北京市3～18岁人群腰围和腰围身高比分布特征及其适宜界值的研究

目的 研究北京市3～18岁人群腰围（WC）、腰围身高比（WHtR）的分布特征；在心血管疾病（CVD）危险因素评估的基础上提出6～18岁人群WC和WHtR的适宜界值。方法 对2004年北京市儿童青少年代谢综合征研究项目总人群中3～18岁人群的WC、WHtR进行描述性分析；基于CVD危险因素评估，采用工作者特征曲线分析方法，研究6～18岁人群WC和WHtR的适宜界值；并利用《北京市学校卫生防病工作规划》（2006）血脂健康调查中6~17岁人群生理、生化检测数据，对上述界值进行交叉验证。结果 基于CVD危险因素评估基础上的WC适宜界值为性别年龄组的第80百分位值，WHtR的适宜界值为0.46。交叉验证显示：按WC和WHtR适宜界值划分的肥胖组血压、血脂等CVD危险因素无论均值还是检出率均显著高于正常体重组。结论 上述WC、WHtR适宜界值可敏感地区分高血压、高三酰甘油和低高密度脂蛋白胆固醇等CVD危险因素，WC作为相对简单的测量方法应列入学生体检的常规测量项目。     

Waist circumference in relation to body perception reported by Finnish adolescent girls and their mothers

Aim: To study how waist circumference (WC) relates to body perception in adolescent girls and to maternal perception of the girl's body size.
Methods: Three hundred and four girls, 11–18 years, were measured for height, weight and WC. 294 girls provided self-report data on weight, height and body image before anthropometric measurements. Paired data from 237 girls and mothers on perception of the girls' body size were collected.
Results: In girls, self-reported weight indicated awareness of actual body size. The girls' body perception showed an overestimation of body size relative to international reference values for body mass index (BMI) (p < 0.05), but not for WC. Girls' body perception exceeded that of their mothers (p < 0.05). Maternal perception agreed better than the girls' perception with international reference values for BMI (p < 0.05). No significant difference between mothers and girls were found concerning agreement of body perception with international reference values for WC.
Conclusion: WC rather than BMI agrees with perception of body size, possibly due to its relation to abdominal fat at different ages. For effective prevention and treatment programmes for weight-related health problems among adolescent girls, we recommend measuring WC to diminish the discrepancy between measured and perceived body size.     

Waist circumference for the screening of the metabolic syndrome in children

Aim: To identify the best anthropometric predictor of the metabolic syndrome in children. Methods: Screening performance was evaluated in a clinical setting. The study included 140 children: 72 non-obese and 68 with non-syndromal obesity. Body mass index (BMI), waist circumference and triceps/subscapular skinfolds ratio were used as predictor variables, and systolic blood pressure, diastolic blood pressure, glucose, uric acid, fasting insulin, triglycerides and HDLC as metabolic syndrome variables. Results: The areas under the receiver operating characteristic (ROC) curves were 0.849 (95% CI: 0.780, 0.919) for BMI, 0.868 (95% CI: 0.801, 0.934) for waist circumference and 0.834 (95% CI: 0.757, 0.910) for the triceps/subscapular skinfolds ratio. No statistically significant differences were found for the three areas under the ROC curves. The point on the ROC curve closest to 1 corresponded to the 65th percentile for BMI, to the 70th percentile for waist, and to the 40th percentile for the triceps/subscapular skinfolds ratio. Conclusion: Waist circumference seems to be the best predictor of children with the metabolic syndrome in paediatric clinical settings.     

Waist circumference and waist-to-height ratio in Norwegian children 4-18 years of age: reference values and cut-off levels

Aim: To establish reference values for waist circumference and waist‐to‐height ratio of Norwegian children. Material: Data were collected in 2003–2006 as part of a cross‐sectional study, including 5725 children 4–18 years of age. Reference curves were fitted with the LMS method; appropriate cut‐offs were selected using receiver operating characteristic analysis. Results: Reference values for waist circumference and waist‐to‐height ratio are presented. Mean waist circumference increased with age for both genders. Boys had a higher waist circumference at almost all ages. Mean waist‐to‐height ratio decreased until early adolescence and thereafter increased slightly towards adult age. There was a strong positive correlation between waist circumference and BMI (r = 0.907, p < 0.01) and a moderate positive correlation between waist‐to‐height ratio and BMI (r = 0.397 p < 0.01). A waist circumference cut‐off value of 1.0 SDS (85th percentile) gave a sensitivity of 79% and a specificity of 94% to detect overweight. A cut‐off value of 1.6 SDS (95th percentile) gave a sensitivity of 94% and a specificity of 96% to detect obesity. Conclusion: This study presents the first reference values of waist circumference and waist‐to‐height ratio for Norwegian children 4–18 years, which also represent the first reference in Scandinavian schoolchildren. The 85th and 95th percentiles of waist circumference are proposed as appropriate cut‐offs for central overweight and obesity.     

German head circumference references for infants, children and adolescents in comparison with currently used national and international references

Aim: To present valid head circumference (HC) percentiles from early infancy to 18 years and to compare them with percentiles currently used in Germany by Prader, as well as to international WHO and CDC references. Methods: Nationally representative sample of 17,158 children and adolescents aged 0.25–17.98 years (KiGGS study 2003–2006) with standardized HC measurement. HC references were created using Cole’s LMS method. Results: The median growth of HC is largest in the first year of life. Adult HC is reached at age 16 years in girls, while in boys, HC growth continues through age 17 years and adult HC have to be derived from future KiGGS follow‐up examinations. KiGGS percentiles are quite similar from early infancy to early school age compared to older Prader references, but higher thereafter (maximum difference of median HC: girls 1.4 cm, boys 0.9 cm). KiGGS percentiles are also higher than WHO and CDC percentiles over most of the compared age range, but differences are less pronounced compared to Prader. Conclusion: The KiGGS HC references presented here for boys and girls aged 4 months through 17 years are more valid than currently used German references. Because of the similarity of KiGGS and the currently used reference by Prader in early infancy, the currently used Prader reference for 0–4 months could complement KiGGS to cover the entire age range from birth to the end of adolescence.     

First reference curves of waist circumference and waist-to-height ratio for Tunisian children

Abdominal obesity for childrenWaist circumference (WC) and waist-to-height ratio (WTHR) reference curves are used to assess the risk of cardiovascular disease in children. The aim of this study was to develop age- and sex-smoothed WC and WTHR reference curves for Tunisian children. Data were collected during the period 2014–2015 in a cross-sectional study including 2308 children aged 6–18 years. The percentiles of WC and WTHR were developed using the LMS method. The optimal percentiles, which are associated with the body mass index (BMI) according to International Obesity Task Force (IOTF) criteria to identify overweight/obesity and with the 0.5 boundary value of WTHR to estimate cardiovascular risk, were identified by ROC curves and the Youden index (j). The results show the smoothed percentiles of WC and WTHR reference curves for Tunisian children. A comparison of the 50th percentiles with other references showed different trends in WC values. The 75th percentiles of WC and WTHR are the optimal percentiles that correspond to both PBMI25 (the percentile linked to BMI ≥ 25) and the 0.5 boundary value. However, the 90th percentiles correspond to PBMI30 (the percentile linked to BMI ≥ 30) in boys and girls.ConclusionThe new WC and WTHR reference curves can be added to clinical tools to help specialists in pediatric and physical health to reduce cardiovascular risk in Tunisian children.     

Population-based waist circumference and waist-to-height ratio reference values in preschool children

Aim:  To establish new reference values for measurements of waist circumference and waist-to-height ratio in preschool children.
Methods:  A population-based, cross-sectional study of 4502 children aged 0–5 years derived from child health care in a Swedish county. Measurements of weight, height and waist circumference were recorded using a standardized procedure.
Results:  New reference values for waist circumference and waist-to-height ratio for preschool children are presented. Reference charts were constructed and are presented. Waist circumference increased with age (r = 0.80, p < 0.001). After adjustment to the individual height, expressed as waist-to-height ratio, there was an inverse correlation to age during the first 5 years of age (r = −0.87, p < 0.001).
Conclusion:  The new reference values for waist circumference and waist-to-height ratio for Swedish preschool children enable future identification of new risk populations for childhood obesity. For clinicians, new reference charts for these two variables are provided for practical use.     

Relationship between pediatric adiposity and cardiovascular risk factors in Saudi children and adolescents

BackgroundThe etiology of childhood obesity is growing at alarming rates in developed and developing countries. The aim of the present study was to investigate the prevalence of cardiovascular risk factors (hypertension, dyslipidemia, and hyperglycemia) in a sample of Saudi children and to assess their association with different measures of body adiposity.MethodsA cross-sectional study was conducted of 200 Saudi children, who were randomly selected from the pediatric clinics at King Abdulaziz University Hospital, Jeddah, Saudi Arabia. Anthropometric variables were measured for all study subjects. Fasting blood samples were collected for measurement of blood glucose, insulin, and lipid profile.ResultsAlmost half of the study population was overweight and one tenth was obese according to body mass index levels, irrespective of sex. The prevalence of central obesity was higher using the waist-height ratio as opposed to waist circumference and this was true for both sexes. Significantly higher means levels of glucose, insulin, and lipids (P < 0.0001 in all) were seen among overweight and obese children than their lean counterparts. All obesity measures in children were significantly associated with cardiovascular risk factors.ConclusionThe severity of overall and abdominal obesity in Saudi children is associated with a higher prevalence of cardiovascular risk factors, with the relationship strength varying by sex.     

Neck circumference and excess weight: proposal of cutoff points for Brazilian adolescents

ObjectiveTo indicate neck circumference (NC) cutoff points to identify excess weight at different stages of somatic maturation and evaluate the association between NC and body mass index (BMI).MethodsCross-sectional study with 1715 adolescents. BMI was classified according to the World Health Organization (WHO) criteria. Somatic maturation was obtained through the peak growth velocity (PGV). To define the cutoff points, curves of the receiver operating characteristic (ROC) model were constructed. The agreement between the anthropometric evaluation instruments was analyzed. The association between the variables was verified.ResultsOf the girls, 93 were in the pre-PGV stage, 266 in the PGV stage, and 481 in the post-PGV stage. Of the boys, 264 were in the pre-PGV stage, 334 in the PGV stage, and 277 in the post-PGV stage. For the pre-PGV group, the cutoff point was 28 cm for females and 29 cm for males; for the group during PGV, the cutoff points were 30 cm for females and 33 cm for males; in the post-PGV group the cutoff values were 32 cm in females and 35 cm in males. The prevalence of excess weight was higher in the pre-PGV stage in males and in the PGV stage in females. The correlation coefficients were higher in the pre-PGV and PGV stages.ConclusionThe cutoff points for NC found in this study showed good sensitivity and specificity to identify excess weight in Brazilian adolescents and can be used as a reference in epidemiological studies.     

Waist circumference is an independent predictor of insulin resistance in black and white youths

OBJECTIVES: We examined how well waist circumference (WC) reflects total and abdominal fat and whether WC predicts insulin resistance independent of body mass index (BMI) percentile in youths. STUDY DESIGN: Body composition was measured by dual-energy x-ray absorptiometry and abdominal adiposity by computed tomography. Insulin sensitivity was measured by the hyperinsulinemic-euglycemic clamp. RESULTS: Both BMI percentile and WC were significantly associated (P < .01) with total and abdominal fat and insulin sensitivity. WC remained a significant (P < .01) correlate of total and abdominal fat and insulin sensitivity after controlling for BMI percentile. By contrast, BMI percentile did not remain a significant correlate of visceral fat and markers of insulin resistance after controlling for WC. Without exception, WC explained a greater variance in abdominal fat and metabolic profiles than did BMI percentile. CONCLUSIONS: Our findings suggest that the prediction of health risks associated with obesity in youths is improved by the additional inclusion of WC measure to the BMI percentile. Such observations would reinforce the importance of including WC in the assessment of childhood obesity to identify those at increased metabolic risk due to excess abdominal fat.     

The relationship between sleep duration and obesity in Turkish children and adolescents

Aim: To determine the relationship between sleep duration and obesity in Turkish children and adolescents.
Methods: This study was conducted in Turkey with 5358 children aged 6 to 17 years. Height, weight, waist circumference (WC), mid-upper arm circumference (MUAC), triceps skinfold thickness were measured. Body mass index (BMI), arm fat area were calculated. Self-reported sleep duration by parents were obtained.
Results: As sleep duration increased, BMI, which was significantly higher in girls sleeping ≤8 h, decreased (p < 0.05). WC, MUAC, BMI were significantly higher in boys sleeping ≤8 h versus males sleeping ≥10 h. Boys sleeping ≤10 h in 6.0–17.0-years had significantly higher risk of overweight/obesity. In 6.0 to 17.0 years, the risk of overweight/obesity in boys sleeping 9–10 h, 8–9 h and ≤8 h were 1.86-, 1.74- and 2.06-times higher respectively, versus children sleeping ≥10 h (p < 0.05).
Conclusion: Sleep duration may be an important factor for obesity and providing ≥10 h of sleep is recommended as a prevention strategy for obesity.     

高血压儿童腰围发育曲线及其与高血压相关性的研究

目的 了解高血压儿童腰围发育曲线特点,探讨与儿童高血压相关的腰围正常值合理切点.方法 研究对象为安徽省北、中、南3个地市的8194名7～17岁汉族城乡中小学生,测量腰围与血压.以LMS( lambda-mu-sigma)法拟合腰围随年龄变化的百分位数曲线.建立Logistic回归模型,计算不同百分位数腰围学生发生高血压的OR值.结果 高血压男生的腰围发育曲线明显向上平行偏离总体男生标准曲线,而高血压女生腰围发育曲线在12岁前向上逐渐偏离总体女生标准曲线,之后逐渐回归.男生腰围上升至同年龄别第60百分位数、女生腰围上升至同年龄别第70百分位数时,高血压发生风险即开始显著增加,男生腰围p60～组、P70～组、P80～组和P90～组的OR值从1.88(95％CI:1.18 ～2.99)逐渐上升至4.87(95％CI:3.31 ～7.16),女生腰围P70～组、P80～组和P90～组的OR值从1.71 (95％CI:1.07～2.73)逐渐上升至3.32(95％ CI:2.16～5.09).结论 高血压男生和女生的腰围发育曲线轨迹明显不同.从第85百分位数向下适当降低儿童腰围正常值切点有利于儿童心血管疾病风险的预防.     

Vitamin D deficiency in children and adolescents with obesity: a meta-analysis

ObjectiveTo evaluate the prevalence of vitamin D deficiency in obese children and adolescents when compared to eutrophic controls.MethodsSystematic review with meta-analysis covering studies with patients aged 0–18 years old diagnosed with obesity and vitamin D deficiency and control group of eutrophic patients. The studies were retrieved in the PubMed, Embase, and LILACS databases in December 2019. The search used the terms “obesity” in combination with “pediatric population” and “vitamin D”.ResultsThrough the search 3155 articles were retrieved; and after analysis, 20 studies were selected according to the study objectives. A total of 24,600 children and adolescents were included. Through meta-analysis, the relative risk for the association between obesity and vitamin D deficiency in the pediatric population was 1.41 (95% CI: 1.26–1.59) (I² = 89%, p < 0.01).ConclusionChildren and adolescents with obesity have higher risk of vitamin D deficiency.     

Biacromical and biiliac length and chest circumference measurements of male Turkish adolescents according to biological maturation

Adolescence is a period which is characterized by rapid physical growth and development of secondary sex characteristics. Male adolescence begins at 11–12 years of age and lasts ∼5 years. During this interval, there is a growth spurt period which is observed any time between 11 and 16 years of age, lasting 2–3 years. Some authors claim that a male may have nearly 20–25% of his adult height and 50% of his adult weight during adolescence.^1–3 When evaluating the maturational aspects of adolescence, it is essential to consider bone age (BA) as well as chronological age (CA). Bone age is the mean CA at which the skeletal maturation is normally attained. It is influenced by genetic, endocrinological and nutritional factors.^4–6 An adolescent may not demonstrate the expected maturational steps if his BA is retarded. This report examines the relationship between CA, biological maturation and some anthropometrical measurements.     

Prevalence of overweight and obesity in 5- and 12-year-old Finnish children in 1986 and 2006

Objective: To investigate the prevalence and the trends of overweight and obesity in Finnish 5- and 12-year-old children in 1986 and 2006.
Design: Retrospective cross-sectional study.
Subjects and methods: Anthropometric data were collected retrospectively from health examinations in Tampere and in three rural municipalities. The size of the 5- and 12-year-old cohorts were 2108 in 1986 and 4013 in 2006, respectively. The body mass index (BMI) was calculated. Overweight and obesity was estimated using the International Obesity Task Force cutoff values (ISO BMI).
Results: The prevalence of overweight (ISO BMI >25) and obesity (ISO BMI >30) in 5-year-old boys in 2006 was 9.8% and 2.5% and in girls 17.7% and 2.5%, respectively. At the age of 12 years, the corresponding figures in boys were 23.6% and 4.7% and in girls 19.1% and 3.2%. Between 1986 and 2006, the prevalence of overweight in 12-year-old children had increased 1.8 fold in boys (p < 0.001) and 1.5 fold in girls (p = 0.008). Overweight was significantly more common in rural than in urban areas.
Conclusion: During the last 20 years the prevalence of overweight has markedly increased in 12-year-old Finnish children, but remained nearly unchanged in 5-year-old children.