Association of anthropometric indices with cardiovascular disease risk factors among children and adolescents: CASPIAN Study

Association between Urinary Sodium Excretion and Body Fat in School-Aged Children: Insights from the ARIA Study

Childhood obesity has been associated with increased sodium intake. Nonetheless, evidence linking sodium intake to Body Mass Index (BMI) and Body Fat Mass Percentage (%BF) remains limited, especially in the pediatric age group. Therefore, this study aims to investigate whether there is an association between 24 h urinary sodium excretion with BMI and %BF in a sample group of children from the ARIA study. This cross-sectional analysis included 303 children aged 7 to 12 from across 20 public schools in Porto, Portugal. Weight and %BF were assessed using the Tanita™ BC-418 Segmental Body Analyzer. Children's Total Energy Intake (TEI) was estimated through a single 24 h Recall Questionnaire, and urinary sodium and potassium excretion was estimated by a 24 h urine collection. The association of %BF and BMI with 24 h sodium excretion was estimated by a binary logistic regression adjusted for sex, age, physical activity, total energy intake, parental education, and 24 h urinary excreted potassium. There was a significant positive association between higher levels of urinary sodium excretion and higher %BF values, even after adjusting for confounders. However, the same was not observed for BMI. Our findings suggest that higher sodium intake is associated with higher values of %BF among children, regardless of TEI and potassium intake.

Lipid Profile and the Frequency of Dyslipidemia in Iranian Adolescents with Severe Obesity, Who Were Candidates for Bariatric Surgery

PURPOSE

Although several studies have investigated the prevalence of dyslipidemia in adults undergoing bariatric surgery, the experience is limited in adolescents. This study aimed to evaluate the serum lipid profile and prevalence of dyslipidemia in Iranian adolescents with severe obesity undergoing bariatric surgery.

MATERIALS AND METHODS

In this cross-sectional study, a total of 92 adolescents, aged < 20 years, with severe obesity (body mass index (BMI) ≥ 99th percentile), who were candidates for bariatric surgery were enrolled during 2016-2018. The fasting serum levels of total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C) were measured in this study. Dyslipidemia was defined as TC, LDL-C, and TG ≥ 95th percentile or HDL-C < 10th percentile for age and sex.

RESULTS

The mean age of the participants was 17.32 ± 1.88 years (age range, 11-19 years). Overall, 60.9% of the participants were female. Based on the results, 68.48% of the adolescents had dyslipidemia. The most frequent lipid disorder was hypertriglyceridemia (48.9%), followed by low HDL-C (39.6%), hypercholesterolemia (18.5%), and high LDL-C (16.5%). The serum concentrations of lipid components were not significantly different according to sex and age.

CONCLUSION

The prevalence of dyslipidemia was found to be high among Iranian adolescents with severe obesity. Hypertriglyceridemia and low HDL-C were the most common types of dyslipidemia in this population. Therefore, screening for dyslipidemia may be clinically useful in adolescents with severe obesity; timely diagnosis and treatment may prevent the occurrence of coronary events in the future.

Full-Day Physical Activity and Sedentary Behaviour Levels of Typically Developing Children and Adolescents in the Middle East: A Systematic Review

Physical activity (PA) and sedentary behaviour (SB) are important components of physical behaviour associated with long-term health outcomes. Environmental and cultural factors may influence physical behaviour. To explore full day PA and SB in children and adolescents (2-18 years old) in the Middle East, a systematic literature review was performed including 183 journal articles. A wide range of PA and SB outcomes were reported, in some cases making synthesis of results difficult. As a consequence, results were generally reported narratively (MVPA time, total PA, SB time). Meta-regression of daily step count revealed females took 4600 fewer steps than males, with 3000 fewer steps on weekdays than weekends, and overweight individuals taking 2800 fewer steps/day. Steps decreased with age. Meta-regression for TV viewing time demonstrated an increase by 0.04 h per year of age. Even though environmental and cultural conditions may be different, PA and SB of children and adolescents in the Middle East were largely comparable to those of Europeans and North Americans. The wide range of data collection instruments used (both self-report questionnaire and body-worn devices) and heterogeneity of data made synthesis of reported data across studies very difficult, suggesting a need for greater standardisation of data collection methods.

Changes in body composition and cardiometabolic risk factors in relation to the reduction in body mass index in adolescents with obesity

INTRODUCTION

there are controversial data in relation to the reduction in body mass index standard deviation score (BMI-SDS) needed to improve adiposity in the pediatric population with obesity. The aim of this work was to determine the minimum variation in BMI-SDS required to improve the values of adiposity markers and cardiometabolic risk factors in growing adolescents with obesity.

METHODS

a longitudinal study consisting of clinical evaluation (waist circumference, waist-to-height ratio, fat mass index, and blood pressure) and blood testing (insulin resistance and lipid profile) was conducted in 350 adolescents with obesity (152 boys and 198 girls) aged 10.2-14.3 years who went through a combined intervention (12 months).

RESULTS

a decrease in SDS-BMI ≤ 0.5 was not associated with any significant improvement in the clinical features and blood testing recorded. A decrease in BMI-SDS > 0.5, and especially if > 1.0, was linked to a significant improvement in adiposity markers. A decrease in BMI-SDS > 0.5 was associated with a significant improvement in insulin resistance, and a decrease in BMI-SDS > 1.0 was associated with a significant decrease in the percentage of patients who showed high values of systolic blood pressure, HOMA-IR, and lipid profile Conclusions: improvement in body composition, insulin resistance, and lipid profile can be observed with reductions in BMI-SDS ≥ 0.5 in obese adolescents, while extended benefits are obtained by losing at least 1.0 BMI-SDS.

Distribution of waist-to-height ratio and cardiometabolic risk in children and adolescents: a population-based study

This study was performed to evaluate the waist-to-height ratio (WHtR) distribution and assess its relationship with cardiometabolic risk in children and adolescents. A total of 8091 subjects aged 10–18 years were included from a nationally representative survey. Participants were classified into three groups: (1) < 85th, (2) ≥ 85th and < 95th, and (3) ≥ 95th percentile of WHtR. The WHtR distribution varied with sex and age. Whereas WHtR decreased from age 10–15 years in boys and from age 10–12 years in girls, it slightly increased thereafter. Compared to the < 85th percentile group, the WHtR ≥ 85th and < 95th percentile group had an odds ratio (OR) of 1.2 for elevated blood pressure (BP), 1.89 for elevated triglycerides (TGs), 1.47 for reduced high-density lipoprotein cholesterol (HDL-C) and 4.82 for metabolic syndrome (MetS). The ≥ 95th percentile group had an OR of 1.4 for elevated BP, 2.54 for elevated glucose, 2.22 for elevated TGs, 1.74 for reduced HDL-C, and 9.45 for MetS compared to the < 85th percentile group. Our results suggest that sex- and age-specific WHtR percentiles can be used as a simple clinical measurement to estimate cardiometabolic risk.

Consumption of melatonin supplement improves cardiovascular disease risk factors and anthropometric indices in type 2 diabetes mellitus patients: a double-blind, randomized, placebo-controlled trial

BACKGROUND

Diabetes mellitus is a common chronic disease. Dyslipidemia and hypertension are two complications that may develop in diabetic patients if hyperglycemia, insulin resistance, and weight gain are not controlled. This study investigated the effects of melatonin supplementation on some cardiovascular disease risk factors and anthropometric indices in patients with type 2 diabetes mellitus (T2DM).

MATERIALS AND METHODS

In this double-blind, randomized, placebo-controlled trial, 50 T2DM patients were randomly allocated to intervention and control groups which received two tablets of either melatonin or placebo (250 mg) once a day for 8 weeks. Systolic blood pressure (SBP), mean arterial pressure (MAP), pulse pressure (PP), the atherogenic index of plasma (AIP), weight, body mass index (BMI), waist and hip circumference (WC, HC), a body shape index (ABSI), abdominal volume index (AVI), body adiposity index (BAI), lipid accumulation product (LAP), conicity index, and waist-to-height ratio (WHtR) were evaluated in all the patients pre- and post-intervention.

RESULTS

Melatonin supplementation for 8 weeks significantly decreased the mean levels of SBP, MAP, PP, weight, BMI, WC, HC, BAI, AVI, conicity index, and WHtR post-intervention (p <  0.05). Also, the median changes of SBP, MAP, PP, weight, BMI, WC, HC BAI, AVI, and conicity index were significantly lower in the intervention group compared with the control group (p <  0.05). A significant increase (p <  0.001) was observed in the mean levels of ABSI in the intervention group. The median changes of ABSI were significantly greater in the intervention group compared with the control group (p <  0.001).

CONCLUSIONS

Consumption of melatonin supplement may be effective in controlling arterial pressure including SBP, MAP, and PP and anthropometric indices (as predictors of obesity) in T2DM patients.

TRIAL REGISTRATION

Iranian Registry of Clinical Trials IRCT20190303042905N1 . Registered on 17 May 2019.

Growth and socio-economic status, influence on the age at menarche in school going girls

INTRODUCTION

Onset age at menarche has been considered an important indicator of reproductive maturity in females and reflects the health status of the population. The purpose of this study was to determine the mean menarcheal age and to examine whether anthropometric and socio-economic status (SES) influences age at menarche in the girls from Punjab province of Pakistan.

METHODS

In this population-based cross-sectional study, 10,050 school-going girls aged 8-16 years from 35 schools across 12 districts of Punjab were recruited. Menarcheal data was obtained by using a questionnaire, while the anthropometric data were obtained by the measurements of standing height, body weight, waist, and hip circumference. The anthropometric indices of pre- and post-menarcheal girls were compared. Student's t-test, ANOVA, and post-hoc Tukey's test was applied for comparison between two and multiple groups respectively, P < 0.05 was considered statistically significant.

RESULTS

There was a normal distribution of age at menarche and mean was 12.4 years in the study population. The girls who reached menarche were found to be taller and heavier with higher BMIs, having a greater waist and hip circumference as compared to their pre-menarcheal peers. Waist-hip-ratio was less, and the waist-to-height ratio was higher in post-menarcheal as compared to pre-menarcheal girls. The girls belonging to low SES had delayed onset of menarche as compared to those belonging to middle/high SES.

CONCLUSION

The age at menarche was associated with SES and changes in various anthropometric measurements reflecting the growth status of girls.

Association of anthropometric indices with cardiovascular disease risk factors among adults: a study in Iran

AIMS

Cardiovascular diseases (CVDs) are the leading cause of death in the world. Many modifiable risk factors have been reported to synergistically act in the development of CVDs. We aimed to compare the predictive power of anthropometric indices, as well as to provide the best cut-off point for these indicators in a large population of Iranian people for the prediction of CVDs and CVD risk factors.

METHODS AND RESULTS

All the data used in the present study were obtained from Khuzestan comprehensive health study (KCHS). Anthropometric indices, including BMI (body mass index), WC (waist circumference), HC (hip circumference), WHR (waist-to-hip ratio), WHtR (waist-to-height ratio), ABSI (a body shape index), as well as CVD risk factors [dyslipidaemia, abnormal blood pressure (BP), and hyperglycaemia] were recorded among 30 429 participants. WHtR had the highest adjusted odds ratios amongst anthropometric indices for all the risk factors and CVDs. WC had the highest predictive power for dyslipidaemia and hyperglycaemia [area under the curve (AUC) = 0.622, 0.563; specificity 61%, 59%; sensitivity 69%, 60%; cut-off point 87.95, 92.95 cm, respectively], while WHtR had the highest discriminatory power for abnormal BP (AUC = 0.585; specificity 60%; sensitivity 65%; cut-off point 0.575) and WHR tended to be the best predictor of CVDs (AUC = 0.527; specificity 58%; sensitivity 64%; cut-off point 0.915).

CONCLUSION

In this study, we depicted a picture of the Iranian population in terms of anthropometric measurement and its association with CVD risk factors and CVDs. Different anthropometric indices showed different predictive power for CVD risk factors in the Iranian population.

Can environmental pollutant bisphenol A increase metabolic risk in polycystic ovary syndrome?

BACKGROUND

Bisphenol A (BPA), a widespread industrial substance is recognized as endocrine disrupting chemical and therefore could be associated with polycystic ovary syndrome (PCOS) related metabolic disturbances.

PATIENTS

In this study 29 women of reproductive age with diagnosed PCOS were enrolled.

METHODS

BPA in urine samples was analyzed by gas chromatography-mass spectrometry.

RESULTS

BPA was detected in urines of 48.28% participants. The waist-to-height ratio (WtHR) was statistically significant higher in PCOS BPA+ in comparison to PCOS BPA- women (p = 0.046). PCOS BPA+ women had 6.88 times (95%Cl 1.3481-35.0600, z = 2.319, p = 0.020) higher risk for waist circumference above 80 cm and 4.95 odds (95%Cl 1.0169-24.096, z = 1.981, p = 0.048) to have WtHR over 0.5 when compared to PCOS BPA-. Statistically significant positive association between BPA urine concentrations and insulin serum levels (p = 0.038) was obtained. BPA urine values were associated with elevated HOMA-IR values and reduced HDL levels with moderate significance (p = 0.079 and p = 0.061, respectively). Also, there was 3.75 times (95%Cl 0.7936-17.7203, z = 1.668, p = 0.095) higher risk for PCOS BPA+ women to have testosterone levels above reference values.

CONCLUSION

The obtained results suggested that the BPA exposition in PCOS women was followed by increased metabolic risk through promotion of obesity, especially the visceral type, hyperinsulinemia, insulin resistance, dyslipidemia and elevated androgen levels.

The predictive value of anthropometric indices for cardiometabolic risk factors in Chinese children and adolescents: A national multicenter school-based study

Objectives

This study aimed to assess the accuracy of body mass index (BMI) percentile, waist circumference (WC) percentile, waist-height ratio, and waist-hip ratio for identifying cardiometabolic risk factors in Chinese children and adolescents stratified by sex and BMI categories.

Methods

We measured anthropometric indices, fasting plasma glucose, lipid profile and blood pressure for 15698 participants aged 6–17 in a national survey between September and December 2013. The predictive accuracy of anthropometric indices for cardiometabolic risk factors was examined using receiver operating characteristic (ROC) analyses. The DeLong test and Z test were used for the comparisons of areas under ROC curves (AUCs).

Results

The prevalence of impaired fasting glucose, dyslipidemia, hypertension and cluster of risk factors were 2.9%, 27.3%, 10.5% and 5.7% respectively. The four anthropometric indices showed poor to fair discriminatory ability for cardiometabolic risk factors with the AUCs ranging from 0.53–0.72. Each index performed significantly better AUCs for dyslipidemia (0.59–0.63 vs. 0.56–0.59), hypertension (0.62–0.70 vs. 0.55–0.65) and clustered risk factors (0.70–0.73 vs. 0.60–0.64) in boys than that in girls. BMI percentile performed the best accuracy for hypertension in both sexes; WC percentile had the highest AUC for dyslipidemia and BMI percentile and waist-height ratio performed similarly the best AUCs for clustered risk factors in boys while BMI percentile, WC percentile and waist-height ratio performed similar and better AUCs for dyslipidemia and clustered risk factors in girls; whereas waist-hip ratio was consistently the poorest predictor for them regardless of sex. Though the anthropometric indices were more predictive of dyslipidemia, hypertension and clustered risk factors in overweight/obese group compared to their normal BMI peers, the AUCs in overweight/obese group remained in the poor range below 0.70.

Conclusions

Anthropometric indices are not effective screening tools for pediatric cardiometabolic risk factors, even in overweight/obese children.

Physical Fitness and Anthropometric Values Among Lithuanian Primary School Children: Population-Based Cross-Sectional Study

Emeljanovas, A, Mieziene, B, Cesnaitiene, VJ, Fjortoft, I, and Kjønniksen, L. Physical fitness and anthropometric values among Lithuanian primary school children: population-based cross-sectional study. J Strength Cond Res 34(2): 414-421, 2020-The purpose of the current study was to derive representative reference scores on anthropometric measures and test scores for the musculoskeletal, motor, and cardiorespiratory fitness of Lithuanian primary school children according to age and sex. This cross-sectional design study included 3,456 Lithuanian first- to fourth-grade children from age 6 to 10 years. Physical fitness was measured using a nine-item test battery developed by Fjørtoft et al. The test battery included the following tests: standing broad jump (explosive strength), jumping a distance of 7 m on 2 feet, jumping a distance of 7 m on 1 foot (both tests indicate leg muscle strength), throwing a tennis ball with one hand, and pushing a medicine ball with 2 hands (both tests indicate arm muscle strength). These tests measured musculoskeletal fitness. In addition, there were measures of a 10 × 5-m shuttle run (agility), running 20 m as fast as possible (speed), and climbing wall bars (coordination)-general tests of motor fitness. Reduced 6-minute Cooper test (endurance) measured cardiorespiratory fitness. A Student's t test and analysis of variance were performed to indicate differences between sexes and across age, respectively. The significant differences in mean scores in anthropometric and fitness means indicated that boys had higher scores than girls, and older children scored higher than younger children (p < 0.05). Data on normative sex- and age-specific percentile values (3rd, 10th, 25th, 50th, 75th, 90th, and 97th) for physical fitness tests in Lithuanian primary school children are provided. These data are useful for educational settings, parents, clinicians, sports organizations, and sports clubs in identifying problems or outstanding performance and providing sports programs that develop children's athletic performance.

Predictive Values of Anthropometric Measurements for Cardiometabolic Risk Factors and Cardiovascular Diseases Among 44 048 Chinese

Background The predictive value of adiposity indices and the newly developed index for cardiometabolic risk factors and cardiovascular diseases (CVDs) remains unclear in the Chinese population. This study aimed to compare the predictive value of A Body Shape Index with other 5 conventional obesity-related anthropometric indices (body mass index, waist circumference, hip circumference, waist-to-hip ratio, waist-to-height ratio) in Chinese population. Methods and Results A total of 44 048 participants in the study were derived from the baseline data of the PURE-China (Prospective Urban and Rural Epidemiology) study in China. All participants' anthropometric parameters, CVDs, and risk factors (dyslipidemia, abnormal blood pressure, and hyperglycemia) were collected by standard procedures. Multivariable logistic regression models and receiver operator characteristic curve analysis were used to evaluate the predictive values of obesity-related anthropometric indices to the cardiometabolic risk factors and CVDs. A positive association was observed between each anthropometric index and cardiometabolic risk factors and CVDs in all models (P<0.001). Compared with other anthropometric indices (body mass index, waist circumference, hip circumference, waist-to-hip ratio, and A Body Shape Index), waist-to-height ratio had significantly higher areas under the curve (AUCs) for predicting dyslipidemia (AUCs: 0.646, sensitivity: 65%, specificity: 44%), hyperglycemia (AUCs: 0.595, sensitivity: 60%, specificity: 45%), and CVDs (AUCs: 0.619, sensitivity: 59%, specificity: 41%). Waist circumference showed the best prediction for abnormal blood pressure (AUCs: 0.671, sensitivity: 66%, specificity: 40%) compared with other anthropometric indices. However, the new body shape index did not show a better prediction to either cardiometabolic risk factors or CVDs than that of any other traditional obesity-related indices. Conclusions Waist-to-height ratio appeared to be the best indicator for dyslipidemia, hyperglycemia, and CVDs, while waist circumference had a better prediction for abnormal blood pressure.

Effectiveness of a multi-faceted intervention among elementary school children

Childhood obesity has been shown to be closely related to future obesity and comorbidities. As its prevalence and impact has increased significantly worldwide, researchers have focused on prevention and intervention. This study assessed a multifaceted intervention for elementary school children.A retrospective data collection with a cohort analysis was employed. A 16-week school-based intervention with nutritional intervention, physical activity, and behavioral education was designed and conducted by a multidisciplinary team for 1860 children aged 6 to 13 years. Basic information, anthropometrics, and physical fitness (PF) were recorded before and after the intervention. The differences compared with a reference group, and compared between subgroups, were analyzed.Significant favorable changes in body weight and composition were found. Children's height, weight, and muscle weight increased, whereas BMI, BMI z-score (zBMI), waist circumference, hip circumference, waist-hip ratio, waist-height ratio, body fat percentage, and visceral fat area decreased. Sit-ups and 800-m run time significantly improved. Girls exhibited a greater reduction in body weight outcomes; boys improved more in body composition and PF. Students with higher zBMI had a greater reduction in all anthropometrics; students with lower zBMI showed greater PF improvement, except for the 800-m run.The intervention improved weight measures, body composition, and PF. Subgroup differences suggested the need for sex- and weight-specific interventions.

Using Anthropometric Indicator to Identify Hypertension in Adolescents: A Study in Sarawak, Malaysia

This cross-sectional study was conducted to determine the predictive power of anthropometric indicators and recommend cutoff points to discriminate hypertension among adolescents in Sarawak, Malaysia. A total of 2461 respondents aged 12-17 years participated in this study with mean age of 14.5±1.50 years. All anthropometric indicators had significant area under the ROC curve, with body mass index (BMI) and waist circumference (WC) ranging from 0.7 to 0.8. The best anthropometric indicators for predicting hypertension for boys were WC, BMI, and waist-to-height ratio (WHtR). For girls, BMI was the best indicators followed by WHtR and WC. The recommended BMI cutoff point for boys was 20 kg/m² and 20.7 kg/m² for girls. For WC, the recommended cutoff point was 67.1 cm for boys and 68.2 cm for girls. BMI and WC indicators were recommended to be used at the school setting where the measurement can easily be conducted.

Prevalence of cardiometabolic risk factors in a nationally representative sample of Iranian children and adolescents: the CASPIAN-V Study

Introduction: This study presents the prevalence of cardiometabolic risk factors in a nationally representative sample of Iranian children and adolescents. Methods: This multi-centric study was conducted in 2015 among 4200 students aged 7-18 years. They were selected by multistage cluster sampling from 30 provinces of Iran. Anthropometric indices, biochemical and clinical parameters were measured. Results: The mean of weight, height, waist circumference (WC), systolic blood pressure (SBP), diastolic blood pressure (DBP), and fasting blood glucose (FBG) was higher in boys than in girls (P < 0.05). The mean of triglyceride (TG), total cholesterol (TC) and low-density lipoprotein (LDL) levels were higher in girls than in boys (P < 0.05). The mean of weight, height, WC, SBP, DBP, alanine transaminase (ALT) and body mass index (BMI) was higher in urban than in rural residents (P < 0.05). Overall, 16.1%, 9.4% and 11.4% were underweight, overweight and obese. Abdominal obesity was documented in 21.6% of boys and 20.5% of girls. Low HDL-C was the most prevalent abnormality of lipid profile (29.5%) followed by high serum TGs (27.7%). Low HDL-C was more prevalent in boys than in girls (32.7% vs. 26%, respectively, P < 0.05). Prevalence of obesity and overweight were higher in girls than in boys (P < 0.05). The prevalence of obesity and overweight, abdominal obesity, and low HDL-C were higher in urban than in rural residents (P < 0.05). Conclusion: We found considerably high prevalence of some cardiometabolic risk factors including overweight and obesity, low HDL-C and hypertriglyceridemia in Iranian children and adolescents. The current findings underscore the necessity of intensifying health interventions for primordial and primary prevention of non-communicable diseases from early life.

Blood pressure is associated with body adiposity indicators in children aged 4 to 7 years

INTRODUCTION AND OBJECTIVE

Studies in adults have shown an association between increased adiposity and hypertension, but few studies have analyzed this association in childhood. The aim of this study was to investigate the association between blood pressure (BP) and body adiposity indicators in children, controlling for the variables of birth conditions, sociodemographics, lifestyle and diet.

METHODS

In this cross-sectional study of 399 children aged 4 to 7 years, the dependent variable was BP, measured according to the protocol established by the 7th Brazilian Guidelines on Hypertension. The explanatory variables of the study were waist-to-height ratio (WHtR) and body mass index (BMI). Multiple linear regression was used to assess the independent association between adiposity and BP indicators adjusted for the variables of birth conditions, sociodemographics, lifestyle and diet. Statistical significance was set as α=5%.

RESULTS

BMI for age and WHtR correlated positively with systolic (SBP) and diastolic blood pressure (DBP). After multivariate analysis, higher values of BMI (model 1) and WHtR (model 2) were associated with increased SBP and DBP.

CONCLUSION

Increased body adiposity, as assessed by BMI and WHtR, was associated with increased SBP and DBP among the children studied. Thus, we suggest the use of BMI and WHtR in the nutritional assessment of children to detect changes in BP and other cardiometabolic risk factors in this population.

Eating breakfast and snacks while television viewing are associated with some cardio metabolic risk factors among Iranian children

AIM

We aimed to investigate the association of eating meals while television viewing (TVV) and screen-based behaviors with cardio metabolic risk factors (CRFs) among school-aged children in Shiraz.

MATERIALS AND METHODS

This cross-sectional study was done on 409 primary school children (217 boys), aged 6-9 years. Physical activity, time spent on screen-based behaviors and frequency of eating meals while TVV were measured using a questionnaire. Anthropometric indices, fasting blood sugar (FBS), blood lipids, blood pressure (BP), dietary intakes and physical activity were assessed. Association of eating while TVV with CRFs were assessed using linear regression, adjusted for potential confounders. All statistical analysis were conducted using the Stata 13 software.

RESULTS

Fully adjusted model showed that TVV time had significant positive association with waist circumferences (WC), and BP (p <0.05). Also, we found an inverse relationship between using Computer and Video games with TG level (β=-0.3; CI: -0.64, -0.09). Children who ate two or more breakfast meal while TVV had higher WC (β=2.02; CI: 0.51, 3.53) and FBS (β=3.58; CI: 0.39, 6.78) compared to who never ate breakfast while TVV. After adjustment for Screen time and BMI, eating snacks while TVV was positively associated with FBS and systolic BP. However, Eating dinner and lunch while TVV were not significantly associated with any of CRFs after adjustment for confounders.

CONCLUSIONS

We found that both eating breakfast and snacks while TVV were associated with WC, FBS and BP in children. Also, excessive TVV was associated with WC and BP.

Waist-to-height ratio and sedentary lifestyle as predictors of metabolic syndrome in children in Ecuador

OBJECTIVE

To determine the predictors and prevalence of metabolic syndrome (MS) and the presence of vascular inflammation in apparently-normal children (10-15 years) of both sexes in Guayaquil, Ecuador.

STUDY DESIGN AND METHODS

We included 395 apparently-healthy students from a middle-income school in a cross-sectional survey. Informed consent was obtained from students and parents. Anthropometric measurements including blood pressure (BP), body mass index (BMI) and waist-to-height ratio (WHtR), and blood tests were recorded. Vascular inflammation parameters were assessed. Percentiles of the different parameters were used, and MS was defined according to National Cholesterol Education Program Adult Treatment Panel III criteria (NCEP-ATPIII). Waist circumference>P 75, blood pressure>P 90, glucose>100mg/dl, triglycerides>100mg/dl, HDL<45mg/dl. If 3 of the 5 criteria were present, this was considered MS.

RESULTS

The mean age was 12 years (186 boys, 209 girls). The overall prevalence of MS was 9.37% (6.33% in girls, 3.04% in boys). Sustained hypertension was detected in 6.6% of children and pre-hypertension in 7.1%. Obesity was found in 1.8% of subjects, and overweight in 15.2%. Triglycerides has a RR 2.34 (1.97-2.76); HOMA index has a RR 1.97(1.62-2.40); HDL cholesterol has a RR 1.84(1.58-2.13); Insulin level has a RR 1.53(1.40-1.67) and interleukin 6 has RR 1.83(1.20-2.79). Serum glucose, total cholesterol and LDL-Cholesterol had no association with the metabolic syndrome. HDL-Cholesterol<45mg/dl and triglyceride>100mg/dl were present in 70% of subjects with MS. The WHtR threshold≥0.5 was 100% sensitive in both sexes (67% specificity in boys and 69% in girls). There were significant associations between the WHtR and pre-hypertension and sedentary lifestyle (P<0.001 and P<0.003 respectively). A WHtR value of ≥0.50 indicated a 2.2-fold increased risk of MS compared with normal WHtR, and normal weight.

CONCLUSIONS

A WHtR≥0.5 was 100% sensitive in detecting MS in 10-15 year-old boys and girls in the normal or overweight range of the BMI. This assessment is a simple and practical tool for use in population-based studies of cardiovascular risk. When combined with pre-hypertension and a sedentary lifestyle, the WHtR is highly sensitive in predicting MS.

Logic Regression Analysis of Gene Polymorphisms and HDL Levels in a Nationally Representative Sample of Iranian Adolescents: The CASPIAN-III Study

BACKGROUND

To investigate the associations of genetic polymorphism with high-density lipoprotein-cholesterol (HDL-C) levels in Iranian adolescents.

METHODS

This multicentre study was conducted on 10 - 18 year-old students from 27 provinces in Iran. Logic regression approach was used to determine the main effects and interactions of polymorphisms related to HDL-C levels.

RESULTS

The rs708272 polymorphism was significantly related to HDL-C levels. Moreover, rs708272 increased HDL-C levels and had a protective effect on HDL-C. The interaction of rs2230808 and rs5880 polymorphisms as well as the interaction of rs320 and rs708272 polymorphisms were associated with lower HDL-C levels. Furthermore, the interaction of rs320 and rs1801177 polymorphisms was associated with lower HDL-C levels.

CONCLUSIONS

We found that not only single SNPs, but also interactions of several SNPs affect HDL-C levels. Given the high prevalence of low HDL-C in Middle Eastern populations, further genetic studies are required for detailed analysis.

Aerobic capacity and future cardiovascular risk in Indian community from a low-income area in Cauca, Colombia

Background

Several studies indicates that children’s aerobic capacity levels are predictors of the future risk of non-communicable diseases. Therefore, the aim of this study was to establish the proportion of subjects whose aerobic capacity is indicative of future cardiovascular risk in Indian-Nasa community from a low-income area in Cauca, Colombia.

Methods

We performed a cross-sectional analysis of morphological component (height, weight, body mass index (BMI), waist circumference, triceps skinfold, subscapular skinfold, and body fat percent [BF%]), and the cardiorespiratory component (course-navette 20 m, shuttle run test and estimation of maximal oxygen consumption by indirect VO₂max) from 576 participants (319 boys and 257 girls) aged 10 to 17.9 years, using the standardized FUPRECOL test battery.

Results

We showed that the boys performed better than the girls in cardiorespiratory fitness. The proportion of subjects with an aerobic capacity indicative of future cardiovascular risk was 7.3%. By sex, 3.8% of boys and 11.7% of girls (X²p = 0.001) displayed an unhealthy aerobic capacity in this study.

Conclusion

The findings of this study that provide the first data on aerobic capacity health for Colombian Nasa Indian children and adolescents aged 10–17.9 years. Although the known loss of aerobic capacity is a serious consequence of the future risk of non-communicable diseases, the deterioration of physical fitness deserves increased attention among indigenous population.

Physical fitness and anthropometric normative values among Colombian-Indian schoolchildren

Background

Substantial evidence indicates that children’s physical fitness levels are markers of their lifestyles and their cardio-metabolic health profile and are predictors of the future risk of chronic diseases such as obesity, cardiometabolic disease, skeletal health and mental health. However, fitness reference values for ethnic children and adolescents have not been published in a Latin-American population. Therefore, the aim of the study was to provide sex- and age-specific physical fitness and anthropometric reference standards among Colombian-Indian schoolchildren.

Methods

A sample of 576 participants (319 boys and 257 girls) aged 10 to 17 years old was assessed using the FUPRECOL test battery. Four components of physical fitness were measured: 1) morphological component: height, weight, body mass index (BMI), waist circumference (WC), triceps skinfold, subscapular skinfold, and body fat (%); 2) musculoskeletal component: handgrip and standing long jump test; 3) motor component: speed/agility test (4 × 10 m shuttle run); and 4) cardiorespiratory component: course-navette 20 m, shuttle run test and estimation of maximal oxygen consumption by VO₂max indirect. Centile smoothed curves for the 3^rd, 10^th, 25^th, 50^th, 75^th, 90^th and 97^th percentiles were calculated using Cole’s LMS method.

Results

Our results show that weight, height and BMI in each age group were higher in boys than in girls. In each groups, age showed a significant effect for BMI and WC. Boys showed better than girls in cardiorespiratory fitness, lower- and upper-limb strength and speed/agility and girls performed better in low back flexibility.

Conclusion

Our results provide for the first time sex- and age-specific physical fitness and anthropometric reference values for Colombian Nasa Indian children and adolescents aged 10–17.9 years.

Association between Body Mass Index, Waist-to-Height Ratio and Adiposity in Children: A Systematic Review and Meta-Analysis

Obesity is defined as an abnormal or excessive fat accumulation that may impair health. Dual-energy X-ray absorptiometry (DEXA) has been suggested as the gold standard to define obesity, but because its use is complex and expensive, anthropometric measures such as body mass index (BMI) or the waist-to-height ratio (WtHr) have been used as alternatives. The aim of this study was to review the published literature and investigate the correlation of BMI and WtHr with body fat (BF) measured by DEXA in pediatric populations. References were sought in PubMed/Medline and Embase datasets. Five original articles, published between 2013 and 2015, were finally included in this review. Their sample size ranged from 83 to 5355, and the age of participants ranged from 4.9 to 19 years old. The most frequently reported association measurements were the coefficients of determination (R²), followed by correlation coefficients and least-squares regression coefficients. BF measured by DEXA was strongly correlated with both BMI (R² ranging from 0.32 to 0.91) and WtHr (R² ranging from 0.49 to 0.73). Thus, either BMI or WtHr may be useful to define obesity when more sophisticated techniques are not available. Our systematic review of the available literature found that neither index demonstrated superiority in assessing obesity in children.

Joint Association of Screen Time and Physical Activity with Cardiometabolic Risk Factors in a National Sample of Iranian Adolescents: The CASPIANIII Study

Metabolic syndrome (MetS) and its contributing factors are considered important health problems in the pediatric age group. This study was designed to assess the joint association of ST and PA with cardiometabolic risk factors among Iranian adolescents. A representative sample of 5625 (50.2% boys) school students with a mean age of 14.73 (SD: 2.41) were selected through multistage random cluster sampling method from urban and rural areas of 27 provinces in Iran. ST and PA were assessed by self-administered validated questionnaires. Anthropometric measures (height, weight and waist circumference (WC)) and MetS components (abdominal obesity, elevated blood pressure (BP), low high-density lipoprotein cholesterol (HDL-C), elevated triglycerides (TG) and high fasting blood sugar (FBG)) were measured according to standardized protocols. MetS was defined according to the Adult Treatment Panel III criteria modified for the pediatric age group. Moreover, elevated total cholesterol (TC), elevated low-density lipoprotein cholesterol (LDL-C), and generalized obesity were considered as other cardiometabolic risk factors. Students with high ST levels had significantly higher body mass index z-score (BMI z-score), WC, TG, LDL-C, and BP as well as lower HDL-C level; whereas those with high PA levels had significantly higher HDL-C levels as well as lower BMI z-score, TC, and BP. Adolescents with low PA/ high ST levels had significantly higher BMI, WC, LDL-C levels, as well as higher SBP and DBP compared to their other counterparts. In Multivariate model, joint effect of low PA/ high ST (compared to the high PA/low ST group) increased the odds of overweight, abdominal obesity and low HDL-C and decreased the odds of elevated TC. The findings of this study showed that joint association of high ST and low PA have direct association with abdominal obesity, overweight and low HDL-C and indirect association with elevated TC.

A Systematic Review on the Prevalence of Overweight and Obesity, in Iranian Children and Adolescents

Context

Obesity has now become a common health problem worldwide. To gain insight into the epidemiology of the problem in Iran, we systematically reviewed all available studies on the prevalence of overweight and obesity in the Iranian pediatric population.

Evidence Acquisition

We systematically searched PubMed, ISI, SCOPUS, as well as Iranmedex, Irandoc, and Scientific Information Database (SID) databases.All studies on mean and standard deviation or percentile categories of BMI, WC, WHR, or WHtR or prevalence of obesity/overweight in Iranian child and adolescence, were performed from January 1990 to the end of December 2013. Refining processes were conducted by two independent reviewers. Quality assessment and data extraction followed based on validated form. As, these data were heterogeneous, meta-analysis was not performed.

Results

From 3253 records, through three refining steps, 129 articles were found related to our study. In Iran, national studies are limited and nearly there is no comprehensive study for sub-national trends. Different age and sex groups had large variations in the prevalence of obesity and overweight (from 1% up to 16.1% and from 4.4% up to 42.3% respectively for obesity and overweight).

Conclusions

Related data are very scattered or limited to some specific subgroups in some living areas. For comparing, aggregating, and imputing the information we need more modern practical statistical methods.

A Systematic Review of Studies on Blood Pressure in Iranian Pediatric Population: First Report From the Middle East and North Africa

Context:

Blood pressure (BP) tracks from childhood to adulthood, and has ethnic variations. Therefore, it is important to assess the situation of pediatric BP in different populations. This study aims to systematically review the studies conducted on BP in Iranian children and adolescents.

Evidence Acquisition:

We conducted a systematic review on published and national data about pediatric BP in Iran, our search was conducted in Pub Med, Medline, ISI, and Scopus, as well as in national databases including Scientific Information database (SID), IranMedex and Irandoc from 1990 to 2014.

Results:

We found 1373 records in the primary search including 840 from international and 533 from national databases. After selection and quality assessment phases, data were extracted from 36 papers and four national data sources. Mean systolic BP (SBP) varied from 90.1 ± 14 mmHg (95% CI 89.25, 90.94) to 120.2 ± 12.3 (118.98, 121.41) mmHg, and for diastolic BP (DBP) from 50.7 ± 11.4 (50.01, 51.38) to 79.2 ± 12.3 (77.95, 80.44) mmHg. The frequency of elevated BP had large variation in sub-national studies with rates as low as 0.4% (0.009, 1.98) for high SBP and as high as 24.1% (20.8, 27.67) for high DBP. At national level, three surveys reported slightly raised rates of elevated BP from 2009 to 2012.

Conclusions:

The findings provide practical information on BP levels in Iranian pediatric population. Although differences exist on the findings of various studies, this review underscores the necessity of tracking BP from childhood, and implementing interventions for primordial prevention of hypertension.

Reliability of Health-Related Physical Fitness Tests among Colombian Children and Adolescents: The FUPRECOL Study

Substantial evidence indicates that youth physical fitness levels are an important marker of lifestyle and cardio-metabolic health profiles and predict future risk of chronic diseases. The reliability physical fitness tests have not been explored in Latino-American youth population. This study’s aim was to examine the reliability of health-related physical fitness tests that were used in the Colombian health promotion “Fuprecol study”. Participants were 229 Colombian youth (boys n = 124 and girls n = 105) aged 9 to 17.9 years old. Five components of health-related physical fitness were measured: 1) morphological component: height, weight, body mass index (BMI), waist circumference, triceps skinfold, subscapular skinfold, and body fat (%) via impedance; 2) musculoskeletal component: handgrip and standing long jump test; 3) motor component: speed/agility test (4x10 m shuttle run); 4) flexibility component (hamstring and lumbar extensibility, sit-and-reach test); 5) cardiorespiratory component: 20-meter shuttle-run test (SRT) to estimate maximal oxygen consumption. The tests were performed two times, 1 week apart on the same day of the week, except for the SRT which was performed only once. Intra-observer technical errors of measurement (TEMs) and inter-rater (reliability) were assessed in the morphological component. Reliability for the Musculoskeletal, motor and cardiorespiratory fitness components was examined using Bland–Altman tests. For the morphological component, TEMs were small and reliability was greater than 95% of all cases. For the musculoskeletal, motor, flexibility and cardiorespiratory components, we found adequate reliability patterns in terms of systematic errors (bias) and random error (95% limits of agreement). When the fitness assessments were performed twice, the systematic error was nearly 0 for all tests, except for the sit and reach (mean difference: -1.03% [95% CI = -4.35% to -2.28%]. The results from this study indicate that the “Fuprecol study” health-related physical fitness battery, administered by physical education teachers, was reliable for measuring health-related components of fitness in children and adolescents aged 9–17.9 years old in a school setting in Colombia.

Body fat indices for identifying risk of hypertension in Indian children

BACKGROUND

High adiposity is major risk factor for hypertension. Various anthropometric indices are used to assess excess fatness.

OBJECTIVES

(1) To examine relationship of body mass index (BMI), waist circumference (WC), waist to height ratio (WHtR), triceps skin fold thickness (TSFT) and wrist measurements with blood pressure in children and adolescents 2) to suggest age- and gender-specific cutoffs for these indices in Indian children.

METHODS

Cross-sectional school-based study on a random sample of 6380 children (6-18 yr old, 3501 boys) from five major cities in India. Height, weight, waist and wrist circumference, TSFT, and blood pressure were recorded. Children with systolic blood pressure (BP) and/or Diastolic BP >95th percentile were classified as hypertensive.

RESULTS

Prevalence of overweight and obesity was 23.5% and 9.7%, respectively. Hypertension was observed in 5.6%. Multiple logistic regression (adjustments: age, gender) indicated double risk of hypertension for overweight and 7 times higher odds for obese than normal-weight children. Children with TSFT >95th centile for US children showed three times risk and with TSFT from 85th to 95th double risk of hypertension. Higher WC and WHtR exhibited 1.5 times risk and larger Wrist 1.3 times higher risk of hypertension (P<0.001). Receiver operating curve (ROC) analysis provided age-gender specific cut offs for the five indices to detect the risk of high BP. Area under ROC curves (AUC) for five indices were similar and greater in older age groups indicating equal sensitivity and specificity. Conclusion: Using age- and gender-specific cutoffs for BMI, TSFT, WC or WHtR may offer putative markers for early detection of hypertension.

CONCLUSION

Using age- and gender-specific cutoffs for BMI, TSFT, WC or WHtR may offer putative markers for early detection of hypertension.

An overview on the successes, challenges and future perspective of a national school-based surveillance program: the CASPIAN study

The Childhood and Adolescence Surveillance and PreventIon of Adult Non-communicable disease (CASPIAN) study is implemented in the Islamic Republic of Iran from 2003. The aim of this national school- based surveillance program was to provide accurate data of regular surveys of this program to be reviewing methodology, protocols, data collection and questionnaires of these surveys. Information was obtained from articles and books were published from CASPIAN studies. The CASPIAN studies were repeated every two years, with blood sampling for biochemical factors every four years. Methods and questionnaires of all surveys were similar at their core level and some optional factors added in different surveys. The results of CASPIAN studies represent the public health of Iranian children and adolescents that are useful for policy makers and based on them, intervention programs can set in national and sub-national level.

Waist Circumference, Waist-to-Height Ratio and Body Mass Index of Thai Children: Secular Changes and Updated Reference Standards

BACKGROUND

The prevalence of obesity in pediatric age group has been increasing globally. Body mass index (BMI), waist circumference (WC) and waist-to-height ratio (WHtR) are commonly used to define obesity. The cut-off references for these parameters vary between racial and ethnic groups. We aimed to measure the secular changes and update the reference standards for these three parameters for Thai children in this study.

MATERIALS AND METHODS

We completed a cross-sectional survey of 3,885 school children 6.0-12.99 y of age in Ongkharak district of central Thailand during May to June 2013. Weight, height and WC were recorded by trained staff using sensitive and calibrated instruments. BMI and WHtR were calculated by standard formulae. The summary estimates were described by gender and whole year age groups. Age and gender specific smoothened percentile curves were created by using least mean squares method. The data was compared with that from a 2008 cohort from the same area.

RESULTS

Age and gender specific percentile data and curves of WC, WHtR and BMI have been provided for Thai children. BMI and WC increased but WHtR changed relatively little with age in both genders. In comparison to 2008, WC and WHtR have increased consistently across all age groups and both genders. The 75th percentile for WHtR corresponded closely to 0.50 in both genders which has been the suggested cut-off.

CONCLUSION

Since 2008, there have been significant increase in WC and WHtR across all age groups and in both genders in Thai children. These indicate increasing prevalence of central obesity and upcoming cardio-metabolic health problems. This needs to be tackled urgently by creating awareness and promotion of healthy diets and physical activities in school children. WC and WHtR should be routinely measured in paediatric examination for early diagnosis of central obesity.

Is air quality index associated with cardiometabolic risk factors in adolescents? The CASPIAN-III Study

OBJECTIVE

This study aims to evaluate the association of air quality index (AQI) with cardiometabolic risk factors in a nationally representative sample of healthy adolescents.

METHODS

This nationwide survey was conducted among a stratified multi-stage probability sample of students, aged 10-18 years, from 27 provinces of Iran. Those students with history of any acute or chronic diseases, any medication use, as well as active or passive smoking were not included to the current study. Dietary and physical activity habits were documented by valid questionnaires. Physical examination and blood sampling were conducted under standard protocols. AQI data were obtained from air pollution monitoring sites from the entire country by considering air pollutants concentration, which includes all provincial counties containing different clusters.

RESULTS

The study participants consisted of 1413 students (48.8% boys) with a mean (SD) age of 14.81±2.48 years. The mean AQI level was 285.37±30.11 at national levels. After adjustment for confounding factors including age, sex, and anthropometric measures, as well as for dietary and physical activity habits, multiple linear regressions based on correlation of coefficients of the AQI with cardiometabolic risk factors showed significant positive correlations of AQI with systolic blood pressure, fasting blood glucose, total cholesterol, LDL-cholesterol, and triglycerides, as well as significant negative correlations with HDL-cholesterol. After adjustment for abovementioned confounding factors, binary logistic regressions analyses showed that AQI increased the risk of abnormal levels of some risk factors as elevated levels of systolic blood pressure, total cholesterol, and triglycerides.

CONCLUSION

The associations of low air quality with some cardiometabolic factors in the current survey, although not strong, might be considered as an evidence of the adverse cardiometabolic consequences of exposure to air pollutants in the pediatric age group, and predisposing them to earlier development of non-communicable diseases.

Abdominal obesity and serum adiponectin complexes among population-based elementary school children in Japan: a cross-sectional study

Background

There are a limited number of studies regarding the association between abdominal obesity and serum adiponectin complexes (high, medium, and low molecular weight adiponectins) among population-based elementary school children, especially in Japan, where blood collection is not usually performed during annual health examinations of school children. The aim of the present study was to investigate the relationship between abdominal obesity and serum adiponectin complexes among population-based elementary school children in Japan.

Methods

Subjects were all the fourth-grade school children (9 or 10 years of age) in the town of Ina during 2005–2008 (N = 1675). The height, weight, percent body fat, and waist circumference (WC) of each subject were measured. Blood samples were drawn from subjects to measure adiponectin isoform values. Childhood abdominal obesity was defined as “a waist-to-height ratio greater than or equal to 0.5” or “a WC greater than or equal to 75 cm”. The Wilcoxon rank-sum test and the logistic regression model were used to analyze the association between abdominal obesity and each adiponectin isoform value.

Results

Data from 1654 subjects (846 boys and 808 girls) were analyzed. Adiponectin complexes were lower in the abdominal obesity group than in the non-abdominal obesity group regardless of sex. Abdominal obesity significantly increased the odds ratio (OR) for each adiponectin isoform level less than or equal to the median value in boys; the OR (95% confidence interval [CI]) was 2.50 (1.59-3.92) for high molecular weight adiponectin (HMW-adn), 2.47 (1.57-3.88) for medium molecular weight adiponectin (MMW-adn), and 1.75 (1.13-2.70) for low molecular weight adiponectin (LMW-adn). In girls, the OR (95% CI) was 1.95 (1.18-3.21) for HMW-adn, 1.40 (0.86-2.28) for MMW-adn, and 1.06 (0.65-1.70) for LMW-adn.

Conclusions

Abdominal obesity was associated with lower adiponectin complexes and the influence of abdominal obesity varied by adiponectin isoform. Furthermore, the impact of abdominal obesity was larger in boys than in girls. The present study results suggest that prevention of abdominal obesity could contribute to the prevention of lower adiponectin levels, especially in boys.

Different waist circumference measurements and prediction of cardiovascular risk factors and metabolic syndrome in children

SUMMARY

OBJECTIVE

To compare the effectiveness of three waist circumference (WC) measurement sites to predict cardiovascular risk factors and metabolic syndrome (MS) in Brazilian children.

METHODS

187 children (mean age = 9.9 ± 0.7 years) were evaluated for weight, height, WC at three different sites: midpoint between the lower rib and iliac crest (WC1), umbilicus (WC2), and narrowest waist (WC3). Skinfolds (triceps and subscapular) and blood pressure were also measured. Analyses for triglycerides, HDL-C and glucose were carried out in 141 children.

RESULTS

For boys, the most accurate predictor of overweight and obesity (from body mass index, BMI) and low HDL-C levels was WC3, and for high percentage of body fat (from skinfolds) was WC1. For girls, WC2 was the most accurate predictor of MS, and hypertriglyceridemia, and for overweight and obesity, high body fat percentage, and low HDL-C levels, WC3 was the best predictor. WC1 was the most accurate in the prediction of high blood pressure.

CONCLUSIONS

Each WC measurement site was accurate in predicting cardiovascular risk factors and MS. However, our results indicate that WC3 was the best predictor of cardiovascular risk factors and MS in boys and girls.

The correlates of body composition with heart rate recovery after step test: an exploratory study of Malaysian adolescents

BACKGROUND

In adults, heart rate recovery is a predictor of mortality, while in adolescents it is associated with cardio-metabolic risk factors. The aim of this study was to examine the relationship between body composition measures and heart rate recovery (HRR) after step test in Malaysian secondary school students.

METHODS

In the Malaysian Health and Adolescents Longitudinal Research Team (MyHEART) study, 1071 healthy secondary school students, aged 13 years old, participated in the step test. Parameters for body composition measures were body mass index z-score, body fat percentage, waist circumference, and waist height ratio. The step test was conducted by using a modified Harvard step test. Heart rate recovery of 1 minute (HRR1min) and heart rate recovery of 2 minutes (HRR2min) were calculated by the difference between the peak pulse rate during exercise and the resting pulse rate at 1 and 2 minutes, respectively. Analysis was done separately based on gender. Pearson correlation analysis was used to determine the association between the HRR parameters with body composition measures, while multiple regression analysis was used to determine which body composition measures was the strongest predictor for HRR.

RESULTS

For both gender groups, all body composition measures were inversely correlated with HRR1min. In girls, all body composition measures were inversely correlated with HRR2min, while in boys all body composition measures, except BMI z-score, were associated with HRR2min. In multiple regression, only waist circumference was inversely associated with HRR2min (p=0.024) in boys, while in girls it was body fat percentage for HRR2min (p=0.008).

CONCLUSION

There was an inverse association between body composition measurements and HRR among apparently healthy adolescents. Therefore, it is important to identify cardio-metabolic risk factors in adolescent as an early prevention of consequent adulthood morbidity. This reiterates the importance of healthy living which should start from young.

Duration of breast-feeding and cardiovascular risk factors among Iranian children and adolescents: the CASPIAN III study

OBJECTIVES

Studies examining the relationship between breast-feeding (BF) duration and cardiovascular disease (CVD) risk factors have reached contradictory results. This study aims to investigate the relationship between BF duration and CVD risk factors in adolescents.

METHODS

This national population-based study was conducted among 5258 Iranian students, ages 10 to 18 y living in central cities of 27 provinces of Iran. Association was examined between duration of BF and adolescent blood pressure, overweight, obesity, and fasting blood glucose and lipid profiles. Analyses were adjusted for potential confounders.

RESULTS

Low birth weight was less frequent in the longer than in the shorter BF duration categories (P < 0.0001). Number of children was lower in individuals with longer BF duration (P = 0.01). Individuals with longer BF duration used more homemade food than those with shorter BF duration (P < 0.0001). Means of total cholesterol and systolic blood pressure were lower in participants with the longest BF period compared with those with the shortest BF duration; this difference was marginally significant (P = 0.06). No significant association was found between BF duration and CVD risk factors in logistic regression after adjustment for potential confounders.

CONCLUSIONS

Although the long-term benefits of BF on preventing CVDs are well documented, controversies exist as to the association of BF duration with such beneficial effects. In this study, there was no substantial evidence that longer BF duration was protective against CVD risk factors among adolescents. More prospective studies are recommended to clarify this association.

Waist circumference-to-height ratio predicts adiposity better than body mass index in children and adolescents

OBJECTIVE

Body mass index (BMI) is the surrogate measure of adiposity most commonly employed in children and adults. Waist circumference (WC) and the waist circumference-to-height ratio (WCHt) have been proposed as markers of adiposity-related morbidity in children. However, no study to date has compared WCHt, WC, BMI and skinfolds thickness for their ability to detect body adiposity.

AIM

To compare WCHt, WC, BMI and skinfolds for their accuracy in predicting percent body fat (PBF), percent trunk fat (PTF) and fat mass index (FMI) in a large sample of children and adolescents.

DESIGN, SETTING AND PARTICIPANTS

We studied 2339 children and adolescents aged 8-18 years from the US National Health and Nutrition Examination Survey 2003/2004. Body fat was measured using dual-energy X-ray absorptiometry. Multivariable regression splines were used to model the association between PBF, PTF, FMI and the predictors of interest.

RESULTS

WCHt alone explained 64% of PBF variance as compared with 31% for WC, 32% for BMI and 72% for the sum of triceps and subscapular skinfolds (SF2) (P<0.001 for all). When age and gender were added to the predictors, the explained variance increased to 80% for the WCHt model, 72% for the WC model, 68% for the BMI model and 84% for the SF2 model. There was no practical advantage to add the ethnic group as further predictor. Similar relationships were observed with PTF and FMI.

CONCLUSIONS

WCHt is better than WC and BMI at predicting adiposity in children and adolescents. It can be a useful surrogate of body adiposity when skinfold measurements are not available.

Metabolic Syndrome and Cardiovascular Risk Factors in a National Sample of Adolescent Population in the Middle East and North Africa: The CASPIAN III Study

Objective. The present study was designed to investigate the prevalence of different combinations of the metabolic syndrome (MetS) risk factors among a nationally representative sample of adolescents in the Middle East and North Africa (MENA). Methods. The study sample, obtained as part of the third study of the school-based surveillance system entitled CASPIAN III, was representative of the Iranian adolescent population aged from 10 to 18 years. The prevalence of different components of MetS was studied and their discriminative value was assessed by receiver operating characteristic (ROC) curve analysis. Results. The study participants consisted of 5738 students (2875 girls) with mean age of 14.7 ± 2.4 years) living in 23 provinces in Iran; 17.4% of participants were underweight and 17.7% were overweight or obese. Based on the criteria of the International Diabetes Federation for the adolescent age group, 24.2% of participants had one risk factor, 8.0% had two, 2.1% had three, and 0.3% had all the four components of MetS. Low HDL-C was the most common component (43.2% among the overweight/obese versus 34.9% of the normal-weight participants), whereas high blood pressure was the least common component. The prevalence of MetS was 15.4% in the overweight/obese participants, the corresponding figure was 1.8% for the normal-weight students, and 2.5% in the whole population studied. Overweight/obese subjects had a 9.68 increased odds of (95% CI: 6.65-14.09) the MetS compared to their normal-weight counterparts. For all the three risk factors, AUC ranged between 0.84 and 0.88, 0.83 and 0.87, and 0.86 and 0.89 in waist circumference, abdominal obesity, and BMI for boys and between 0.78 and 0.97, 0.67 and 0.93, and 0.82 and 0.96 for girls, respectively. Conclusion. The findings from this study provide alarming evidence-based data on the considerable prevalence of obesity, MetS, and CVD risk factors in the adolescent age group. These results are confirmatory evidence for the necessity of primordial/primary prevention of noncommunicable disease should be considered as a health priority in communities facing a double burden of nutritional disorders.

Dyslipidemia without obesity in indigenous Argentinean children living at high altitude

OBJECTIVES

To compare the prevalence of cardiovascular disease risk factors in Indian children from San Antonio de los Cobres (SAC) and children from Buenos Aires (BA), and to examine body mass index (BMI), waist circumference (WC), and WC/height as predictors of dyslipidemia in both groups.

STUDY DESIGN

Data were collected cross-sectionally from BMI, WC, blood pressure, Tanner scale, glucose, lipids, and insulin. Dyslipidemia was defined by the National Cholesterol Education Program and American Heart Association.

RESULTS

The mean ages were 10.6 ± 3.0 and 9.5 ± 2.0 years in SAC vs BA children. Of the 330 SAC children, 15 (4.5%) were overweight and 12 (3.6%) obese, and of the 603 BA, 97 (16.1%) were overweight and 82 (13.6%) obese per Centers for Disease Control. There was a significantly higher prevalence of high triglycerides (28.8% vs 3.5%) and low high-density lipoprotein cholesterol (30.0% vs 5.5%) in SAC vs BA children. The areas under the receiver operating characteristic curve in predicting high triglycerides were BMI = 0.55 (95% CI, 0.48-0.62; P = .15) in SAC and BMI = 0.65 (95% CI, 0.52-0.77; P = .02) in BA children. Similar results from the areas under the receiver operating characteristic curve were obtained when low high-density lipoprotein cholesterol was used, indicating that BMI was not a significant predictor for dyslipidemia in SAC children. When BMI was replaced by WC and WC/height, results were similar.

CONCLUSIONS

Anthropometric markers were not an acceptable predictor for National Cholesterol Education Program cutoffs for dyslipidemia in SAC children. Longitudinal studies should determine if SAC children are at high risk for cardiovascular diseases because of genetic background.

Waist circumference, waist-hip ratio and waist-height ratio percentiles and central obesity among Pakistani children aged five to twelve years

Background

Central obesity has been associated with the risk of cardiovascular and metabolic disease in children and anthropometric indices predictive of central obesity include waist circumference (WC), waist-hip ratio (WHR) and waist-height ratio (WHtR). South Asian children have higher body fat distribution in the trunk region but the literature regarding WC and related indices is scarce in this region. The study was aimed to provide age- and gender-specific WC, WHR and WHtR smoothed percentiles, and to explore prevalence and correlates of central obesity, among Pakistani children aged five to twelve years.

Methods

A population-based cross-sectional study was conducted with a representative multistage random cluster sample of 1860 primary school children aged five to twelve years in Lahore, Pakistan. Smoothed percentile curves were constructed for WC, WHR and WHtR by the LMS method. Central obesity was defined as having both age- and gender-specific WC percentile ≥90^th and WHtR ≥0.5. Chi-square test was used as the test of trend. Multivariate logistic regression was used to quantify the independent predictors of central obesity and adjusted odds ratios (aOR) with 95% CI were obtained. Linear regression was used to explore the independent determinants of WC and WHtR. Statistical significance was considered at P < 0.05.

Results

First ever age- and gender-specific smoothed WC, WHR and WHtR reference curves for Pakistani children aged five to twelve years are presented. WC increased with age among both boys and girls. Fiftieth WC percentile curves for Pakistani children were higher as compared to those for Hong Kong and British children, and were lower as compared to those for Iranian, German and Swiss children. WHR showed a plateau pattern among boys while plateau among girls until nine years of age and decreased afterwards. WHtR was age-independent among both boys and girls, and WHtR cut-off of ≥0.5 for defining central obesity corresponded to 85^th WHtR percentile irrespective of age and gender. Twelve percent children (95% CI 10.1-13.0) had a WC ≥90^th percentile and 16.5% children (95% CI 14.7-18.1) had a WHtR ≥0.5 while 11% children (95% CI 8.9-11.6) had both WC ≥90^th percentile and WHtR ≥0.5. Significant predictors of central obesity included higher grade, urban area with high socioeconomic status (SES), high-income neighborhood and higher parental education. Children studying in higher grade (aOR 5.11, 95% CI 1.76-14.85) and those living in urban area with high SES (aOR 82.34, 95% CI 15.76-430.31) showed a significant independent association. Urban area with high SES and higher parental education showed a significant independent association with higher WC and higher WHtR while higher grade showed a significant independent association with higher WC.

Conclusions

Comprehensive worldwide reference values are needed to define central obesity and the present study is the first one to report anthropometric indices predictive of central obesity for Pakistani school-aged children. Eleven percent children were centrally obese and strong predictors included higher grade, urban area with high SES and higher parental education. These findings support the need for developing a National strategy for childhood obesity and implementing targeted interventions, prioritizing the higher social class and involving communities.

Reference curves for BMI, waist circumference and waist-to-height ratio for Azorean adolescents (Portugal)

Objective

There are no percentile curves for BMI, waist circumference (WC) or waist-to-height ratio (WHtR) available for Portuguese children and adolescents. The purpose of the present study was to develop age- and sex-specific BMI, WC and WHtR percentile curves for a representative sample of adolescents living in the Portuguese islands of Azores, one of the poorest regions of Europe, and to compare them with those from other countries.

Design

Cross-sectional school-based study. Weight, height and WC were objectively measured according to standard procedures. Smoothed percentile curves were estimated using Cole's LMS method.

Setting

Azores, Portugal.

Subjects

Proportionate stratified random sample of 1500 adolescents, aged 15–18 years.

Results

Results showed some sex differences in the shape of the BMI curves: in girls, the upper percentile values tend to decrease by the age of 16 and 17 years; whereas in boys, the upper percentiles tend to be flat between 15 and 16 years and then increase until the age of 18 years. In both sexes, the upper percentile values of both WC and WHtR decreased slightly by the age of 16 years and then increased steeply. In both sexes, the Azorean values for the 50th and 90th WC percentiles were higher than those reported for adolescents from the majority of other countries.

Conclusions

The reference curves presented herein provide baseline data for the long-term surveillance of Azorean adolescents, as well as for national and international comparisons.

Do the prevalence and components of metabolic syndrome differ among different ethnic groups? A cross-sectional study among obese Malaysian adolescents

OBJECTIVE

The aim of this study was to determine the prevalence of metabolic syndrome and the most common combination of cardiometabolic disorders among different ethnic groups of obese adolescents in Malaysia.

RESEARCH DESIGN AND METHODS

A cross-sectional study among 335 obese adolescent boys and girls aged 12-18 years from 10 randomly selected schools was conducted. After recording blood pressure and waist circumference (WC), a fasting blood sample was obtained and analyzed for glucose and lipids. Metabolic syndrome was diagnosed on the basis of adolescent metabolic syndrome criteria specified by National Cholesterol Education Program Adult Treatment Panel III if three of the five risk factors--hypertriglyceridemia, hyperglycemia, hypertension, low high-density lipoprotein C, and increased WC--were present. The prevalence among different ethnic groups was analyzed.

RESULTS

The obesity rate among adolescents was 8.4%, and nearly one-third of the obese adolescents had metabolic syndrome. More than 90% of obese adolescents had at least one metabolic abnormality. Metabolic syndrome was more prevalent among obese boys (40.2%) compared to obese girls (17%). Boys had significantly higher mean WC and triglycerides and lower HDL-C (P value 0.0001). Increased WC and triglycerides and high blood pressure comprised the most prevalent (34.3%) risk factor combination followed by WC, low HDL, and high blood pressure (22.5%). Over all, Indians had the highest prevalence of metabolic syndrome (36.4%), followed by Chinese (33.8%) and Malays (27.4%). Elevated triglyceride levels were more prevalent among Chinese, hypertension among Malays, and the other three abnormalities among Indians.

CONCLUSION

Indians had the highest prevalence of metabolic syndrome. Increased WC and triglycerides and high blood pressure comprised the most prevalent risk factor combination.

Indicadores antropométricos de sobrepeso e obesidade como preditores de alterações lipídicas em adolescentes

OBJETIVO: Identificar o poder preditivo dos indicadores antropométricos de sobrepeso e obesidade para alterações lipídicas em adolescentes. MÉTODOS: Estudo transversal envolvendo 660 adolescentes de 14 a 19 anos (317 rapazes; 343 moças). Foram considerados os seguintes indicadores antropométricos: índice de massa corpórea (IMC), circunferência da cintura, razão cintura/estatura e índice de conicidade. As alterações lipídicas foram caracterizadas pelo colesterol total (CT) superior a 170mg/dL e lipoproteínas de alta densidade (HDL-C) inferiores a 45mg/dL. Para identificar os preditores das alterações lipídicas, adotou-se a análise das curvas Receiver Operating Characteristics (ROC). Foram calculados os pontos de corte com suas respectivas sensibilidades e especificidades e, posteriormente, as razões de prevalência entre os indicadores antropométricos e os desfechos investigados. RESULTADOS: As áreas sob as curvas ROC (intervalo de confiança de 95%) para CT elevado nos rapazes e respectivos pontos de corte foram: IMC de 0,74 (0,65-0,83) e 21,7kg/m²; circunferência de cintura de 0,73 (0,65-0,82) e 74cm; razão cintura/estatura de 0,72 (0,63-0,81) e 0,4; índice de conicidade de 0,60 (0,50-0,69) e 1,1. Para a predição dos baixos níveis de HDL-C, as áreas da curva ROC e os pontos de corte foram: IMC dos rapazes de 0,58 (0,52-0,64) e 20,7kg/m²; para as moças de 0,61 (0,53-0,69) e 20,8kg/m²; circunferência de cintura, rapazes com 0,57 (0,50-0,63) e 73,3cm, moças com 0,63 (0,55-0,72) e 71,5cm; razão cintura/estatura (C/Est), rapazes de 0,58 (0,52-0,65) e C/Est de 0,4, moças de 0,62 (0,54-0,70) e C/Est de 0,4; índice de conicidade, moças de 0,60 (0,51-0,68) e 1,1. CONCLUSÕES: Os indicadores antropométricos foram bons preditores de CT elevado nos rapazes e razoáveis para os baixos níveis de HDL-C para rapazes e moças.

Comparison of different anthropometric indices for identifying dyslipidemia in school children

BACKGROUND

Anthropometric indices have been associated with dyslipidemia.

OBJECTIVE

To compare the abilities of BMI, waist circumference (WC) and WC/height to identify children's dyslipidemia.

METHODS

Students 1261 (639 male) age 9.5±2.1 years. were examined for anthropometry and lipid levels. Triglycerides ≥1.69 mmol/L and high-density lipoprotein cholesterol (HDL-C) <0.91 mmol/L were considered abnormal per American Heart Association.

RESULTS

The prevalence of abnormal triglycerides was 4.1% and HDL-C 8.1%. The areas under the receiver operator curves (ROC) were: BMI=0.87, WC=0.83, and WC/height=0.84 in predicting both low HDL-C and high triglycerides. Multiple regression analyses showed that the odds ratios (OR) were highest for WC [6.5], followed by WC/height [5.4], and BMI [4.9], for dyslipidemia.

CONCLUSIONS

The results suggest that WC, WC/height, and BMI similarly predicted dyslipidemia, using ROC analyses. However, regression analyses showed that WC followed by WC/height was most predictive of dyslipidemia.

Effects of a lifestyle modification trial among phenotypically obese metabolically normal and phenotypically obese metabolically abnormal adolescents in comparison with phenotypically normal metabolically obese adolescents

This study aimed to assess the effects of a 2-month lifestyle modification trial on cardio-metabolic abnormalities and C-reactive protein (CRP) among obese adolescents with metabolic syndrome [phenotypically obese metabolically abnormal (POMA)] and obese adolescents without a cardio-metabolic disorder [phenotypically obese metabolically normal (POMN)], as well as in normal-weight adolescents with at least one cardio-metabolic disorder [phenotypically normal metabolically obese (PNMO)]. The study comprised 360 adolescents assigned in three groups of equal number of POMN, POMA and PNMO. They were enrolled in a trial consisting of aerobic activity classes, diet and behaviour modification, and were recalled after 6 months. Overall, 94.7% of participants completed the 2-month trial, and 87.3% of them returned after 6 months. The mean CRP was not significantly different between the POMA and PNMO groups, but was higher than in the POMN group. After the trial, body mass index (BMI) and waist circumference (WC) decreased in obese participants, and the mean body fat mass decreased in all groups. At 2 months, the mean total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), triglycerides (TG) and CRP decreased in the POMA and PNMO groups. After 2 and 6 months, the decrease in mean TC, LDL-C, TG, CRP and systolic blood pressure was greater in the POMA than in the POMN group. The magnitude of decrease in CRP correlated with that of BMI, WC, fat mass, TG, TC and LDL-C. Lifestyle modification programmes for primordial/primary prevention of chronic diseases would be beneficial at the population level and should not be limited to obese children.

Accuracy of simple clinical and epidemiological definitions of childhood obesity: systematic review and evidence appraisal

The optimum means of defining obesity in children is unclear, creating variation in practice, and hindering obesity surveillance, prevention and treatment. This study aimed to review evidence on the use of body mass index (BMI) and waist circumference for diagnosis of high body fat content and adverse cardiometabolic risk factors in children and adolescents. A systematic literature review was carried out and evidence appraised using the Quality Assessment of Studies of Diagnostic Accuracy in Systematic Reviews method. Literature searching began following the last systematic review of this topic (end 2001) and collected evidence in MEDLINE and EMBASE in 0- to 18-year-olds that compared the accuracy of BMI vs. waist circumference and compared BMI interpreted relative to national reference data vs. BMI interpreted relative to Cole/International Obesity Task Force international reference data. Ten studies compared diagnostic accuracy of BMI vs. waist circumference: they reported no improved identification of adverse cardiometabolic risk profiles from waist circumference over that provided by high BMI. Eight studies compared BMI with national reference data vs. the international approach: 5/8 found significantly poorer accuracy (lower sensitivity) using BMI with the international approach; 3/8 found similar sensitivity; in 7/7 studies that compared specificity this was similar. In conclusion, the present review provides no compelling evidence for use of either high waist circumference or BMI interpreted using the International Obesity Task Force approach in preference to the use of national BMI percentiles for the identification of children and adolescents with excess fatness and adverse cardiometabolic risk profile.

Anthropometric correlates of lipoprotein profile and blood pressure in high BMI African American children

OBJECTIVE

To explore the association of anthropometric indices with lipoprotein profile and blood pressure as risk factors of cardiovascular disease, in African American (AA) children.

METHODS

A cross-sectional analysis was carried out on children aged 9-13 years with BMI >85th percentile. Height, weight, waist and hip circumferences, % body fat and blood pressure [systolic (sBP) and diastolic (dBP)] were measured. Fasting plasma levels of triglycerides (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), intermediate density lipoprotein cholesterol (IDL-C) and very low-density lipoprotein cholesterol (VLDL-C) were analysed.

RESULTS

After accounting for age, gender and pubertal status of the child, multiple linear regression models showed that waist circumference and BMIz were strong predictors for lipoprotein variables. In independent analysis, waist circumference and BMI z-scores were found to be interdependently associated with TG, LDL-C:HDL-C ratio, VLDL-C and sBPz. However, for HDL-C, TG:HDL-C ratio and dBPz, waist circumference was independently and more strongly associated with these risk factors than BMI.

CONCLUSION

Waist circumference was a stronger predictor for lipoprotein variables and blood pressure in high BMI AA children than other anthropometric indices, and may be adequate as a screening test to identify children who are at increased risk for cardiovascular disease.