Waist Circumference In Children Research Articles

Longitudinal relationship between screen time, cardiorespiratory fitness, and waist circumference of children and adolescents: a 3-year cohort study

PurposeThe aim of this study was to examine the interaction between screen time and cardiorespiratory fitness (CRF) in their longitudinal association with waist circumference (WC) during a follow-up of 3 years from childhood to adolescence.MethodsObservational 3-year longitudinal study with 401 students (224 females), seven to 15 years of age at baseline. The CRF was evaluated by estimating peak oxygen uptake (VO2peak) from an indirect field-based test and body mass index. Screen time was assessed using self-reported questionnaires. Moderation analyses were tested using a multiple linear regression model with adjustments for sex, age, puberty stage, and ethnicity.ResultsA statistically significant interaction term was observed (B = -0.0003; 95% CI: -0.007; -0.0001). Since screen time was contextualized as the independent variable, the results show that relationship between screen time and WC varies across different CRF levels.ConclusionThe findings suggest that higher CRF can attenuate the harmful association that increased sedentary behavior might have on abdominal adiposity.

Delayed bedtime on non-school days associates with higher weight and waist circumference in children: Cross-sectional and longitudinal analyses with Mendelian randomisation.

Sleep duration has been linked with obesity in population-based studies. Less is known about bedtimes and, especially, if discrepancy between bedtimes on school and non-school days associate with adiposity in children. The associations of self-reported bedtimes with the body mass index z-score (BMIz) and waist-to-height ratio (WtHr) were examined among children with a mean (SD) age of 11.2 (0.85) years in cross-sectional (n=10,245) and longitudinal (n=5085) study settings. The causal relationship of whether BMIz contributes to bedtimes, was further examined in a subset of 1064 participants by exploiting Mendelian randomisation (MR). After adjusting for sleep duration and other confounders, every 0.5 h later bedtime on non-school nights and a delay in bedtime in non-school nights compared with school nights associated with 0.048 (95% CI 0.027; 0.069) and 0.08 (95% CI 0.056; 0.105) higher BMIz as well as 0.001 (95% CI 0; 0.002) and 0.004 (95% CI 0.003; 0.005) with higher WtHr, respectively. Moreover, every 0.5-h delay in bedtime in non-school nights compared with school nights associated with 0.001 (95% CI 0; 0.002) greater increase in WtHr in the 2.5 years follow-up. Thus, a 2-h delay in bedtime at the age of 11 years corresponds with a 0.6 cm increase in waist circumference. The MR analysis did not indicate an opposite causal relationship: higher BMIz was not causing delayed bedtimes. Later bedtime on non-school days and discrepancy in bedtimes associated with increased BMIz and WtHr, while longitudinally these predicted higher WtHr, independently of sleep duration. Promoting early bedtimes, especially on weekends, should be considered in obesity prevention among school-aged children.

Associations of childhood adiposity with adult intima-media thickness and inflammation: a 20-year longitudinal population-based cohort.

The associations between childhood adiposity and adult increased carotid intima-media thickness (cIMT) have been well established, which might be corroborated by the association between adiposity in children and inflammation in adults. However, longitudinal data regarding biological pathways associated with childhood adiposity are lacking. The current study included participants from the STANISLAS cohort who had adiposity measurements at age 5-18 years [ N = 519, mean (SD) age, 13.0 (2.9) years; 46.4% male], and who were measured with cIMT, vascular-related and metabolic-related proteins at a median follow-up of 19 ± 2 years. BMI, waist-to-height ratio and waist circumference were converted to age-specific and sex-specific z -scores. A minority of children were overweight/obese (16.2% overweight-BMI z -score >1; 1.3% obesity- z -score >2). Higher BMI, waist-height ratio and waist circumference in children were significantly associated with greater adult cIMT in univariable analysis, although not after adjusting for C-reactive protein. These associations were more pronounced in those with consistently high adiposity status from childhood to middle adulthood. Participants with higher adiposity during childhood (BMI or waist-height ratio) had higher levels of insulin-like growth factor-binding protein-1, protein-2, matrix metalloproteinase-3, osteopontin, hemoglobin and C-reactive protein in adulthood. Network analysis showed that IL-6, insulin-like growth factor-1 and fibronectin were the key proteins associated with childhood adiposity. In a population-based cohort followed for 20 years, higher BMI or waist-to-height ratio in childhood was significantly associated with greater cIMT and enhanced levels of proteins reflective of inflammation, supporting the importance of inflammation as progressive atherosclerosis in childhood adiposity.

Reference Ranges of Age-Based Liver, Spleen, Pancreas, and Kidney Size in Conjunction with Waist Circumference in Children

Objective: In the initial phases of parenchymal diseases, the only finding would be an increase in organ size. We aimed to provide percentile charts of solid intraabdominal organ sizes by age for Turkish children on contrast-enhanced computed tomography images and reveal relative size ratios.Materials and Methods: A total of 800 abdominal computed tomography examinations of otherwise healthy children (468 males, 332 females) were enrolled. The transverse diameter and lengths of both liver lobes, the thickness of the pancreas, width and length of the spleen, and anteroposterior diameters and lengths of both kidneys were measured. Differences in mean diameters among ages were compared with the analysis of variance test. Pearson’s correlation was assessed to depict the association of size with age and waist circumference.Results: Percentile charts for all measured size parameters that presented statistically significant positive correlations with age and waist circumference were provided. There were constant ratios of the right liver lobe to the left liver lobe (1.9 ± 0.37), right liver lobe to the right kidney (1.56 ± 0.26), left to the right kidney (1.03 ± 0.09), and spleen to the left kidney (1 ± 0.2) lengths in every age groups. Age (years)-dependant regression equation for waist circumference (mm) was depicted as “22 × age + 408.”Conclusion: Age-based percentile charts of solid intraabdominal organ diameters along with relative organ size ratios were provided.

Nutrient intake, dietary patterns, and anthropometric variables of children with ADHD in comparison to healthy controls: a case-control study

BackgroundPoor health behaviors and variables are recently more documented in attention-deficit hyperactivity disorder (ADHD) lifestyle which might be relevant to the pathophysiology of this disorder. The objective of this case-control study was to assess the nutrient intake, dietary patterns, and anthropometric variables in children with ADHD compared to normal peers.MethodOne hundred children diagnosed with ADHD were included and compared to 100 healthy, sex-matched normal children as the control group. Anthropometric indices, macronutrients, and micronutrients were measured and compared in both groups.ResultsADHD children were significantly consuming more simple sugars, tea, ready-made meals but less protein, vitamin B1, vitamin B2, vitamin C, zinc and calcium compared to the control group. The body mass index (BMI) and waist circumference of children with ADHD were significantly higher and were related to the severity and type of the disease.ConclusionUnhealthy eating behavior is more frequent in children with ADHD, compared to normal children which might warrant lifestyle intervention in this disorder.

Snack Food Consumption across the Pune Transect in India: A Comparison of Dietary Behaviors Based on Consumer Characteristics and Locations.

This study examines patterns of snack food consumption (SFC) in the rural-urban-slum transect (RUST) of a large city Pune and its precincts (population 10 million) in India. The transect structure aims to mimic a representative survey for the location capturing differences by age, gender, urbanicity, and socio-economic levels. Dietary data from 1405 individuals were used to describe snacking patterns and other food consumed at different frequencies; extent of physical activity; and Body Mass Index (BMI) and waist circumference of children, adolescents, and adults. Our results indicate high incidence of SFC across all population age groups, gender, socio-economic levels, and locations. A distinctive finding in relation to studies in high income countries is the prevalence of hunger snacking with 70% identifying hunger as the primary reason for SFC. Apart from hunger, particularly for adolescents, peer influence and social interactions played a significant role in SFC. Dietary behaviors of slum dwellers were characterized by three-quarters of them having SFC together with family members at home. SFC supplemented calories for low-income consumers and complemented calorie intake for high income ones. No significant association with BMI is possibly due to obesogenic SFC being likely offset by lower consumption of non-snack food and higher physical activity among poor and slum dwellers. Promoting awareness about diets and lifestyles, improving physical and economic access to healthier snacks and nutrient dense foods can improve diet quality in a large and heterogeneous population such as Pune.

Obesity and Waist Circumference in Children: Indicators of Cardiometabolic Risk

Obesity and Waist Circumference in Children: Indicators of Cardiometabolic Risk

Evaluation of the Prevalence of Vitamin D Deficiency and itsâ Correlation with Body Mass Index and Waist Circumference in Children

Introduction: Recent studies have suggested a link between vitamin D deficiency and an increase in body mass index and waist circumference. The aim of this study was to evaluate the vitamin D status and its’ correlation with body mass index and waist circumference in children aged 2-14 referred to the clinic of Imam Ali Hospital in Karaj in 2019-2020. Methods: Three Hundred seventy-nine (379) children aged 2-14 years referred to Clinic were enrolled in the study. Patients' height, weight (BMI calculated accordingly), waist circumference and serum vitamin D levels were measured. Chi-Square, Krystal-Wallis and Fishers exact tests were used, and the Bivariate Correlation test was used to determine the relationship between two variables. Results: The prevalence of vitamin D deficiency, insufficiency and adequate levels were reported 40.6%, 11.9%and 47.5%, respectively. Vitamin D deficiency was more common in girls. Vitamin D had a significant and weak relationship with BMI, but no association with waist circumference. Conclusion: The results of this study showed a high prevalence of vitamin D deficiency in patients. The prevalence of vitamin D deficiency and insufficiency were higher in girls. The highest levels of vitamin D were found in patients with normal weight. Vitamin D deficiency was most common in obese patients. Serum vitamin D were significantly associated with obesity, but had no significant association with waist circumference. A study with a larger sample size in this area, is recommended.

Birth weight, cardiometabolic risk factors and effect modification of physical activity in children and adolescents: pooled data from 12 international studies

ObjectivesLow and high birth weight is associated with higher levels of cardiometabolic risk factors and adiposity in children and adolescents, and increases the risk of cardiovascular diseases, obesity, and early mortality later in life. Moderate-to-vigorous physical activity (MVPA) is associated with lower cardiometabolic risk factors and may mitigate the detrimental consequences of high or low birth weight. Thus, we examined whether MVPA modified the associations between birth weight and cardiometabolic risk factors in children and adolescents.MethodsWe used pooled individual data from 12 cohort- or cross-sectional studies including 9,100 children and adolescents. Birth weight was measured at birth or maternally reported retrospectively. Device-measured physical activity (PA) and cardiometabolic risk factors were measured in childhood or adolescence. We tested for associations between birth weight, MVPA, and cardiometabolic risk factors using multilevel linear regression, including study as a random factor. We tested for interaction between birth weight and MVPA by introducing the interaction term in the models (birth weight x MVPA).ResultsMost of the associations between birth weight (kg) and cardiometabolic risk factors were not modified by MVPA (min/day), except between birth weight and waist circumference (cm) in children (p = 0.005) and HDL-cholesterol (mmol/l) in adolescents (p = 0.040). Sensitivity analyses suggested that some of the associations were modified by VPA, i.e., the associations between birth weight and diastolic blood pressure (mmHg) in children (p = 0.009) and LDL- cholesterol (mmol/l) (p = 0.009) and triglycerides (mmol/l) in adolescents (p = 0.028).ConclusionMVPA appears not to consistently modify the associations between low birth weight and cardiometabolic risk. In contrast, MVPA may mitigate the association between higher birth weight and higher waist circumference in children. MVPA is consistently associated with a lower cardiometabolic risk across the birth weight spectrum. Optimal prenatal growth and subsequent PA are both important in relation to cardiometabolic health in children and adolescents.

Non-alcoholic fatty liver disease in children: relationship with the main components of metabolic syndrome in children

There is a high frequency of combination of components of metabolic syndrome (MS) and liver damage in obese patients.Of interest is the study of clinical and pathogenetic relationships between the morphofunctional state of the liver and the development of MS in children.Objective: to Study the functional state of the liver in children with MS and to assess the relationship with its main components.Materials and methods. 483 obese children (SDS BMI≥2.0) aged from 5 to 16 years (285 boys and 198 girls) were examined: I gr. — 237 children with MS, II gr. — 246 obese children without MS. Comprehensive examination included anamnesis, anthropometry, clinical and biochemical blood tests, lipid spectrum and carbohydrate metabolism, ultrasound examination of the abdominal cavity and retroperitoneal space, CT of the abdominal cavity. Statistical processing of the results was carried out using the package «STATISTIKA 6.0».Research result. Ultrasound-signs of nonalcoholic fatty liver disease (NAFD) in I gr. revealed significantly more often than in II gr. (166 — 70% and 125 — 51%, respectively, p<0.05). The majority (91%) of children with NAFD are 10–16 years old. Boys slightly more than girls (58% and 42%). The increase of ALT in the I gr. it was registered at 27% of children, in II gr. — in 18% of children (p<0.05). Increase of ALT in boys was detected 2 times more often than in girls (26% and 13%, p<0.05). In patients with NAFLD, regardless of the group, signs of atherogenic dyslipidemia (increased triglycerides, decreased HDL), impaired carbohydrate metabolism (insulin, C‑peptide and IR index) were more often diagnosed. A higher frequency of hyperglycemia in children I gr. was established. regardless of the liver condition (68% of children without NAFLD and 69% of children with NAFLD), whereas in II gr. it was registered more often in the presence of NAFLD (16% and 8%). In both groups, the level of MC in children with NAFLD was higher than without it, and in I gr. this indicator was significantly higher than in children of II gr. Mean fibrinogen levels were also higher in children with NAFLD, and these differences were significantly significant in I gr.Conclusion.1. Ultrasound criteria for NAFLD in children with MS are diagnosed significantly more often (70%) than in children with uncomplicated obesity (51%).2. CT-changes in liver parenchymain NAFLD are characterized by the presence of diffuse focal process with the presence of different sites with changes in the type of fatty dystrophy and steatohepatitis against the background of unchanged parenchyma.3. Adolescents over 12 years of age and males predominate among children with NAFLD.4. Waist circumference in children with NAFLD, regardless of the group, significantly exceeds that of children without it, which indicates the relationship of functional disorders of the liver with the development of abdominal typeof obesity — the main component of MS.5. Hyperfermentemia in the form of increased ALT levels is most often registered in children with MS in the presence of NAFLD (27%), in 15% of them the values exceed the normative indicators by 1.5 or more times, which indicates a high risk of developing an inflammatory process of the type of steatohepatitis.6. Lipid metabolism disorders in the form of an increase in TG and a decrease in HDL in children with NAFLD are recorded more often than in children without it, regardless of the presence of MS, but their combination is diagnosed exclusively in children with MS: in children with NAFLD — in 29% of cases, without it — in 23%.7. Regardless of the group, changes in carbohydrate metabolism in the presence of NAFLD were more pronounced than in children without it, while children with MS and NAFLD showed a more significant increase in glycemia, insulin and IR index.8. Children with MS and NAFLD have a higher incidence of purine metabolism disorders.9. A correlation between hepatic metabolism and disorders in the fibrinolysis system, which progress with the duration of the disease, was obtained.

Correlates of body fat and waist circumference in children from São Caetano do Sul, Brazil.

The purpose of this study was to examine potential correlates of body fat (BF) and waist circumference (WC) in children. The sample included 328 children (169 boys) aged 9-11 years. BF (%) was measured using a bioelectrical impedance scale. WC measurements were made on exposed skin at the end of a normal expiration using a non-elastic anthropometric tape. Moderate-to-vigorous physical activity (MVPA) and sedentary behavior were measured using accelerometers. Participants with complete individual, family and home, and school environmental data were included in the analysis. Children averaged 21.3% in boys and 25.8% in girls for BF and 68.0 cm in boys and 67.2 cm in girls for WC. There was higher BF among girls (p<0.001), but no significant sex differences with respect to WC. In boys, breakfast consumption, bad sleep quality, and MVPA were associated with BF. Among girls, the only variables associated with BF were breakfast consumption and bad sleep quantity. Bad sleep quality and MVPA were associated with WC in boys. Among girls, WC was associated with breakfast consumption and bad sleep quantity. We identified correlates of BF and WC in children; however, few correlates were common for both BF and WC, and for both boys and girls.

Diferencias antropométricas de escolares de 5 y 6 años en colegio público y privado, Chile 2015

Introducción: La obesidad infantil representa un problema de salud pública a nivel mundial. Chile presenta una de las tasas más altas de prevalencia de obesidad infantil de Latinoamérica. Localmente, hay pocos estudios que muestran las diferencias entre colegios públicos y privados en relación a parámetros de peso, talla y perímetro de cintura en escolares. El objetivo de este estudio es determinar si existen diferencias antropométricas de niños de 5 y 6 años según el tipo de colegio.Material y métodos: Se realizó una investigación cuantitativa, descriptiva y transversal. Se constituyó una muestra no probabilística de 195 niños de 5 y 6 años, los cuales 55 corresponden a colegio público y 140 a colegio privado. Resultados: En la valoración antropométrica de niños entre 5 y 6 años de colegios públicos y privados, los escolares en peso y talla en ambas edades no fueron estadísticamente significativas (p&gt;0,05), sin embargo, la población en conjunto, sin diferenciar en edades, fueron estadísticamente significativas en la talla (p&lt;0,05). Los valores de IMC para 5 y 6 años se encuentran bajo los puntos de corte de obesidad definidos internacionalmente y fueron estadísticamente significativas entre colegio público y privado (p&lt;0,05). En perímetro de cintura, los escolares de colegios públicos tuvieron más escolares sobre el Percentil 90, catalogado como obesidad abdominal. Sin embargo, estas diferencias encontradas no fueron estadísticamente significativas (p&gt;0,05). Conclusiones: Se evidenció menor talla (p&lt;0,05), mayor peso y mayor perímetro de cintura en escolares de colegio público en relación a privado, sin embrago dado la baja participación de colegios y diferencia de tamaño muestreal en ambos grupos, estas diferencias deben ser interpretadas con cautela.

Competency Based Approach to Community Health (COACH): The methods of a family-centered, community-based, individually adaptive obesity randomized trial for pre-school child-parent pairs

Competency-Based Approaches to Community Health (COACH) is a randomized controlled trial of a family-centered, community-based, and individually-tailored behavioral intervention for childhood obesity among Latino pre-school children. COACH focuses on improving personal agency for health behavior change by tailoring content to overcome contextual barriers. The intervention focuses on diet, physical activity, sleep, media use, and engaged parenting. The content is individually adapted based on routine assessments of competency in specific health behaviors using a mobile health platform and novel measurement tools developed by our team. In response to these regular assessments, health coaches provide tailored health behavior change strategies to help families focus on the areas where they decide to improve the most. The intervention consists of a 15-week group-based intensive phase, with weekly sessions delivered by health coaches in community centers. Following weekly sessions, a 3-month maintenance phase of the intervention consists of twice monthly coaching calls for participants to focus on individual health goals for their families.The primary outcome of the trial is child body mass index trajectory over 1 year. Secondary outcomes include parent body mass index change, child waist circumference, child diet, child physical activity, and other psychosocial mediators of child health behavior change. The control arm consists of a school readiness intervention, delivered by the Nashville Public Library.By applying a personalized approach to child behavior change, in the setting of both family and community, COACH aims to develop sustainable solutions for childhood obesity by supporting healthy childhood growth in low-income, minority preschool children.

Epidemiological characteristics of waist circumference and abdominal obesity among Chinese children and adolescents aged 6-17 years

Objective: To analyze the epidemiological characteristics of waist circumference and abdominal obesity among Chinese children and adolescents aged 6-17 years. Methods: Data was from the samples of aged 6-17 years in the China National Nutrition and Health Surveillance program in 2010-2012. P(90) (the same age, the same sex) was used as the diagnostic value for abdominal obesity. Results: The overall waist circumference of children and adolescents in all the age groups appeared higher in males than that in females (P<0.000 1), higher in cities than that in the rural areas (P<0.05), and higher in children with high family income than those with middle or low family incomes (P=0.000 3). The rate of abdominal obesity in children and adolescents aged 6-17 years appeared as 11.2% on average and 10.7% and 11.8% for boys and girls, respectively but with no significant difference (P>0.05). Rates on abdominal obesity appeared as 13.2% and 8.5% for boys while as 12.3% and 11.2% for girls respectively, in urban or rural areas. As for the levels of family income, the abdominal obesity rates appeared as 15.8%, 11.5% and 8.8% respectively for boys while 13.5%, 11.9% and 11.6% respectively for girls, under high, middle and low levels of family income. Conclusion: The rate of abdominal obesity in boys seemed more responsive to the impact of income in urban or rural areas.

The Changes of Body Surround Degree and the Relationship with the Movement Scheme—An Intervention Program on Diet and Exercise

Objective: To explore the rule of the surrounded degree changes in different parts of the body and the relationship between exercise intervention plan and the surrounded degree changes during eight weeks of exercise with the diet intervention in obese children. Methods: Selecting one primary school in Beijing 25 obese students who are on 4-5 grade as the subjects. Weekly measured and record the obese child's upper arm circumference, waist, hip, thigh circumference and crus surrounds. The time and place are fixed, and use the same flexible rule. It was asked that boy wearing boxer shorts, upper body without clothes, girls wear boxer shorts, wearing the vest that show hilum when were tested. Exercise intervention was combined with power resistance and aerobic strength training. For power resistance training, it was 4 times a week, each time 20 mins (4 weeks before) - 25 min (4 weeks later), and exercise intensity was 50% 1 RM; Aerobic training was five times a week, for the fourth weeks, each training was 25 mins, exercise intensity was 60% HRmax, while 4 weeks later, it was adjusted training time to 20 min, 70% HRmax. Tracking measurement for eight times, measurement data were analyzed by generalized estimation model. Results: (1) the obese child's waist circumference, hip circumference, upper arm circumference, thigh circumference and crus surrounds surrounded degree of five parts of the body with gradually reduce with the measurement time. Compared with the baseline, in the late intervention the average waistline reduce 10.4 cm; Hip circumference mean lower 7 cm; Thigh circumference average decline in 3 cm; Crus surrounds average drop of 1.8 cm; Hiplines average by 1.7 cm.(2)During 8 weeks of exercise and dietary interventions, obese children body surround degree of each part in the order: upper arm circumference, waist, hips, thighs, legs around.(3) The size of obese child's body surrounded degree percentage change is: waist &gt; the upper arm &gt; hip circumference &gt;calf circumference&gt; thigh circumference, and each part of the surrounded degree changes has significant difference (P&lt;0.05). Conclusion: 1, during 8 weeks of exercise and dietary interventions, the most easily reduction of obese children body is waist and abdomen and thigh, the upper arm followed, the hardest to cut is the calf. Suggestions are that when making the exercise prescription of losing weight may vary according to each area need a scientific planning of the shortest time in the future.2, 8 weeks exercise with the diet intervention, the various body parts of the obese children surrounded degree all have significant changes, from the effect of intervention, the most obvious change is the waist and upper arm, the thigh is not obvious. Exercise 3, accumulation of exercise time of the body is the important factors that affect body surrounded degree changes.

Direct and indirect effects of parent stress on child obesity risk and added sugar intake in a sample of Southern California adolescents.

Research indicates that children are at higher risk for obesity if their parents have been exposed to a larger number of stressors, yet little is known about effects of parents' subjective, perceived experience of stress on children's eating behaviours and adiposity and whether weight-related parenting practices (i.e. parent rules and positive family meal practices) mediate this relationship. The present study evaluated the direct and mediated relationship between parent perceived stress and child waist circumference and parent stress and child consumption of added sugars one year later. Longitudinal panel data. Eleven communities in Southern California, USA. Data were collected over two waves from parent-child dyads (n 599). Most parents were female (81 %) and Hispanic (51 %); children were 11 years old on average (sd 1·53; range 7-15 years) and 31 % received free school lunch. Perceived parent stress was not significantly associated with child waist circumference or consumption of added sugars one year later, and mediating pathways through parenting practices were not significant. However, parent rules were significantly associated with lower child consumption of added sugars (β=-0·14, P<0·001). Results suggest that parent rules about the types of foods children can eat, clearly explained to children, may decrease child consumption of added sugars but not necessarily lead to changes in obesity risk. Parent- and family-based interventions that support development of healthy rules about child eating have the potential to improve child dietary nutrient intake.

Scaling children's waist circumference for differences in body size

Both waist circumference (WC) and body size (height) increase with age throughout childhood. Hence, there is a need to scale WC in children to detect differences in adiposity status (eg, between populations and different age groups), independent of body size/height. Using two culturally different samples, 1 English (10-15.9 years n = 9471) and 2 Colombian (14-15 years, n = 37,948), for WC to be independent of height (HT), a body shape index was obtained using the allometric power law WC = a.HTb . The model was linearized using log-transformation, and multiple regression/ANCOVA to estimate the height exponents for WC controlling for age, sex, and any other categorical/population differences. In both samples, the power-law height exponent varied systematically with age. In younger children (age 10-11 years), the exponent was approximately unity, suggesting that pre-pubertal children might be geometrically similar. In older children, the height exponent declined monotonically to 0.5 (ie, HT0.5 ) in 15+ year-olds, similar to the exponent observed in adults. UK children's height-adjusted WC revealed a "u" shaped curve with age that appeared to reach a minimum at peak-height velocity, different for boys and girls. Comparing the WC of two populations (UK versus Colombian 14-15-year-old children) identified that the gap in WC between the countries narrowed considerably after scaling for height. Scaling children's WC for differences in height using allometric modeling reveals new insights into the growth and development of children's WC, findings that might well have been be overlooked if body size/height had been ignored.

Cross-sectional and prospective associations between physical activity, body mass index and waist circumference in children and adolescents.

SummaryObjectiveTo study the cross‐sectional and prospective associations between physical activity (PA) of different intensities, body mass index (BMI) and waist circumference (WC) in children and adolescents using isotemporal substitution modelling.MethodsPhysical activity (accelerometry), BMI and WC were assessed in 6‐ (n = 970), 9‐ (n = 2,423) and 15‐year‐olds (n = 1,544) in 2005/2006 and 2011/2012. Participants aged 9 years in 2005/2006 were followed prospectively to 2011/12 (age 15). Associations between PA of different intensities (light, moderate and vigorous), BMI and WC were examined using isotemporal substitution models.ResultsSubstituting 10 min per day of sedentary time with light PA was associated with higher WC (0.17 to 0.29 cm, p ≤ 0.003)) in all age groups. Substituting 10 min per day of sedentary time with moderate PA was associated with lower WC in 6‐ and 9‐year‐olds (−0.32 to −0.47 cm, p ≤ 0.013)). Substituting 10 min per day of sedentary time with vigorous PA was associated with lower WC in 9‐ and 15‐year‐olds (−1.08 to −1.79 cm, p ≤ 0.015)). Associations were similar with BMI as the outcome. In prospective analyses, substituting sedentary time with light, moderate or vigorous PA at age 9 was not associated with BMI or WC at age 15.ConclusionSubstituting sedentary time with moderate PA appears favourably associated with adiposity in children, whereas vigorous PA may be required in adolescents. Cross‐sectional associations were not replicated in prospective analyses.

Effectiveness of the Children's Healthy Living (CHL) Multilevel Multicomponent Community Intervention Program in 5 US affiliated Pacific Jurisdictions

The Children's Healthy Living (CHL) program, a collaboration among Pacific Land Grant Colleges, was developed and implemented with 27 communities across the US affiliated Pacific region in a 24 month community randomized intervention trial to prevent young child obesity. The multilevel, multisite, community‐based intervention consisted of 4 cross‐cutting functions (initiate or strengthen school wellness policies; partner and advocate for environmental change; promote CHL messages; and local capacity building) with 20 activities addressing 6 targeted behaviors (physical activity, sedentary behavior, sleep, fruit and vegetable intake, sugar sweetened beverage intake, and water intake). A common intervention template and outcome measures were developed and implemented; IRB approval or ceding of approval was obtained at each of the 5 collaborating institutions. Controlling for age and sex of 2–10 year old children and accounting for the randomization units and clustering, the CHL intervention communities had significant changes in the following variables compared to control communities: prevalence of acanthosis nigricans (change of −0.1% vs +0.2%), child overweight plus obesity (−3.0% vs +1.7%), child waist circumference (+0.2cm vs +9cm), and daily screen time (−2.4min vs +3.0mins). Accelerometry and food related variables (fruit and vegetable intake, sugar sweetened beverage intake, water intake) are still being analyzed. The results indicate that community‐based multilevel multi‐component interventions can impact young child overweight and obesity and related behaviors and conditions.Support or Funding InformationUSDA/NIFA grant 2011‐68001‐30335

Cumulative Risk Exposure and Waist Circumference in Preschool-Aged Children: the Mediating Role of Television and Moderating Role of Sex.

Children exposed to multiple stressors are more likely to be overweight, but little is known about the mechanisms explaining this association. This cross-sectional study examined whether children exposed to multiple stressors had higher waist circumference, and whether this association was mediated through children's television time. Participants were 319 parent-child dyads. Children were 2-5years old and had at least one overweight parent (BMI≥25kg/m2). Data were collected at baseline of a larger childhood obesity prevention study and included information on psychosocial stressors (e.g., parenting stress), demographic stressors (e.g., low income), children's television time, and children's waist circumference. Two cumulative risk scores were created by summing stressors in each domain (demographic and psychosocial). Mediation and moderated mediation analyses were conducted. Indirect effects of both cumulative risk scores on waist circumference through television time were not significant; however, moderated mediation analyses found significant moderation by gender. The indirect effects of both risk scores on waist circumference through television time were significant and positive for girls, but near-zero for boys. Reducing television time should be explored as a strategy for buffering against the negative health effects of exposure to multiple stressors among girls. Longitudinal and intervention research is needed to confirm these results and to identify mediating factors between cumulative risk and body weight among boys.