Anthropometric measures of abdominal adiposity for the identification of cardiometabolic risk factors in adolescents

Association of BMI and WC for insulin resistance and type 2 diabetes among Brazilian adolescents

OBJECTIVE

To investigate how body mass index (BMI) and waist circumference (WC) may be associated with insulin resistance and type 2 diabetes (T2DM) in Brazilian adolescents.

METHODS

Cross-sectional study using data from the Brazilian Study of Cardiovascular Risks in Adolescents (ERICA) including adolescents aged 12-17 years. The relationship between adiposity and T2DM was investigated using ordinal logistic regression models. To study the association between adiposity categories and the occurrence of insulin resistance, linear regression models were used.

RESULTS

The prevalence of T2DM for the same BMI category did not increase with the presence of high WC. Regarding insulin resistance, for the same BMI categories, having a high WC resulted in a higher prevalence of insulin resistance (HOMA-IR). The only groups significantly associated with prediabetes and T2DM were those with obesity by BMI with elevated WC (POR 1.68, 95 % CI 1.45; 1.94) and obesity with normal WC (POR 1.58, 95 % CI 1.01; 2.46). Similar findings were observed concerning insulin resistance, where the increased WC had its greatest effect when associated with obesity by BMI (β Coefficient 2.20, 95 % CI 1.89; 2.50).

CONCLUSION

The combination of BMI and WC is better for assessing adolescents at risk of developing T2DM.

The association of sagittal abdominal diameter with metabolic syndrome risk before and after weight-loss surgery in adolescents

BACKGROUND

Metabolic syndrome (MetS) affects ∼10% of U.S. adolescents. Abdominal obesity is the most prevalent component and may indicate MetS risk in adolescents undergoing weight loss surgery.

OBJECTIVES

Assess MetS risk/severity and its association with abdominal obesity (measured by sagittal abdominal diameter, SAD) before and after weight loss surgery in adolescents to determine whether SAD predicts MetS risk in this population.

SETTING

Data were collected in the Teen Longitudinal Assessment of Bariatric Surgery (Teen-LABS) study at 5 sites (U.S. children's hospitals) performing weight-loss surgery in adolescents. The current study is a secondary analysis of these data.

METHODS

We examined data collected presurgery through 5 years postsurgery. MetS risk/severity was defined using the MetS severity z score (MetS-z), and MetS prevalence was determined using age-appropriate criteria. Association between SAD and MetS-z was evaluated with an adjusted linear mixed model.

RESULTS

Among 228 individuals (75% female, 72% White), mean age 16.5 years and body mass index (BMI) 53 kg/m2, 79% met MetS criteria pre-urgery. MetS-z (1.5) and SAD (32cm) were correlated (r = 0.6, P < .0001) presurgery, and both improved significantly at 6 months, 1, and 5 years postsurgery, remaining highly correlated at each timepoint. SAD predicted MetS-z (β = 0.118; 95% CI, 0.109, 0.127) after adjustment for age, visit, surgery type, and caregiver education.

CONCLUSIONS

Abdominal obesity is a key MetS risk marker in youth undergoing weight loss surgery. Both SAD and Met-z measures may be useful for MetS risk assessment and tracking postsurgery changes in this population, but more research is needed to identify effective lifestyle interventions targeting abdominal obesity.

Comparison of Glycosylated Haemoglobin, Blood Pressure, and Anthropometric Measurements Depending on Gender and Bodyweight State in Adolescents

Background/Objective: The greatest anthropometric and physiological changes occur during adolescence. Assessment of growth patterns is necessary to prevent future health risks. Aims: To describe the values of glycosylated haemoglobin (HbA1c), systolic (SBP) and diastolic (DBP) blood pressure, triceps skinfold, and abdominal circumference according to gender and age (between 12 and 17 years), as well as explore the differences between body weight conditions. Methods: A descriptive cross-sectional study was carried out, including 4130 adolescents between 12 and 17 years old. SBP and DBP, HbA1c, triceps skinfold, and abdominal circumference were evaluated. Results: Significant differences were observed between males and females for HbA1c (p < 0.001), SBP (p < 0.001), triceps curl (p < 0.001), and abdominal circumference (p < 0.001), independently of the age group. Regardless of gender and age groups, significant differences were observed between overweight/obese and normal-weight adolescents in SBP (p < 0.001), DBP (p < 0.001 to 0.009), triceps skinfold (p < 0.001), and abdominal perimeter (p < 0.001). Conclusions: Our findings revealed higher SBP, DBP, triceps skinfold, and abdominal circumference in overweight/obese adolescents compared to normal-weight adolescents in both genders.

Visceral adiposity is related to insulin sensitivity and inflammation in adolescents with obesity and mild sleep disordered breathing

OBJECTIVES

To evaluate the relationships between adipose tissue distribution, insulin secretion and sensitivity, sleep-disordered breathing, and inflammation in obese adolescents.

METHODS

Cross-sectional study of 56 obese adolescents who underwent anthropometric measures, dual-energy X-ray absorptiometry, overnight polysomnography, oral glucose tolerance test (OGTT) and frequently sampled intravenous glucose tolerance test. Correlation and regression analyses were used to assess relationships between adiposity, insulin secretion and sensitivity, measures of sleep-disordered breathing (oxyhemoglobin nadir, SpO₂; apnea hypopnea index, AHI; arousal index, AI; maximum end-tidal CO₂; non-REM sleep duration), and inflammation (high-sensitivity C-reactive protein, hsCRP).

RESULTS

Subjects (55% female) were mean (SD) 14.4 (2.1) years, with BMI Z-score of 2.3 (0.4). AHI was >5 in 10 (18%) subjects and 1< AHI ≤5 in 22 (39%). Visceral adipose tissue area (VAT) was positively correlated with OGTT 1 and 2 h insulin and 1 h glucose, and hsCRP (r=0.3-0.5, p≤0.007 for each). VAT was negatively correlated with sensitivity to insulin (r=-0.4, p=0.005) and SpO₂ nadir (r=-0.3, p=0.04) but not with other sleep measures. After adjustment for BMI-Z, sex, population ancestry, age, and sleep measures, VAT remained independently associated with insulin measures and 1 h glucose, but no other measures of glycemia. SAT was not associated with measures of glycemia or insulin resistance.

CONCLUSIONS

Among adolescents with obesity, visceral adiposity was associated with insulin resistance, SpO₂ nadir, and inflammation. The independent association of visceral adiposity with insulin resistance highlights the potential role of VAT in obesity-related chronic disease.

Association of diet quality, physical activity, and abdominal obesity with metabolic syndrome z-score in black and white adolescents in the US

BACKGROUND AND AIMS

Metabolic syndrome (MetS) affects ∼10% of adolescents and is associated with cardiometabolic disease risk. The most prevalent MetS component is abdominal obesity. Healthy diet and physical activity (PA) are inversely associated with abdominal obesity and may reduce MetS risk in youth. Our aim was to examine associations of diet, activity, and abdominal obesity with MetS z-score (MetS-z).

METHODS AND RESULTS

An analysis of National Health and Nutrition Examination Survey (NHANES) 2011-2016 data in adolescents was performed. Healthy Eating Index (HEI)- 2015 scores were calculated for diet quality, PA habits were used to determine alignment with national guidelines, and abdominal obesity was assessed by sagittal abdominal diameter (SAD). MetS-z represented severity or potential risk for MetS. Multivariable regression evaluated the relationships of HEI, SAD and PA with MetS-z. Among 1214 black and white adolescents, SAD was significantly associated with MetS-z [β (95% CI) = 0.17 (0.16, 0.19); P <0.0001] while HEI-2015 components showed associations with MetS-z overall (HEI total, dairy, and sodium scores), and by sex (total, refined grains, dairy for males; added sugar, protein, whole grains for females). Mean HEI-2015 score was 47.4/100 (51.6 using the population-ratio method), and the proportion of adolescents meeting national PA guidelines was 37.6%, yet PA was not a significant predictor of MetS-z.

CONCLUSIONS

US adolescents have poor diet quality and fewer than half meet PA guidelines. Strategies for preventing MetS and related conditions in adolescence should focus on weight management - specifically, abdominal fat reduction - with individualized diet counseling.

What anthropometric indicators are associated with insulin resistance? Cross-sectional study on children and adolescents with diagnosed human immunodeficiency virus

BACKGROUND

Studies that test associations between anthropometric indicators and insulin resistance (IR) need to provide better evidence in the context of the pediatric population (children and adolescents) with human immunodeficiency virus (HIV), as anthropometric indicators present a better explanation of the distribution of body fat.

OBJECTIVE

To test the associations between anthropometric indicators and insulin resistance (IR) among children and adolescents diagnosed with HIV.

DESIGN AND SETTING

Cross-sectional study on 65 children and adolescents (8-15 years) infected with HIV through vertical transmission conducted at the Joana de Gusmão Children's Hospital, Florianópolis, Brazil.

METHODS

The anthropometric indicators measured were the abdominal (ASF), triceps (TSF), subscapular (SSF) and calf (CSF) skinfolds. The relaxed arm (RAC), waist (WC) and neck (NC) circumferences were also measured. Body mass index (BMI) was calculated from the relationship between body mass and height. IR was calculated through the Homeostasis Model Assessment for Insulin Resistance (HOMA-IR). Simple and multiple linear regression analyses were used.

RESULTS

After adjustment for covariates (sex, bone age, CD4+ T lymphocytes, CD8+ T lymphocytes, viral load, and physical activity), associations between IR and models with SSF and CSF remained. Each of these explained 20% of IR variability. For females, in the adjusted analyses, direct associations between IR and models with ASF (R² = 0.26) and TSF (R² = 0.31) were observed.

CONCLUSIONS

SSF and CSF in males and ASF and TSF in females were associated with IR in HIV-infected children and adolescents.

Overweight and Obesity, Body Fat, Waist Circumference, and Anemia in Peruvian University Students: A Cross-Sectional Study

The university represents a critical space for students in terms of prevalence of malnutrition. The objective of this study was to determine the body mass index (BMI), body fat percentage (% BF), waist circumference (WC), and anemia in university students. A cross-sectional study was carried out in 2,285 university students from Lima, Peru. The sample was selected by nonprobability convenience sampling. Anthropometric data and hemoglobin levels were measured. The Chi-square test was used. The analysis of the associated factors was done using binary logistic regression. A significance level of 5% was considered. There were no significant differences between men and women in BMI (p > 0.05). The men presented significantly high and very high levels of % BF (p < 0.001). The proportion of women who presented anemia and high and very high WC was significantly higher compared to men (p < 0.001). Being older than 27 years (OR_B = 2.07; 95% CI = 1.19–3.6), being male (OR_B = 2.68; 95% CI = 2.02–3.55), studying at the engineering faculty (OR_B = 1.39; 95% CI = 1.09–1.79), having excess body fat (OR_B = 8.17; 95% CI = 6.13–10.87), and having an elevated WC (OR_B = 35.51; 95% CI = 25.06–50.33) significantly predicted overweight/obesity. The findings of this study suggest that college students, especially males and those who are not enrolled in health sciences colleges, should be a priority in healthy lifestyle interventions, particularly nutritional education programs, to reduce the prevalence of overweight and obesity.

An Overview of the Role of Adipokines in Cardiometabolic Diseases

Obesity as an independent risk factor for cardiovascular diseases (CVDs) leads to an increase in morbidity, mortality, and a shortening of life span. The changes in heart structure and function as well as metabolic profile are caused by obese people, including those free of metabolic disorders. Obesity alters heart function structure and affects lipid and glucose metabolism, blood pressure, and increase inflammatory cytokines. Adipokines, specific cytokines of adipocytes, are involved in the progression of obesity and the associated co-morbidities. In the current study, we review the scientific evidence on the effects of obesity on CVDs, focusing on the changes in adipokines. Several adipokines have anti-inflammatory and cardioprotective effects comprising omentin, apelin, adiponectin, and secreted frizzled-related protein (Sfrp-5). Other adipokines have pro-inflammatory impacts on the cardiovascular system and obesity including leptin, tumor necrosis factor (TNF), retinol-binding protein4 (RBP-4), visfatin, resistin, and osteopontin. We found that obesity is associated with multiple CVDs, but can only occur in unhealthy metabolic patients. However, more studies should be designed to clarify the association between obesity, adipokine changes, and the occurrence of CVDs.

The range of non-traditional anthropometric parameters to define obesity and obesity-related disease in children: a systematic review

Obesity is defined as an abnormal/excessive accumulation of body fat, associated with health consequences. Although overall obesity does confer a significant threat to the health of individuals, the distribution of body fat, especially abdominal/central obesity is of greater importance. For practical reasons, proxy anthropometric measurements have been developed to identify central obesity, however, major limitations are noted in these traditional measurements. The present study aims to evaluate the literature, to identify and describe non-traditional anthropometric measurements of overweight and obesity in children. The current systematic review was conducted in accordance with the PRISMA guidelines, and the search was undertaken in the PubMed^® database, using MeSH (Medical Subject Headings) terms. Data extracted from each study were: (a) details of the study, (b) anthropometric parameter(s) evaluated in the study and its details, (c) study methods, (d) objectives of the study and/or comparisons, and (e) main findings/conclusions of the study. The search yielded a total of 3697 articles, of which 31 studies were deemed eligible to be included. The literature search identified 13 non-traditional anthropometric parameters. Data on non-traditional anthropometric parameters were derived from 24 countries. Majority were descriptive cross-sectional studies (n = 29), while sample size varied from 65 to 23,043. Non-traditional anthropometric parameters showed variable correlation with obesity and/or related metabolic risk factors. Some parameters involved complex calculations, while others were based on a single anthropometric measurement or derived from traditional measures. Most studies lacked comparison with a 'gold standard' assessment of body fat, hence further research is required to determine their accuracy and precision.

Association Between Abdominal Waist Circumference and Blood Pressure In Brazilian Adolescents With Normal Body Mass Index: Waist circumference and blood pressure in Adolescents

Obesity is the most common chronic disease in adolescents. In adults, waist circumference (WC) is associated with the presence of cardiovascular risk factors and is also a better predictor of cardiovascular (CV) risk than body mass index (BMI). The association between WC and CV risk factors in adolescents has been poorly explored so far, mainly in those within the normal BMI range.

Carotid intima-media thickness, hypertension, and dyslipidemia in obese adolescents

Introduction

Obesity is a global health problem with growing prevalence in developing countries. Obesity causes chronic inflammation due to imbalances between pro- and anti-inflammatory cytokines. This causes metabolic complications such as dyslipidemia, hypertension, and cardiovascular disorder. Carotid intima-media thickness (CIMT) is a predictor of atherosclerosis which could be measured easily and non-invasively. Early detection of cardiovascular diseases in obese adolescents at risk is hoped to improve outcomes.

Methods

This is a cross-sectional study on obese adolescents aged 13-16 year old at Pediatric Clinic of Dr. Soetomo General Hospital. Obesity is defined as Body mass index higher than 95^th percentiles according to CDC (2000). Dyslipidemia is diagnosed when either an increase in cholesterol, LDL, triglyceride or a decrease in HDL level is found, as recommended by NCPE and American Academy of Pediatrics. Hypertension is defined as an increase of blood pressure > P95 according to age and gender. The differences of CIMT based on dyslipidemia, hypertension, and gender were analyzed with Wilcoxon Mann Whitney with significant p value (p < 0,005).

Results

This study included 59 obese adolescents, consisting of 32 (54.2%) male adolescents and 35 (59.3%) female adolescents. Dyslipidemia was found on 38 (64.4%) adolescents and hypertension was found on 35 (59.3%) adolescents. No difference of CIMT was found between obese adolescents with and without dyslipidemia and with and without hypertension based on gender (p > 0.05).

Conclusion

No difference of CIMT based on gender between adolescents aged below 18. The high number of dyslipidemia and hypertension in obese adolescents need an early detection of cardiovascular complication.

Alternative waist-to-height ratios associated with risk biomarkers in youth with diabetes: comparative models in the SEARCH for Diabetes in Youth Study

BACKGROUND/OBJECTIVES

The waist-to-height ratio (WHtR) estimates cardiometabolic risk in youth without need for growth charts by sex and age. Questions remain about whether waist circumference measured per protocol of the National Health and Nutrition Examination Survey (WNHAHtR) or World Health Organization (WWHOHtR) can better predict blood pressures and lipid parameters in youth.

PARTICIPANTS/METHODS

WHtR was measured under both anthropometric protocols among participants in the SEARCH Study, who were recently diagnosed with diabetes (ages 5-19 years; N = 2 773). Biomarkers were documented concurrently with baseline anthropometry and again ~7 years later (ages 10-30 years; N = 1 712). For prediction of continuous biomarker outcomes, baseline WNHAHtR or WWHOHtR entered semiparametric regression models employing restricted cubic splines. To predict binary biomarkers (high-risk group defined as the most adverse quartile) linear WNHAHtR or WWHOHtR terms entered logistic models. Model covariates included demographic characteristics, pertinent medication use, and (for prospective predictions) the follow-up time since baseline. We used measures of model fit, including the adjusted-R2 and the area under the receiver operator curves (AUC) to compare WNHAHtR and WWHOHtR.

RESULTS

For the concurrent biomarkers, the proportion of variation in each outcome explained by full regression models ranged from 23 to 46%; for the prospective biomarkers, the proportions varied from 11 to 30%. Nonlinear relationships were recognized with the lipid outcomes, both at baseline and at follow-up. In full logistic models, the AUCs ranged from 0.75 (diastolic pressure) to 0.85 (systolic pressure) at baseline, and from 0.69 (triglycerides) to 0.78 (systolic pressure) at the prospective follow-up. To predict baseline elevations of the triglycerides/HDL cholesterol ratio, the AUC was 0.816 for WWHOHtR compared with 0.810 for WNHAHtR (p = 0.003), but otherwise comparisons between alternative WHtR protocols were not significantly different.

CONCLUSIONS

Among youth with recently diagnosed diabetes, measurements of WHtR by either waist circumference protocol similarly helped estimate current and prospective cardiometabolic risk biomarkers.

Abdominal obesity, metabolic dysfunction, and metabolic syndrome in U.S. adolescents: National Health and Nutrition Examination Survey 2011-2016

PURPOSE

The objectives were to use National Health and Nutrition Examination Survey data to (1) estimate the prevalence of metabolic syndrome (MetS) risk factors (elevated blood pressure, triglycerides, blood glucose, and low HDL cholesterol); (2) estimate the prevalence of MetS using three common definitions; and (3) compare the odds of MetS risk factors/MetS when using different measures of abdominal obesity (sagittal abdominal diameter [SAD] versus waist circumference [WC]) among U.S. adolescents.

METHODS

Analyses were performed on data collected from adolescents aged 12-19 years (n = 1214) participating in the 2011-2016 National Health and Nutrition Examination Survey. Prevalence of MetS risk factors and MetS were estimated. Unadjusted and adjusted binomial/multinomial logistic regressions were performed to test associations between WC and SAD z-scores and MetS risk factors/MetS. Analyses were performed for all participants and were stratified by sex as well as race/ethnicity.

RESULTS

Males were more likely to have MetS risk factors. Depending on sex and the definition applied, the prevalence of MetS ranged from 2% to 11% and was lowest among females. Adjusted logistic regressions showed that one z-score increase in SAD and WC resulted in similar increased odds of MetS risk factors/MetS, but associations between abdominal obesity and MetS varied by the definition applied and race/ethnicity.

CONCLUSIONS

Metabolic dysfunction and MetS are prevalent among U.S. adolescents, and it is important to consider how MetS components and MetS are measured in population inference.

ANTHROPOMETRY AND CLUSTERED CARDIOMETABOLIC RISK FACTORS IN YOUNG PEOPLE: A SYSTEMATIC REVIEW

OBJECTIVE

To conduct a systematic review of the literature on the ability of anthropometric indicators to predict clustered cardiometabolic risk factors (CMRF) in children and adolescents.

DATA SOURCE

Studies published from June 1st, 2011 to May 31st, 2016 in the PubMed, SciELO and LILACS databases were analyzed. The research was based on keywords derived from the terms "anthropometric indicators" AND "cardiometabolic risk factors". Observational studies on the ability of anthropometric indicators as predictors of clustered CMRF in children and adolescents in Portuguese, English and Spanish languages were included. Studies with a specific group of obese patients or with other diseases were not included.

DATA SYNTHESIS

Of the 2,755 articles retrieved, 31 were selected for systematic review. Twenty-eight studies analyzed body mass index (BMI) as a predictor of clustered CMRF. Only 3 of the 25 cross-sectional studies found no association between anthropometric indicators and clustered CMRF. The results of six studies that compared the predictive ability of different anthropometric measures for clustered CMRF were divergent, and it was not possible to define a single indicator as the best predictor of clustered CMRF. Only six articles were cohort studies, and the findings suggested that changes in adiposity during childhood predict alterations in the clustered CMRF in adolescence.

CONCLUSIONS

BMI, waist circumference and waist-to-height ratio were predictors of clustered CMRF in childhood and adolescence and exhibited a similar predictive ability for these outcomes. These findings suggest anthropometric indicators as an interesting screening tool of clustered CMRF at early ages.

Exercise training at the intensity of maximal fat oxidation in obese boys

The objectives of this study were to explore the effects of 10 weeks of exercise training at the intensity of maximal fat oxidation rate (FATmax) on body composition, cardiovascular fitness, and functional capacity in 8- to 10-year-old obese boys. This is a school-based interventional study. Twenty-six obese boys and 20 lean boys were randomly allocated into the exercise and control groups. Measurements of body composition, FATmax through gas analyses, predicted maximal oxygen uptake, and functional capacity (run, jump, abdominal muscle function, and body flexibility) were conducted at baseline and at the end of experiments. Two exercise groups participated in 10 weeks of supervised exercise training at individualized FATmax intensities, for 1 h per day and 5 days per week. FATmax training decreased body mass (-1.0 kg, p < 0.05), body mass index (-1.2 kg/m(2), p < 0.01), fat mass (-1.2 kg, p < 0.01), and abdominal fat (-0.13 kg, p < 0.01) of the trained obese boys. Their cardiovascular fitness (p < 0.05) and body flexibility (p < 0.05) were also improved after training. The lean boys showed improvements in cardiovascular fitness after training (p < 0.05). FATmax training increased the FATmax in obese boys from 0.35 ± 0.12 g/min to 0.38 ± 0.13 g/min, but this change was not statistically significant. In addition, there was no change in daily energy intake for all participants before and after the experimental period. Results of this study suggest that FATmax is an effective exercise training intensity for the treatment of childhood obesity.

Association between anthropometric indices and cardiometabolic risk factors in pre-school children

BACKGROUND

The world health organization (WHO) and the Identification and prevention of dietary- and lifestyle-induced health effects in children and infants- study (IDEFICS), released anthropometric reference values obtained from normal body weight children. This study examined the relationship between WHO [body mass index (BMI) and triceps- and subscapular-skinfolds], and IDEFICS (waist circumference, waist to height ratio and fat mass index) anthropometric indices with cardiometabolic risk factors in pre-school children ranging from normal body weight to obesity.

METHODS

A cross-sectional study with 232 children (aged 4.1 ± 0.05 years) was performed. Anthropometric measurements were collected and BMI, waist circumference, waist to height ratio, triceps- and subscapular-skinfolds sum and fat mass index were calculated. Fasting glucose, fasting insulin, homeostasis model analysis insulin resistance (HOMA-IR), blood lipids and apolipoprotein (Apo) B-100 (Apo B) and Apo A-I were determined. Pearson's correlation coefficient, multiple regression analysis and the receiver-operating characteristic (ROC) curve analysis were run.

RESULTS

51% (n = 73) of the boys and 52% (n = 47) of the girls were of normal body weight, 49% (n = 69) of the boys and 48% (n = 43) of the girls were overweight or obese. Anthropometric indices correlated (p < 0.001) with insulin: [BMI (r = 0.514), waist circumference (r = 0.524), waist to height ratio (r = 0.304), triceps- and subscapular-skinfolds sum (r = 0.514) and fat mass index (r = 0.500)], and HOMA-IR: [BMI (r = 0.509), waist circumference (r = 0.521), waist to height ratio (r = 0.296), triceps- and subscapular-skinfolds sum (r = 0.483) and fat mass index (r = 0.492)]. Similar results were obtained after adjusting by age and sex. The areas under the curve (AUC) to identify children with insulin resistance were significant (p < 0.001) and similar among anthropometric indices (AUC > 0.68 to AUC < 0.76).

CONCLUSIONS

WHO and IDEFICS anthropometric indices correlated similarly with fasting insulin and HOMA-IR. The diagnostic accuracy of the anthropometric indices as a proxy to identify children with insulin resistance was similar. These data do not support the use of waist circumference, waist to height ratio, triceps- and subscapular- skinfolds sum or fat mass index, instead of the BMI as a proxy to identify pre-school children with insulin resistance, the most frequent alteration found in children ranging from normal body weight to obesity.

Adding anthropometric measures of regional adiposity to BMI improves prediction of cardiometabolic, inflammatory and adipokines profiles in youths: a cross-sectional study

BACKGROUND

Paediatric research analysing the relationship between the easy-to-use anthropometric measures for adiposity and cardiometabolic risk factors remains highly controversial in youth. Several studies suggest that only body mass index (BMI), a measure of relative weight, constitutes an accurate predictor, whereas others highlight the potential role of waist-to-hip ratio (WHR), waist circumference (Waist C), and waist-to-height ratio (WHtR). In this study, we examined the effectiveness of adding anthropometric measures of body fat distribution (Waist C Z Score, WHR Z Score and/or WHtR) to BMI Z Score to predict cardiometabolic risk factors in overweight and obese youth. We also examined the consistency of these associations with the "total fat mass + trunk/legs fat mass" and/or the "total fat mass + trunk fat mass" combinations, as assessed by dual energy X-ray absorptiometry (DXA), the gold standard measurement of body composition.

METHODS

Anthropometric and DXA measurements of total and regional adiposity, as well as a comprehensive assessment of cardiometabolic, inflammatory and adipokines profiles were performed in 203 overweight and obese 7-17 year-old youths from the Paediatrics Clinic, Centre Hospitalier de Luxembourg.

RESULTS

Adding only one anthropometric surrogate of regional fat to BMI Z Score improved the prediction of insulin resistance (WHR Z Score, R(2): 45.9%. Waist C Z Score, R(2): 45.5%), HDL-cholesterol (WHR Z Score, R(2): 9.6%. Waist C Z Score, R(2): 10.8%. WHtR, R(2): 6.5%), triglycerides (WHR Z Score, R(2): 11.7%. Waist C Z Score, R(2): 12.2%), adiponectin (WHR Z Score, R(2): 14.3%. Waist C Z Score, R(2): 17.7%), CRP (WHR Z Score, R(2): 18.2%. WHtR, R(2): 23.3%), systolic (WHtR, R(2): 22.4%), diastolic blood pressure (WHtR, R(2): 20%) and fibrinogen (WHtR, R(2): 21.8%). Moreover, WHR Z Score, Waist C Z Score and/or WHtR showed an independent significant contribution according to these models. These results were in line with the DXA findings.

CONCLUSIONS

Adding anthropometric measures of regional adiposity to BMI Z Score improves the prediction of cardiometabolic, inflammatory and adipokines profiles in youth.

Body mass index (BMI) trajectories in infancy differ by population ancestry and may presage disparities in early childhood obesity

CONTEXT

No consensus definition exists for excess adiposity during infancy. After age 2 years, high body mass index (BMI) is related to adverse cardiometabolic outcomes. Before age 2 years, the utility of BMI as a metric of excess adiposity is unknown.

OBJECTIVES

The objective of the study was to characterize infant BMI trajectories in a diverse, longitudinal cohort and investigate the relationship between the infancy BMI trajectory and childhood obesity.

SUBJECTS

Healthy, nonpreterm infants (n = 2114) in the Genetic Causes for Complex Pediatric Disorders study (The Children's Hospital of Philadelphia) with six or more BMI measurements in the first 13.5 months participated in the study.

DESIGN

For each infant, the BMI trajectory was modeled using polynomial regression. Independent effects of clinical factors on magnitude and timing of peak BMI were assessed. The relationship between infancy BMI and early childhood BMI (age 4 y) was examined (n = 1075).

RESULTS

The cohort was 53% male and 61% African-American. Peak BMI was 18.6 ± 1.7 kg/m(2) and occurred at 8.6 ± 1.4 months. In multivariate analysis, boys had a higher (0.50 kg/m(2), P < .001) peak BMI than girls. The peak was higher (0.53 kg/m(2), P ≤ .001) and occurred earlier (by 12 d, P < .001) in African-American vs white children. The odds of obesity at age 4 years increased among children with higher (odds ratio 2.02; P < .001) and later (odds ratio 1.26; P = .02) infancy peak BMI.

CONCLUSIONS

We demonstrate sex- and ancestry-specific differences in infancy BMI and an association of infancy peak BMI with childhood BMI. These findings support the potential utility of infancy BMI to identify children younger than age 2 years with increased risk for later obesity.

Distinct gender differences in anthropometric profiles of a peri-urban South African HIV population: a cross sectional study

Background

Highly active antiretroviral therapy (HAART) has extended life expectancy and enhanced the well-being of HIV-positive individuals. Since there are concerns regarding HAART-mediated onset of cardio-metabolic diseases in the long-term, we evaluated the anthropometric profile of black HIV-infected individuals in a peri-urban setting (Western Cape, South Africa).

Methods

A cross sectional study design was followed to describe the gender differences in different HAART treatment groups. HIV-positive patients (n = 44 males, n = 102 females; 20–40 years) were recruited for three groups: 1) control (HIV-positive, HAART-naïve), 2) HIV-positive (<3 years HAART), and 3) HIV-positive (>3 years HAART).

Results

All participants underwent comprehensive anthropometric and bio-electrical impedance analyses. No significant differences were observed in the male treatment groups. HAART-naïve females are mostly overweight (73.90 ± 2.79). This is followed by a period of muscle wasting seen in the triceps skinfold (29.30 ± 2.19 vs 20.63 ± 1.83; p < 0.01), muscle mass (22.23 ± 0.46 vs 19.82 ± 0.54; p < 0.01), and fat free mass (49.40 ± 1.08 vs 44.16 ± 1.21; p < 0.01) upon HAART initiation (<3 years HAART). Thereafter all parameters measured had levels similar to that seen for the female HAART-naïve group. Females on <3 years HAART exhibited significantly decreased body cell mass (p < 0.01), protein mass (p < 0.01), muscle mass (p < 0.01), fat free mass (p < 0.01), and fat mass (p < 0.001) versus matched HAART-naïve controls. The W:H ratio for the female treatment groups placed the females overall at a higher risk for developing cardiovascular disease compared to the males.

Conclusions

This study found striking gender-based anthropometric differences in black South African HIV-positive individuals on HAART. We also conclude from this observational study that no significant differences were found in the different male treatment groups. All female body composition parameters initially showed lower values (<3 years HAART). The female treatment group (>3 years HAART) displayed values similar to that seen in the HAART-naïve group. Higher W:H ratios in females receiving longer-term HAART potentially increases their risk for the future onset of cardio-metabolic complications.

Medical and non-medical complications among children and adolescents with excessive body weight

BACKGROUND

The burden of disease from childhood obesity is considerable worldwide, as it is associated with several co-morbidities, such as dyslipidemia, hypertension, type 2 diabetes (T2DM), orthopedic and psychosocial problems. We aimed at determining the prevalence of these complications in a population of children and adolescents with body weight excess.

METHODS

This is a cohort study including 774 new patients (1.7 - 17.9 yrs, mean 11.1 ± 3.0) attending a pediatric obesity care center. We assessed personal and family medical histories, physical examination, systemic blood pressure, biochemical screening tests.

RESULTS

We found that the great majority of the children suffered from at least one medical complication. Orthopedic pathologies were the most frequent (54%), followed by metabolic (42%) and cardiovascular disturbances (31%). However, non-medical conditions related to well-being, such as bullying, psychological complaints, shortness of breath or abnormal sleeping patterns, were present in the vast majority of the children (79.4%). Family history of dyslipidemia tends to correlate with the child's lipids disturbance (p = .053), and ischemic events or T2DM were correlated with cardiovascular risk factors present in the child (p = .046; p = .038, respectively).

CONCLUSIONS

The vast majority of obese children suffer from medical and non-medical co-morbidities which must be actively screened. A positive family history for cardiovascular diseases or T2DM should be warning signs to perform further complementary tests. Furthermore, well-being related-complaints should not be underestimated as they were extremely frequent.