Evaluation of waist circumference, waist-to-hip ratio, and the conicity index as screening tools for high trunk fat mass, as measured by dual-energy X-ray absorptiometry, in children aged 3-19 y

Waist circumference as a parameter in school-based interventions to prevent overweight and obesity - a systematic review and meta-analysis

BACKGROUND

Preventing childhood obesity remains an important public health issue worldwide. Since visceral fat in particular is understood as an important risk factor for many chronic diseases, waist circumference is recommended as a measurement parameter for global obesity surveillance. This systematic review and meta-analysis focused on waist circumference as an outcome parameter for studies of school-based interventions to prevent overweight and obesity.

METHODS

A systematic literature search was conducted at the end of 2019 in nine data bases, including Medline and Embase, in order to identify relevant studies evaluating interventions in schools aimed at preventing obesity. Eligibility criteria admitted randomised and non-randomised controlled trials. After screening titles, abstracts and full texts, the data of the identified studies were systematically extracted. Risk of bias was assessed according to study type with the appropriate Cochrane Risk of Bias Tool. The review gives a qualitative overview over all included studies structured by extracted data. Separate meta-analyses were done for the outcome mean difference in change in waist circumference, measured in cm or reported as z-score value, using an inverse variance random-effects model due to study design.

RESULTS

A total of 2421 publications were screened based on titles, abstracts and full texts. Complemented by results of a former systematic literature search 44 studies were identified for inclusion, comprising a total of 39.837 participants (age range: 6 to 18 years). Nearly half of the studies were conducted in Europe, two-thirds combined diet and exercise-based interventions. Likewise two thirds of the studies were conducted as cluster-randomised trials. Most of the reported effects favoured the experimental groups, indicating the basic effectiveness of school-based measures. Based on reported data, only one third of the studies could be included in the meta-analyses. For the difference in mean change of the outcome parameter waist circumference measured in cm (95% CI), we found a pooled effect estimate of -0.95 (-1.87; -0.46). For the difference in mean change of the outcome parameter waist circumference reported as z-score value (95% CI), the pooled effect estimate was -0.10 (-0.15; -0.05). Both effect estimates were in favour of the experimental group. The overall effect sizes were small with a p-value < 0.05.

CONCLUSIONS

Pooled effect estimates were small but in favour of the experimental groups. The same applies to the majority of the effects reported in the included studies. The included cluster of randomised controlled trials demonstrated an especially sound methodological standard. The possibility of achieving larger effects in studies of preventive interventions and health promotion is limited. Schools can only realise their full potential in preventing overweight and obesity in children and adolescents if they are accompanied by measures in other areas of the obesogenic environment.

Serum glutathione peroxidase is associated with nonalcoholic fatty liver disease in children and adolescents

BACKGROUND AND AIMS

oxidative stress is an important factor in the pathophysiology of non-alcoholic fatty liver disease (NAFLD). This study aimed to compare the serum levels of malondialdehyde (MDA), glutathione peroxidase (GPx) and antioxidant micronutrients in children and adolescents with and without NAFLD.

METHODS

a cross-sectional study with patients between 8-18 years old, of both sexes. Diagnosis of NAFLD: presence of steatosis on ultrasound and absence of history of ethanol consumption and other liver diseases. Anthropometric measures, MDA, GPx, Interleukin-6, serum levels of vitamins A, C and E, selenium, zinc, and copper were evaluated.

RESULTS

eighty-nine children with mean age of 12 (3) years, 57.3 % female and 24 % with NAFLD were evaluated. Those with NAFLD had more frequent abdominal obesity (high waist-height ratio: 81.0 % x 48.5 %; p = 0.009). After logistic regression NAFLD was associated with high body mass index/age (p-adjusted = 0.021) and with reduced serum GPx (p-adjusted = 0.034). There was a positive correlation between MDA and copper (r = 0.288; p = 0.006), IL-6 (r = 0.357; p = 0.003) and a negative one with vitamin A (r = -0.270; p = 0.011).

CONCLUSIONS

oxidative stress is present in children with NAFLD and non-invasive markers such as GPx and BMI can be used in clinical practice and help in the early screening of NAFLD.

Association between ultraprocessed food consumption and excess adiposity in children and adolescents: A systematic review

Ultraprocessed foods (UPF) consumption is associated with excess adiposity in adults, but this linkage remains unclear among children and adolescents. The present systematic review sought to address this research gap. Publications up to November 2023 were retrieved from PubMed, Web of Science, and Scopus databases. Outcomes included overweight/obesity anthropometric and body composition indicators; the exposure was UPF consumption based on the NOVA classification system. The review included 23 studies (i.e., 8 cohort and 15 cross-sectional); approximately half were carried out in Brazil. Inconclusive and heterogeneous evidence exists as few cohort studies found positive/mixed associations between UPF consumption and excess adiposity in pediatric populations, whereas most cross-sectional studies reported null associations. Such inconsistencies may be attributed to underlying methodological issues, especially heterogeneity in the outcomes assessed and UPF consumption operationalization and/or categorization. Future studies should adopt longitudinal designs with sufficiently extended follow-up periods, account for relevant confounding factors, employ validated and standardized measurement tools to assess dietary exposure, ensure consistent operationalization of variables, and encompass diverse geographic contexts. Ultimately, strengthening the quality of existing research evidence may better inform current and forthcoming policy and practice interventions aimed at mitigating the increasing prevalence of overweight/obesity in childhood and across the life course.

Overview of BMI and Other Ways of Measuring and Screening for Obesity in Pediatric Patients

Despite a long history of advances in measuring body size and composition, body mass index (BMI) has remained the most commonly used clinical measure. We explore the advantages and disadvantages of using BMI and other measures to estimate adipose tissue, recognizing that no measure of body size or adiposity has fulfilled the goal of differentiating health from disease. BMI and waist circumference remain widely-used clinical screening measures for appropriate risk stratification as it relates to obesity.

Light-Intensity Physical Activity and Sedentary Behavior Are Associated With Blood Pressure Levels in Adolescents

PURPOSE

To investigate the associations between physical activity (PA) intensities, sedentary behavior (SB), and blood pressure (BP) in adolescents, according to sex.

METHOD

This cross-sectional study involved 95 male and female adolescents aged 15-18 years. Accelerometry was used to measure time spent in light-intensity PA (LPA), moderate to vigorous PA (MVPA), and vigorous PA, and SB. The BP was determined using an automated sphygmomanometer. Statistical analyses included multiple linear regression and command margins.

RESULTS

Significant associations were found between systolic BP (SBP) and time spent in LPA (B = -0.08; 95% CI, -0.15 to -0.01) and SB (B = 0.071; 95% CI, 0.004-0.138), albeit only in boys. Furthermore, an interaction was observed between time spent in SB and MVPA for SBP in boys (B = -0.002; 95% CI, -0.004 to -0.0008). The main interaction effect of increasing SBP was a combination of <75 minutes per day of MVPA and up to 600 minutes per day of SB.

CONCLUSIONS

Increased time in LPA and reduced time spent in SB during the day are associated with lower SBP in male adolescents. Additionally, the relation between SB and SBP was attenuated by MVPA. These findings provide crucial insights for PA recommendations to promote cardiovascular health in adolescents.

Association of Whole Blood Amino Acid and Acylcarnitine Metabolome with Anthropometry and IGF-I Serum Levels in Healthy Children and Adolescents in Germany

BACKGROUND

Physiological changes of blood amino acids and acylcarnitines during healthy child development are poorly studied. The LIFE (Leipziger Forschungszentrum für Zivilisationserkrankungen) Child study offers a platform with a large cohort of healthy children to investigate these dynamics. We aimed to assess the intra-person variability of 28 blood metabolites and their associations with anthropometric parameters related to growth and excess body fat.

METHODS

Concentrations of 22 amino acids (AA), 5 acylcarnitines (AC) and free carnitine of 2213 children aged between 3 months and 19 years were analyzed using liquid chromatography/tandem mass spectrometry. Values were transformed into standard deviation scores (SDS) to account for sex- and age-related variations. The stability of metabolites was assessed through the coefficient of determination. Associations with parameters for body composition and insulin-like growth factor-I (IGF-I) SDS were determined by the Pearson correlation and linear regression.

RESULTS

Our research revealed substantial within-person variation in metabolite concentrations during childhood and adolescence. Most metabolites showed a positive correlation with body composition parameters, with a notable influence of sex, pubertal status and weight group. Glycine exhibited negative associations with parameters of body fat distribution, especially in normal weight girls, overweight/obese boys and during puberty.

CONCLUSION

Blood AA and AC measurements may contribute to elucidating pathogenesis pathways of adiposity-related comorbidities, but the specific timings and conditions of development during childhood and adolescence need to be taken into consideration.

Childhood obesity is associated with a high degree of metabolic disturbance in children from Brazilian semi-arid region

Projected to impact 310 million children by the next decade, childhood obesity is linked to serious health issues like metabolic disturbance and cardiovascular diseases. This study introduces a novel approach for the integrated assessment of inflammatory, glycemic and lipid disorders in obese children in resources-limited settings and also identifies key factors contributing to these changes. Conducting a cross-sectional analysis of 231 children aged 5-12 years from public schools in Brazil's semi-arid region, the research involved collecting medical history, anthropometric measurements, and blood samples to analyze glycemic and lipid profiles, along with C-reactive protein levels. We used an adapted the Molecular Degree of Perturbation model to analyze deviations in metabolic markers from a healthy control group. Statistical analyses included Mann-Whitney and Fisher exact tests, backward logistic regression, and hierarchical cluster analysis. The study identified a direct and independent association between elevated Metabolic Disturbance Degree and both overweight and obesity in children, with significant differences in CRP, Triglycerides, and HDL levels noted between obese and healthy-weight groups. The findings highlight the critical need for early detection and comprehensive understanding of obesity-related changes to mitigate the severe health risks associated with childhood obesity.

Body Composition and Energy Expenditure in Youth With Spina Bifida: Protocol for a Multisite, Cross-Sectional Study

BACKGROUND

Obesity prevalence in youth with spina bifida is higher than in their typically developing peers. Obesity is associated with lifelong medical, psychological, and economic burdens. Successful prevention or treatment of obesity in individuals with spina bifida is compromised by (1) the lack of valid and reliable methods to identify body fat in a clinical setting and (2) limited data on energy expenditure that are necessary to provide daily caloric recommendations.

OBJECTIVE

The objectives of this study will be to develop 2 algorithms for use in youth with spina bifida in a clinical setting, one to model body fat and one to predict total daily energy expenditure. In addition, physical activity and dietary intake will be described for the sample.

METHODS

This multisite, prospective, national clinical study will enroll 232 youth with myelomeningocele aged 5 to 18 years (stratified by age and mobility). Participants will be enrolled for 1 week. Data obtained include 4 measures of body composition, up to 5 height measures, a ramped activity protocol, and a nutrition and physical activity screener. Participants will wear an accelerometer for the week. On the final study day, 2 samples of urine or saliva, which complete the doubly labeled water protocol, will be obtained. The analysis will include descriptive statistics, Bland-Altman plots, concordance correlation, and regression analysis.

RESULTS

The study received extramural federal funding in July 2019. Data collection was initiated in March 2020. As of April 2024, a total of 143 (female participants: n=76, 53.1%; male participants: n=67, 46.9%) out of 232 participants have been enrolled. Data collection is expected to continue throughout 2024. A no-cost extension until November 2025 will be requested for data analysis and dissemination of findings.

CONCLUSIONS

This study furthers previous pilot work that confirmed the acceptability and feasibility of obtaining alternate height, body composition, and energy expenditure measures. The findings from this study will enhance screening, prevention, and treatment of abnormal weight status by facilitating the accurate identification of youths' weight status category and recommendations of daily caloric needs for this population that is at higher risk of obesity. Furthermore, the findings have the potential to impact outcomes for youth diagnosed with disabilities other than spina bifida who experience similar challenges related to alterations in body composition or fat distribution or measurement challenges secondary to mobility issues or musculoskeletal problems.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/52779.

Acculturation and Health Status in the Children's Healthy Living Program in the Pacific Region

Acculturation/enculturation has been found to impact childhood health and obesity status. The objective of this study is to use cross-sectional data to examine the association between proxies of adult/caregiver acculturation/enculturation and child health status (Body Mass Index [BMI], waist circumference [WC], and acanthosis nigricans [AN]) in the U.S.-Affiliated Pacific Islands (USAPI), Alaska, and Hawai'i. Study participants were from the Children's Healthy Living (CHL) Program, an environmental intervention trial and obesity prevalence survey. Anthropometric data from 2-8 year olds and parent/caregiver questionnaires were used in this analysis. The results of this study (n = 4121) saw that those parents/caregivers who identified as traditional had children who were protected against overweight/obesity (OWOB) status and WC > 75th percentile (compared to the integrated culture identity) when adjusted for significant variables from the descriptive analysis. AN did not have a significant association with cultural classification. Future interventions in the USAPI, Alaska, and Hawai'i may want to focus efforts on parents/caregivers who associated with an integrated cultural group as an opportunity to improve health and reduce child OWOB prevalence.

Weight Gain from Birth to Adolescence and TyG Index at Age 18 Years: A Cohort Study in Northeast Brazil

BACKGROUND

Developmental models suggest that the phenotypes may arise from an immediate or mediated adaptive metabolic response of the perinatal growth. Evidence on the cumulative effects of growth and factors associated with risk of insulin resistance in adolescents is lacking.

OBJECTIVE

To investigate the association between birthweight, weight gain during infancy, childhood and adolescence and the triglyceride-glucose index in adolescents.

METHODS

This is a cohort of 217 children born at term, followed for the first six months, and reassessed at 8 and 18 years of age. The variables of interest were birthweight, postnatal growth defined as rapid postnatal growth when the weight gain from birth to six months of age was greater than 0.67 z-score, and the same criterion was used for high BMI gain from ages 6 months to 8 years, and from 8 to 18 years. Socioeconomic condition, nutritional status, practice of physical exercises and consumption of ultra-processed foods were verified. Multivariate linear regression analysis was used to verify the effect of the variables on the triglyceride-glucose index.

RESULTS

Birthweight was not associated with triglyceride-glucose index in adolescence. Rapid postnatal growth during the first 6 months, higher BMI gain from 8 to 18 years and higher waist circumference contributed significantly to explain higher triglyceride-glucose index.

CONCLUSION FOR PRACTICE

Our findings suggest that rapid postnatal growth may be one of the first signs of a higher triglyceride-glucose index in adolescence and that attention should be paid to the greater gain in body mass between childhood and adolescence for the risk of a higher triglyceride-glucose index.

Investigation of Underlying Association between Anthropometric and Cardiorespiratory Fitness Markers among Overweight and Obese Adolescents in Canada

BACKGROUND

Adolescents who experience overweight or obesity commonly persist in these conditions into adulthood, thereby elevating their vulnerability to health issues. The focus of this study is on health risk markers such as body mass index (BMI), waist circumference (WC), waist-to-height ratio (WHtR), body surface area (BSA), and cardiorespiratory fitness (CRF). The objectives include updating normative values for BMI, WC, WHtR, and BSA in Canadian adolescents, establishing cardiometabolic risk zones, and developing a composite score considering both anthropometric and CRF markers.

METHODS

Involving 1864 adolescents, the study used the LMS method to generate percentile norms, stratified by age and sex. Cardiometabolic risk zones were established for each marker based on Z-scores, and a composite score was created.

RESULTS

An increase in WC of 5.8 and 7.4 cm for boys and girls, respectively, was observed since 1981. Forward multiple regression analyses were conducted to assess the robustness and validity of the proposed model. The results indicated that the model explained nearly 90% (R2 = 0.890) of the common variance between the composite score and the retained independent variables. Moreover, the model demonstrated a mean absolute error (MAE) of approximately 6 percentiles, confirming its high precision. Furthermore, these analyses yielded key thresholds for identifying adolescents at risk: the 70th percentile for high cardiometabolic risk and the 85th percentile for very-high risk.

CONCLUSIONS

Individually, WC or WHtR seem to be better markers for evaluating cardiometabolic risk than BMI during adolescence. However, CRF showed comparable importance to anthropometric markers in determining cardiometabolic risk. The simultaneous inclusion of anthropometric and CRF markers provides a better picture of the global cardiometabolic risk in adolescents.

Effectiveness of the Walking in ScHools (WISH) Study, a peer-led walking intervention for adolescent girls: results of a cluster randomised controlled trial

BACKGROUND

Most adolescent girls fail to meet current physical activity guidelines. Physical activity behaviours track from childhood into adulthood and providing adolescent girls with opportunities to be physically active may have health benefits beyond childhood. The effects of walking interventions on adult cardiometabolic health are known, however less is understood about the potential of walking to promote physical activity in adolescents. Following the Walking In ScHools (WISH) feasibility study, this definitive trial aimed to evaluate the effectiveness of a novel, low-cost, school-based walking intervention at increasing physical activity levels of adolescent girls (aged 12-14 years).

METHODS

Female pupils were recruited from eighteen schools across the border region of Ireland and in Northern Ireland. In intervention schools (n = 9), girls aged 15-18 years, were trained as walk leaders, and led the younger pupils in 10-15 min walks before school, at break and lunch recess. All walks took place in school grounds and pupils were encouraged to participate in as many walks as possible each week. The primary outcome measure was accelerometer determined total physical activity (counts per minutes, cpm).

RESULTS

In total, 589 pupils were recruited to the study. At baseline, pupils engaged in a median (interquartile range (IQR)) 35.7 (21.2) mins moderate-vigorous physical activity (MVPA) per day and only 12% (n = 66) of participants met physical activity guidelines (60 min MVPA per day). The intervention was delivered for a mean (standard deviation (SD)) 19.9 ± 0.97 weeks. The mean post-intervention total physical activity for the intervention group was 676 cpm and 710 cpm in the control group. Post-intervention total physical activity did not statistically differ between groups when adjusted for age, body mass index z-scores and baseline physical activity (mean difference, -33.5, 95% CI = -21.2 to 88.1; p = 0.213).

CONCLUSIONS

'Scaling-up' physical activity interventions is challenging and despite a promising feasibility study, the results of this fully powered trial suggest that in this context, the WISH intervention did not increase device measured physical activity. Since the COVID-19 pandemic, school environments have changed and although pupils enjoyed the programme, attendance at walks was low, indicating that there is a need to better understand how to implement interventions within schools.

TRIAL REGISTRATION

ISRCTN; ISRCTN12847782; Registered 2nd July 2019.

Evaluating the performance of a novel anthropometric index: weight adjusted for waist-to-height ratio (W-WHR) - for predicting cardiometabolic risk among adults in Addis Ababa

OBJECTIVE

Various anthropometric indices had been proposed to predict cardiometabolic risk, yet few were validated in the African population. We evaluated the diagnostic accuracy of a novel anthropometric index-weight adjusted for waist-to-height ratio (W-WHR)-as a predictor of cardiometabolic risk among adults 18-64 years in Addis Ababa, Ethiopia; and compared its performance with other indices commonly used in the literature.

DESIGN

Cross-sectional study.

SETTING

Community-based study in Addis Ababa, Ethiopia.

PARTICIPANTS

Randomly selected adults (n=600) completed serum lipid, blood pressure, blood glucose and anthropometric measurements.

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary outcomes of interest were dyslipidaemia, hypertension and hyperglycaemia. Having at least one of the three outcomes was considered as a secondary outcome. Receiver-operating characteristic curve (ROC) used to measure the diagnostic accuracy of W-WHR and another 13 indices for predicting the primary and secondary outcomes. Optimal thresholds were determined using Youden's index.

RESULTS

W-WHR demonstrated an acceptable diagnostic accuracy (area under the curve (AUC), 95% CI) for correctly classifying dyslipidaemia (0.80, 0.76 to 0.84), hypertension (0.74, 0.70 to 0.78), hyperglycaemia (0.76, 0.70 to 0.82) and the secondary outcome of interest (0.79, 0.75 to 0.83). Depending on the outcomes, thresholds between 32.6 and 36.7 concurrently maximised sensitivity and specificity of the index. ROC analysis indicated, W-WHR (AUC=0.80), abdominal volume index (AVI) (AUC=0.78) and waist circumference (WC) (AUC=0.78) for dyslipidaemia; W-WHR (AUC=0.74) and WC (AUC=0.74) for hypertension; and waist-to-height ratio (AUC=0.80) and body roundness index (AUC=0.80) for hyperglycaemia, had the highest diagnostic accuracy. Likewise, W-WHR (AUC=0.79), AVI (AUC=0.78) and WC (AUC=0.78) had better performance for the secondary outcome. Most indices have better utility among younger than older adults, and per cent body fat had the highest diagnostic accuracy among women (AUC 0.74-0.83).

CONCLUSION

W-WHR is a useful index for predicting cardiometabolic risk, especially among young adults.

Body Composition Evaluation and Clinical Markers of Cardiometabolic Risk in Patients with Phenylketonuria

Cardiovascular diseases are the main cause of mortality worldwide. Patients with phenylketonuria (PKU) may be at increased cardiovascular risk. This review provides an overview of clinical and metabolic cardiovascular risk factors, explores the connections between body composition (including fat mass and ectopic fat) and cardiovascular risk, and examines various methods for evaluating body composition. It particularly focuses on nutritional ultrasound, given its emerging availability and practical utility in clinical settings. Possible causes of increased cardiometabolic risk in PKU are also explored, including an increased intake of carbohydrates, chronic exposure to amino acids, and characteristics of microbiota. It is important to evaluate cardiovascular risk factors and body composition in patients with PKU. We suggest systematic monitoring of body composition to develop nutritional management and hydration strategies to optimize performance within the limits of nutritional therapy.

Anthropometric indicators as discriminators of high body fat in children and adolescents with HIV: comparison with reference methods

BACKGROUND

Body fat assessment is needed in individuals with HIV. The objective was to identify the discriminatory capacity of the abdominal skinfold (ASF) tricipital skinfold (TSF), subscapular fold (SSF), calf skinfold (CSF), body adiposity index (BAI), body mass index, conicity index (IC), mid-upper arm circumference (MUAC), waist circumference (WC), perimeter of neck (PN) and waist-to-height ratio (WHtR) for high body fat in children and adolescents with HIV, compared Dual energy X-ray absorptiometry (DXA) and air displacement plethysmography (ADP).

METHODS

Descriptive study, cross - sectional study, with 65 children and adolescents with HIV by vertical transmission. Body fat was measured by DXA and ADP. Measures were measured by international standardization. The diagnostic properties for high body fat were assessed by area under the ROC curve (AUC).

RESULTS

For boys, having DXA as a reference for fat, ASF (AUC: 0.920), TSF (AUC: 0.792), SSF (AUC: 0.766), CSF (AUC: 0.866), BAI satisfactory discriminatory capacity. With ADP as the reference method, ASF (AUC: 0.920), TSF (AUC: 0.921), SSF (AUC: 0.766), CSF (AUC: 0.901), BAI (AUC: 0.756) and BMI (AUC: 0.699) presented satisfactory results. For girls, having DXA as a reference for fat, ASF (AUC: 0.838), TSF (AUC: 0.842), SSF (AUC: 0.840), CSF (AUC: 0.887), BAI (AUC: 0.846), and BMI (AUC: 0.859) presented satisfactory discriminatory capacity. Assuming ADP as a reference for fat, ASF (AUC [AUC: 0.799], TSF [AUC: 0.825], SSF [AUC: 0.767], CSF [AUC: 0.897], BAI 0.788), were satisfactory.

CONCLUSIONS

The ASF, TSF, SSF, CSF, BAI and BMI anthropometric indicators may be suggested as the most suitable for the detection of high body fat in children and adolescents with HIV.

Association between Sleep Quality and Cardiac Autonomic Modulation in Adolescents: A Cross Sectional Study

Objective  To analyze the impact of sleep quality/duration on cardiac autonomic modulation on physically active adolescents with obesity. Materials and Methods  The present cross-sectional study included 1,150 boys with a mean age of 16.6 ± 1.2 years. The assessment of cardiac functions included the frequency domain of heart rate variability (HRV; low frequency - LF; high frequency - HF; and the ratio between these bands -LF/HF -, defined as the sympathovagal balance), and each parameter was categorized as low / high . Physical activity levels and sleep quality/duration were obtained by questionnaires. Abdominal obesity was assessed and defined as waist circumference > 80 th percentile. Results  Poor sleep quality resulted in lower HF (odds ratio [OR]: 1.8; 95% confidence interval [95%CI]: 1.01-3.21]) regardless of physical activity and abdominal obesity. Moreover, the study found no association between sleep duration and HRV parameters in adolescents. Conclusion  Sleep quality, not sleep duration, reduces parasympathetic cardiac modulation apart from other factors such as physical activity and abdominal obesity in adolescents.

Novel Anthropometric Indices as Screening Tools for Obesity: A Study on Healthy Iranians

Background and Aims

Upper body fat distribution is more related to cardiometabolic diseases than central obesity. Neck circumference (NC) and neck-to-height ratio (NHtR) are two indicators of upper body obesity that are affordable, easy to obtain, highly reproducible, and more practical in the crowded health centers than the classic anthropometric indices.

Methods

18-65-year-old individuals with no past medical history were included. After obtaining written informed consent, they were screened for hypertension, high blood glucose, and other abnormal laboratory results. Data were analyzed using SPSS and Mann-Whitney U test, Chi square test, Spearman's correlation coefficient, and ROC curve.

Results

In our 2,812 participants, NC had the lowest area under the curve (AUC) in both male and female obese and overweight subjects. NHtR and hip circumference (HC) had the highest AUC in men and women with obesity, respectively. The highest sensitivity for overweight men and women belonged to waist circumference (WC) and waist-to-height ratio (WHtR), respectively, and for both males and females with obesity, NHtR had the highest sensitivity. The cutoff point of NHtR had the same value for males and females. HC and NHtR had the highest positive likelihood ratio (PLR) for obesity in men. In addition, HC and WC had the highest PLR for obesity in women.

Conclusion

In this study, we revealed that NC had the lowest and NHtR and HC had the highest predictive value for obesity. Furthermore, for both males and females with obesity, NHtR had the highest sensitivity. HC had the highest PLR for obesity in both genders. Our results warrant prospective studies to evaluate the role of NHtR and other novel anthropometric indices in the risk of cardiometabolic diseases.

Association Between Sleep Time and Pro- and Anti-Inflammatory Biomarkers Is Mediated by Abdominal Obesity Among Adolescents

OBJECTIVES

Movement behaviors and abdominal obesity are associated with higher inflammatory biomarkers. However, the role of waist circumference as a mediating factor is still unknown. Thus, our aims were to (1) test the associations between 24-hour movement behavior variables (physical activity, sedentary behavior, and sleep), abdominal obesity, and pro- and anti-inflammatory biomarkers; and (2) investigate whether abdominal obesity had a mediating effect between the investigated associations.

METHODS

This multicenter cross-sectional study included 3591 adolescents (aged 12-17 y) from 4 Brazilian cities. Waist circumference (in centimeters; at half the distance between the iliac crest and at the lower costal margin), 24-hour movement behaviors (validated questionnaire), high-sensitive C-reactive protein, and adiponectin (serum plasma) were evaluated. We used multiple mediation regression models (95% confidence interval) to determine if waist circumference mediated the association between 24-hour movement behaviors and pro- and anti-inflammatory biomarkers.

RESULTS

The results revealed that screen time and moderate to vigorous physical activity were not associated with pro- or anti-inflammatory biomarkers. However, sleep duration (in hours per day) was negatively associated with pro- (C-reactive protein, β = -0.08; 95% confidence interval, -0.38 to -0.02) and anti- (adiponectin, β = -0.31; 95% confidence interval, -2.13 to -0.12) inflammatory biomarkers. Our results also showed that waist circumference mediated the association between sleep duration and high-sensitive C-reactive protein (2.7%), and adiponectin (2.8%).

CONCLUSION

Sleep duration was inversely associated with pro- and anti-inflammatory biomarkers, and these relations were mediated by abdominal obesity. Therefore, adolescents having healthy sleep can have implications for reducing waist circumference and inflammatory indicators.

Post-malnutrition growth and its associations with child survival and non-communicable disease risk: a secondary analysis of the Malawi 'ChroSAM' cohort

OBJECTIVE

To explore patterns of post-malnutrition growth (PMGr) during and after treatment for severe malnutrition and describe associations with survival and non-communicable disease (NCD) risk 7 years post-treatment.

DESIGN

Six indicators of PMGr were derived based on a variety of timepoints, weight, weight-for-age z-score and height-for-age z-score (HAZ). Three categorisation methods included no categorisation, quintiles and latent class analysis (LCA). Associations with mortality risk and seven NCD indicators were analysed.

SETTING

Secondary data from Blantyre, Malawi between 2006 and 2014.

PARTICIPANTS

A cohort of 1024 children treated for severe malnutrition (weight-for-length z-score < 70 % median and/or MUAC (mid-upper arm circumference) < 110 mm and/or bilateral oedema) at ages 5-168 months.

RESULTS

Faster weight gain during treatment (g/d) and after treatment (g/kg/day) was associated with lower risk of death (adjusted OR 0·99, 95 % CI 0·99, 1·00; and adjusted OR 0·91, 95 % CI 0·87, 0·94, respectively). In survivors (mean age 9 years), it was associated with greater hand grip strength (0·02, 95 % CI 0·00, 0·03) and larger HAZ (6·62, 95 % CI 1·31, 11·9), both indicators of better health. However, faster weight gain was also associated with increased waist:hip ratio (0·02, 95 % CI 0·01, 0·03), an indicator of later-life NCD risk. The clearest patterns of association were seen when defining PMGr based on weight gain in g/d during treatment and using the LCA method to describe growth patterns. Weight deficit at admission was a major confounder.

CONCLUSIONS

A complex pattern of benefits and risks is associated with faster PMGr. Both initial weight deficit and rate of weight gain have important implications for future health.

Body Composition and Phase Angle: How to Improve Nutritional Evaluation in Juvenile Dermatomyositis Patients

(1) Background: This study aimed to assess body composition (BC) using bioelectrical impedance and food intake in juvenile dermatomyositis (JDM) patients. Associations between BC and physical activity, disease activity/cumulative damage and health-related quality of life parameters were also evaluated; (2) Methods: This was a cross-sectional study with 30 consecutive JDM patients (18 female and 12 male) and 24 healthy volunteers (14 female and 10 male) of both sexes followed at our pediatric rheumatology unit. The gathering of anthropometric and dietary data, and the performance of physical activity and bioelectrical impedance were undertaken in face-to-face meetings and through questionnaires. Clinical and therapeutic data were collected from medical records according to information from routine medical appointments; (3) Results: The frequency of high/very high body fat was significantly higher in controls compared with JDM patients (66.7% vs. 91.7%; p = 0.046). The median phase angle was significantly lower in patients compared with controls (5.2 ± 1.3 vs. 6.1 ± 1.0; p = 0.016). Body fat and lean mass were positively correlated with disease duration (rs = +0.629, p < 0.001 and rs = +0.716, p < 0.001, respectively) and phase angle (PhA) (rs = +0.400, p = 0.029 and rs = +0.619, p < 0.001, respectively). JDM patients with PhA ≥ 5.5 presented higher lean mass when compared with patients with PhA < 5.5 (p = 0.001); (4) Conclusions: Bioelectrical impedance can be a useful auxiliary exam in the medical and nutritional follow-up of JDM patients, because it seems to impact functional ability. These findings may assist professionals when advising JDM patients about the importance of physical activity and healthy eating in the preservation of lean mass.

Birthweight, postnatal growth and blood pressure in adolescents of low socioeconomic condition: a cohort study in Northeast Brazil

OBJECTIVE

To verify the influence of low birth weight and rapid postnatal weight gain and associated factors on blood pressure in adolescence in a population of low socioeconomic status, considering that injuries occur in the perinatal period can be predictors of future metabolic changes and are still poorly explored.

METHODS

A cohort study was carried out with 208 adolescents, 78 born with low weight and 130 born with appropriate weight. The infants were followed up during the first six postnatal months and reassessed at 8 and 18 years of age. The independent variables were birthweight and postnatal weight gain. Rapid postnatal weight gain was defined when above 0.67 z score. The co-variables were sex, maternal height and family income at birth, nutritional status at eight years old, socioeconomic conditions, nutritional status, fat mass index, and physical activity level at 18 years. The outcome variable was blood pressure at 18 years old. The bivariate and multivariable logistic regression analysis were realized and p < 0,05 was considered significant.

RESULTS

The proportion of adolescents with elevated blood pressure was 37.5%. The multivariable logistic regression analysis showed the variables independently associated with a higher chance of elevated blood pressure in adolescence were rapid postnatal weight gain (OR = 2.74; 95% CI 1.22-6.14; p = 0.014), male sex (OR = 4.15; 95% CI 1.66-10.38; p = 0.002) and being physically active (OR = 2.70; 95% CI 1.08-6.74; p = 0.034).

CONCLUSIONS

The rapid postnatal weight gain was a predictor for elevated blood pressure in adolescence, independently of other factors.

Prevalence and Predictors of Prediabetes in Adolescents and Young Adults with Turner Syndrome: A Cross-Sectional Study from Eastern India

Background

Individuals with Turner syndrome (TS) have a high risk for prediabetes/type 2 Diabetes Mellitus (T2DM). There is scarce data regarding risk factors for prediabetes in TS, specially from South Asia.

Methods

We conducted a cross-sectional study on girls with TS aged 12-30 years who had achieved pubertal stage B3 and above-spontaneously or with oestrogen. Anthropometric measurements and biochemical tests were conducted, and medical records were reviewed for details about pubertal onset and progression, growth hormone (GH) and oestrogen therapy.

Results

Out of 129 patients with TS in our database, 99 met the criteria for inclusion, mean age 18.33+/-3.78 years and mean BMI 20.57+/- 3.71 kg/m2. Prevalence of prediabetes was 23.23%. Plasma-glucose measured after 75 g-oral-anhydrous-glucose-load (OGTT-PPG) identified five additional prediabetes cases, who had normal fasting plasma glucose (FPG) or HbA1c%. Compared to those without prediabetes, TS with prediabetes (n = 23) had higher mean body weight, BMI, waist circumference (WC) [42.02+/- 5.83 vs 36.22+/-8.07, 22.77+/-2.78 vs 19.91+/- 3.72, 85.26+/- 3.52 vs 81.08+/- 4.59, pall < 0.03 ], higher median WC-to-height ratio (WHtR) and WC-to-hip ratio (WHR)((0.64 [0.6-0.69] vs 0.59[0.56- 0.66], 0.9[0.84-1.12] vs 0.85[0.75-1.01], pboth < 0.02), and higher LDL-cholesterol, triglycerides, and greater prevalence of hepatosteatosis (47.1% vs 21.1%, P < 0.01). Among GH recipients (n = 36), those with prediabetes had delayed initiation and shorter duration of GH therapy. There were no differences in cardiometabolic parameters or the prevalence of diabetes between different karyotypic variants of TS. BMI, WC and WHR had significant positive correlation with FBG, OGTT-PPG and HbA1c% (pall < 0.004). Delay in oestrogen initiation had a significant correlation with OGTT-PPG (Spearman's-rho = 0.69, P < 0.004). BMI, WHR and pubertal status were independent predictors for prediabetes (OR: 1.27 [1.03-1.57]), 1.18 [1.04-1.34]) and 0.09[0.02-0.38], respectively, pall < 0.02), but karyotype was not. BMI had the highest sensitivity [cut-off: 21.04 kg/m2 (sensitivity: 82.6%, specificity: 62.2%) and WHR had the highest specificity [cut-off: 0.89 (sensitivity: 73.9%, specificity 78.4%)] for predicting prediabetes.

Conclusion

Indian girls with TS have a high risk for prediabetes, irrespective of underlying karyotype and should be screened with oral glucose challenge to identify prediabetes. Timely intervention against central obesity and early initiation of GH and oestrogen should be ensured in TS. Late presenting girls should be closely monitored for dysglycaemia before and during treatment with GH and/or oestrogen.

The stability of cardiometabolic risk factors clustering in children and adolescents: a 2-year longitudinal study

Objective

The present study aims to verify the odds of remaining with the clustering of 3 or more, 4 or more, and 5 or more risk factors across a 2-year time span.

Methods

Observational longitudinal study that included 358 children and adolescents (10.96 ± 2.28 years of age at baseline). Cardiorespiratory fitness, glucose, systolic blood pressure, total cholesterol/high-density lipoprotein cholesterol ratio, triglycerides, and waist circumference were assessed. The number of children in whom the risk factors were not independently distributed was analyzed. Odds ratios of presenting n risk factors clustered at follow-up according to the number of risk factors observed at baseline were calculated.

Results

More participants than expected were found presenting clustering of 4 or more and 5 or more risk factors at both baseline (11.7% and 5.6%, respectively) and follow-up (9.5% and 5.6%, respectively). The odds ratios calculated demonstrated that the odds of presenting the same number of risk factors clustered or more at follow-up increased according to the number of risk factors clustered at baseline.

Conclusion

The higher the number of risk factors a child had at baseline, the higher the odds of presenting the same number of risk factors or more after two years of follow-up.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40200-022-01174-1.

Associations Between Socioeconomic Status, Obesity, Cognition, and White Matter Microstructure in Children

Importance

Lower neighborhood and household socioeconomic status (SES) are associated with negative health outcomes and altered brain structure in children. It is unclear whether such findings extend to white matter and via what mechanisms.

Objective

To assess whether and how neighborhood and household SES are independently associated with children's white matter microstructure and examine whether obesity and cognitive performance (reflecting environmental cognitive and sensory stimulation) are plausible mediators.

Design, Setting, and Participants

This cross-sectional study used baseline data from participants in the Adolescent Brain Cognitive Development (ABCD) study. Data were collected at 21 US sites, and school-based recruitment was used to represent the US population. Children aged 9 to 11 years and their parents or caregivers completed assessments between October 1, 2016, and October 31, 2018. After exclusions, 8842 of 11 875 children in the ABCD study were included in the analyses. Data analysis was conducted from July 11 to December 19, 2022.

Exposures

Neighborhood disadvantage was derived from area deprivation indices at participants' primary residence. Household SES factors were total income and highest parental educational attainment.

Main Outcomes and Measures

A restriction spectrum imaging (RSI) model was used to quantify restricted normalized directional (RND; reflecting oriented myelin organization) and restricted normalized isotropic (RNI; reflecting glial and neuronal cell bodies) diffusion in 31 major white matter tracts. The RSI measurements were scanner harmonized. Obesity was assessed through body mass index (BMI; calculated as weight in kilograms divided by height in meters squared), age- and sex-adjusted BMI z scores, and waist circumference, and cognition was assessed through the National Institutes of Health Toolbox Cognition Battery. Analyses were adjusted for age, sex, pubertal development stage, intracranial volume, mean head motion, and twin or siblingship.

Results

Among 8842 children, 4543 (51.4%) were boys, and the mean (SD) age was 9.9 (0.7) years. Linear mixed-effects models revealed that greater neighborhood disadvantage was associated with lower RSI-RND in the left superior longitudinal fasciculus (β = -0.055; 95% CI, -0.081 to -0.028) and forceps major (β = -0.040; 95% CI, -0.067 to -0.013). Lower parental educational attainment was associated with lower RSI-RND in the bilateral superior longitudinal fasciculus (eg, right hemisphere: β = 0.053; 95% CI, 0.025-0.080) and bilateral corticospinal or pyramidal tract (eg, right hemisphere: β = 0.042; 95% CI, 0.015-0.069). Structural equation models revealed that lower cognitive performance (eg, lower total cognition score and higher neighborhood disadvantage: β = -0.012; 95% CI, -0.016 to -0.009) and greater obesity (eg, higher BMI and higher neighborhood disadvantage: β = -0.004; 95% CI, -0.006 to -0.001) partially accounted for the associations between SES and RSI-RND. Lower household income was associated with higher RSI-RNI in most tracts (eg, right inferior longitudinal fasciculus: β = -0.042 [95% CI, -0.073 to -0.012]; right anterior thalamic radiations: β = -0.045 [95% CI, -0.075 to -0.014]), and greater neighborhood disadvantage had similar associations in primarily frontolimbic tracts (eg, right fornix: β = 0.046 [95% CI, 0.019-0.074]; right anterior thalamic radiations: β = 0.045 [95% CI, 0.018-0.072]). Lower parental educational attainment was associated with higher RSI-RNI in the forceps major (β = -0.048; 95% CI, -0.077 to -0.020). Greater obesity partially accounted for these SES associations with RSI-RNI (eg, higher BMI and higher neighborhood disadvantage: β = 0.015; 95% CI, 0.011-0.020). Findings were robust in sensitivity analyses and were corroborated using diffusion tensor imaging.

Conclusions and Relevance

In this cross-sectional study, both neighborhood and household contexts were associated with white matter development in children, and findings suggested that obesity and cognitive performance were possible mediators in these associations. Future research on children's brain health may benefit from considering these factors from multiple socioeconomic perspectives.

Unrecognized hypertension among a general adult Ghanaian population: An urban community-based cross-sectional study of prevalence and putative risk factors of lifestyle and obesity indices

Hypertension (HTN) is the leading cause of cardiovascular diseases. Nevertheless, most individuals in developing countries are unaware of their blood pressure status. We determined the prevalence of unrecognized hypertension and its association with lifestyle factors and new obesity indices among the adult population. This community-based study was conducted among 1288 apparently healthy adults aged 18-80 years in the Ablekuma North Municipality, Ghana. Sociodemographic, lifestyle characteristics, blood pressure and anthropometric indices were obtained. The prevalence of unrecognized HTN was 18.4% (237 / 1288). The age groups 45-54 years [aOR = 2.29, 95% CI (1.33-3.95), p = 0.003] and 55-79 years [aOR = 3.25, 95% CI (1.61-6.54), p = 0.001], being divorced [aOR = 3.02 95% CI (1.33-6.90), p = 0.008], weekly [aOR = 4.10, 95% CI (1.77-9.51), p = 0.001] and daily alcohol intake [aOR = 5.62, 95% CI (1.26-12.236), p = 0.028] and no exercise or at most once a week [aOR = 2.25, 95% CI (1.56-3.66), p = 0.001] were independently associated with HTN. Among males, the fourth quartile (Q4) of both body roundness index (BRI) and waist to height ratio (WHtR) [aOR = 5.19, 95% CI (1.05-25.50), p = 0.043] were independent determinants of unrecognized HTN. Among females, the third quartile (Q3) [aOR = 7.96, 95% CI (1.51-42.52), p = 0.015] and Q4 [aOR = 9.87 95% CI (1.92-53.31), p = 0.007] of abdominal volume index (AVI), the Q3 of both BRI and WHtR [aOR = 6.07, 95% CI (1.05-34.94), p = 0.044] and Q4 of both BRI and WHtR [aOR = 9.76, 95% CI (1.74-54.96), p = 0.010] were independent risk factors of HTN. Overall, BRI (AUC = 0.724) and WHtR (AUC = 0.724) for males and AVI (AUC = 0.728), WHtR (AUC = 0.703) and BRI (AUC = 0.703) for females yielded a better discriminatory power for predicting unrecognized HTN. Unrecognized hypertension is common among the apparently healthy adults. Increased awareness of its risk factors, screening, and promoting lifestyle modification is needed to prevent the onset of hypertension.

Childhood obesity is linked to putative neuroinflammation in brain white matter, hypothalamus, and striatum

Neuroinflammation is both a consequence and driver of overfeeding and weight gain in rodent obesity models. Advances in magnetic resonance imaging (MRI) enable investigations of brain microstructure that suggests neuroinflammation in human obesity. To assess the convergent validity across MRI techniques and extend previous findings, we used diffusion basis spectrum imaging (DBSI) to characterize obesity-associated alterations in brain microstructure in 601 children (age 9-11 years) from the Adolescent Brain Cognitive DevelopmentSM Study. Compared with children with normal-weight, greater DBSI restricted fraction (RF), reflecting neuroinflammation-related cellularity, was seen in widespread white matter in children with overweight and obesity. Greater DBSI-RF in hypothalamus, caudate nucleus, putamen, and, in particular, nucleus accumbens, correlated with higher baseline body mass index and related anthropometrics. Comparable findings were seen in the striatum with a previously reported restriction spectrum imaging (RSI) model. Gain in waist circumference over 1 and 2 years related, at nominal significance, to greater baseline RSI-assessed restricted diffusion in nucleus accumbens and caudate nucleus, and DBSI-RF in hypothalamus, respectively. Here we demonstrate that childhood obesity is associated with microstructural alterations in white matter, hypothalamus, and striatum. Our results also support the reproducibility, across MRI methods, of findings of obesity-related putative neuroinflammation in children.

Independent and Joined Association between Socioeconomic Indicators and Pediatric Obesity in Spain: The PASOS Study

Childhood obesity is a public health problem worldwide. An important determinant of child and adolescent obesity is socioeconomic status (SES). However, the magnitude of the impact of different SES indicators on pediatric obesity on the Spanish population scale is unclear. The aim of this study was to assess the association between three SES indicators and obesity in a nationwide, representative sample of Spanish children and adolescents. A total of 2791 boys and girls aged 8 to 16 years old were included. Their weight, height, and waist circumference were measured. SES was assessed using two parent/legal guardian self-reported indicators (educational level -University/non-University- and labor market status -Employed/Unemployed-). As a third SES indicator, the annual mean income per person was obtained from the census section where the participating schools were located (≥12.731€/<12.731€). The prevalence of obesity, severe obesity, and abdominal obesity was 11.5%, 1.4%, and 22.3%, respectively. Logistic regression models showed an inverse association of both education and labor market status with obesity, severe obesity, and abdominal obesity (all p < 0.001). Income was also inversely associated with obesity (p < 0.01) and abdominal obesity (p < 0.001). Finally, the highest composite SES category (University/Employed/≥12.731€ n = 517) showed a robust and inverse association with obesity (OR = 0.28; 95% CI: 0.16-0.48), severe obesity (OR = 0.20; 95% CI: 0.05-0.81), and abdominal obesity (OR = 0.36; 95% CI: 0.23-0.54) in comparison with the lowest composite SES category (Less than University/Unemployed/<12.731€; n = 164). No significant interaction between composite SES categories and age and gender was found. SES is strongly associated with pediatric obesity in Spain.

The association between food insecurity status and COVID-19 in an Iranian population: a case-control study

Aim

The 2019 novel coronavirus epidemic (COVID-19) is a highly contagious viral disease with a high rate of morbidity and mortality. Food insecurity has frequently been linked to the emergence of infectious diseases. The present study was conducted to determine the association of food insecurity and socioeconomic status with COVID-19 in the Iranian population.

Subject and methods

The study was a case-control study including 248 participants (124 COVID-19-infected people with a positive PCR test and a history of clinical symptoms of COVID-19 and 124 non-infected people with a negative PCR test and no history of clinical symptoms of COVID-19 infection) aged 20 to 60 years. The participants in the two groups were matched based on age, sex, and BMI. Anthropometric and socioeconomic data were collected. Individuals' food insecurity status during the previous 12 months (before the disease for the case group) was assessed using a validated 18-item USDA questionnaire.

Results

About 44% of the controls and 76% of the case group were food-insecure (P < 0.001). After controlling for any possible confounders, only food insecurity and poor economic level increased the risk of COVID-19, by about three times (OR = 3.10; 95% CI = 1.44-6.68; P = 0.004) and 9.5 times (OR = 9.53; 95% CI = 3.73-24.30; P < 0.001), respectively.

Conclusion

Food insecurity and poor economic status are linked to an increased risk of COVID-19. Future prospective studies are needed to confirm these outcomes and identify the underlying mechanisms.

Associations between socioeconomic status and white matter microstructure in children: indirect effects via obesity and cognition

Importance

Both neighborhood and household socioeconomic disadvantage relate to negative health outcomes and altered brain structure in children. It is unclear whether such findings extend to white matter development, and via what mechanisms socioeconomic status (SES) influences the brain.

Objective

To test independent associations between neighborhood and household SES indicators and white matter microstructure in children, and examine whether body mass index and cognitive function (a proxy of environmental cognitive/sensory stimulation) may plausibly mediate these associations.

Design

This cross-sectional study used baseline data from the Adolescent Brain Cognitive Development (ABCD) Study, an ongoing 10-year cohort study tracking child health.

Setting

School-based recruitment at 21 U.S. sites.

Participants

Children aged 9 to 11 years and their parents/caregivers completed baseline assessments between October 1 st , 2016 and October 31 st , 2018. Data analysis was conducted from July to December 2022.

Exposures

Neighborhood disadvantage was derived from area deprivation indices at primary residence. Household SES indicators were total income and the highest parental education attainment.

Main Outcomes and Measures

Thirty-one major white matter tracts were segmented from diffusion-weighted images. The Restriction Spectrum Imaging (RSI) model was implemented to measure restricted normalized directional (RND; reflecting oriented myelin organization) and isotropic (RNI; reflecting glial/neuronal cell bodies) diffusion in each tract. Obesity-related measures were body mass index (BMI), BMI z -scores, and waist circumference, and cognitive performance was assessed using the NIH Toolbox Cognition Battery. Linear mixed-effects models tested the associations between SES indicators and scanner-harmonized RSI metrics. Structural equation models examined indirect effects of obesity and cognitive performance in the significant associations between SES and white mater microstructure summary principal components. Analyses were adjusted for age, sex, pubertal development stage, intracranial volume, and head motion.

Results

The analytical sample included 8842 children (4299 [48.6%] girls; mean age [SD], 9.9 [0.7] years). Greater neighborhood disadvantage and lower parental education were independently associated with lower RSI-RND in forceps major and corticospinal/pyramidal tracts, and had overlapping associations in the superior longitudinal fasciculus. Lower cognition scores and greater obesity-related measures partially accounted for these SES associations with RSI-RND. Lower household income was related to higher RSI-RNI in almost every tract, and greater neighborhood disadvantage had similar effects in primarily frontolimbic tracts. Lower parental education was uniquely linked to higher RSI-RNI in forceps major. Greater obesity-related measures partially accounted for these SES associations with RSI-RNI. Findings were robust in sensitivity analyses and mostly corroborated using traditional diffusion tensor imaging (DTI).

Conclusions and Relevance

These cross-sectional results demonstrate that both neighborhood and household contexts are relevant to white matter development in children, and suggest cognitive performance and obesity as possible pathways of influence. Interventions targeting obesity reduction and improving cognition from multiple socioeconomic angles may ameliorate brain health in low-SES children.

Key Points

Question: Are neighborhood and household socioeconomic levels associated with children’s brain white matter microstructure, and if so, do obesity and cognitive performance (reflecting environmental stimulation) mediate the associations?Findings: In a cohort of 8842 children, higher neighborhood disadvantage, lower household income, and lower parental education had independent and overlapping associations with lower restricted directional diffusion and greater restricted isotropic diffusion in white matter. Greater body mass index and poorer cognitive performance partially mediated these associations.Meaning: Both neighborhood and household poverty may contribute to altered white matter development in children. These effects may be partially explained by obesity incidence and poorer cognitive performance.

Association between Meal Frequency and Weight Status in Spanish Children: A Prospective Cohort Study

Childhood obesity is a major international problem, and unhealthy eating habits remain widespread. Increasing the frequency of meals of nutritious food can help children to regulate their appetite and maintain a healthy weight. However, there is scarce prospective evidence on the relationship between the meal frequency and weight outcomes. Therefore, the objective of the present study was to determine the prospective association between the meal frequency, body mass index, and waist circumference in Spanish children. Additionally, we analyzed the impact of the meal frequency on the incidence of excessive weight and abdominal obesity. The study included 1400 children with a mean (SD) age of 10.1 (0.6) and an average follow-up of 15 months. Anthropometric measurements, including the body weight, height, and waist circumference, were measured by trained personnel, and children were asked about whether they usually had the following meals: breakfast, a mid-morning snack, lunch, an afternoon snack, and dinner. Multiple linear regression models revealed a significant (p < 0.05) inverse association between the meal frequency with a standardized BMI (zBMI) and the waist-to-height ratio (WHtR) after adjusting for sex, age, allocation to an intervention group, school, maternal education, physical activity, diet quality, and for the corresponding outcome variable at the baseline. Furthermore, the odds of developing abdominal obesity or excessive weight during the follow-up significantly decreased with an increase in the meal frequency after controlling for the same confounders. In conclusion, a higher meal frequency at the baseline was predictive for a lower zBMI, WHtR, and odds of the incidence of excessive weight and abdominal obesity.

Association between dietary inflammatory index and anthropometric indicators of adiposity in Brazilian adolescents

BACKGROUND

Diet may play a role in the regulation of obesity-related low-grade chronic inflammation.

OBJECTIVE

Assess the association of the Dietary Inflammatory Index (DII) with anthropometric indicators of adiposity in Brazilian adolescents.

METHODS

Data were collected from 71 740 adolescents (12-17 years old) examined in the Study of Cardiovascular Risks in Adolescents. Food consumption was assessed by means of one 24-h dietary recall, and DII was estimated using 39 food parameters. The body mass index (weight/height² ) for age and sex was used to define overweight (>1 z-score). Abdominal obesity was indicated by waist circumference (WC) values >80th percentile and waist-to-height ratio (WHtR) > 0.50. The association between DII and anthropometric indicators was assessed using logistic regression models.

RESULTS

The mean DII score was higher in girls than in boys (0.77; SD = 0.04 vs. 0.04; SD = 0.05). Adolescents in the 4th quartile of DII, compared with those in the 1st quartile, had increased odds of being overweight (boys: OR = 1.76; 95% CI: 1.37; 2.25; girls: OR = 1.63; 95%CI: 1.36; 1.95), having abdominal obesity (boys: OR = 1.61; 95%CI: 1.33; 1.95; girls: OR = 1.73; 95%CI: 1.48; 2.03), and having high WHtR (boys: OR = 1.91; 95%CI: 1.52; 2.39; girls: OR = 1.75; 95%CI: 1.46; 2.11).

CONCLUSIONS

The findings showed a direct association between the dietary inflammatory potential measured by DII and adiposity.

An Investigation of the Utility of Waist Circumference Predicting Cardiorespiratory Fitness in School Children: A Cross-Sectional Study

The early identification of modifiable risk factors and their monitoring, also within school physical education (PE) classes, are becoming indispensable in the context of public health. The aim of this study was to test whether making use of waist circumference (WC) measurements increases the possibility of predicting the results of cardiorespiratory fitness (CRF) in school-age children, as compared with body mass index (BMI) and other somatic indicators related to body fat. The cross-sectional study covered 190 children aged 10 to 15 years, participating in school PE classes. Body height (BH), body weight (BW), WC, hip circumference (HC) and percentage of body fat (BF%) were measured. BMI, waist to hip ratio (WHR) and waist to height ratio (WHtR) were calculated, and a CRF test was performed by means of a 20 m shuttle run test (20mSRT). The peak heart rate (HR_peak) of the children was also measured. The regression model that was developed showed that WC (R² = 47.1%), beyond BF% (R² = 50.3%) and WHtR (R² = 50.0%), was a useful measure of CRF, and stronger than BMI (R² = 45.8%) or WHR (R² = 39.2%). The risk of obtaining the CRF result classified below a good level (below the percentile range of P60-P80) was significantly higher in children with a larger WC (odds ratio (OR) for the WC change of 1 cm equals 1.14 (95% CI: 1.09-1.20; p < 0.001)). The simplicity of measuring WC and the possibility of using this measurement in the calculation of WHtR with reference to CRF indicate its usefulness in the prophylactic exams of school children.

Association between abdominal obesity, screen time and sleep in adolescents

OBJECTIVE

To assess the association between abdominal obesity, food intake, sleep deprivation, and screen time in adolescents.

METHODS

This cross-sectional study was conducted with 432 adolescents aged 14-19 years, from public and private schools. Anthropometric and body composition measures included body weight, waist circumference, body mass index for age, waist-to-hip ratio, waist-to-height ratio, and body fat percentage. Abdominal obesity was defined by age and sex specific cut-off points for waist circumference. Food intake, screen time, sexual maturation, and sleep duration were evaluated by self-administered questionnaires.

RESULTS

The prevalence of excess body weight and abdominal obesity was 16.7% and 27.5%, respectively. Students in the adult phase (post-puberty), with inadequate waist-to-height ratio, high body fat percentage, and screen time ≥ 3 h/day were, respectively, 2.5 (95% CI 1.40-4.46), 7.44 (95% CI 1.08-51.46), 2.79 (95% CI 1.04-7.50), and 1.43 (95% CI 1.24-3.89) more likely to have abdominal obesity. Low intake of unprocessed or minimally processed foods was associated with inadequate sleep duration, while high intake of ultra-processed foods was associated with high screen time.

CONCLUSIONS

Abdominal obesity was associated with the adult phase, short sleep duration and high screen time. The degree of food processing was associated with screen time and sleep duration. Assessing the risk factors of abdominal obesity may be a useful strategy for preventing cardiovascular disease in adolescents.

Psychological Aspects, Physical Activity Levels and Overweight Concerns: A Cross-over Study of Brazilian Adolescents

Introduction

This study aims to identify levels of anxiety, depression, body weight, and levels of physical activity, as well as to verify possible associations among these variables in Brazilian adolescents. It is a cross-sectional study with a convenience sample of 291 Brazilian adolescents aged 13 to 15 years old (13.75±0.80 years old).

Methods

Researchers assessed students by filling out questionnaires of anxiety and depression symptoms, as well as the level of physical activity and checking anthropometric measures. Parametric and non-parametric statistics were used to compare groups divided by psychological, physical and overweight factors for boys and girls, adopting a significance level of 95%.

Results

Results showed higher waist circumference and physical activity levels for boys (p<0.01) and higher scores for anxiety and depressive symptoms questionnaires for girls (p<0.01). In addition, a low prevalence of depression was observed in boys (0.69%/CI0.03-4.36). For anxiety and depression variables in males and females with and without overweight and physically active and inactive, there were significant differences between groups (p < 0.05), but not within groups.

Conclusion

The identification of a higher prevalence of girls with anxiety and depression was observed in this study and reinforced this information already demonstrated in the scientific literature. In general, the prevalence of depression was low in boys, while the prevalence of overweight, sedentary lifestyle, anxiety and depression were higher in girls.

Anthropometric Indicators to Estimate Percentage of Body Fat: A Comparison Using Cross-Sectional Data of Children and Adolescents in Ho Chi Minh City, Vietnam

OBJECTIVES

To compare the association between waist circumference (WC), waist-to-hip ratio (WHR), waist-to-height ratio (WHtR), body mass index (BMI), and percentage of body fat (PBF) measured by dual energy X-ray absorptiometry (DXA) method in children and adolescents of Vietnam.

METHODS

This cross-sectional study included 153 children and adolescents aged 6-18 y old in Ho Chi Minh City, Vietnam. Correlations between indicators were determined using Pearson correlation coefficient (r). Linear regression was carried out with PBF as dependent variable to test the further association of potential indicators.

RESULTS

The strongest correlation was found between PBF and WHtR in all pubertal stages (0.712; 0.556; 0.638 in male; 0.635; 0.799; 0.611 in female, respectively). The regression analysis indicated that WHtR was the most effective estimator of PBF ([Formula: see text] = 0.69, RMSE = 4.54 for male; [Formula: see text] = 0.50, RMSE = 4.34 for female) in the model including pubertal stage variable for each gender.

CONCLUSIONS

The results support the use of WHtR as an effective indicator for detecting adiposity in Vietnamese children and adolescents.

Association between diet quality index, food and nutrient intake and metabolic parameters in adolescents from Recife, northeastern Brazil

Nutritional studies shifted the focus of attention to the analysis of food quality, addressing general diet considering the foods, food groups and nutrients included. This study evaluates the association between diet quality index, food and nutrient intake and metabolic parameters of adolescents from Recife, northeastern Brazil. It is a cross-sectional study involving adolescents aged 12 to 19 years. Food intake was assessed using the FFQ to estimate the adapted Diet Quality Index for Adolescents for Brazilians (DQIA-BR-A). The analysis included metabolic parameters (glucose, lipid profile, apo A1 and B, α-1-acid glycoprotein, retinol, β-carotene, α-tocopherol, 25-hydroxyvitamin D and parathormone). Multiple linear regression analysis between the DQIA-BR-A and daily nutrient intake showed a positive correlation (R²_adjusted = 0·29) for linoleic fatty acid, Ca and folate and a negative correlation for oleic fatty acid, carbohydrates and vitamins B₂ and C, in addition to a low correlation (R²_adjusted < 0·07) with all metabolic parameters. However, the DQIA-BR-A correlated significantly (R²_adjusted = 0·62; P < 0·001) with food intake. In this way, the DQIA-BR-A can be considered as an accurate and useful instrument for assessing the overall quality of adolescent diets. The diet of the adolescents was considered to be of moderate quality. Changes are required to ensure a balanced diet, considering the high-sugar intake and consumption of sweets as well as the low consumption of vegetables, milk and dairy products, oils, fats and seeds. Such changes should prioritise the consumption of foods rich in essential fatty acids and poor in saturated fat.

[Temporal variation in the incidence of overweight and abdominal obesity among adolescents in the city of Salvador, Bahia, Brazil]

The scope of this study was to analyze the temporal variation in the incidence of overweight and abdominal obesity among adolescents from public schools in a capital in northeastern Brazil. It is a study including information from three cross-sectional surveys carried out in 2001, 2009 and 2017, with 2,496 students aged 10 to 18 years of both sexes living in the city of Salvador, Bahia. Overweight was assessed using the Body Mass Index for Age (BMI/A) and abdominal obesity was assessed using waist circumference and waist-to-height ratio. Pooled OLS (Ordinary Least Squares) regression, with constant effect, was used to assess the variation of anthropometric indicators over the period. The results of this study indicate that the prevalence of overweight increased by 103% and the indicators of abdominal obesity increased by 153% and 142%, respectively, in the period under analysis. The increase in the mean body mass index and waist-to-height ratio was greater among adolescents and in the mean BMI and waist circumference among those aged 14 to 18 years old. The conclusion reached was that there was a significant increase in the prevalence of overweight and abdominal obesity in the period 2001 to 2017 among adolescents in the city of Salvador.

Healthy lifestyles and physical fitness are associated with abdominal obesity among Latin-American and Spanish preschool children: A cross-cultural study

BACKGROUND

Identifying environmental factors that influence health in children are necessary to develop preventive strategies.

OBJECTIVE

To determine the association between the lifestyles of children (i.e., Mediterranean diet (MD), physical activity (PA), fitness and screen time (ST) with abdominal obesity (AO) of preschoolers from three Spanish-speaking countries (Chile, Colombia and Spain) with different socioeconomic levels and Human Development Index (HDI) indicators.

MATERIAL AND METHODS

This cross-sectional study included 982 schoolchildren (aged 4-6 years; 56.8% girls) from Chile (n = 409), Colombia (n = 281), and Spain (n = 292). Body mass index (BMI), waist circumference (WC), waist-to-height ratio (WtHR), adherence to the MD, PA, ST and physical fitness were evaluated.

RESULTS

Spanish preschoolers reported a lower WtHR (p < 0.001), greater physical fitness (Z-score) (p < 0.001) and higher adherence to the MD (p < 0.001) than their Chilean and Colombian peers. In addition, Colombian preschoolers had a better lifestyle (PA + ST) than their Chilean and Spanish peers (p < 0.001). Chilean preschoolers reported a higher prevalence of AO than the Spanish preschoolers (65% vs. 51.9%; p = 0.001).

CONCLUSION

Lifestyle had a significant association with AO among Spanish-speaking preschool children, with physical fitness especially being a relevant factor regardless of the country of origin. The findings of the current study may support the development of public guidelines focusing on healthy lifestyles in children to create effective plans that contribute to the early treatment of AO in preschool children.

Degree of food processing and association with overweight and abdominal obesity in adolescents

OBJECTIVE

To evaluate the association between the degree of food processing, overweight, and abdominal obesity in adolescents.

METHODS

This is a cross-sectional study, with 576 adolescents aged 10 to 17 years, of both sexes. Food consumption was collected using the Food Frequency Questionnaire and foods classified as in natura or minimally processed, processed foods associated with culinary ingredients, and ultraprocessed foods. Sociodemographic data, body mass index, waist circumference and waist-to-height ratio were collected. The analysis was evaluated by the Mann-Whitney test and prevalence ratio with 95% confidence interval, considering p<0.05.

RESULTS

An intake above the third quartile of processed foods associated with culinary ingredients (prevalence ratio of 1.64; 95%CI: 1.12-2.42) and ultraprocessed (prevalence ratio of 1.58; 95%CI: 1.07-2.34) was associated with a higher prevalence of overweight. Consumption above the third quartile of ultraprocessed foods was associated with a higher prevalence of abdominal obesity, assessed by waist circumference (prevalence ratio of 2.48; 95%CI: 1.41-4.36), and waist-height ratio (prevalence ratio of 2.09; 95%CI: 1.11-3.92).

CONCLUSION

A higher consumption of processed foods associated with culinary ingredients was related to being overweight, and ultraprocessed foods with overweight and abdominal obesity.

Moderating Role of Physical Fitness in the Association Between TV Time and Adiposity Parameters in Adolescents

PURPOSE

To identify whether physical fitness (PF) components play a moderating role in the relationship between TV time and adiposity levels.

DESIGN

Cross-sectional study.

SETTING

Few studies have examined if different PF levels modify the association between TV time and adiposity in adolescents. Studies often focus on the isolated relationships between obesity and TV time, or obesity and PF levels.

SUBJECTS

1071 adolescents (617 girls), aged 12 to 17 years.

MEASURES

Cardiorespiratory fitness (CRF), abdominal muscular endurance, and lower limb strength were evaluated using the protocols of the Projeto Esporte Brasil fitness testing battery. TV time was obtained using a self-reported questionnaire. Body mass index (BMI) and waist circumference (WC) were also assessed. Moderation analyses were conducted through multiple linear regression models with the following associations tested in different models: PF components, TV time, and interaction (PF component x TV time) with adiposity parameters (BMI and WC).

RESULTS

A significant interaction term was found for CRF and TV time in the association with both WC (β: -.005; 95% CI: -.009; -.001; P = .012) and BMI (β: -.002; 95% CI: -.004; -.001; P = .009).

CONCLUSION

CRF moderates the relationship between TV time and adiposity measures in this cross-sectional analysis. These data support strategies looking at increasing physical activity levels to improve CRF and avoid the development of excess abdominal obesity and excess weight.

Influence of Lifestyle Habits in the Development of Obesity during Adolescence

Background: The alarming increase in childhood obesity is a global public health problem since it has significant health consequences. This cross-sectional study aimed to identify the potentially modifiable risk factors for developing excess weight and determine the importance of developing certain habits to prevent childhood overweight and obesity. Methods: The sample included 416 students between the ages of 12 and 14 (12.8 ± 0.62) first-year high school students from Murcia in Spain. Data were collected on their lifestyle habits through the ENHASA questionnaire, and the somatometry of the participants was measured. Such data were studied through structural equation modeling and importance-performance map analyses. Results: The modifiable risk factors that presented the greatest potency directly regarding when developing excess weight in adolescents were ‘use of electronic devices’ and ‘not performing physical activity’ (p < 0.001). ‘Social and school environment’ and ‘diet’ showed relationships but no significant differences with overweight or obesity. Globally, the lifestyle habit of the greatest importance for not being overweight was ‘engagement in extracurricular physical activities’. On the other hand, the habits related to using new technologies in a sedentary way showed the best capacity for improvement. Therefore, it would be very efficient to focus on them to control excess weight. Conclusion: Responsible and limited use of screens and engaging in extracurricular physical activities may be the most remarkable and cost-effective strategies for obesity prevention programs.

Defining Optimal Cut-Points for Cardiorespiratory Fitness Associated With Overweight/Obesity in Children: A School-Based Study

The main purpose of the study was to define optimal criterion-referenced cut-points for cardiorespiratory fitness (CRF) associated with overweight/obesity. In this cross-sectional study, participants were 1,612 children aged 7–14 years (mean age ± SD = 9.7 ± 2.4 years; 52.5% girls). CRF was assessed by the Maximal multistage 20-m shuttle run test, from which maximal oxygen uptake (VO₂max) was estimated. Anthropometric indices included body-mass index (BMI), waist circumference (WC), and waist-to-height ratio (WHtR). Receiver operating characteristic (ROC) curves were performed to determine cut-off points. In boys, the optimal cut-off points of CRF in defining overweight/obesity for BMI, WC, and WHtR were 44.6, 46.4, and 46.9 mlO₂/kg/min. The areas under the curves (AUC) were 0.83 (95% CI 0.78–0.88, p < 0.001), 0.77 (95% CI 0.71–0.83, p < 0.001), and 0.90 (95% CI 0.86–0.93, p < 0.001). In girls, the optimal cut-off points were 41.0, 40.8, and 40.7 mlO₂/kg/min for BMI, WC, and WHtR, with the AUCs of 0.86 (95% CI 0.82–0.90, p < 0.001), 0.83 (95% CI 0.79–0.88), and 0.88 (95% CI 0.84–0.93, p < 0.001). In conclusion, our newly developed cut-off points for CRF assessed by the Maximal multistage 20-m shuttle run test may adequately detect primary school-aged boys and girls with general and abdominal obesity.

Intake of ultra-processed foods is associated with inflammatory markers in Brazilian adolescents

OBJECTIVE

To evaluate the association of the consumption of foods of the ultra-processed group (UPF) with inflammatory markers in the adolescent population in Northeastern Brazil.

DESIGN

A cross-sectional population-based study. Food consumption was evaluated using two 24-h dietary recalls using the NOVA classification for food processing levels. The following inflammatory markers were evaluated: adiponectin, IL-6, IL-8, C-reactive protein (CRP) and TNF-α. Multivariate linear regression was used to investigate the association between the percentage of UPF energy contribution and inflammatory markers.

SETTING

São Luís, Maranhão, Brazil.

PARTICIPANTS

The sample consisted of 391 male and female adolescents, aged from 17 to 18 years.

RESULTS

The average daily energy consumption by adolescents was 8032·9 kJ/d, of which 26·1 % originated from UPF. The upper tertile (T3) of UPF consumption presented higher intake of simple carbohydrates, lipids, saturated fat, and Na and lower protein intake. Individuals in T3 presented higher serum leptin and CRP levels (P < 0·05). Adolescents with UPF energy consumption ≥30·0 % (tertile 3 of UPF) had a 79 % (exp (0·58) = 1·79) increase in IL-8 levels when compared with adolescents in tertile 1 of UPF (P = 0·013).

CONCLUSIONS

The association between the consumption of UPF, poor quality diet and pro-inflammatory markers have important harmful effects that can be observed as early as in adolescence.

Diet Quality Scores and Cardiometabolic Risk Factors in Mexican Children and Adolescents: A Longitudinal Analysis

There is limited evidence for the effects of diet on cardiometabolic profiles during the pubertal transition. We collected repeated measures of diet quality and cardiometabolic risk factors among Mexican youth. This analysis included 574 offspring of the Early Life Exposure in Mexico to Environmental Toxicants (ELEMENT) birth cohort followed up to three time points. Dietary Approaches to Stop Hypertension (DASH), alternate Mediterranean Diet (aMedDiet), and Children’s Dietary Inflammatory Index (C-DIITM) scores were computed from food frequency questionnaires. Higher DASH and aMedDiet scores reflect a higher diet quality, and lower C-DII scores reflect an anti-inflammatory diet. Cardiometabolic risk factors were lipid profile, glucose homeostasis, blood pressure, and waist circumference. Linear mixed models were used between quartiles of each diet score and outcomes. Compared to the first quartile, the fourth DASH quartile was inversely associated with log serum insulin (μIU/mL) [β = −0.19, p = 0.0034] and log-Homeostatic Model Assessment of Insulin Resistance [β = −0.25, p = 0.0008]. Additionally, log serum triglycerides (mg/dL) was linearly associated with aMedDiet score [β = −0.03, p = 0.0022]. Boys in the highest aMedDiet quartile had higher serum high-density lipoprotein cholesterol (mg/dL) [β = 4.13, p = 0.0034] compared to the reference quartile. Higher diet quality was associated with a better cardiometabolic profile among Mexican youth.

Serum Vitamin D Levels in Relation to Abdominal Obesity in Children and Adolescents: A Systematic Review and Dose-Response Meta-Analysis

Background

Findings of epidemiological studies that investigated the relationship between serum vitamin D levels and abdominal obesity were inconsistent. To evaluate the relationship between blood vitamin D levels and abdominal obesity in children and adolescents, we did a comprehensive review and dose-response meta-analysis.

Methods

A comprehensive search in electronic databases including Scopus, Web of Science (ISI), MEDLINE (Pubmed), EMBASE, and Google Scholar was conducted, up to May 2021, for epidemiological studies that investigated the linkage between serum vitamin D levels (as the exposure) and abdominal obesity (as the outcome) in children and adolescents.

Results

Combining 19 effect sizes from 14 cross-sectional studies that included 29,353 apparently healthy children illustrated that the highest vs. lowest level of serum vitamin D was related to a 35% reduced odds of abdominal obesity [odds ratio (OR): 0.65; 95% CI: 0.50, 0.84]. Linear dose-response analysis revealed that each 10 ng/ml increase in serum vitamin D levels was related to a 7% decrease in odds of abdominal obesity (OR: 0.93; 95% CI: 0.90, 0.95), only among investigations that used percentiles of waist circumference (>75th or 90th) to define the disorder (including 6,868 total subjects and 1,075 cases with abdominal obesity). Increasing serum vitamin D levels from 20 to 40 ng/ml was related to reduce odds of abdominal obesity in children.

Conclusion

A negative relationship between blood vitamin D levels and abdominal obesity in children and adolescents was discovered in this meta-analysis of epidemiologic studies. Among investigations that used waist circumference percentiles to define the disorder, the relationship was in a dose-response manner. To affirm this relationship, more research studies are needed, particularly using a prospective design.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021261319, PROSPERO 2021, identifier: CRD42021261319.

Effects of body geometry, body composition, cardio-pulmonary capacity, and fitness on young men's thermal preference

This paper investigated principal parameters affecting individual differences of thermal preference. 36 male college students were selected from three thermal preference groups by a questionnaire, including 10 of cool preference (Gcp), 17 of neutral preference (Gnp), and 9 of warm preference (Gwp). Subsequently, their thermal preferences were further examined by a human trial in a climate chamber. Once significant differences were found between groups, subjects' 57 parameters, including body geometry, body composition, cardio-pulmonary capacity, and physical fitness, were measured. Compared to Gwp, Gcp had higher weight (80.0 vs. 64.2 kg), body mass index (BMI) (26 vs. 20.8 kg·m^-2 ), body surface area (BSA) (1.94 vs. 1.78 m² ), waist-to-hip ratio (WHR) (87.29% vs. 80.23%), body circumferences (except for forearm circumference), skinfold thickness of all the local parts, volume of expired air (VE) (50.97 vs. 40.81 L/min), and body fat rate (BFR) (24.44% vs. 14.07%), but had a lower specific surface area (SSA) (0.02477 vs. 0.02791 m² /kg), resting metabolic rate (RMR) per kilogram (1.21 vs. 1.47 W/kg), diastolic blood pressure (DBP) (65.30 vs. 74.69 mmHg), and percentages of muscle (71.17% vs. 80.95%), total water (55.35% vs. 63.14%), skeletal muscle (42.47% vs. 47.94%), protein (14.90% vs. 16.94%), inorganic salt (5.29% vs. 5.86%), and bone mineral (0.044% vs. 0.048%). Among these parameters, body fat and SSA played a dominant role (accounting for 85.76%) in explaining individual differences in thermal preference.

Cardiorespiratory fitness, screen time and cardiometabolic risk in South Brazilian school children

Background: Cardiorespiratory fitness (CRF) is considered a beneficial effect of physical activity (PA). PA and excessive screen time have implications for cardiometabolic risk. Objective: To verify the association between screen time and CRF grouped by cardiometabolic risk factors. Subjects and methods: Cross-sectional study evaluated 1,253 schoolchildren (54.2% girls) aged seven to 17 years from southern Brazil. The outcomes were body mass index (BMI), waist circumference (WC), systolic (SBP) and diastolic (DBP) blood pressure, glucose, and lipid profile. Exposure was a combined variable of self-reported screen time (television, video game, computer) and CRF. Results: The main result is that CRF had a more consistent association with anthropometric factors than with metabolic variables. Low CRF students, regardless of screen time, showed a 15% increase in the risk of elevated WC (p < 0.001) and a 24% (<2h screen time) and 19% (≥2h) higher risk of overweight (p < 0.001). Second, the increase in SBP was associated with a combination of the two risk factors, ≥2h screen time/low CRF was associated with a 7% increase in elevated SBP (p = 0.025). Conclusion: Low CRF was a risk factor for elevated BMI and WC, regardless of screen time. High screen time and low CRF were associated with higher SBP values.

The association between modifiable lifestyle behaviour in Latin-American schoolchildren with abdominal obesity and excess weight. A comparison of Chile and Colombia

OBJECTIVE

The purpose was to determine the association of lifestyle (i.e., Mediterranean diet [MD] adherence, physical activity [PA], screen time [ST]) and fitness with abdominal obesity (AO) and excess weight in the Chilean and Colombian schoolchildren.

RESEARCH METHODS & PROCEDURES

This cross-sectional study included 969 schoolchildren, girls (n=441, 5.24±0.80 years old) and boys (n=528, 5.10±0.78 years old) from Chile (n=611) and Colombia (n=358). The body mass index (BMI), waist circumference (WC), waist-to-height ratio (WtHR), MD adherence, PA, ST and cardiorespiratory fitness (CRF) were evaluated. The association of AO and anthropometric variables with lifestyle was estimated through multiple linear regression. To determine the association between AO and lifestyle, a logistic regression and the inclusion of odds ratios (ORs) with 95% confidence intervals (CIs) were used.

RESULTS

Worse CRF in Chilean children were positively correlated with WC. Excess weight in Chilean and Colombian children was positively associated with an unhealthy lifestyle. In Chilean children unhealthy lifestyle was also associated with AO based on WC≥85th percentile and AO based on WtHR≥85th percentile. In Chilean children, excess weight (BMI≥85th percentile) was positively associated with poor MD adherence.

CONCLUSION

AO and excess weight were associated with an unhealthy lifestyle in Latin-American schoolchildren. Interventions to reduce the prevalence of AO should include promoting healthier lifestyle choices (i.e., increasing PA after school, reducing ST and improving CRF).