Waist circumference and obesity-associated risk factors among whites in the third National Health and Nutrition Examination Survey: clinical action thresholds

BACKGROUND: Waist circumference (WC) is strongly linked to obesity-associated risks. However, currently proposed WC risk thresholds are not based on associations with obesity-related risk factors but rather with body mass index (BMI; in kg/m(2)). OBJECTIVE: The objective was to determine the relations of WC to obesity-associated risk factors in a representative sample of US whites and to derive comparable risk thresholds for WC and BMI. DESIGN: Data on 9019 white participants of the third National Health and Nutrition Examination Survey were divided into 2 groups according to the presence of >or= 1 of 4 obesity-associated risk factors: low HDL cholesterol, high LDL cholesterol, high blood pressure, and high glucose. Odds ratio (OR) equations were derived from logistic regression models for WC and BMI with the use of the 25th percentile in the study population as the reference. Receiver operating characteristic curves for identifying risk factors were computed for WC and BMI. RESULTS: At BMIs of 25 and 30, ORs were 1.19 (95% CI: 1.06, 1.35) and 2.37 (95% CI: 1.33, 4.22) for men and 1.56 (95% CI: 1.29, 1.91) and 3.16 (95% CI: 1.94, 5.28) for women, respectively. The corresponding ORs for WC were at 90 and 100 cm for men and at 83 and 93 cm for women. Minima on the receiver operating characteristic curves for men were at 96 cm for WC and at 26 for BMI and for women were at 86 cm for WC and 25 for BMI. CONCLUSION: WC is more closely linked to cardiovascular disease risk factors than is BMI.     

Body mass index (BMI) and waist circumference (WC) as screening tools for cardiovascular risk factors in Guadeloupean women

Hypertension, dyslipidemia and type 2 diabetes, important cardiovascular risk factors, are strongly linked to obesity. Body mass index (BMI) and waist circumference (WC) are measures of obesity that can be useful in identifying individuals with these risk factors. We assessed which of the two measures is more informative at the population level. The study population included 5,149 consecutive women aged 18 to 74 recruited in an Health Center of Guadeloupe (FWI) in 1999. The areas under the ROC curves of BMI and WC and their 95% CI were computed and compared. Logistic regression analysis of BMI and WC and the areas under the ROC curves in two separate age groups (18-39 years and 40-74 years) showed that age modifies the discriminant ability of these parameters in identifying the CVD risk factors. Sensitivity equalled specificity at levels between 52-70% for BMI and 55-80% for WC. ROC areas for identifying each risk factors by BMI varied from 0.52 to 0.84 and by WC from 0.55 to 0.88. For the identifying of women with at least one CVD risk factor, in the whole population, the areas under the curves for BMI and WC (respectively, 0.71; 95% CI: 0.69-0.73 and 0.76; 95% CI: 0.74-0.78) were both significantly greater than 0.5. The difference between these correlated areas was 0.04, 95% CI [-0.05, -0.03]. The lowest values of the areas were noted in detecting women with dyslipidemia and the highest in detecting those with type 2 diabetes. Waist circumference, a practical tool that had a higher discriminant ability than BMI in identifying presence or absence of all these risk factors, appears as the best screening tool in this population.     

心血管病传统危险因素与糖尿病及其前期关系

目的探讨传统心血管病危险因素与糖尿病及其前期的关联性,为糖尿病的防治提供参考依据。方法采用随机抽样方法对在浙江省湖州市爱山、龙泉和飞英3个街道共1 197名55～75岁的常住居民进行体格检查和血糖检测,采用Logistic回归分析方法分析传统心血管病危险因素与糖尿病及其前期的关联性。结果 1 197名常住居民中,血糖正常者807名,占67.42%,糖尿病前期者267例,占22.31%,糖尿病者123例,占10.27%;3组人群空腹血糖和餐后2 h血糖值分别为(4.83±0.61)、(5.76±0.61)、(6.99±1.43)mmol/L和(5.46±1.65)、(7.94±2.63)、(13.45±4.01)mmol/L;年龄、体质指数(BMI)、中心性肥胖、腹围、臀围、腰臀比和血压等传统心血管病危险因素在正常血糖组、糖尿病前期组和糖尿病组3组人群中分布不同,差异均有统计学意义(P<0.05);多因素Logistic回归分析结果表明,以正常血糖组为参照组,年龄、BMI、中心性肥胖、腹围、臀围、腰臀比和血压与糖尿病前期存在关联性;以正常血糖组为参照组,年龄、BMI、中心性肥胖、腹围、臀围、腰臀比和血压与糖尿病存在关联性;以糖尿病前期组为参照组,中心性肥胖、腹围和腰臀比与糖尿病存在关联性。结论年龄、BMI、中心性肥胖、腹围、臀围、腰臀比、血压等传统心血管病危险因素与糖尿病及其前期均存在关联性。     

不同体重指数和腰围水平与其他心血管病危险因素聚集的关系

目的探讨不同体重指数(BMI)和腰围水平对人群中其他心血管病危险因素聚集的影响.方法将1992～1994年和1998年在我国不同地区中年人群中进行的2次心血管病危险因素调查资料合并共30 561人,比较不同BMI和腰围分组的研究对象其他心血管病危险因素聚集率和聚集的相对危险,其中危险因素聚集定义为同一研究对象具有高血压、高血清总胆固醇、低高密度脂蛋白胆固醇或空腹血糖异常之中的任意2项或2项以上者.结果随着BMI和(或)腰围的增加,人群其他心血管病危险因素的聚集率呈明显上升趋势, 按BMI分层各组中,男女两性腰围与其他心血管病危险因素的聚集率均呈明显的线性上升趋势,同样在不同的腰围分组中,BMI均与其他心血管病危险因素的聚集率呈明显的线性趋势.男性和女性年龄调整心血管病危险因素聚集率在BMI<24 kg/m2、腰围(男/女)<85/80 cm组分别为11.1%和10.4%,BMI<24 kg/m2、腰围(男/女)85～95.9/80～89.9 cm组分别为24.2%和16.9%, BMI 24.0～27.9 kg/m2、腰围(男/女)<85/80 cm组分别为24.0%和17.0%,BMI 24～27.9 kg/m2、腰围(男/女)85～95.9 /80～89.9 cm组分别为34.3%和24.0%. BMI 24.0～27.9 kg/m2、腰围(男/女)≥95/90 cm组分别为40.8%和29.6%,BMI≥28 kg/m2、腰围(男/女)85～95.9/80～89.9 cm组分别为44.2%和29.9%,BMI≥28 kg/m2、腰围(男/女)≥95/90 cm组分别为54.7%和35.4%.结论 BMI和腰围水平均与其他心血管病危险因素的聚集有独立的正相关性.保持BMI和腰围均在正常范围对心血管健康是很重要的.     

Relationship of total and abdominal adiposity with CRP and IL-6 in women

PURPOSE: To examine the relationship between different measures of adiposity as predictors of C-reactive protein (CRP) and interleukin-6 (IL-6) levels. METHODS: A cross-sectional study of 733 women free from preexisting cardiovascular disease or cancer at baseline. MEASUREMENTS: Total adiposity, as measured by body mass index (BMI). Abdominal adiposity, as measured by waist circumference (WC) and waist/hip ratio (WHR). High sensitivity CRP levels and IL-6 levels. RESULTS: BMI, WHR, and WC were all significantly correlated with CRP and IL-6, throughout the anthropometric spectrum. After adjustment for risk factors, the odds ratios (ORs) were 12.2 (95% CI, 6.44-23.0) for elevated CRP (>/=75th percentile) and 4.13 (95% CI, 2.37-7.18) for elevated IL-6 (>/=75th percentile) in comparisons of extreme BMI quartiles. Among women in the highest WC quartile, the OR for elevated CRP and IL-6 were 8.57 (95% CI, 4.59-16.0) and 4.40 (95%CI, 2.46-7.89), while ORs for the highest WHR quartile were 2.88 (95% CI, 1.60-5.19) and 1.76 (95% CI, 1.03-3.01), respectively. Compared with lean nonusers, women in the highest BMI quartile who did not use hormone therapy (HT) had an OR for elevated CRP of 7.79 (95% CI, 2.08-29.2) vs. 31.6 (95% CI, 7.97-125.6) for current hormone users. CONCLUSIONS: Indices of both total and abdominal adiposity were strongly associated with significant increased levels of CRP and IL-6. This association was evident across the entire spectrum of BMI.     

Body mass index and waist circumference in midchildhood and adverse cardiovascular disease risk clustering in adolescence

BACKGROUND: Body mass index (BMI) may not indicate the level of central adiposity associated with the clustering of cardiovascular disease (CVD) risk factors. Hence, it has been recommended that waist circumference be used as an alternative measure. OBJECTIVE: The objective was to investigate whether waist circumference in midchildhood is more effective at predicting cardiovascular disease risk clustering in adolescence than is BMI. DESIGN: Anthropometric measurements were made in 342 children aged 8 y. Seven years later, anthropometric measurements were made in 290 participants, and metabolic profiles were determined in 172 participants. RESULTS: At 15 y, between 9.4% and 11.0% of adolescents were defined as having CVD risk clustering. Children who were overweight or obese at 8 y of age were 7 times (odds ratio: 6.9; 95% CI: 2.5, 19.0; P < 0.001) as likely to have CVD risk clustering in adolescence than were their peers who were not overweight or obese. Those with an increased waist circumference at 8 y were 4 times (3.6; 1.0, 12.9; P = 0.061) as likely to have CVD risk clustering in adolescence than were children with a smaller waist circumference. Neither BMI nor waist circumference were predictive of CVD risk clustering if adiposity was not included as a risk factor. CONCLUSIONS: The association between measures of adiposity in midchildhood and later adverse CVD risk is a result of the tracking of adiposity status. Our results do not support the need to measure waist circumference in children, in addition to BMI, to identify those at increased risk of CVD risk factor clustering in adolescence.     

Discrimination of health risk by combined body mass index and waist circumference

OBJECTIVE: NIH Clinical Guidelines (1998) recommend the measurement of waist circumference (WC, centimeters) within body mass index (BMI, kilograms per square meter) categories as a screening tool for increased health risk. RESEARCH METHODS AND PROCEDURES: The Canada Heart Health Surveys (1986 through 1992) were used to describe the prevalence of the metabolic syndrome in Canada and to test the use of the NIH guidelines for predicting metabolic risk factors. The sample included 7981 participants ages 20 to 74 years who had complete data for WC, BMI, high-density lipoprotein-cholesterol, triglycerides, diabetic status, and systolic and diastolic blood pressures. National Cholesterol Education Program Adult Treatment Panel III risk categories were used to identify the metabolic syndrome and associated risk factors. Logistic regression was used to test the hypothesis that WC improves the prediction of the metabolic syndrome, within overweight (25 to 29.9 kg/m(2)) and obese I (30 to 34.9 kg/m(2)) BMI categories. RESULTS: The prevalence of the metabolic syndrome was 17.0% in men and 13.2% in women. The odds ratios (OR) for the prediction of the metabolic syndrome were elevated in overweight [OR, 1.85; 95% confidence interval (95%CI), 1.02 to 3.35] and obese (OR, 2.35; 95%CI, 1.25 to 4.42) women with a high WC compared with overweight and obese women with a low WC, respectively. On the other hand, WC was not predictive of the metabolic syndrome or component risk factors in men, within BMI categories. DISCUSSION: In women already at increased health risk because of an elevated BMI, the additional measurement of WC may help identify cardiovascular risk.     

Central obesity and risk of cardiovascular disease in the Asia Pacific Region

This paper compares body mass index, waist circumference, hip circumference, and waist-hip ratio as risk factors for ischaemic heart disease and stroke in Asia Pacific populations. We undertook a pooled analysis involving six cohort studies (45 988 participants) and used Cox proportional hazards regression to assess the associations of the four anthropometric indices with stroke and ischaemic heart disease by age, sex and region. During a mean follow-up of six years, 346 stroke and 601 ischaemic heart disease events (fatal and non-fatal) were documented. Overall, a one-standard deviation increase in index was associated with an increase in risk of ischaemic heart disease of 17% (95% CI 7-27%) for body mass index, 27% (95% CI 14-40%) for waist circumference, 10% (95% CI 1-20%) for hip circumference, and 36% (95% CI 21-52%) for waist-hip ratio. There were no significant differences between age groups, sex, and region. None of the four anthropometric indices had a strong association with risk of stroke. These data indicate that measures of central obesity such as waist circumference and waist-hip ratio are strongly associated with risk of ischaemic heart disease in this region. Therefore, we suggest that, along with calculation of body mass index, measures of central obesity such as waist circumference and waist-hip ratio should be undertaken routinely.     

Waist circumference and mortality

The authors examined the association between waist circumference and mortality among 154,776 men and 90,757 women aged 51-72 years at baseline (1996-1997) in the NIH-AARP Diet and Health Study. Additionally, the combined effects of waist circumference and body mass index (BMI; weight (kg)/height (m)(2)) were examined. All-cause mortality was assessed over 9 years of follow-up (1996-2005). After adjustment for BMI and other covariates, a large waist circumference (fifth quintile vs. second) was associated with an approximately 25% increased mortality risk (men: hazard ratio (HR) = 1.22, 95% confidence interval (CI): 1.15, 1.29; women: HR = 1.28, 95% CI: 1.16, 1.41). The waist circumference-mortality association was found in persons with and without prevalent disease, in smokers and nonsmokers, and across different racial/ethnic groups (non-Hispanic Whites, non-Hispanic Blacks, Hispanics, and Asians). Compared with subjects with a combination of normal BMI (18.5-<25) and normal waist circumference, those in the normal-BMI group with a large waist circumference (men: > or =102 cm; women: > or =88 cm) had an approximately 20% higher mortality risk (men: HR = 1.23, 95% CI: 1.08, 1.39; women: HR = 1.22, 95% CI: 1.09, 1.36). The finding that persons with a normal BMI but a large waist circumference had a higher mortality risk in this study suggests that increased waist circumference should be considered a risk factor for mortality, in addition to BMI.     

Decreased muscle mass and increased central adiposity are independently related to mortality in older men

BACKGROUND: Aging is associated with significant changes in body composition. Body mass index (BMI; in kg/m(2)) is not an accurate indicator of overweight and obesity in the elderly. OBJECTIVE: We examined the relation between other anthropometric indexes of body composition (both muscle mass and body fat) and all-cause mortality in men aged 60-79 y. DESIGN: The study was a prospective study of 4107 men aged 60-79 y with no diagnosis of heart failure and who were followed for a mean period of 6 y, during which time there were 713 deaths. RESULTS: Underweight men (BMI < 18.5) had exceptionally high mortality rates. After the exclusion of these men, increased adiposity [BMI, waist circumference (WC), and waist-to-hip ratio] showed little relation with mortality after adjustment for lifestyle characteristics. Muscle mass [indicated by midarm muscle circumference (MAMC)] was significantly and inversely associated with mortality. After adjustment for MAMC, obesity markers, particularly high WC (>102 cm) and waist-to-hip ratio (top quartile), were associated with increased mortality. A composite measure of MAMC and WC most effectively predicted mortality. Men with low WC ( 102 cm and above-median muscle mass showed significantly increased mortality [age-adjusted relative risk: 1.36; 95% CI: 1.07, 1.74), and this increased to 1.55 (95% CI: 1.01, 2.39) in those with WC > 102 and low MAMC. CONCLUSION: The findings suggest that the combined use of both WC and MAMC provides simple measures of body composition to assess mortality risk in older men.     

Obesity, abdominal obesity, and clustering of cardiovascular risk factors in South Korea

The aim of this study was first, to investigate the prevalence of obesity, abdominal obesity, and clustering of cardiovascular (CVD) risk factors, and secondly, to identify the BMI or waist circumference (WC) level at which clustering increases in South Koreans. A population-based, cross-sectional National Health Examination Survey was carried out in 1998. A total of 8,816 subjects (4,029 men and 4,787 women) aged 15-79 y were selected by stratified multistage probability sampling design. The measurements taken of the subjects included: height, weight, waist and hip circumference, blood pressure, fasting glucose, and lipids. The prevalence of BMI > or = 25 kg/m2 was 25.3% for men and 28.3% for women. The prevalence of WC >90 cm in men, and >80 cm in women was 18.5%, and 38.5%, respectively. Clustering of 3 or more CVD risk factors was 22.7% in men ad 21.7% in women. Using <21 kg/m2; as a referent, subjects with BMI of 23 kg/m2; and 27 kg/m2; had an odds ratio of 3.5 and 10.2 in men, and 3.1 and 6.7 in women, respectively for clustering of CVD risk factors. Using <65 cm as a referent, subjects with a WC of > or = 90 cm in men and > or = 85 cm in women had an odds ratio of 13.4, and 13.6, respectively for clustering of CVD risk factors. Considering the significant associations between clustering of CVD risk factors and BMI or WC, the present study suggests that high prevalence of overweight may have important implications for the health care system, even at a lower level of BMI or WC.     

Body mass index, waist circumference, and risk of coronary heart disease: a prospective study among men and women

OBJECTIVE: The purpose of the study was to assess the risk of CHD associated with excess weight measured by BMI and waist circumference (WC) in two large cohorts of men and women. DESIGN, SETTING, SUBJECTS: Participants in two prospective cohort studies, the Health Professionals Follow-up Study (N = 27,859 men; age range 39-75 years) and the Nurses' Health Study (N = 41,534 women; 39-65 years) underwent 16-year follow-up through 2004. RESULTS: 1,823 incident cases of CHD among men and 1,173 cases among women were documented. Compared to men with BMI 18.5 to 22.9 kg/m2, those with a BMI > 30.0 kg/m2 had a multivariate-adjusted RR of CHD of 1.81 (95% CI 1.48 - 2.22). Among women, those with a BMI > 30.0 kg/m2 had a RR of CHD of 2.16 (95% CI 1.81 - 2.58). Compared to men with a WC < 84.0 cm, those with WC of greater than 102.0 cm had a RR of 2.25 (95% CI 1.77 - 2.84). Among women, the RR of CHD was 2.75 (95% CI 2.20 - 3.45) for those with WC of greater than 88.0 cm. CONCLUSIONS: In these analyses from two large ongoing prospective cohort studies, both BMI and WC strongly predicted future risk of CHD. Furthermore, WC thresholds as low as 84.0 cm in men and 71.0 cm in women may be useful in identifying those at increased risk of developing CHD. The findings have broad implications in terms of CHD risk assessment in both clinical practice and epidemiologic studies.     

Body mass index and waist circumference in relation to lung cancer risk in the Women's Health Initiative

Investigators in several epidemiologic studies have observed an inverse association between body mass index (BMI) and lung cancer risk, while others have not. The authors used data from the Women's Health Initiative to study the association of anthropometric factors with lung cancer risk. Over 8 years of follow-up (1998-2006), 1,365 incident lung cancer cases were ascertained among 161,809 women. Cox proportional hazards models were used to estimate hazard ratios adjusted for covariates. Baseline BMI was inversely associated with lung cancer in current smokers (highest quintile vs. lowest: hazard ratio (HR) = 0.62, 95% confidence interval (CI): 0.42, 0.92). When BMI and waist circumference were mutually adjusted, BMI was inversely associated with lung cancer risk in both current smokers and former smokers (HR = 0.40 (95% CI: 0.22, 0.72) and HR = 0.61 (95% CI: 0.40, 0.94), respectively), and waist circumference was positively associated with risk (HR = 1.56 (95% CI: 0.91, 2.69) and HR = 1.50 (95% CI: 0.98, 2.31), respectively). In never smokers, height showed a borderline positive association with lung cancer. These findings suggest that in smokers, BMI is inversely associated with lung cancer risk and that waist circumference is positively associated with risk.     

老年人群体质指数和腰围与心血管病危险因素聚集的研究

目的探讨老年人群体质指数、腰围与心血管病危险因素聚集的关系。方法对654名老年人进行健康查体,对不同体质指数（BMI）、腰围（WC）老年人的收缩压（SBP）、舒张压（DBP）、总胆固醇（TC）、甘油三酯（TG）、高密度脂蛋白胆固醇（HDL-C）和空腹血糖（FPG）平均水平及高血压、高TC、高TG、低HDL-C、糖尿病检出率进行分析,对心血管病危险因素聚集性进行分析。结果BMI、WC升高是老年人最常见的心血管病危险因素。随着BMI、WC的增加,老年人SBP、DBP、TC、TG、FPG平均水平明显升高,HDL-C平均水平降低,高血压、高TC、高TG、糖尿病的检出率明显增高。BMI为24．0～27．9ks／m^2时,老年人高血压、高TC、高TG、糖尿病的检出率分别为59．74％、3．89％、28．57％、10．06％,患高血压、高TG、糖尿病的危险性分别是正常BMI的1．65、1．88、1．85倍;BMI≥28．0ks／m^2时,老年人高血压、高TC、高TG、糖尿病的检出率分别为83．05％、5．08％、35．59％、15．25％,患高血压、高TG、糖尿病的危险性分别是正常BMI的5．44、2．60、2．98倍。男性WC≥85cm、女性WC≥80cm时,老年人高血压、高TC、高TG、糖尿病的检出率分别为66．15％、4．47％、29．57％、10．12％,患高血压、高TC、高TG的危险性分别是正常WC的3．52、6．51、1．68倍。BMI≥24．0kg／m^2或男性WC≥85cm、女性WC≥80cm的老年人伴随多个心血管病危险因素的比例显著增高。结论BMI、WC升高是导致老年人群心血管病危险因素聚集的重要因素。     

Obesity measures and risk of venous thromboembolism and myocardial infarction

Obesity is a risk factor for arterial and venous thromboembolism. However, it is not known whether obesity mediates risk through shared mechanisms. In a population-based cohort, we aimed to compare the impact of obesity measures on risk of venous thromboembolism (VTE) and myocardial infarction (MI), and explore how obesity-related atherosclerotic risk factors influenced these relationships. Measures of body composition including body mass index , waist circumference (WC), hip circumference (HC), waist-hip ratio (WHR) and waist-to-height ratio (WHtR) were registered in 6,708 subjects aged 25–84 years, who participated in the Tromsø Study (1994–1995). Incident VTE- and MI-events were registered until January 1, 2011. There were 288 VTEs and 925 MIs during a median of 15.7 years of follow-up. All obesity measures were related to risk of VTE. In linear models, WC showed the highest risk estimates in both genders. In categorized models (highest versus lowest quintile), WC showed highest risk in men (HR 3.59; 95 % CI 1.82–7.06) and HC in women (HR 2.27; 95 % CI 1.54–4.92). Contrary, WHR and WHtR yielded the highest risk estimates for MI. The HR of MI (highest vs. lowest quintile) for WHR was 2.11 (95 % CI 1.59–2.81) in men and 1.62 (95 % CI 1.13–2.31) in women. The risk estimates for MI were substantially attenuated after adjustment for atherosclerotic risk factors, whereas the estimates for VTE remained unchanged. Our findings suggest that the impact of body fat distribution, and the causal pathway, differs for the association between obesity and arterial and venous thrombosis.     

Waist-hip ratio and waist circumference associated with body mass index in a study with schoolchildren

The objectives of this study were to determine the percentile levels of the anthropometric indices body mass index (BMI), waist-hip ratio (WHR), and waist circumference (WC) and to verify possible correlations among theses indices in schoolchildren registered at the State Institute of Education, Florianópolis, Santa Catarina State, Brazil. A total of 419 children ages 7 to 9 years were investigated: 215 (51.3%) boys and 204 (48.7%) girls. BMI, WHR, and WC were higher for boys than for girls. However, the differences were only statistically significant for WHR and WC. Prevalence rates were 17.9% for overweight and 6.7% for obesity. The anthropometric indices with the highest correlation were BMI and WC (r = 0.87 and p < 0.01). For overweight, BMI and WC also presented the strongest correlation (r = 0.74). For obesity, WHR and WC showed the best correlation (r = 0.54).     

BMI与腰围对阻塞性睡眠呼吸暂停与2型糖尿病的中介效应

目的  探究BMI和腰围(waist circumference, WC)对阻塞性睡眠呼吸暂停(obstructive sleep apnea, OSA)与2型糖尿病、糖代谢连续测量指标之间的中介效应。方法  纳入分析的1 615名研究对象来自动脉粥样硬化多民族研究(Multi-Ethnic Study of Atherosclerosis, MESA)。OSA评价指标为呼吸暂停低通气指数(apnea-hypopnea index,AHI),由多导睡眠图测定。糖代谢连续测量指标包括FPG和糖化血红蛋白(glycated hemoglobin,HbA1c)。肥胖指标包括全身肥胖指标BMI和腹型肥胖指标WC。结果  OSA与2型糖尿病显著相关,后者的患病风险随OSA严重程度增加而升高(P < 0.001)。BMI和WC均介导重度OSA与2型糖尿病之间的关联,其中腹型肥胖指标WC的中介效应为1.296(95% CI: 1.182~1.466),中介效应比例为56.397%;BMI的中介效应为1.291(95% CI: 1.173~1.479),中介效应比例为55.400%。BMI和WC同样介导重度OSA与FPG、HbA1c之间的关联。结论  OSA与2型糖尿病、FPG和HbA1c的关系,与肥胖程度增加有关。提示OSA患者通过早期的体重干预,特别是控制腹型肥胖对降低糖尿病和心血管并发症的患病率具有重要意义。     

Waist circumference, waist:hip ratio, and risk of breast cancer in the Nurses' Health Study

This study examined prospectively the associations of waist circumference and waist:hip circumference ratio with risk of breast cancer. A total of 47,382 US registered nurses who reported their waist and hip circumferences in 1986 were followed up through May 1994 for identification of incident cases of breast cancer. During 333,097 person-years of follow-up, 1,037 invasive breast cancers were diagnosed. In proportional hazards analyses, waist circumference was nonsignificantly related to risk of premenopausal breast cancer but was significantly associated with postmenopausal breast cancer after adjustment for established breast cancer risk factors (for the highest quintile of waist circumference vs. the lowest, relative risk (RR) = 1.34; 95% confidence interval (CI): 1.05, 1.72). When the analysis was limited to postmenopausal women who had never received hormone replacement therapy, a stronger positive association was found (RR = 1.88; 95% CI: 1.25, 2.85). After the data were further controlled for body mass index, the positive association was only slightly attenuated (RR = 1.83; 95% CI: 1.12, 2.99). Among past and current postmenopausal hormone users, no significant associations were found. Similar but slightly weaker associations were observed between waist:hip ratio and breast cancer risk. These data suggest that greater waist circumference increases risk of breast cancer, especially among postmenopausal women who are otherwise at lower risk because of never having used estrogen replacement hormones.     

Associations of hip and thigh circumferences independent of waist circumference with the incidence of type 2 diabetes: the Hoorn Study

BACKGROUND: The higher risk of type 2 diabetes in persons with a high waist-to-hip ratio (WHR) or waist-to-thigh ratio (WTR) has mostly been attributed to increased visceral fat accumulation. However, smaller hip or thigh circumference may also explain the predictive value of the WHR or WTR for type 2 diabetes. OBJECTIVE: This study considered prospectively the association of hip and thigh circumferences, independent of waist circumference, with the incidence of type 2 diabetes. DESIGN: The Hoorn Study is a population-based cohort study of diabetes. A total of 1357 men and women aged 50-75 y and nondiabetic at baseline participated in the 6-y follow-up examination. Glucose tolerance was assessed by use of a 75-g oral-glucose-tolerance test. Baseline anthropometric measurements included body mass index (BMI) and waist, hip, and thigh circumferences. RESULTS: Logistic regression analyses showed that a 1-SD larger hip circumference gave an odds ratio (OR) for developing diabetes of 0.55 (95% CI: 0.36, 0.85) in men and 0.63 (0.42, 0.94) in women, after adjustment for age, BMI, and waist circumference. The adjusted ORs for a 1-SD larger thigh circumference were 0.79 (0.53, 1.19) in men and 0.64 (0.46, 0.93) in women. In contrast with hip and thigh circumferences, waist circumference was positively associated with the incidence of type 2 diabetes in these models (ORs ranging from 1.60 to 2.66). CONCLUSION: Large hip and thigh circumferences are associated with a lower risk of type 2 diabetes, independently of BMI, age, and waist circumference, whereas a larger waist circumference is associated with a higher risk.     

Association of age at menarche with cardiovascular risk factors, vascular structure, and function in adulthood: the Cardiovascular Risk in Young Finns study

BACKGROUND: It is unclear whether age at menarche is an independent determinant of future cardiovascular risk. OBJECTIVE: We aimed to determine whether menarcheal age is an independent predictor of body mass index (BMI) and a wide range of cardiovascular risk factors in adolescence and adulthood. DESIGN: We examined the associations of menarcheal age with BMI (in kg/m(2)) and other cardiovascular risk factors in adolescence and adulthood in a population-based sample of 794 female adolescents aged 9-18 y at baseline. Their age at first menstruation was requested at baseline and again 3 and 6 y later. Cardiovascular risk factors were assessed at baseline and at age 30-39 y. RESULTS: A 1-y decrease in menarcheal age was associated with 0.81 (95% CI: 0.53, 1.08) higher adult BMI as well as greater waist circumference and waist-to-hip ratio, elevated systolic blood pressure, higher insulin resistance, and greater risk of metabolic syndrome (P < 0.05 for all). In multivariable analysis in which these adult risk factors were mutually adjusted for, only the inverse association between age at menarche and adult BMI remained. However, this inverse association was lost after adjustment for premenarcheal BMI (beta: -0.16; 95% CI -0.55, 0.23; P = 0.42). Higher premenarcheal BMI predicted earlier menarche, and the strong association between premenarcheal BMI and adult BMI was robust to adjustment for age at menarche. CONCLUSIONS: These findings suggest that early menarche is only a risk marker. Greater childhood BMI seems to contribute to earlier age at menarche and, because of tracking, greater adult BMI and associated cardiovascular risk. An independent effect of early menarche on adult adiposity cannot be excluded, but it is likely to be small at best.