Central obesity: predictive value of skinfold measurements for subsequent ischaemic heart disease at 14 years follow-up in the Caerphilly Study

The association between anthropometric indices and ischemic heart disease: a large-scale cross-sectional study on the Iranian population

This study aimed to evaluate the superiority of anthropometric indices compared to others for predicting ischemic heart disease (IHD) or cardiometabolic risk factors. This study was a cross-sectional analysis of the Pars Cohort Study data. In total, 9229 Valashahr inhabitants aged 40-75 were included in the analysis. The area under the receiver operating characteristic curve (AUC) analyses was used to compare the predictive accuracy of four anthropometric measures, including body mass index, waist to height ratio (WHtR), waist to hip ratio (WHR), and waist circumference (WC). IHD prevalence was 10.4% in our sample. The prevalence of diabetes mellitus (DM), hypertension, dyslipidemia, and metabolic syndrome was 12.7%, 29.2%, 58.4%, and 22.3%, respectively. All anthropometric indices had poor to good accuracy in predicting IHD risk factors, with AUCs ranging between 0.580 and 0.818. WHR was the most accurate measure for predicting IHD in both genders. All indexes had a better accuracy for predicting DM, dyslipidemia, and metabolic syndrome (MetS) in males than in females. To conclude, anthropometric measures, especially WC and WHtR, are recommended for predicting metabolic syndrome in primary prevention settings. These simple indices could help physicians find those who need further evaluation for MetS.

Associations Between Adult Triceps Skinfold Thickness and All-Cause, Cardiovascular and Cerebrovascular Mortality in NHANES 1999–2010: A Retrospective National Study

Background:

The association between triceps skinfold (TSF) thickness and mortality in previous studies was controversial. This study aimed to explore how TSF thickness affects all-cause, cardiovascular, and cerebrovascular mortality among the United States (U.S.) general population.

Methods

Our research included 25,954 adults in the National Health and Nutrition Examination Survey (NHANES) from 1999 to 2010. Participants were categorized by the baseline TSF quartiles [quartile 1 (Q1): < 11.8, (Q2): 11.8–17.4, (Q3): 17.4–25, and (Q4): ≥25; unit: millimeter (mm)]. Cox regression models were used to assess the association of TSF with all-cause, cardiovascular, and cerebrovascular mortality. The association between mid-arm muscle circumference (MAMC) and mortality was also explored. Subgroup analyses were conducted to assess heterogeneity in different subgroups.

Results

The highest TSF group (Q4) had the lowest risk to experience all-cause (HR, 0.46; 95% CI, 0.38–0.59; P < 0.001) and cardiovascular mortality (HR, 0.35; 95% CI, 0.23–0.54; P < 0.001) than the lowest TSF group (Q1) after multivariate adjustment. However, there was no relationship between TSF quartiles and cerebrovascular mortality (HR, 0.98; 95%CI, 0.42–2.30; P = 0.97). The protective effects of TSF thickness on mortality still existed after adjusting for BMI and MAMC. For every 1 mm increase in TSF thickness, the risk of all-cause and cardiovascular death decreased by 4% (HR, 0.96; 95% CI, 0.95–0.97; P < 0.001) and 6% (HR, 0.94; 95% CI, 0.93–0.96; P < 0.001), respectively. In the stratified analysis, the relationships between TSF and mortality risk were generally similar across all subgroups.

Conclusions

Higher TSF thickness was associated with lower all-cause and cardiovascular mortality, independent of BMI and MAMC. Our study revealed that the TSF thickness may be a convenient and credible indicator to predict mortality, especially in those with severe cardiovascular diseases.

The Association of Subscapular Skinfold with All-Cause, Cardiovascular and Cerebrovascular Mortality

Purpose

Previous studies suggested inconsistent relationship between subscapular skinfold and all-cause, cardiovascular, and cerebrovascular mortality. Therefore, the present study aimed to investigate the associations between subscapular skinfold with all-cause, cardiovascular, and cerebrovascular mortality.

Patients and Methods

Data were collected from the National Health and Nutrition Examination Survey (NHANES, 1999–2006) with follow-up data through 31 December 2015. Participants were categorized by subscapular skinfold quartiles. The hazard ratios (HRs) and 95% confidence intervals (CIs) were evaluated using the multivariate Cox regression model and subgroup analysis. Kaplan–Meier curves were used to present cause-specific mortalities and used Cox cubic regression splines to examine the association of subscapular skinfold with cause-specific mortalities.

Results

A total of 16,402 subjects (49.61% male) were involved in our study. After a mean follow-up of 141.73 months, there were 3078 (18.77%), 392 (2.39%), and 128 (0.78%) cases of all-cause, cardiovascular, and cerebrovascular mortality, respectively. Participants in the highest quartile of subscapular skinfold (≥24.80mm) versus the lowest (<13.20mm) had lower risk for all-cause mortality (HR, 0.71; 95% CI, 0.57–0.89; P for trend = 0.007) and cardiovascular mortality (HR, 0.44; 95% CI, 0.23–0.83; P for trend = 0.023) in the fully adjusted model. In the age-stratified analysis, subscapular skinfold was only inversely associated with all-cause and cardiovascular disease mortality in people ≥65 years of age (all P-interaction <0.001). No significant difference was found between subscapular skinfold and cerebrovascular mortality (all P > 0.05).

Conclusion

Subscapular skinfold showed an inverse association with all-cause and cardiovascular disease mortality in people aged ≥65 years.

Obesity and Coronary Heart Disease: Epidemiology, Pathology, and Coronary Artery Imaging

Overweight and obesity contribute to the development of cardiovascular disease (CVD) in general and coronary heart disease (CHD) in particular in part by their association with traditional and nontraditional CVD risk factors. Obesity is also considered to be an independent risk factor for CVD. The metabolic syndrome, of which central obesity is an important component, is strongly associated with CVD including CHD. There is abundant epidemiologic evidence of an association between both overweight and obesity and CHD. Evidence from postmortem studies and studies involving coronary artery imaging is less persuasive. Recent studies suggest the presence of an obesity paradox with respect to mortality in persons with established CHD. Physical activity and preserved cardiorespiratory fitness attenuate the adverse effects of obesity on CVD events. Information concerning the effect of intentional weight loss on CVD outcomes in overweight and obese persons is limited.

Dietary patterns and hearing loss in older men enrolled in the Caerphilly Study

The association between dietary patterns (DP) and prevalence of hearing loss in men enrolled in the Caerphilly Prospective Study was investigated. During 1979-1983, the study recruited 2512 men aged 45-59 years. At baseline, dietary data were collected using a semi-quantitative FFQ, and a 7-d weighed food intake (WI) in a 30 % subsample. Five years later, pure-tone unaided audiometric threshold was assessed at 0·5, 1, 2 and 4 kHz. Principal component analysis (PCA) identified three DP and multiple logistic and ordinal logistic regression models examined the association with hearing loss (defined as pure-tone average of frequencies 0·5, 1, 2 and 4 kHz &gt;25 dB). Traditional, healthy and high-sugar/low-alcohol DP were found with both FFQ and WI data. With the FFQ data, fully adjusted models demonstrated significant inverse association between the healthy DP and hearing loss both as a dichotomous variable (OR=0·83; 95 % CI 0·77, 0·90; P&lt;0·001) and as an ordinal variable (OR=0·87; 95 % CI 0·81, 0·94; P&lt;0·001). With the WI data, fully adjusted models showed a significant and inverse association between the healthy DP and hearing loss (OR=0·85; 95 % CI 0·73, 0·99; P&lt;0·03), and a significant association between the traditional DP (per fifth increase) and hearing loss both as a dichotomous variable (OR=1·18; 95 % CI 1·02, 1·35; P=0·02) and as an ordinal variable (OR=1·17; 95 % CI 1·03, 1·33; P=0·02). A healthy DP was significantly and inversely associated with hearing loss in older men. The role of diet in age-related hearing loss warrants further investigation.

Dairy Foods and Body Mass Index over 10-Year: Evidence from the Caerphilly Prospective Cohort Study

The association between dairy product consumption and body mass index (BMI) remains controversial. The aim of the present study was to investigate the association between total dairy, milk, cheese, cream and butter consumption and BMI change over a 10-year follow-up by using long-term follow-up cohort data from the Caerphilly Prospective Cohort Study (CAPS). The CAPS included 2512 men aged 45⁻59 years at baseline, who were followed up at 5-year intervals for over 20-year. A semi-quantitative food frequency questionnaire estimated the intake of dairy consumption, including milk, cheese, cream and butter at baseline, 5-year and 10-year follow-up. In total, men free of cardiovascular disease, diabetes and cancer (n = 1690) were included in current analysis. General linear regression and logistic regression were used for data analysis. The results showed higher cheese consumption was associated with lower BMI at the 5-year follow-up (p = 0.013). There was no evidence that higher consumption of total dairy, milk, cream and butter were significantly associated with BMI during the over the 10-year following-up. This study suggest that cheese consumption have beneficial effects on lowering BMI, which needs further investigation.

Skinfold thickness measurements and mortality in white males during 27.7 years of follow-up

INTRODUCTION

Obesity is a major risk factor for mortality from a range of causes. We investigated whether skinfold measurements were associated with mortality independently of variation in body mass index (BMI).

METHODS

A prospective analysis of mortality in 870 apparently healthy adult Caucasian men participating in an occupational health cohort was undertaken. At baseline, skinfold measurements were taken at biceps, triceps, iliac and subscapular sites. Derived measurements included the sum of all four skinfolds and subscapular to triceps, subscapular to iliac and BMI to iliac ratios. All-cause mortality was analysed by Cox proportional hazards modelling and death in specific mortality subcategories by competing risks analysis.

RESULTS

During a mean of 27.7 years follow up, there were 303 deaths (119 cancer, 101 arteriovascular, 40 infection, 43 other). In univariable analysis, BMI was associated with all-cause, cancer, arteriovascular and other mortality and subscapular skinfold with all-cause and arteriovascular mortality. On bivariable analysis, with inclusion of BMI, subscapular skinfold ceased to be a associated with mortality but iliac skinfold emerged as strongly, negatively associated with all-cause and arteriovascular mortality. In multivariable analysis, with inclusion of age, BMI, smoking, alcohol and exercise, iliac skinfold was negatively associated with all-cause (Hazard ratio HR 0.77, 95% confidence interval CI 0.66-0.90, p = 0.002), arteriovascular (HR 0.75, 95%CI 0.58,0.97, p = 0.02) and infection (HR 0.63, 95%CI 0.42,0.94, p = 0.02) death. Among obese participants (BMI ≥ 30 kg/m²), iliac skinfold of ≤9.7 mm was associated with a six-fold increase in all-cause mortality risk.

CONCLUSION

Low iliac skinfold thickness is an independent risk factor for all-cause mortality in adult white males with risk apparently concentrated among people who are obese.

Sex inequalities in cardiovascular health: a cross-sectional study

BACKGROUND

The aim of this study was to determine sex differences in the prevalence of cardiovascular health (CVH) metrics according to the CVH status.

METHODS

The cross-sectional, population-based study involved 2250 women and 1920 men aged ≥18 years that participated in the 2010 National Health Survey in the Republic of Srpska, Bosnia and Herzegovina. Prevalence of CVH behaviours (smoking, body mass index, physical activity, diet), CVH factors (cholesterol, fasting blood glucose and blood pressure, plus smoking) and ideal CVH were estimated according to the American Heart Association criteria for ideal, intermediate and poor levels. Association between sex and ideal CVH categories was analyzed with multivariable logistic regression analysis across three age stratums.

RESULTS

A higher prevalence of ideal CVH metrics was seen in women for smoking status, body mass index, healthy diet score and blood pressure, and in men for physical activity and total cholesterol. Women from all age groups had better CVH behaviours (odds ratio [OR] = 1.40 for the youngest; OR = 2.05 for middle-aged; and OR = 2.03 for older-aged women), while only women from the youngest age group had better CVH factors (OR = 5.09). In line with this, ideal overall CVH prevailed in younger and middle-aged women in comparison to men of the same ages (OR = 3.01 and OR = 2.25, respectively), while disappeared in older ones.

CONCLUSIONS

Significant differences in the prevalence of CVH metrics between men and women in the Republic of Srpska should be considered in cardiovascular disease prevention.

Waist:height ratio, waist circumference and metabolic syndrome abnormalities in Colombian schooled adolescents: a multivariate analysis considering located adiposity

Very few large studies in Latin America have evaluated the association between waist:height ratio (W-HtR) and cardiometabolic risk in children and adolescents. Further, multivariable analyses verifying the independence of located subcutaneous fat have not been conducted so far. The aim of this study was to evaluate the associations of W-HtR and waist circumference (WC) with metabolic syndrome abnormalities and high LDL-cholesterol levels in schooled adolescents before and after adjusting for trunk skinfolds and BMI. The sample consisted of 831 boys and 841 girls aged 10–17 years. Biochemical, blood pressure and anthropometrical variables were measured. Age- and sex-specific quartiles of W-HtR and WC were used in Poisson regression models to evaluate the associations. High WC values (highest quartilev. quartiles 1–3) were associated with high TAG levels in both sexes (prevalence ratio, boys: 2·57 (95 % CI 1·91, 3·44); girls: 1·92 (95 % CI 1·49, 2·47);P<0·05), and with high blood pressure specifically in female adolescents (3·07 (95 % CI 1·58, 5·98);P<0·05), independently of trunk skinfolds or BMI (P<0·05). Associations of high WC with high fasting glucose (boys), low HDL-cholesterol and having at least two abnormalities did not remain significant in most of the adjustments for trunk skinfolds or BMI (P>0·05). High W-HtR (highest quartilev. quartiles 1–3) was only independently associated with high TAG in female adolescents (1·99 (95 % CI 1·55, 2·56);P<0·05). In conclusion, WC showed better association with cardiometabolic risk than W-HtR in the children of this study. This observation does not support W-HtR as a relevant adiposity marker for cardiovascular and metabolic risk in adolescence.

BMI-specific waist circumference is better than skinfolds for health-risk determination in the general population

Distribution of fat is important when considering health risk; however, the value added from skinfold measurements (SKF) when using body mass index (BMI) refined by waist circumference (WC) is not well understood. The purpose of this study was to assess the utility of SKF compared with WC in determination of health risk in the general population. Data from the Canadian Health Measures Survey (cycles 1 and 2; N = 5217) were used. Health outcomes included directly measured blood pressure, cholesterol, glycated haemoglobin, lung function, self-reported health, and chronic conditions. Technical errors of measurements (TEM), sensitivity, and specificity analysis and linear regressions were conducted. Data indicated that TEM for SKF was above the acceptable 5% in most age and sex categories. Sensitivity and specificity of chronic conditions was not improved with the inclusion of SKF in models containing WC (in those aged 45-69 years) and SKF did not explain any additional variance in regression models containing WC. Health outcomes for those in the normal weight and overweight BMI category were significantly worse in those classified as high risk based on WC, whereas SKF did not consistently discriminate risk. In conclusion, evidence-based WC cut-points were shown to identify health risk, particularly in normal weight and overweight individuals. Thus, BMI refined by WC appears to be more appropriate than SKF for assessment of body composition when determining health risk in the general population.

Sagittal abdominal diameter to triceps skinfold thickness ratio: a novel anthropometric index to predict premature coronary atherosclerosis

OBJECTIVE

We aimed to compare the accuracy of a novel index defined by us, as a ratio of Sagittal abdominal diameter (SAD) and triceps skinfold thickness (TSF) with other indices of adiposity for prediction of presence, severity and extension of premature coronary artery disease (CAD).

METHODS

A cross-sectional study was conducted on 238 younger patients (females <55 years; males <45 years) who underwent coronary angiography. Anthropometric indices including TSF, SAD, waist circumference, and hip circumference were measured before catheterization and body mass index, waist-to-hip ratio, abdominal diameter index, index of central obesity as well as our proposed index, SAD-to-TSF ratio, were calculated accordingly. Evaluation of severity and extension of coronary stenosis was by Gensini score and extent score, respectively.

RESULTS

After adjustment for age and sex in multivariate regression models, the SAD-to-TSF ratio was the best predictor for the presence (OR = 2.49, 95% CI = 1.44-4.30; p = 0.001) and extension (β = 1.10, p = 0.004) of premature CAD. TSF and the SAD-to-TSF ratio were the only indices that significantly predicted the Gensini score and the correlation remained significant even after adjustment for age and sex (β = -7.28, p < 0.0001 and β = 3.76, p < 0.0001, respectively).

CONCLUSION

We showed that our proposed index, SAD-to-TSF ratio, has a substantially better accuracy than do the known indices of obesity like body mass index, waist circumference, and waist-to-hip ratio for the prediction of premature CAD. Furthermore, our index was the only index that positively correlated with the severity of premature CAD.

The relation of BMI and skinfold thicknesses to risk factors among young and middle-aged adults: the Bogalusa Heart Study

OBJECTIVE

Although adverse levels of cardiovascular disease risk factors are related to skinfold thicknesses and BMI among adults, the relative strengths of these associations are unknown. We examine whether the triceps and subscapular skinfold thicknesses are more strongly related to adult levels of lipids, fasting insulin and blood pressure than BMI.

DESIGN AND SUBJECTS

Cross-sectional (n =3318) and longitudinal (n =1593) analyses of 18- to 44-year-olds examined in the Bogalusa Heart Study from 1983 to 2002. Principal components analysis was used to derive a summary index of the six examined risk factors (triglycerides, low- and high-density lipoprotein cholesterol, insulin, and systolic and diastolic blood pressures).

RESULTS

The magnitudes of the differences were generally small, but all comparisons indicated that BMI was at least as strongly related to adverse risk factor levels as was the sum of subscapular and triceps skinfold thicknesses (SF sum). For example, adjusted cross-sectional associations with the risk factor summary were r = 0.55 (BMI) and r = 0.49 (SF sum), p < 0.001 for difference between correlations. Similar differences were seen in longitudinal analyses, with changes in the risk factor summary being more strongly associated with changes in BMI (r =0.50) than with changes in the SF sum (r = 0.38).

CONCLUSION

BMI appears to be at least as accurate as skinfold thicknesses in identifying metabolic risk among adults. The advantages of BMI should be considered in the design and interpretation of clinical and epidemiologic studies.

Comparison of the associations of body mass index and measures of central adiposity and fat mass with coronary heart disease, diabetes, and all-cause mortality: a study using data from 4 UK cohorts

BACKGROUND

Measures of regional adiposity have been proposed as alternatives to the measurement of body mass index (BMI) for identifying persons at risk of future disease.

OBJECTIVE

The objective was to compare the magnitudes of association of BMI and alternative measurements of adiposity with coronary heart disease, diabetes, and cardiovascular disease risk factors and all-cause mortality.

DESIGN

Data from 4 cohorts of adults [3937 women from the British Women's Heart and Health Study (BWHHS); 2367 and 1950 men from phases 1 and 3, respectively, of the Caerphilly Prospective Study (CaPS); 403 men and women from the Boyd Orr Study; and 789 men and women from the Maidstone-Dewsbury Study] were analyzed.

RESULTS

The magnitudes of associations of BMI with incident coronary heart disease and cardiovascular disease risk factors were similar to those with measurements of central adiposity [waist circumference (WC), waist-hip ratio (WHR), or waist-height ratio (WHtR)] and more direct measurements of fat mass (bioimpedance/skinfold thickness). In CaPS (men only), there was no strong evidence of differences in the strengths of association with incident diabetes between BMI, WC, WHR, and WHtR (P for heterogeneity > 0.49 for all). In the BWHHS (women only), there was statistical evidence that WC [hazard ratio (HR): 2.35; 95% CI: 2.03, 2.73] and WHtR (HR: 2.29; 95% CI: 1.98, 2.66) were more strongly associated with diabetes than with BMI (HR: 1.80; 95% CI: 1.59, 2.04) (P for heterogeneity < 0.02 for both). Central adiposity measurements were positively associated with all-cause mortality, as was BMI, but only when those with a BMI (in kg/m(2)) <22.5 were removed from the analyses.

CONCLUSION

No strong evidence supports replacing BMI in clinical or public health practice with other adiposity measures.

Relation of body mass index and skinfold thicknesses to cardiovascular disease risk factors in children: the Bogalusa Heart Study

BACKGROUND

Adverse levels of cardiovascular disease (CVD) risk factors are related to skinfold thicknesses and body mass index (BMI) among children, but the relative strengths of these associations are unknown.

OBJECTIVE

The objective was to determine whether the sum of the triceps and subscapular skinfold thicknesses (SF sum) is more strongly related to levels of 6 risk factors (triglycerides, LDL and HDL cholesterol, insulin, and systolic and diastolic blood pressure) than is BMI.

DESIGN

Cross-sectional analyses of schoolchildren examined in the Bogalusa Heart Study from 1981 to 1994 (n = 6866) were conducted. A risk factor summary index was derived by using principal components analysis.

RESULTS

After race, sex, study period, and age were controlled for, almost all comparisons indicated that BMI was more strongly related to risk factor levels than was the SF sum. Although the differences were generally small, many were statistically significant. Associations with the risk factor summary, for example, were r = 0.50 for BMI and r = 0.47 for SF sum (P < 0.001 for difference). Furthermore, an adverse risk factor summary was observed among 62% of the children with the highest (upper 5%) BMI levels but among only 54% of children with the highest SF sum levels.

CONCLUSIONS

BMI is at least as accurate as SF sum in identifying children and adolescents who are at metabolic risk. Because of the training and errors associated with skinfold-thickness measurements, the advantages of BMI should be considered in the design and interpretation of clinical and epidemiologic studies.

Association between late-life body mass index and dementia: The Kame Project

OBJECTIVE

To examine the association between body mass index (BMI), waist circumference (WC), and waist-to-hip ratio (WHR) and risk of dementia and its subtypes in late life.

METHODS

Participants were members of the Kame Project, a population-based prospective cohort study of 1,836 Japanese Americans living in King County, WA, who had a mean age of 71.8 years and were dementia-free at baseline (1992-1994), and were followed for incident dementia through 2001. Cox proportional hazards models were used to estimate the risk of dementia, Alzheimer disease (AD), and vascular dementia (VaD) controlling for demographic and lifestyle characteristics and vascular comorbidities as a function of baseline BMI, WC, and WHR and change in BMI over time.

RESULTS

Higher baseline BMI was significantly associated with a reduced risk of AD (hazard ratio [HR] = 0.56, 95% confidence interval [CI] = 0.33-0.97) in the fully adjusted model. Slower rate of decline in BMI was associated with a reduced risk of dementia (HR = 0.37, 95% CI = 0.14-0.98), with the association stronger for those who were overweight or obese (HR = 0.18, 95% CI = 0.05-0.58) compared to normal or underweight (HR = 1.00, 95% CI = 0.18-5.66) at baseline.

CONCLUSION

Higher baseline body mass index (BMI) and slower declining BMI in late life are associated with a reduced risk of dementia, suggesting that low BMI or a faster decline in BMI in late life may be preclinical indicators of an underlying dementing illness, especially for those who were initially overweight or obese.

Primary prevention of coronary heart disease in women

The British Menopause Society Council is committed to provide up-to-date authoritative reviews to aid health professionals to inform and advise women about key issues in postreproductive health. Coronary heart disease (CHD) is a leading cause of death in women. Observational studies have consistently shown estrogen to help prevent CHD in postmenopausal women. The large randomized controlled Women's Health Initiative (WHI) trial did not confirm these observational findings. However, further analyses of the WHI study as well as the observational Nurses' Health Study have now found that the timing of onset of hormone replacement therapy (HRT) use is important and that estrogen may have a protective role in CHD in women aged 50-59 years. This consensus statement will examine the evidence regarding HRT and non-estrogen therapies (lipid lowering agents, aspirin, antihypertensives, antidiabetic medications, selective estrogen receptor modulators [SERMs]) as well as diet, lifestyle and smoking cessation in the primary prevention of CHD in women.

Relation of body mass index and waist-to-height ratio to cardiovascular disease risk factors in children and adolescents: the Bogalusa Heart Study

BACKGROUND

Several investigators have concluded that the waist-to-height ratio is more strongly associated with cardiovascular disease risk factors than is the body mass index (BMI; in kg/m(2)).

OBJECTIVES

We examined the relation of the BMI-for-age z score and waist-to-height ratio to risk factors (lipids, fasting insulin, and blood pressures). We also compared the abilities of these 2 indexes to identify children with adverse risk factors.

DESIGN

Children aged 5-17 y (n=2498) in the Bogalusa Heart Study were evaluated.

RESULTS

As assessed by the ability of the 2 indexes to 1) account for the variability in each risk factor and 2) correctly identify children with adverse values, the predictive abilities of the BMI-for-age z score and waist-to-height ratio were similar. Waist-to-height ratio was slightly better (0.01-0.02 higher R(2) values, P<0.05) in predicting concentrations of total-to-HDL cholesterol ratio and LDL cholesterol, but BMI was slightly better in identifying children with high systolic blood pressure (0.03 higher R(2), P<0.05) in predicting measures of fasting insulin and systolic and diastolic blood pressures. On the basis of an overall index of the 6 risk factors, no difference was observed in the predictive abilities of BMI-for-age and waist-to-height ratio, with areas under the curves of 0.85 and 0.86 (P=0.30) and multiple R(2) values of 0.320 and 0.318 (P=0.79). This similarity likely results from the high intercorrelation (R(2)=0.78) between the 2 indexes.

CONCLUSIONS

BMI-for-age and waist-to-height ratio do not differ in their abilities to identify children with adverse risk factors. Although waist-to-height ratio may be preferred because of its simplicity, additional longitudinal data are needed to examine its relation to disease.

Obesity in middle age and future risk of dementia: a 27 year longitudinal population based study

OBJECTIVE

To evaluate any association between obesity in middle age, measured by body mass index and skinfold thickness, and risk of dementia later in life.

DESIGN

Analysis of prospective data from a multiethnic population based cohort.

SETTING

Kaiser Permanente Northern California Medical Group, a healthcare delivery organisation.

PARTICIPANTS

10,276 men and women who underwent detailed health evaluations from 1964 to 1973 when they were aged 40-45 and who were still members of the health plan in 1994.

MAIN OUTCOME MEASURES

Diagnosis of dementia from January 1994 to April 2003. Time to diagnosis was analysed with Cox proportional hazard models adjusted for age, sex, race, education, smoking, alcohol use, marital status, diabetes, hypertension, hyperlipidaemia, stroke, and ischaemic heart disease.

RESULTS

Dementia was diagnosed in 713 (6.9%) participants. Obese people (body mass index > or = 30) had a 74% increased risk of dementia (hazard ratio 1.74, 95% confidence interval 1.34 to 2.26), while overweight people (body mass index 25.0-29.9) had a 35% greater risk of dementia (1.35, 1.14 to 1.60) compared with those of normal weight (body mass index 18.6-24.9). Compared with those in the lowest fifth, men and women in the highest fifth of the distribution of subscapular or tricep skinfold thickness had a 72% and 59% greater risk of dementia, respectively (1.72, 1.36 to 2.18, and 1.59, 1.24 to 2.04).

CONCLUSIONS

Obesity in middle age increases the risk of future dementia independently of comorbid conditions.