Comparison of predicted body fat percentage from anthropometric methods and from impedance in university students

Validity and agreement between dual-energy X-ray absorptiometry, anthropometry and bioelectrical impedance in the estimation of fat mass in young adults

Introduction

Assessment of fat mass has historically employed various methods like Dual-energy X-ray Absorptiometry (DXA), and bioelectrical impedance (BIA), and anthropometry with its set of formulas. However, doubts persist regarding their validity and interchangeability to evaluate fat mass. This research aimed to determine the validity of anthropometry, and BIA in estimating fat mass Vs DXA, considering the influence of sex and hydration status.

Methods

A descriptive, cross-sectional study included 265 young adults (161 males and 104 females), assessed through DXA, BIA in a standing position, and anthropometry. A fat mass estimation formula with DXA, a fat mass estimation formula with BIA and 10 fat mass estimation formulas with anthropometry were calculated.

Results

Significant differences were found across DXA, BIA and anthropometry in both kilograms and percentages for the overall sample (p<0.001), and when the covariable sex was included (p<0.001), with no significant effect of hydration status (p=0.332-0.527). Bonferroni-adjusted analyses revealed significant differences from DXA with anthropometry and BIA in most cases for the overall sample (p<0.001), as well as when stratified by sex (p<0.001-0.016). Lin's coefficient indicated poor agreement between most of the formulas and methods both in percentage and kilograms of fat mass (CCC=0.135-0.892). In the Bland-Altman analysis, using the DXA fat mass values as a reference, lack of agreement was found in the general sample (p<0.001-0.007), except for Carter's formula in kilograms (p=0.136) and percentage (p=0.929) and Forsyth for percentage (p=0.365). When separating the sample by sex, lack of agreement was found in males for all methods when compared with both percentage and kilograms calculated by DXA (p<0.001). In the female sample, all methods and formulas showed lack of agreement (p<0.001-0.020), except for Evans's in percentage (p=0.058).

Conclusion

The formulas for fat mass assessment with anthropometry and BIA may not be valid with respect to the values reported with DXA, with the exception of Carter's anthropometry formula for general sample and Evans's anthropometry formula for female sample. BIA could also be an alternative if what is needed is to assess fat mass in women as a group.

Obesity, Physical Performance, Balance Confidence, and Falls in Community-Dwelling Older Adults: Results from the Korean Frailty and Aging Cohort Study

Obesity affects physical functions in numerous ways. We aimed to evaluate the association between obesity and falls, physical performance, and balance confidence in community-dwelling older adults. Using first-year baseline data from the Korean Frailty and Aging Cohort Study, 979 older adults were included. General obesity was defined based on the body mass index and body fat percentage, whereas central obesity was classified based on the waist circumference and waist-to-height ratio. Data regarding fall history and balance confidence were acquired using self-questionnaires, and a timed up-and-go test was performed to measure balance-related physical performance. Overall, 17.3% of participants experienced falls in the previous year. Central obesity, as determined by waist circumference (odds ratio, 1.461; 95% confidence interval, 1.024-2.086; p-value, 0.037) and by waist-to-height ratio (odds ratio, 1.808; 95% confidence interval, 1.015-3.221; p-value, 0.044) was significantly associated with falls. Interestingly, general obesity, measured by body fat percentage, was protective against fall-related fractures (odds ratio, 0.211; 95% confidence interval, 0.072-0.615; p-value, 0.004). Participants with central obesity had poorer physical performances in the timed up-and-go test (odds ratio, 2.162; 95% confidence interval, 1.203-3.889; p-value, 0.010) and lower balance confidence according to the Activities-specific Balance Confidence scale (odds ratio, 1.681; 95% confidence interval, 1.153-2.341; p-value 0.007). In conclusion, assessment of central obesity, particularly waist circumference, should be considered as a screening strategy for falls, and older adults with a high waist circumference should receive advice on fall prevention.

Prediction of body fat percentage: Development and validation of new anthropometric equations

INTRODUCTION

The aim of this study was to test the validity of existing equations, retrieved from the literature, in the Algerian adult population. To develop, and validate, new predictive equations for body fat percentage (%BF) using simple and easy-to-measure anthropometric parameters.

METHODS

This is a cross-sectional study including 877 Algerian adults who underwent a body composition assessment by the direct segmental multi-frequency bioelectrical impedance technique (Inbody-770). Participants were randomly divided into two groups: the development group (n = 577) and the validation group (n = 300). To develop the equations, multiple linear regression models were analyzed. The predictive performance of the developed equations was compared with the direct technique. The following validation tests were used: Student's t-test for paired samples, correlation, and Bland-Altman diagram. Diagnostic accuracy has also been assessed.

RESULTS

Four existing equations were tested, and all showed statically significant bias. Four new equations were developed; all had satisfactory predictive performance, with a correlation coefficient ranging from 0.72 to 0.94 in men and 0.87 to 0.93 in women. The best-fitting equation was based on body mass index, waist-to-hip ratio, and chest circumference. The diagnostic accuracy of this equation was 96.7% in men and 95.3% in women.

CONCLUSION

The newly developed equations based on anthropometric parameters can serve as a simple tool for the accurate prediction of BF% in adult subjects, at both individual and epidemiological levels.

Examining the Systemic Bioavailability of Cannabidiol and Tetrahydrocannabinol from a Novel Transdermal Delivery System in Healthy Adults: A Single-Arm, Open-Label, Exploratory Study

INTRODUCTION

Transdermal cannabinoids may provide better safety and bioavailability profiles compared with other routes of administration. This single-arm, open-label study investigated a novel topical transdermal delivery system on the pharmacokinetics of cannabidiol (CBD) and tetrahydrocannabinol (THC).

METHODS

Participants were 39.5 ± 7.37 years old and healthy, based on a review by the Medical Director. Blood was collected pre-dose and 10, 20, 30, and 45 min, and 1, 1.5, 2, 2.5, 3, 4, 5, 6, 8, and 12 h after topical application of 100 mg CBD:100 mg THC. Psychoactive effects were assessed prior to each timepoint. Area-under-the-curve (AUC_0-12 h), maximum concentration (C_max), time to maximum concentration (T_max), area-under-the-curve to infinity (AUC_I), terminal elimination rate constant (λ), terminal half-life (t½), and absorption rate constant (k_a) were measured individually for CBD and THC. Safety was assessed by clinical chemistry, hematology, and adverse events.

RESULTS

AUC_0-12 h for CBD and THC was 3329.8 ± 3252.1 and 2093.4 ± 2090.6 pg/mL/h, with C_max of 576.52 ± 1016.18 and 346.57 ± 776.85 pg/mL, respectively. T_max for CBD and THC was 8 h, ranging from 2.5 h to 12 h and 10 min to 12 h, respectively. AUC_I for CBD and THC was 6609.2 ± 7056.4 and 3721.0 ± 3251.7 pg/mL/h, with t_1/2 of 5.68 ± 1.5 and 5.38 ± 1.25 h, respectively. CBD was absorbed at a faster rate compared with THC (123.36 ± 530.97 versus 71.5 ± 1142.19 h^-1) but with similar λ (0.12 ± 0.029 versus 0.13 ± 0.03 h^-1). No psychoactive effects were reported. Transdermal cannabinoid delivery was safe and well tolerated in the population studied.

CONCLUSION

To our knowledge, this is the first pharmacokinetic study in humans that demonstrated CBD and THC entering systemic circulation via transdermal administration . This study represents an important contribution to understanding the pharmacokinetics of transdermal cannabinoids.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov Identifier-NCT05121506 (November 16, 2021).

Comparison of Several Prediction Equations Using Skinfold Thickness for Estimating Percentage Body Fat vs. Body Fat Percentage Determined by BIA in 6-8-Year-Old South African Children: The BC-IT Study

Body composition measurement is useful for assessing percentage body fat (%BF) and medical diagnosis, monitoring disease progression and response to treatment, and is essential in assessing nutritional status, especially in children. However, finding accurate and precise techniques remains a challenge. The study compares %BF determined by bioelectrical impedance analysis (BIA) and calculated from available prediction equations based on skinfolds in young South African children. A cross-sectional study performed on 202 children (83 boys and 119 girls) aged 6-8 years. Height and weight, triceps and subscapular skinfolds were determined according to standard procedures. %BF was determined with BIA and three relevant available equations. SPSS analyzed the data using paired samples tests, linear regression, and Bland-Altman plots. Significant paired mean differences were found for BIA and Slaughter (t₂₀₁ = 33.896, p < 0.001), Wickramasinghe (t₂₀₁ = 4.217, p < 0.001), and Dezenberg (t₂₀₁ = 19.910, p < 0.001). For all of the equations, the standards for evaluating prediction errors (SEE) were above 5. The Bland-Altman plots show relatively large positive and negative deviations from the mean difference lines and trends of systematic under- and over-estimation of %BF across the %BF spectrum. All three equations demonstrated a smaller %BF than the %BF measured by BIA, but the difference was smallest with the Wickramasinghe equation. In comparison, a poor SEE was found in the three %BF predicted equations and %BF derived from BIA. As such, an age-specific %BF equation incorporating criterion methods of deuterium dilution techniques or 'gold-standard' methods is needed to refute these findings. However, in the absence of developed %BF equations or 'gold-standard' methods, the available prediction equations are still desirable.

Relationship between BMI with percentage body fat and obesity in Singaporean adults - The Yishun Study

BACKGROUND

The main aim of this study was to the determine relationship between Body Mass Index (BMI) and percentage body fat (BF%) in Singaporean adults, derive a prediction model to estimate BF%, and to report population BF%. The secondary aim was to determine the prevalence of overweight and obesity based on BF% threshold and the new risk categories for obesity in Singaporean population.

METHODS

This was a population-based study of 542 community-dwelling Singaporeans (21-90 years old, 43.1% men). Anthropometry and body composition were assessed. Relationship between BMI and BF% were analysed using multiple regression models. Prevalence of overweight and obesity were estimated using WHO and Singapore Ministry of Health (MOH) Clinical Practice Guidelines for BMI classification, and BF% cut-off points of 25 and 35% for men and women respectively.

RESULTS

We derived a prediction model to estimate BF% based on BMI, age and sex. The current cohort of Singaporeans when compared to Caucasians in the US and Europe as well as a Singapore cohort from 20 years age have higher BF% when matched for BMI, age, and sex. The overall population-adjusted prevalence of obesity according to WHO International classification (BMI ≥30 kg/m2) was 12.9% (14.9% men; 11.0% women); and 26.6% (30.7% men; 22.8% women) according to the MOH classification (BMI ≥27.5 kg/m2). However, using the BF% cut-off (> 25% for men and > 35% for women) resulted in very high prevalence of obesity of 82.0% (80.2% men; 83.8% women).

CONCLUSION

There is a large discrepancy between BF% and BMI measured obesity in Singaporean adults. The results confirmed that Singaporean adults have higher BF% at lower BMI compared to US and Europe white counterparts; and that BF% in our population has increased over two decades.

Exploring the relationship between health concerns and high-risk behaviours in Medical Sciences' students

Aim

The need to cope with life concerns may drive an individual to resort to high‐risk behaviours. This study aimed to determine the relationship between health concerns and high‐risk behaviours.

Design

A cross‐sectional study.

Methods

We sampled 926 Medical Sciences' students from the North of Iran from September–December 2017 using the stratified sampling method.

Results

The most and less common high‐risk behaviour was physical inactivity (97.5%) and high‐risk sexual behaviour (15.7%), respectively. In multivariate logistic regression analysis, participants' concerns about human sexuality (AOR: 1.39; CI: 1.22, 1.57), injury prevention and control (AOR: 1.12; CI: 1.01, 1.20), nutrition (AOR: 1.13; CI: 1.02, 1.26) and emotional health (AOR: 1.08; CI: 1.02, 1.15) increased the odds of risky behaviours. Among Medical Sciences' students, health concerns are linked with risky behaviours. The result of this study can be used to develop relevant interventions targeting mental health to reduce risky behaviour among youth.

Comparison of anthropometric-based equations for estimation of body fat percentage in a normal-weight and overweight female cohort: validation via air-displacement plethysmography

OBJECTIVE

To evaluate the accuracy of the most commonly used anthropometric-based equations in the estimation of percentage body fat (%BF) in both normal-weight and overweight women using air-displacement plethysmography (ADP) as the criterion measure.

DESIGN

A comparative study in which the equations of Durnin and Womersley (1974; DW) and Jackson, Pollock and Ward (1980) at three, four and seven sites (JPW₃, JPW₄ and JPW₇) were validated against ADP in three groups. Group 1 included all participants, group 2 included participants with a BMI <25·0 kg/m² and group 3 included participants with a BMI ≥25·0 kg/m².

SETTING

Human Performance Laboratory, Institute for Sport and Health, University College Dublin, Republic of Ireland.

SUBJECTS

Forty-three female participants aged between 18 and 55 years.

RESULTS

In all three groups, the %BF values estimated from the DW equation were closer to the criterion measure (i.e. ADP) than those estimated from the other equations. Of the three JPW equations, JPW₃ provided the most accurate estimation of %BF when compared with ADP in all three groups.

CONCLUSION

In comparison to ADP, these findings suggest that the DW equation is the most accurate anthropometric method for the estimation of %BF in both normal-weight and overweight females.

Body Composition and Abdominal Obesity in Patients With and Without Coronary Heart Disease

Background

The body fat and its distribution is an important risk factor for coronary artery diseases. The aim of this study was to evaluate the relationship between body composition and abdominal obesity in patients with and without coronary involvement in stable angina.

Methods

One hundred and sixty-one patients who underwent coronary angiography for stable angina were divided into two groups: patients with or without coronary heart disease (CHD). Participants underwent bioimpedance analysis for measurement of adipose tissues and lean body mass.

Results

No significant difference in body mass index and weight was found between two groups. Mean levels of waist circumference, waist to hip ratio and fat mass were significantly higher in CHD group (P = 0.02, P = 0.04 and P = 0.01). Fat-free mass was also significantly higher in non-CHD group (P = 0.02).

Conclusions

Screening for adiposity in subjects by body composition measurement method and determining fat distribution could better identify those at higher risk for CHD.

Determination of the most influential sources of variability in tacrolimus trough blood concentrations in adult liver transplant recipients: a bottom-up approach

Tacrolimus, an immunosuppressant drug, presents a narrow therapeutic window and a large pharmacokinetic variability with poor correlation between drug dosing regimen and blood concentration. The objective was to identify predictive factors influencing tacrolimus trough concentrations (C0) using a bottom-up approach. A physiologically based pharmacokinetic (PBPK) model of tacrolimus was proposed, taking into account the body weight, the proportion of fat (P(fat)), hematocrit, lipid fraction of organs, typical intrinsic clearance (CLi(typ)), CYP3A5 genotype of liver donor, plasma unbound fraction of tacrolimus (fu(p)), and concomitant drugs (CYP3A4 inhibitors). For the evaluation of the PBPK model, mean C0 and concentrations 2 h after oral dose of tacrolimus were compared with those from 66 liver transplant recipients included in a multicentric pharmacokinetic study and were found very close. Tacrolimus concentration profiles were simulated in a virtual population defined by a set of covariate values similar to those from the real population. The sensitivity of tacrolimus C0 with respect to each covariate has been tested to identify the most influential ones. With the range of covariate values tested, the impact of each covariate on tacrolimus C0 may be ranked as follows: fu(p), CLi(typ), bioavailability, body weight, hematocrit, CYP3A5 polymorphism, P(fat), and CYP3A4 inhibitory drug-drug interactions. Values for initial dosing regimen of tacrolimus in order to reach a C0 of 10 ng/ml at day 5 (assuming a constant dosing schedule) as a function of CYP3A5 donor genotype and patient's hematocrit and body weight are proposed.

Predicting body fat percentage based on gender, age and BMI by using artificial neural networks

In the human body, the relation between fat and fat-free mass (muscles, bones etc.) is necessary for the diagnosis of obesity and prediction of its comorbidities. Numerous formulas, such as Deurenberg et al., Gallagher et al., Jackson and Pollock, Jackson et al. etc., are available to predict body fat percentage (BF%) from gender (GEN), age (AGE) and body mass index (BMI). These formulas are all fairly similar and widely applicable, since they provide an easy, low-cost and non-invasive prediction of BF%. This paper presents a program solution for predicting BF% based on artificial neural network (ANN). ANN training, validation and testing are done by randomly divided dataset that includes 2755 subjects: 1332 women (GEN = 0) and 1423 men (GEN = 1), with AGE from 18 to 88 y and BMI from 16.60 to 64.60 kg/m(2). BF% was estimated by using Tanita bioelectrical impedance measurements (Tanita Corporation, Tokyo, Japan). ANN inputs are: GEN, AGE and BMI, and output is BF%. The predictive accuracy of our solution is 80.43%. The main goal of this paper is to promote a new approach to predicting BF% that has same complexity and costs but higher predictive accuracy than above-mentioned formulas.

Optimal body fat percentage cut-offs for obesity in Chinese adults

Obesity results in an increased risk of metabolic syndrome (MetS) and Type 2 diabetes (T2DM). Body fat percentage (BF%) is a common index of body composition. The aim of the present study was to determine the optimal BF% cut-offs for obesity to predict MetS and T2DM in Chinese adults. The baseline study group comprised 3916 Chinese adults (age 30-70 years of age); 2033 subjects without MetS or T2DM were followed up for a maximum of 5.5 years. The BF% was estimated using bioelectrical impedance analysis. Optimal BF% cut-offs were analysed by receiver operating characteristic (ROC) curves. Binary logistic regression analysis was performed to measure the association between obesity at baseline defined by BF% and newly developed MetS and T2DM. Mean BF% levels were lower in men than in women (23.9 ± 6.1% vs 33.5 ± 7.1%, respectively; P < 0.01). For men, the optimal BF% cut-offs for the prediction of MetS and T2DM were 25.45% and 26.65%, respectively; for women, the corresponding values were 34.95% and 36.55%. Subjects with high BF% (≥ 25% in men; ≥ 35% in women) had higher risks of incident MetS or T2DM than those with low BF% (< 25% in men; < 35% in women). The relative risks were 3.43 (95% confidence intervals (CI) 2.59-4.54) and 2.92 (95% CI 1.85-4.60), respectively. The optimal BF% cut-offs for obesity for the prediction of MetS and T2DM in Chinese men and women were around 25% and 35%, respectively.

Correlation between body composition and risk factors for cardiovascular disease and metabolic syndrome

Body mass index (BMI) is an important diagnostic tool for determining obesity; however, while BMI reflects the influence of body height over body weight, it does not reveal body fat percentage (BF%). We explored whether BF% correlated with risk factors for cardiovascular disease and metabolic syndrome and whether metabolically obese, normal weight people were at risk for these diseases. A total of 2,867 healthy volunteers participated in this study. Blood pressure, height, weight, waist circumference, BMI, BF%, lipid profile, fasting glucose, uric acid, and lifestyle factors were collected from healthy subjects during their annual health examinations. In both males and females, BF% correlated positively with BMI and waist circumference. Participants were divided into three groups according to BF% and data were compared between groups. The results suggest that BF% correlates with risk factors for cardiovascular disease and metabolic syndrome for both men and women, and that BF% may be a useful predictor of risk, particularly in metabolically obese, normal weight individuals.

Accuracy of Siri and Brozek equations in the percent body fat estimation in older adults

OBJECTIVE

To identify which equation, Siri or Brozek, based on the two compartment model, provides a more accurate conversion of body density (BD) in percent body fat (%BF) in a group of older adults.

STUDY DESIGN

Cross-sectional study.

SETTING

Research Centre in Physical Activity, Health and Leisure, Faculty of Sport, University of Porto.

PARTICIPANTS

60 older adults, aged 60-92 years.

MEASUREMENTS

Skinfold thickness was used to estimate BD through Visser et al. prediction equation. The conversion of BD to %BF was done with Siri (%BF-Siri) and Brozek (%BF-Brozek) formulas and these determined values were both compared to Dual-Energy X-ray Absorptiometry (%BF-DXA) evaluations.

RESULTS

A strong correlation between the %BF-DXA value and %BF-Siri (r=0.91, p < 0.001) and %BF-Brozek (r=0.91, p < 0.001) was found, although %BF-Siri and %BF-Brozek overestimated %BF-DXA (p < 0.001). The comparison of the %BF-Siri and %BF-Brozek mean values also revealed significant differences (p < 0.001). The %BF-Brozek reflects a better agreement than the %BF-Siri with %BF-DXA with respectively a mean difference of -4.0 %BF (limits of agreement = -10.9 to 2.9%) and -5.7 %BF (-12.6 to 1.2). The Bland and Altman plots confirmed that %BF-Brozek reflects a better agreement with %BF-DXA.

CONCLUSION

The results of the present study show that the use of Brozek equation may correspond to a more accurate alternative than Siri equation for the conversion of BD in %BF in older adults.

Normalized bioimpedance indices are better predictors of outcome in peritoneal dialysis patients

BACKGROUND

While phase angle of bioimpedance analysis (BIA) has great survival-predicting value in dialysis populations, it is known to be higher in male than in female subjects. In this study, we aimed to explore the factors influencing the predictive value of phase angle and to identify the appropriate physics terms for normalizing capacitance (C) and resistance (R).

METHODS

We formulated body capacitive index (BCI), C(BMI) (capacitance × height(2)/weight), body resistive index (BRI), R(BMI) (resistance × weight/height(2)), and CH(2) (capacitance × height(2)). We also studied H(2)/R, R/H, and reactance of a capacitor/height (X(C) /H). There are 3 components in this study design: (1) establishment of normal values in a control Malaysian population, (2) comparison of these with a CAPD population, and (3) prediction of survival within a CAPD population. We initially performed a BIA study in 206 female and 116 male healthy volunteers, followed by a prospective study in a cohort of 128 CAPD patients [47 with diabetes mellitus (DM), 81 non-DM; 59 males, 69 females] for at least 2 years. All the parameters during enrolment, including BIA, serum albumin, peritoneal equilibrium test, age, and DM status, were analyzed. Outcome measurement was survival.

RESULTS

In healthy volunteers, both genders had the same BCI (2.0 nF kg/m(2)). On the contrary, female normal subjects had higher BRI than male normal subjects (median 15 642 vs 13242 Ω kg/m(2), p < 0.001) due to higher fat percentage (35.4% ± 0.4% vs 28.0% ± 0.6%, p < 0.001), resulting in a lower phase angle (mean 5.82 ± 0.04 vs 6.86 ± 0.07 degrees, p < 0.001). Logistic regression showed that BCI was the best risk indicator in 128 CAPD patients versus 322 normal subjects. In age- and body mass index (BMI)-matched head-to-head comparison, BCI had the highest χ(2) value (χ(2) = 102.63), followed by CH(2) (or H(2)/X(C); χ(2) = 81.00), BRI (χ(2) = 20.54), and X(C)/H (χ(2) = 20.48), with p value < 0.001 for these parameters. In comparison, phase angle (χ(2) = 11.42), R/H (χ(2) = 7.19), and H(2)/R (χ(2) = 5.69) had lower χ(2) values. 35 (27.3%) patients died during the study period. Univariate analysis adjusted for DM status and serum albumin level demonstrated that non-surviving patients had significantly higher CH(2) (245 vs 169 nF m(2), p < 0.001) and BCI (4.0 vs 2.9 nF m(2)/kg, p = 0.005) than patients that survived. CH(2) was the best predictor for all-cause mortality in Cox regression analysis, followed by BCI, phase angle, and X(C)/H.

CONCLUSION

Measures that normalize, such as BCI and CH(2), have higher risk discrimination and survival prediction ability than measures that do not normalize, such as phase angle. Unlike phase angle, measurement of BCI overcomes the gender effect. In this study, the best risk indicator for CAPD patients versus the general population is BCI, reflecting deficit in nutritional concentration, while CH(2) reflects total nutritional deficit and thus is the major risk indicator for survival of CAPD patients.

Comparison of body mass index with body fat percentage in the evaluation of obesity in Chinese

OBJECTIVE

To evaluate the present Chinese body mass index (BMI) criteria with body fat percentage (BF%) in determining obesity in Chinese population.

METHODS

A total of 4 907 subjects (age: 20-90 yrs) were enrolled in the baseline survey of a longitudinal epidemiological study, and 2 638 of them were reevaluated in 5.5 years later. The Chinese BMI and WHO BF% were used to define obesity, respectively.

RESULTS

The diagnostic agreement between the Chinese BMI and WHO BF% definitions for obesity was poor for both men (kappa: 0.210, 95% CI: 0.179-0.241) and women (kappa: 0.327, 95% CI: 0.296-0.358). However, BMI had a good correlation with BF% both in men (r: 0.785, P<0.01) and women (r: 0.864, P<0.01). The age and sex-adjusted relative risks (RR) for incidence of type 2 diabetes (T2DM) were significantly higher in subjects with intermediate BF% (BF%:20.1%-25% for men, 30.1%-35% for women) (RR: 2.35, 95% CI: 1.23-4.48) and high BF%(BF%>25% for men and > 35% for women)(RR: 2.89, 95% CI: 1.43-5.81), or in subjects with high BMI (BMI>or=28 kg/m(2)) (RR: 2.46, 95% CI: 1.31-4.63) when compared to those with low BF% (BF%<or=20% for men and<or=30% for women) or low BMI (BMI24 kg/m(2)) respectively. No difference in risk could be found in those with intermediate BMI (BMI: 24-27.9 kg/m(2)) (RR: 1.44, 95% CI: 0.86-2.40), as compared to those with low BMI (BMI<24 kg/m(2)), whose BF% ranged widely from 7.8 to 50.3%.

CONCLUSION

BMI was correlated with BF%. Both BMI and BF% were associated with high risk for T2DM. However, BMI had its limitations in the interpretation of subjects with BMI between 24 and 27.9 kg/m(2).

Comparative effects of continuous combined hormone therapy and tibolone on body composition in postmenopausal women

OBJECTIVE

To compare the effects of tibolone with those of continuous combined hormone replacement therapy (HT) on body composition in postmenopausal women.

METHODS

One hundred and fifty postmenopausal women were enrolled in a randomized, controlled trial to compare the effects of tibolone with continuous combined HT on body composition. Patients were randomly allocated into three groups and followed for 9 months. Of the subjects included, 50 women received 2.5 mg tibolone plus one Cal+D tablet (500 mg calcium and 200 IU vitamin D) daily, 50 women received 0.625 mg conjugated equine estrogen and 2.5 mg medroxyprogesterone acetate (CEE/MPA) plus one Cal+D tablet daily, and the rest (50 women) received only one Cal+D tablet and served as a control group. Body composition was evaluated with measurements of body mass index (BMI), weight, waist-to-hip ratio (WHR), fat mass and fat-free mass (FFM) before and after the intervention. Measurements of body fat mass percentage, fat mass, body fat-free mass percentage and fat-free mass (FFM) were assessed by measurement of skin-fold thickness.

RESULTS

Tibolone significantly increased weight, BMI and FFM and decreased WHR after the treatment in comparison with baseline (p < 0.05). However, only weight and BMI increased significantly in the CEE/MPA group after the treatment (p < 0.05). There were significant increases in weight, BMI and fat mass in the control group after 9 months. In the comparison of the parameters after the treatment between the three groups, tibolone significantly increased FFM compared with the control and CEE/MPA groups (p < 0.01).

CONCLUSIONS

The effect of tibolone on body composition is favorable and therefore tibolone may be regarded as an alternative to continuous combined hormone therapy in postmenopausal women.

Obesity indices in relation to cardiovascular disease risk factors among young adult female students

The objective of the present study was to compare the percentage of body fat (%BF), BMI, and central fat distribution anthropometric measures as indices of obesity and to assess the respective associations with cardiovascular risk factors in young female students. Subjects were 220 healthy Greek female students. Dual-energy X-ray absorptiometry was used to estimate %BF, anthropometric measurements were obtained and blood samples were analysed for CVD risk factors. Results showed that 48·6 % of students had increased adiposity, while a considerable proportion was characterised by central fat distribution irrespective of the anthropometric index used. The proportion of subjects with at least one metabolic risk factor present was 60·4 %. Although %BF was not associated with any of the CVD risk factors, waist circumference, waist:hip ratio and waist:height ratio were all associated with CVD risk factors. Higher levels of these anthropometric variables demonstrated higher prevalence of CVD risk factors. The lack of association between %BF and CVD risk factors could be attributed to the fact that females with undesirable adiposity had a tendency for the gynaecoid type of obesity. In contrast, the present results suggest that central body fat distribution in young women may reflect increased risk due to high visceral and particularly intra-abdominal fat levels. Recent epidemiological data from Greece show a high prevalence of overweight and obesity in young adults. Therefore, assessing the risk for the presence of CVD risk factors is of particular importance. Central obesity anthropometric indices seem to be valuable screening tools for young women.

Prevalence of overweight, obesity and physical inactivity in 20- to 29-year-old, Danish men. Relation to sociodemography, physical dysfunction and low socioeconomic status: the Odense Androgen Study

OBJECTIVE

To assess the prevalence of overweight, obesity and physical inactivity in 20- to 29-year-old men and to analyze whether sociodemography, physical dysfunction and low socioeconomic status are independent correlates of obesity and physical inactivity.

DESIGN

Population-based, cross-sectional study.

SUBJECTS

Seven hundred and eighty-three Caucasian, Danish men, aged 20-29 years recruited from 2042 respondents in a questionnaire survey of 3000 men, randomly drawn from the Danish Civil Registration System.

METHODS

Questionnaire, interview and physical examination.

RESULTS

The 783 included men and the 2042 questionnaire respondents matched the background population demographically. The 783 men matched the questionnaire respondents as regards BMI, physical activity, chronic disease, medication, smoking, sociodemography and socioeconomic status. The prevalence of overweight and obesity was 31.7 and 7.9%, respectively (World Health Organization criteria). Using waist circumference (WC) cutoffs of 94 and 102 cm, the prevalence was 16.2 and 10.6%, respectively; 24.4% were physically inactive. BMI and WC increased significantly from age 20 to 29 years. Physical activity decreased significantly with age and correlated inversely with WC, but not with BMI. Occupation, geography, partner status, fatherhood and tobacco exposure were independently related with obesity and physical inactivity. Obesity was also related to musculoskeletal complaints, whereas chronic diseases and low educational level were associated with physical inactivity. Age was not independently related with either outcome.

CONCLUSION

In affluent societies, sociodemographic changes may partly explain the age-related decrease in physical activity and the parallel increase in WC and BMI.