中，高血压发病与文化程度、吸烟、性格、BMI和FPG有关。结论在高血压家系中，其高血压病危险因素存在着一定的家族聚集现象。     

中国汉族学龄儿童青少年腰围正常值

目的了解中国学龄儿童腰围正常值,为建立中国学龄儿童青少年超重/肥胖筛查标准提供依据。方法以2008年全国学生体质健康监测15省市区14.6万余名7～18岁汉族中小学生为参照人群,以LMS法建立腰围正常值。结果获得中国7～18岁汉族中小学生各年龄组男女腰围P3,P5,P10,P15,P25,P50,P75,P85,P90,P95和P97百分位数正常值及其LMS曲线。结论利用腰围正常值可在经疾病危险因素验证后建立腰围筛查超重、肥胖界值点的标准,并就验证过程一些必要的步骤和方法提出建议。     

Dietary Predictors of 5-Year Changes in Waist Circumference

Background

Previous studies on the association between macronutrient intake and the development of abdominal obesity, which carries an increased health risk, have not shown a consistent pattern, possibly due to mixed effects of other aspects of the food intake.

Objective

This study investigated the association between intake from 21 food and beverage groups and the subsequent 5-year difference in waist circumference.

Methods

The study population consisted of 22,570 women and 20,126 men, aged 50 to 64 years at baseline, with complete data on baseline and follow-up waist circumference, baseline diet (192 items food frequency questionnaire), body mass index, and selected potential confounders (eg, smoking status, sport activities, and intake of alcoholic beverages). Multiple linear regression analyses were performed.

Results

For women, 5-year difference in waist circumference was inversely related to intake from red meat, vegetables, fruit, butter, and high-fat dairy products, whereas intake from potatoes, processed meat, poultry, and snack foods was positively associated. For men, red meat and fruit intakes were inversely associated with 5-year difference in waist circumference, whereas snack foods intake was positively associated. Sex differences occurred for vegetables, high-fat dairy products, and processed meat.

Conclusions

The results suggest that a diet low in fruits and red meat and high in snack foods was associated with larger waist circumference gains in both sexes. Furthermore, in women a diet low in vegetables, butter, and high-fat dairy products, and high in poultry, potatoes, and processed meat were likely determinants of subsequent gain at the waist.     

Cardiovascular Risk Factors in Italy

In the 1950s the Italian population was known for its low mean levels of major cardiovascular risk factors and serum cholesterol in particular. A definite increase of those mean levels was associated, in the next 2 decades, with increasing death rates from cardiovascular diseases and coronary heart disease. Between the late 1970s and early 1990s cardiovascular death rates declined by over 40%. Large population surveys showed, between 1978 and 1987, small decreases in the mean levels of blood pressure (in both sexes), of smoking habits (in men), and of body weight (in women), while serum cholesterol remained stable. These changes mathematically explained about two-thirds of the observed decline in cardiovascular mortality among middle-aged people. In the late 1980s and early 1990s scattered population studies suggested a decline in mean population levels of serum cholesterol, at least in some areas of the country. More coordinated or systematic preventive campaigns were organized by the public health authorities. On the other hand activities of many small private organizations dealing with heart health likely explain the spread of knowledge, attitude, and practice in the prevention of cardiovascular diseases. Food industry started to produce low-fat products and to label foods with nutrition facts. Changes in food consumption in the beneficial direction started to be recorded in the late 1980s. The spread of anti-hypertensive treatment was partly favored by the National Health Service offering anti-hypertensive drugs at relatively low cost. Government regulations have more and more restricted the public areas where smoking is allowed. An increasing interest for prevention on the part of physicians is a recent issue, mainly bound to the success of some major controlled trials of hypocholesterolemic drugs.     

Association of Food Parenting Practices on Child BMI z Score and Waist Circumference in Mexican Preschool Children After 1 Year of Follow-Up

ObjectiveTo evaluate the association between food parenting practices (FPPs) and weight status among preschoolers and the directionality of this association at 1-year follow-up.MethodsA longitudinal exploratory study was conducted using linear regression and structural equation modeling to determine directional associations between FPPs and children's body mass index z score and waist circumference. The FPPs were estimated using Child Feeding Questionnaire subscales.ResultsA total of 91 parent–child dyads completed the study. In structural equation modeling analysis, when identifying the FPPs in a latent variable with its indicators of indulgent feeding, food as a reward and restriction predicted higher body mass index z score at follow-up. Higher baseline waist circumference was also negatively associated with the use of food as a reward.Conclusions and ImplicationsFeeding–weight associations are likely bidirectional. Understanding them, as well as the pathways between them, is critical to developing effective prevention and treatment strategies.     

Cardiovascular Diseases and Risk Factors in Finland

We summarize here the evidence from the 1960s and 1970s of exceptionally high risk of cardiovascular disease (CVD) in Finland. In parallel with voluntary and governmental prevention programs, the level of risk factors and CVD attack rates have shown dramatic improvement in the past 25 years, but the decline has slowed in recent years. This experience strongly supports population-wide strategies for primary prevention, and it also highlights the continued need for primordial prevention directed toward youth in high-risk societies.     

Physical Activity,Weight, and Waist Circumference in Midlife Women

During midlife years, women are at risk of increasing body weight and waist circumference. We evaluated changes in weight and waist circumference from enrollment to 2 years later and examined the influence of physical activity level on those changes among 232 women aged between 40 and 50. Weight increased significantly for the entire sample. Those who increased their physical activity from enrollment to 2 years later had the smallest increase in weight and had a slight decrease in waist circumference. To maintain ideal weight and waist circumference, midlife women should be encouraged to increase physical activity before and during the menopausal transition.     

辽宁地区居民体重指数、腰围与血压关系的研究

目的探讨辽宁地区居民体重指数、腰围与血压值、高血压患病率的关系。方法按照多阶段整群随机抽样方法,对辽宁地区15岁及以上居民的血压、身高、体重、腰围等指标进行流行病学统计分析。结果体重指数(kg/m2)<18.5,18.5~23.9,24~27.9,≥28,血压均值分别为116.4/73.9mmHg、122.0/76.5mmHg、130.5/81.4mmHg、138.4/85.9mmHg,高血压患病率分别为13.6%、20.4%、35.2%和53.9%;腰围从正常到腹部肥胖,血压均值从121.7/76.6mmHg上升到133.6/82.9mmHg,高血压患病率从19.8%上升到42.8%。当体重指数≥24(kg/m2)或腰围进入腹部肥胖时,血压值、高血压患病率明显增加。经多元线性回归分析,血压值与体重指数和腰围呈正相关,而且腰围对血压均值的影响大于体重指数对血压的影响;Logistic回归分析显示,超重、肥胖和腹部肥胖与正常组相比发生高血压的相对危险性增加1.5、2.6和2.0倍。结论超重和肥胖是高血压的两个危险因素,保持理想的体重和腰围对控制高血压的发生起着决定性作用。