Ability of different measures of adiposity to identify high metabolic risk in adolescents

Adherence to a Mediterranean Diet, Body Composition and Energy Expenditure in Outpatients Adolescents Diagnosed with Anorexia Nervosa: A Pilot Study

Weight restoration is the primary goal of treatment for patients with Anorexia Nervosa (AN). This observational pilot study aims to describe adherence to the Mediterranean Diet (MD) and the consequent process of weight and functional recovery in outpatient adolescents diagnosed with AN. Eight patients with a median age of 15.1 (14.0-17.1) years were seen at baseline and after six months. Anthropometrics, body composition, and resting energy expenditure (REE) were assessed. The KIDMED questionnaire, the 24 h recall, and a quantitative food frequency questionnaire were used to evaluate adherence to the MD. The median KIDMED score increased from 5.5 (T0) to 10 (T1), which was not significant. Intakes of grams of carbohydrates, lipids, mono-unsaturated fatty acids, and fiber increased (p = 0.012, p = 0.036, p = 0.036, p = 0.025). Weight significantly increased (p = 0.012) as well as lean body mass (p = 0.036), with a resulting improvement of the REE (p = 0.012). No association between anthropometrics and body composition and the KIDMED score was found. The MD could represent an optimal dietary pattern for weight gain and nutritional restoration in patients with AN, and it could lead to an improvement in body composition and resting energy expenditure.

Accuracy of different cutoffs of the waist-to-height ratio as a screening tool for cardiometabolic risk in children and adolescents: A systematic review and meta-analysis of diagnostic test accuracy studies

The present systematic review with meta-analysis sought to estimate the accuracy of different waist-to-height ratio (WHtR) cutoff ranges as risk indicators for cardiometabolic health in different populations of children and adolescents. Systematic searches were undertaken to identify studies in apparently healthy participants aged 3-18 years that conducted receiver operating characteristic curve analysis and reported area under the receiver operating characteristic curves for WHtR with any cardiometabolic biomarker. Forty-one cross-sectional studies were included in the meta-analysis, including 138,561 young individuals (50% girls). Higher area under summary receiver operating characteristic (AUSROC) values were observed in cutoffs between 0.46 and 0.50 (AUSROC = 0.83, 95%CI: 0.80-0.86) and ≥0.51 (AUSROC = 0.87, 95%CI: 0.84-0.90) (p < 0.001 in comparison with cutoffs 0.41 to 0.45), with similar results in both sexes. The AUSROC value increased in the East and Southeast Asian regions using a WHtR cutoff of ≥0.46 (AUSROC = 0.90, 95%CI: 0.87 to 0.92). A cutoff of ≥0.54 was optimal for the Latin American region (AUSROC = 0.96, 95%CI: 0.94-0.97). Our meta-analysis identified optimal cutoff values of WHtR for use in children and adolescents from different regions. Despite the widely accepted WHtR cutoff of 0.50, the present study indicated that a single cutoff value of WHtR may be inappropriate.

Waist-to-Height Ratio Is a Good Predictor of Metabolic Syndrome in Adolescents: A Report From the Thai National Health Examination Survey V, 2014

This study aimed to assess the performance of waist-to-height ratio (WHtR) in the prediction of metabolic syndrome and to determine the appropriate cutoff value in Thai adolescents. Demographic data, blood pressure, fasting blood glucose, and lipid profile were obtained from the Thai National Health Examination Survey V database. The performances of WHtR, waist circumference, body mass index (BMI), and BMI z-score were analyzed by the receiver operating characteristics. Among 2644 adolescents, metabolic syndrome was identified in 4.27%. The areas under the receiver operating characteristic curves of WHtR, waist circumference, BMI, and BMI z-score were comparable (0.924-0.960). Performance of WHtR was more constant across age groups compared with other parameters. Using the cutoff value of WHtR at 0.5 resulted in the sensitivity and specificity of 98.5%/83.4% and 88.9%/86.0% in males and females, respectively. In conclusion, the cutoff value of WHtR at 0.5 provided good sensitivity and specificity for identifying metabolic syndrome in both genders. However, the other clinical risk factors or more definite scores should be considered when further assessment.

Waist-to-height ratio as a risk marker for metabolic syndrome in childhood. A meta-analysis

BACKGROUND

Individuals with abdominal obesity have a higher cardiovascular risk, regardless of the degree of global overweight.

OBJECTIVE

To estimate the accuracy of the Waist/height ratio (WtHR) as a risk marker for metabolic syndrome (MS) in children or adolescents.

METHODS

Published cohort or cross-sectional studies (Pubmed, Embase-SCOPUS and CINAHL) were searched, with no limits of time. Studies providing Waist/height ratio and clustered criteria of metabolic syndrome were included.

RESULTS

Thirty-one studies (66,912 subjects) were selected. Overall, a high WtHR (≥0.5) was associated with a four-fold increased risk of clustered criteria of MS (odds ratio [OR] 4.15, 95% confidence interval [95% CI]: 2.69 to 6.42) and two-fold increased risk when adjusted by general obesity (adjusted OR 2.26, 95% CI: 1.29 to 3.98). The WtHR, as a quantitative measure, showed a pooled area under the curve of 0.76 (95% CI: 0.71 to 0.80) and, as a dichotomous measure, with a cut-off point close to 0.5, a sensitivity of 60% (95% CI: 50% to 68.8%) and a specificity of 79% (95% CI: 71.6% to 83.9%).

CONCLUSIONS

Measuring WtHR may be considered in regular health checks of children and adolescents, as it can measure cardiovascular risk regardless of the degree of general obesity.

Comparing measures of general and abdominal adiposity as predictors of blood pressure in college students

OBJECTIVE

To compare anthropometric measures of body mass index (BMI), waist circumference (WC), waist-to-height ratio (WHtR), and sagittal abdominal diameter (SAD) as predictors of blood pressure in college students.

PARTICIPANTS

Students (N = 116) were recruited from November 2012 to May 2014 at an urban university and rural community colleges.

METHODS

Students underwent a brief physical examination during which anthropometric measures were obtained and blood pressure was measured. Covariates were measured using self-reported questionnaires. Hierarchical multiple linear regressions were used for the data analysis.

RESULTS

All anthropometric measures were predictive of systolic (SBP) and diastolic blood pressure (DBP). WC was the strongest predictor of SBP (β = .582, p < .01) explaining an additional 3-4% of the variance than BMI, WHtR, or SAD. The measures were similar in predicting DBP. WC predicted SBP independent of BMI.

CONCLUSIONS

Clinicians should consider using WC to assess the risk for hypertension in college students.

Waist-to-height ratio, body mass index and waist circumference for screening paediatric cardio-metabolic risk factors: a meta-analysis

Waist-to-height ratio (WHtR) is superior to body mass index and waist circumference for measuring adult cardio-metabolic risk factors. However, there is no meta-analysis to evaluate its discriminatory power in children and adolescents. A meta-analysis was conducted using multiple databases, including Embase and Medline. Studies were included that utilized receiver-operating characteristics curve analysis and published area under the receiver-operating characteristics curves (AUC) for adiposity indicators with hyperglycaemia, elevated blood pressure, dyslipidemia, metabolic syndrome and other cardio-metabolic outcomes. Thirty-four studies met the inclusion criteria. AUC values were extracted and pooled using a random-effects model and were weighted using the inverse variance method. The mean AUC values for each index were greater than 0.6 for most outcomes including hypertension. The values were the highest when screening for metabolic syndrome (AUC > 0.8). WHtR did not have significantly better screening power than other two indexes in most outcomes, except for elevated triglycerides when compared with body mass index and high metabolic risk score when compared with waist circumference. Although not being superior in discriminatory power, WHtR is convenient in terms of measurement and interpretation, which is advantageous in practice and allows for the quick identification of children with cardio-metabolic risk factors at an early age.

Male Sexual Dysfunction, Leptin, Pituitary and Gonadal Hormones in Nigerian Males with Metabolic Syndrome and Type 2 Diabetes Mellitus

BACKGROUND

Pituitary and gonadal dysfunctions resulting from increased adiposity leading to disturbances of sexual and reproductive functions have been reported in males with metabolic syndrome (MS) and type 2 diabetes mellitus (DM2). The aim of this study was to evaluate sexual dysfunction, leptin, and reproductive hormones in Nigerian males with MS and DM2.

METHODS

Participants were 104 men (34 males with DM2, 17 men with MS and 53 men with normal body mass index (18.5-24.9 Kg/m (2)) without MS (controls)). The International Diabetes Federation (2005) criteria were used for MS diagnosis. Reproductive history, anthropometry, blood pressure (BP) and 10 ml fasting blood samples were obtained by standard methods. Fasting plasma glucose, total cholesterol, triglycerides and high density lipoprotein cholesterol were determined by enzymatic methods while low density lipoprotein cholesterol was calculated. Leptin, follicle stimulating hormone (FSH), luteinising hormone (LH), prolactin, testosterone and oestrogen were determined by enzyme immunoassay (leptin by Diagnostic Automation, Inc.; others by Immunometrics (UK) Ltd.) while oestrogen-testosterone ratio was calculated. Data analyzed using ANOVA, Chi square and multiple regression were statistically significant at p<0.05.

RESULTS

Testosterone was significantly lower in MS than controls while oestradiol and ETR were significantly higher in MS compared with controls and DM2 group (p<0.05). ETR significantly predicted testosterone in all groups (p<0.05). Significantly lower libido was observed in men in MS than controls and DM2 groups (p<0.05).

CONCLUSION

Sexual and reproductive dysfunction may be related to increased conversion of testosterone to oestrogen in increased adipose mass in men with metabolic syndrome and type 2 diabetes mellitus.

The association between cardiovascular disease risk and parental educational level in Portuguese children

The aim of this study was to examine any differences in cardiovascular disease (CVD) risk in Portuguese children split by parental educational level. A cross-sectional school-based study was conducted in 2011 on 359 Portuguese children (202 girls and 157 boys) aged 10 to 17 years (mean age ± SD = 13.9 ± 1.98 years). Height and body mass were assessed to determine body mass index (BMI). Parental education level (PEL) was used as a surrogate for socioeconomic status (SES). Capillary blood sampling was used to determine: Total Cholesterol (TC), Triglycerides (TG), Fasting Glucos (GLUC), High and Low Density Lipoprotein (HDL/LDL). These measurements were combined with measures of systolic blood pressure and cardiorespiratory fitness as z-scores. CVD risk was constructed by summing the z-scores. Analysis of covariance, controlling for BMI, indicated that CVD risk was significantly different across PEL groups (p = 0.01), with CVD risk score being significantly lower in low (p = 0.04) and middle (p = 0.008) PEL groups, compared to high PEL. Moreover, the covariate, BMI was also significant (p = 0.0001, β = 0.023), evidencing a significant positive association between BMI and CVD risk, with higher BMI associated with greater CVD risk. In Portuguese children, significantly greater CVD risk was found for children of high PEL, while higher BMI was associated with greater CVD risk.

Accuracy of anthropometric measurements in estimating fat mass in individuals with 21-hydroxylase deficiency

OBJECTIVE

The use of anthropometric measurements to estimate the percentage of body fat (%BF) is easy and inexpensive. However, the accuracy of these methods in patients with 21-hydroxylase deficiency (21OHD) has not been explored. The objective of this study was to evaluate the accuracy of skinfold-based models, body mass index (BMI), and waist circumference (WC) in estimations of %BF using dual-energy X-ray absorptiometry (DXA) as the reference method in individuals with 21OHD.

METHODS

Fifty-four 21OHD patients (32 women and 22 men), aged 7 to 20 y, were recruited for the study. DXA was used to determine %BF; four predictive skinfold equations, BMI, and WC were assessed for accuracy in determining %BF.

RESULTS

All predictive skinfold equations were highly associated (R, range: 0.82-0.89) with DXA %BF values. In women, BMI and WC showed moderate correlations (R = 0.69 for both BMI and WC) with DXA values. In contrast, among men there was a low explanatory power for BMI (13%) and WC (4%) and high errors (BMI, 6.9%; WC, 7.4%). All predictive equations significantly underestimated %BF (range of differences, -4.1 to -8.9) compared with DXA (women, 31.3 ± 6.1; men, 24.4 ± 7.3), and large limits of agreement were observed (range, -15.3 to 1.7 and -15.5 to 4.2 for women and men, respectively).

CONCLUSION

In children and adolescents with 21OHD, %BF as estimated by skinfold measurements was associated more strongly with DXA-assessed %BF than both BMI and WC. However, still, the skinfold-based assessment underestimated DXA %BF and showed moderate agreement.

Comparisons between inverted body mass index and body mass index as proxies for body fatness and risk factors for metabolic risk and cardiorespiratory fitness in Portuguese adolescents

OBJECTIVES

To compare inverted body mass index (iBMI, cm(2) /kg) and body mass index (BMI, kg/m(2) ) as predictors of body fatness, metabolic risk, and cardiovascular fitness in adolescents.

METHODS

A cross-sectional school-based study was conducted on 445 Portuguese adolescents (252 girls and 193 boys) aged 10-17 years. Height and body mass were assessed to determine iBMI and BMI, percent body fatness was determined from skinfold measures (tricep, subscapular) using the Slaughter et al. (1988: Hum Biol 60: 709-723) regression equation and cardiorespiratory fitness (CRF) was assessed using the 20-m shuttle run test. Capillary blood sampling was used to determine: Total cholesterol, triglycerides, high, and low density lipoprotein. These were combined with measures of systolic blood pressure and waist circumference as z-scores. Metabolic risk (MRS) was constructed by summing the z-scores.

RESULTS

iBMI and BMI were both significantly related to percent body fatness, CRF and MRS (all P = 0.005 or better). BMI was not normally distributed (P = 0.0001), whereas iBMI was (P > 0.05). Regression analysis identified that iBMI and BMI, both alongside for age, were significant predictors of percent body fatness, CRF and MRS (all P = 0.005 or better). Compared with BMI, iBMI was a similar predictor of CRF, MRS and body fatness.

CONCLUSIONS

iBMI offers a biologically sound alternative to BMI to assess the effect of weight status on MRS and CRF in adolescents and allows appropriate use of parametrical statistical techniques without changing the conclusions drawn from such data.

Disponibilidade domiciliar de lipídeos para consumo e sua relação com os lipídeos séricos de adolescentes

OBJETIVO: Relacionar a disponibilidade domiciliar de lipídeos para consumo e o perfil lipídico sérico de adolescentes. MÉTODOS: Estudo transversal observacional. Avaliaram-se 95 adolescentes púberes de 10 a 13 anos de escolas públicas em Viçosa, Minas Gerais. Utilizou-se uma lista de compras mensal para avaliar a disponibilidade de alimentos per capita. Coletou-se amostra de sangue dos adolescentes, adotando-se o preconizado pela Sociedade Brasileira de Cardiologia como referência para adequação do perfil lipídico. Para as variáveis categóricas realizou-se o teste do qui-quadrado e calculou-se a Odds Ratio. Para comparar os grupos, aplicaram-se os testes Mann-Whitney ou t de Student, Kruskall-Wallis ou ANOVA. Verificou-se relação entre exames bioquímicos e disponibilidade de lipídeos pelas correlações de Spearmam ou de Pearson. RESULTADOS: Da energia total disponível, 27,2% foram provenientes de lipídeos. A disponibilidade de ácidos graxos saturados, monoinsaturados e poli-insaturados esteve de acordo com a recomendação de consumo. Em relação aos lipídeos séricos, 51,9% dos meninos e 55,8% das meninas apresentaram alterações de colesterol total (p=0,66); 18,6 e 25,6%, dos meninos e das meninas, respectivamente, apresentaram elevação de triglicerídeos, (meninas>meninos; p=0,02). Em relação ao LDL, 21,2 e 32,6% dos meninos e das meninas, respectivamente, apresentaram alterações (p=0,91). A prevalência de inadequação para HDL foi de 26,9 e 30,2% (p=0,93), para meninos e meninas, respectivamente. Não houve correlação entre os lipídeos disponíveis para consumo e os lipídeos séricos. Os adolescentes que possuíam mais que 35% de lipídeos disponíveis para consumo tiveram 9,1 vezes mais chances de apresentarem alterações de colesterol total (IC95% 1,81-61,74). CONCLUSÕES: É possível que adolescentes com maior disponibilidade de lipídeos para consumo apresentem colesterol total mais elevado.