Abdominal obesity in German adolescents defined by waist-to-height ratio and its association to elevated blood pressure: the KiGGS study

Prevalence and determinants of obesity and its association with upper gastrointestinal diseases in people aged 40-69 years in Yangzhong, southeast China

Several international epidemiological studies have established a link between obesity and upper gastrointestinal cancer (UGC), but Chinese evidence is limited. This study aimed to determine the prevalence of obesity, especially central obesity, while investigating its association with upper gastrointestinal diseases in the high-risk population of Yangzhong, a typical high-risk area for UGC in southeastern China. We conducted a cross-sectional study from November 2017 to June 2021 involving 6736 residents aged 40-69. Multivariate logistic regression was used to assess independent factors influencing overweight/obesity and central obesity. We also analyzed the relationship between obesity and upper gastrointestinal diseases using multinomial logistic regression. The prevalence of overweight, obesity, waist circumference (WC), waist-to-hip ratio (WHR), and waist-to-height ratio (WHtR)-central obesity were 40.6%, 12.0%, 49.9%, 79.4%, and 63.7%, respectively. Gender, age, smoking, tea consumption, sufficient vegetable, pickled food, spicy food, eating speed, physical activity, family history of cancer, and family history of common chronic disease were associated with overweight /obesity and central obesity. Besides, education and missing teeth were only associated with central obesity. General and central obesity were positively associated with UGC, while general obesity was negatively associated with UGC precancerous diseases. There were no significant associations between obesity and UGC precancerous lesions. Subgroup analyses showed that general and central obesity was positively associated with gastric cancer but not significantly associated with esophageal cancer. Obesity is negatively and positively associated with gastric and esophageal precancerous diseases, respectively. In conclusion, general and central obesity were at high levels in the target population in this study. Most included factors influenced overweight/obesity and central obesity simultaneously. Policymakers should urgently develop individualized measures to reduce local obesity levels according to obesity characteristics. Besides, obesity increases the risk of UGC but decreases the risk of UGC precancerous diseases, especially in the stomach. The effect of obesity on the precancerous diseases of the gastric and esophagus appears to be the opposite. No significant association between obesity and upper gastrointestinal precancerous lesions was found in the study. This finding still needs to be validated in cohort studies.

Waist-circumference-to-height-ratio had better longitudinal agreement with DEXA-measured fat mass than BMI in 7237 children

BACKGROUND

The absolute agreement of surrogate measures of adiposity with dual-energy X-ray absorptiometry (DEXA)-measured body composition was examined.

METHODS

Over a 15-year follow-up, 7237 (3667 females) nine-year-old children from the Avon Longitudinal Study of Parents and Children (ALSPAC) UK birth cohort were included. Total fat mass (FM) and trunk FM were serially measured with DEXA at ages 9, 11, 15, 17, and 24 years. BMI and waist circumference-to-height ratio (WHtR) were computed. Pearson's correlations, intraclass correlations (ICC), and area under curve (AUC) analyses were conducted.

RESULTS

Over 15 years, BMI, total FM, and trunk FM, increased but WHtR was relatively stable. WHtR provided a better longitudinal absolute agreement [males ICC 0.84 (95% CI 0.84-0.85); females 0.81 (0.80-0.82)] than BMI [(males (0.65 (0.64-0.66); females 0.72 (0.71-0.73)] with total FM as well as trunk FM from ages 9-24 years. WHtR cut-point for predicting excess total FM (75th-95th percentile) was 0.50-0.53 in males [AUC 0.86-0.94, sensitivity 0.51-0.79 and specificity 0.93-0.95]. WHtR cut-point for predicting excess total FM (75th-95th percentile) was 0.52-0.54 in females [AUC 0.83-0.95, sensitivity 0.38-0.68 and specificity 0.92-0.95]. Results were similar with trunk FM.

CONCLUSION

WHtR is an inexpensive alternative to BMI for predicting FM in pediatrics.

IMPACT

Waist circumference-to-height ratio (WHtR) is a better adiposity surrogate measure than body mass index (BMI) in predicting fat mass and discriminating lean mass from childhood through young adulthood. BMI has been used as an inexpensive surrogate measure of adiposity in children for several decades. However, emerging findings suggest that BMI fails to discriminate between fat mass adiposity and lean mass. This is the first-ever longitudinal study in over 7000 children followed up for 15 years that identified WHtR as an inexpensive accurate measure that discriminates fat mass from lean mass that could replace BMI measure of obesity in pediatrics.

Establishing international optimal cut-offs of waist-to-height ratio for predicting cardiometabolic risk in children and adolescents aged 6-18 years

BACKGROUND

Waist-to-height ratio (WHtR) has been proposed as a simple and effective screening tool for assessing central obesity and cardiometabolic risk in both adult and pediatric populations. However, evidence suggests that the use of a uniform WHtR cut-off of 0.50 may not be universally optimal for pediatric populations globally. We aimed to determine the optimal cut-offs of WHtR in children and adolescents with increased cardiometabolic risk across different countries worldwide.

METHODS

We used ten population-based cross-sectional data on 24,605 children and adolescents aged 6-18 years from Brazil, China, Greece, Iran, Italy, Korea, South Africa, Spain, the UK, and the USA for establishing optimal WHtR cut-offs. We performed an external independent test (9,619 children and adolescents aged 6-18 years who came from other six countries) to validate the optimal WHtR cut-offs based on the predicting performance for at least two or three cardiometabolic risk factors.

RESULTS

Based on receiver operator characteristic curve analyses of various WHtR cut-offs to discriminate those with ≥ 2 cardiometabolic risk factors, the relatively optimal percentile cut-offs of WHtR in the normal weight subsample population in each country did not always coincide with a single fixed percentile, but varied from the 75th to 95th percentiles across the ten countries. However, these relatively optimal percentile values tended to cluster irrespective of sex, metabolic syndrome (MetS) criteria used, and WC measurement position. In general, using ≥ 2 cardiometabolic risk factors as the predictive outcome, the relatively optimal WHtR cut-off was around 0.50 in European and the US youths but was lower, around 0.46, in Asian, African, and South American youths. Secondary analyses that directly tested WHtR values ranging from 0.42 to 0.56 at 0.01 increments largely confirmed the results of the main analyses. In addition, the proposed cut-offs of 0.50 and 0.46 for two specific pediatric populations, respectively, showed a good performance in predicting ≥ 2 or ≥ 3 cardiometabolic risk factors in external independent test populations from six countries (Brazil, China, Germany, Italy, Korea, and the USA).

CONCLUSIONS

The proposed international WHtR cut-offs are easy and useful to identify central obesity and cardiometabolic risk in children and adolescents globally, thus allowing international comparison across populations.

Flavonoid Intake From Cocoa-Based Products and Adiposity Parameters in Adolescents in Spain

Background

Cocoa-based products are a good source of flavonoids, which may have beneficial effects on metabolic health.

Objective

The aim of this study is to assess the relationship between flavonoids from cocoa-based products and adiposity parameters in adolescents.

Methods

A cross-sectional study was conducted involving 944 adolescents aged 11-14 years enrolled in the SI! Program for Secondary Schools trial in Spain with available baseline data from food frequency questionnaires and anthropometric measurements [weight, height, waist circumference (WC), and fat mass percentage (% FM) by bioimpedance analysis]. Fat mass index (FMI) and waist-to-height ratio (WHtR) were obtained by dividing fat mass by height and WC by height, respectively. Body mass index (BMI), WC, and FMI for age and gender z-score were calculated. Overweight/obesity was defined as BMI ≥ 85th percentile and excess adiposity as %FM or FMI ≥ 75th percentile. WC ≥ 90th percentile and WHtR with a 0.5 threshold were considered as criteria of abdominal obesity. Multilevel mixed-effect regressions were used to evaluate the association between flavonoids from cocoa-based products and adiposity parameters. Municipalities and schools were considered random effects.

Results

Participants with a higher flavonoid intake from cocoa-based products had lower WC z-score [B = -0.04, 95% CI (-0.07; -0.01), P-for trend = 0.045] and WHtR [B = -0.01, 95% CI (-0.02; -0.01), P- for trend < 0.001]. They also had lower probability of having abdominal obesity [OR 0.66, 95% CI (0.52; 0.85), P- for trend = 0.001]. Inverse associations were observed between flavonoids from cocoa powder and BMI z-score [B = -0.08, 95% CI (-0.12; -0.05), P < 0.001], WC z-score [B = -0.06, 95% CI (-0.11; -0.02), P = 0.003], WHtR [B = -0.01, 95% CI (-0.01; -0.00), P < 0.001], %FM [B = -1.11, 95% CI (-1.48; -0.75), P < 0.001], and FMI z-score [B = -0.18, 95% CI (-0.20; -0.17), P < 0.001]. Regarding dark chocolate, an inverse association only with WC z-score [B = -0.06, 95% CI (-0.08; -0.05), P < 0.001] was found. However, no association was observed between flavonoids from milk chocolate intake and anthropometric parameters.

Conclusions

A higher intake of flavonoids from cocoa-based products was associated with lower adiposity parameters and a lower probability of presenting abdominal obesity.

Diagnostic accuracy of anthropometric indices for discriminating elevated blood pressure in pediatric population: a systematic review and a meta-analysis

BACKGROUND

Childhood obesity is more likely to increase the chance of many adult health problems. Numerous studies have shown obese children to be more prone to elevated blood pressure (BP) and hypertension. It is important to identify an obesity anthropometric index with good discriminatory power for them in pediatric population.

METHODS

MEDLINE/PubMed, Web of Science, and Cochrane databases were retrieved comprehensively for eligible studies on childhood obesity and hypertension/elevated BP through June 2021. The systematic review and meta-analysis of studies used receiver operating characteristics (ROC) curves for evaluating the discriminatory power of body mass index (BMI), waist circumference (WC), and waist-to-height ratio (WHtR) in distinguishing children with elevated BP and hypertension.

RESULTS

21 cross-sectional studies involving 177,943 children and 3-19 years of age were included in our study. Meta-analysis showed that the pooled area under the reporting receiver-operating characteristic curves (AUC) and 95% confidence intervals (CIs) for BMI, WC, and WHtR to detect hypertension of boys were 0.68 (0.64, 0.72), 0.69 (0.64, 0.74), 0.67 (0.63, 0.71), for elevated BP, the pooled AUCs and 95% CIs were 0.67 (0.61, 0.73), 0.65 (0.58, 0.73), 0.65 (0.61, 0.71). The pooled AUCs and 95% CIs for BMI, WC and WHtR of predicting hypertension were 0.70 (0.66, 0.75), 0.69 (0.64, 0.75), 0.67 (0.63, 0.72) in girls, the pooled AUCs and 95% CIs of predicting elevated BP were 0.63 (0.61, 0.65), 0.62 (0.60, 0.65), 0.62 (0.60, 0.64) respectively. There was no anthropometric index was statistically superior in identifying hypertension and elevated BP, however, the accuracy of BMI predicting hypertension was significantly higher than elevated BP in girls (P < 0.05). The subgroup analysis for the comparison of BMI, WC and WHtR was performed, no significant difference in predicting hypertension and elevated BP in pediatric population.

CONCLUSIONS

This systematic review showed that no anthropometric index was superior in identifying hypertension and elevated BP in pediatric population. While compared with predicting elevated BP, all the indicators showed superiority in predicting hypertension in children, the difference was especially obvious in girls. A better anthropometric index should be explored to predict children's early blood pressure abnormalities.

Prevalence of Thinness, Overweight, Obesity, and Central Obesity in Finnish School-Aged Children: A Comparison of National and International Reference Values

INTRODUCTION

The global epidemic of obesity concerns children, and monitoring the prevalence is of highest priority. Body mass index (BMI) with age- and sex-specific cutoff values determines weight status in children, although multiple reference systems exist. Our aim was to compare the prevalence for thinness, normal weight, overweight, and obesity in Finnish school-aged children according to national and international reference values, as well as to determine which cutoff values for overweight agree with the criteria for central obesity.

METHODS

This study includes 10,646 children aged 9-12 years from the Finnish Health in Teens cohort. Height, weight, and waist circumference were measured in 2011-2014. BMI (weight [kg]/height [m]2) and the waist-to-height ratio (WHtR; waist [cm]/height [cm]) were calculated. The WHtR cutoff of >0.5 indicated central obesity. We compared the sex-specific prevalence of thinness, overweight, and obesity using the International Obesity Task Force (IOTF), World Health Organization (WHO) and Finnish (FIN) BMI-for-age reference values, as well as these three against central obesity based on the WHtR.

RESULTS

The prevalence of thinness, overweight, and obesity were 11.0%, 12.7%, and 2.6%, respectively, using IOTF; 2.6%, 15.9%, and 5.2% using WHO; and 5.1%, 11.4%, and 2.2% using FIN. Overweight and obesity were more common in boys than girls using WHO and FIN, while thinness was more common in girls using IOTF and FIN. IOTF versus WHO exhibited moderate agreement (κ = 0.59), which improved for IOTF versus FIN (κ = 0.74). Of those classified as overweight by WHO, 37% and 47% were regarded as normal weight according to IOTF and FIN, respectively. The prevalence of central obesity was 8.7%, and it was more common in boys than girls. WHO provided the highest sensitivity: 95% of individuals with central obesity were classified with overweight or obesity. Using FIN provided the highest specificity (93%).

CONCLUSION

Our findings show that WHO overestimates the prevalence of overweight and obesity, while IOTF overrates thinness. Thus, comparing prevalence rates between studies requires caution. The novelty of this study is the comparison of the cutoff values for overweight with central obesity. The choice of reference system affects the generalizability of the research results.

Thyroid Volume and Thyroid Function Parameters Are Independently Associated with Weight Status in Overweight Children

BACKGROUND

A relation between thyroid-stimulating hormone (TSH), insulin resistance - both of which are related to obesity - and thyroid volume has been suggested. Therefore, we analyzed thyroid volume and structure in relation to thyroid function parameters, weight status, and insulin resistance.

METHODS

This is a cross-sectional study in which weight status (BMI-SDS), thyroid function parameters (TSH, free tri-iodothyronine [fT3], and free thyroxine [fT4]), insulin resistance index (HOMA-IR), and thyroid volume (ultrasound) were determined in 617 overweight children (aged 10.4 ± 2.2 years, 50% male, BMI-SDS 2.5 ± 0.6) and in 27 normal-weight children of a similar age and gender. Furthermore, changes in thyroid volume and structure, and thyroid function parameters were analyzed in 83 obese children (51% male, mean age 10.3 ± 2.2) at baseline and at the end of a 1-year lifestyle intervention.

RESULTS

Overweight children had a significant greater thyroid volume (4.2 ± 1.8 vs. 4.1 ± 0.5 mL) and higher TSH (3.1 ± 1.5 vs. 2.4 ± 1.1 mU/L) and fT3 (4.4 ± 0.7 vs. 4.1 ± 0.5 pg/mL) concentrations compared to normal-weight children. In multiple linear regression analyses adjusted to multiple confounders, thyroid volume was significantly related to BMI-SDS (b coefficient 0.44 ± 0.10, r2 = 0.41) but not to any thyroid function parameter or HOMA-IR. Changes in BMI-SDS were significantly associated with changes in thyroid volume (r = 0.22). The changes in thyroid volume were not correlated to changes of any thyroid function parameter or HOMA-IR.

CONCLUSIONS

Thyroid volume is positively correlated to weight status in childhood obesity and the change is reversible after weight loss independently of thyroid function parameters and insulin resistance. Further studies are needed to understand why thyroid volume is increased reversibly in overweight children.

Body adiposity measures and risk of adolescent hypertension among the postpubescents Northeast India

OBJECTIVES

The present study attempts to associate and predict adolescent hypertension in Northeast India through body adiposity measures.

METHOD

A total of 728 adolescents aged 15 years and above were included in the present study after consent. Blood pressure and related anthropometric data were collected. The prevalence rate was calculated. Significant tests and correlation analyses were conducted between the blood pressure parameters and anthropometric body adiposity measures. The odds ratio (OR) was also calculated to assess the likelihood of risks. The receiver operating characteristic (ROC) curve analysis was performed to find the measured parameters' predictive cut-off values.

RESULTS

The prevalence of adolescent hypertension is 29.12%, and elevated blood pressure is 20.47%. Boys are more hypertensive than girls. Obese adolescents are more prone to hypertension. Overweight, obese, and abdominal volume index (AVI) has 2.31, 5.15, and 3.41 OR to develop hypertension significantly, irrespective of gender. Among the boys, waist circumference (WC), AVI, and waist to height ratio (WHtR) significantly correlate with hypertension at adjusted for age; they are better predictors with area under curve (AUC) value reach 0.7. Among the females, the BMI reaches AUC 0.7, making it a better assessment for hypertension.

CONCLUSION

The study highlights the concerns of adolescent hypertension among Northeast Indian adolescents, which needs attention. More studies in different regions must be conducted to understand the problem's crux to enable health policymakers to promote adolescent health.

Performance of waist-to-height ratio as a screening tool for identifying cardiometabolic risk in children: a meta-analysis

OBJECTIVE

To provide the latest evidence of performance and robustness of waist-to-height ratio (WHtR) in discriminating clusters of cardiometabolic risk factors (CMRs) and promote WHtR in routine primary health care practice in children, a meta-analysis was used.

METHODS

Searches was performed in eight databases from inception to July 03, 2020. Inclusion criteria were: (1) observational study, (2) children and adolescents, (3) provided WHtR measurements, (4) had CMRs as outcomes, and (5) diagnostic studies. Exclusion criteria were: (1) non-original articles, (2) unable to extract 2 × 2 contingency tables, (3) not in English or Chinese language, (4) populations comprising clinical patients, or (5) duplicate articles. WHtR cutoff points, 2 × 2 contingency tables were extracted from published reports. Outcomes included: CMR clusters of at least three CMRs (CMR₃), two (CMR₂), one (CMR₁), and CMR components. Bivariate mixed-effects models were performed to estimate the summarised area under the curves (AUSROC) with 95% CIs and related indexes. We conducted subgroup analyses by sex and East Asian ethnicity.

RESULTS

Fifty-three observational studies were included. The AUSROC reached 0.91 (95% CI: 0.88-0.93), 0.85 (95% CI: 0.81, 0.88) and 0.75 (95% CI: 0.71, 0.79) for CMR₃, CMR₂, and CMR₁, respectively. The pooled sensitivity and specificity for CMR₃ reached 0.84 and exceeded 0.75 for CMR₂. For CMR₁, the sensitivity achieved 0.55 with 0.84 for specificity. We had similar findings for our subgroup and sensitivity analyses.

CONCLUSIONS

WHtR shows good and robust performance in identifying CMRs clustering across racial populations, suggesting its promising utility in public health practice globally.

Prevalence and risk factor analysis for the nonalcoholic fatty liver disease in patients with type 2 diabetes mellitus

Although non-alcoholic fatty liver disease (NAFLD) is strongly associated with type 2 diabetes mellitus (T2DM), the diagnosis of NAFLD for T2DM patients remains a challenge.This study aimed to investigate the prevalence and risk factors for the NAFLD in T2DM outpatients.This is a retrospective, cross-sectional study that included 2405 T2DM patients treated and admitted for glucose control into the Endocrinology Department of our hospital from April 2017 to March 2019. Using strict exclusion criteria, the target patients were screened and divided into two groups: NAFLD patients (study group) and non-NAFLD patients (control group). Subsequently, 34 factors were compared between the two groups. Furthermore, multivariate analysis of the NAFLD risk factors was performed using logistic regression. Finally, the diagnostic significance of individual biochemical predictors, as well as the combined predictive indicator (CPI), for NAFLD was estimated using receiver operating characteristic (ROC) curve analysis.In this study, the overall prevalence of NAFLD in T2DM patients was 58.67%. Of the target patients, 17 factors were identified by univariate analysis to be associated with NAFLD, and 8 factors were found to be significant predictors for NAFLD using binary logistic regression modeling. Furthermore, the CPI and C-Peptide represent high diagnostic value for NAFLD in T2DM patients.This study provides a more comprehensive risk factor analysis for NAFLD in T2DM patients. These data can be used to provide timely diagnosis and effective management of NAFLD.

Nuchal Skinfold Thickness in Pediatric Brain Tumor Patients

BACKGROUND

Severe obesity and tumor relapse/progression have impact on long-term prognosis in pediatric brain tumor patients.

METHODS

In a cross-sectional study, we analyzed nuchal skinfold thickness (NST) on magnetic-resonance imaging (MRI) follow-up monitoring as a parameter for assessment of nuchal adipose tissue in 177 brain tumor patients (40 World Health Organization (WHO) grade 1-2 brain tumor; 31 grade 3-4 brain tumor; 106 craniopharyngioma), and 53 healthy controls. Furthermore, body mass index (BMI), waist-to-height ratio, caliper-measured skinfold thickness, and blood pressure were analyzed for association with NST.

RESULTS

Craniopharyngioma patients showed higher NST, BMI, waist-to-height ratio, and caliper-measured skinfold thickness when compared to other brain tumors and healthy controls. WHO grade 1-2 brain tumor patients were observed with higher BMI, waist circumference and triceps caliper-measured skinfold thickness when compared to WHO grade 3-4 brain tumor patients. NST correlated with BMI, waist-to-height ratio, and caliper-measured skinfold thickness. NST, BMI and waist-to-height ratio were associated with increased blood pressure. In craniopharyngioma patients with hypothalamic involvement/lesion or gross-total resection, rate and degree of obesity were increased.

CONCLUSIONS

NST could serve as a novel useful marker for regional nuchal adipose tissue. NST is highly associated with body mass and waist-to-height ratio, and easily measurable in routine MRI monitoring of brain tumor patients.

Comparisons of body mass index, waist circumference, waist-to-height ratio and a body shape index (ABSI) in predicting high blood pressure among Malaysian adolescents: a cross-sectional study

OBJECTIVE

To compare the performance of different anthropometric indices including body mass index (BMI), waist circumference (WC), waist-to-height ratio (WHtR) and a body shape index to predict high blood pressure (BP) in adolescents using the 90th and 95th percentiles as two different thresholds.

DESIGN

Cross-sectional study.

SETTING

Probability proportionate to size was used to randomly select two schools in Selangor state, Malaysia.

PARTICIPANTS

A total of 513 adolescents (58.9% women and 41.1% men) aged 12-16 years were recruited.

PRIMARY AND SECONDARY OUTCOME MEASURES

Weight, height, WC and BP of the adolescents were measured. The predictive power of anthropometric indices was analysed by sex using the receiver operating characteristic curve.

RESULTS

BMI and WHtR were the indices with higher areas under the curve (AUCs), yet the optimal cut-offs to predict high BP using the 95th percentile were higher than the threshold for overweight/obesity. Most indices showed poor sensitivity under the suggested cut-offs. In contrast, the optimal BMI and WHtR cut-offs to predict high BP using the 90th percentile were lower (men: BMI-for-age=0.79, WHtR=0.46; women: BMI-for-age=0.92, WHtR=0.45). BMI showed the highest AUC in both sexes but had poor sensitivity among women. WHtR presented good sensitivity and specificity in both sexes.

CONCLUSIONS

These findings suggested that WHtR might be a useful indicator for screening high blood pressure risk in the routine primary-level health services for adolescents. Future studies are warranted to involve a larger sample size to confirm these findings.

Associations between body mass index, waist circumference, waist-to-height ratio, and high blood pressure among adolescents: a cross-sectional study

The purpose of the present study was to examine the associations between body mass index (BMI), waist circumference (WC), waist-to-height ratio (WHtR), and high blood pressure (HBP), and to determine which anthropometric parameters can best predict HBP among Lithuanian adolescents aged 12–15 years. Data from the survey of “Prevalence and Risk Factors of HBP in 12–15-Year-Old Lithuanian Children and Adolescents (Study 1, 2010–2012)” were used; a total of 7,457 respondents (3,494 boys and 3,963 girls) were included in this analysis. Adolescents with BP above the 90th percentile were measured on two different occasions. Logistic regression analysis was used to assess the associations and to calculate odds ratios. Receiver operating characteristic (ROC) curve analysis was used to evaluate the predictive ability of the three anthropometric parameters to predict HBP. The adjusted odds ratios (aOR) in the highest quartiles of BMI, WC, and WHtR were statistically significant for both sexes separately (reference group – the first quartile): in boys, prehypertension – 4.91, 4.09, and 1.59; hypertension – 7.96, 6.44, and 2.81; and prehypertension/hypertension – 6.85, 5.65, and 2.37, respectively; and in girls, prehypertension – 3.42, 2.70, and 1.66; hypertension – 5.71, 3.54, and 2.90; and prehypertension/hypertension – 4.62, 3.17, and 2.31, respectively). According to the analyses of the ROC curve, BMI z-score provided the largest area under the curve (AUC) value, followed by WC z-score, while WHtR z-score showed the lowest AUC value in predicting elevated BP in both sexes separately. Among Lithuanian adolescents aged 12–15 years, both anthropometric indices – BMI and WC (but particularly BMI) – showed stronger associations with HBP and were better for the prediction of HBP, compared to WHtR.

Using height-corrected definition of metabolic syndrome in children and adolescents

Metabolic syndrome (MS) is common among children and adolescents. Age- and gender-specific references or age-, gender- and height-specific references were used in pediatric MS definitions. More recently, an increasing number of studies documented that the ratio of waist circumference (WC) to height (WHtR) and blood pressure to height (BPHR) were easy anthropometric indexes for detection of obesity and hypertension in children and adolescents. For these reasons, height-corrected MS definition was proposed. WHtR and BPHR were used as alternatives to WC and BP in the definition of MS. In the present review, we discuss the possibility of the height-corrected MS definition for identifying MS in children.

Secular change in waist circumference and waist-height ratio and optimal cutoff of waist-height ratio for abdominal obesity among Korean children and adolescents over 10 years

PURPOSE

This study aimed to evaluate the time trends of waist circumference (WC) and waist-height ratio (WHR), and to present WC and WHR distributions with optimal WHR cutoff for abdominal obesity in Korean children and adolescents.

METHODS

We performed a retrospective cross-sectional analysis of data from 13,257 children and adolescents (6,987 boys and 6,270 girls) aged 6-18 years who were included in the third to sixth Korea National Health and Nutrition Examination Survey (KNHANES, 2005-2015). Linear regression analyses were used to identify secular changes in WC and WHR by age, sex, and KNHANES waves. A receiver operating characteristic curve analysis was used to determine the optimal WHR cutoff values for abdominal obesity and cardiometabolic risk factors.

RESULTS

The mean WC and WHR distributions from 2005 to 2015 showed no significant secular changes between the KNHANES 4 waves (P for trend ≥0.05 in all ages and both sexes). The mean WCs in the present study were lower than those in the 2007 Korean National Growth Charts. The mean WHR at ages <13 years was statistically higher in the boys than in the girls, but did not significantly differ between the sexes among those aged 13 to 18 years. The optimal WHR cutoff for abdominal obesity was 0.48 (area under the curve, 0.985; 95% confidence interval, 0.985-0.985) in the 13- to 18-yearold adolescents.

CONCLUSION

WC and WHR showed no secular changes over 10 years. The optimal WHR cutoff for abdominal obesity of 0.48 is useful for diagnosing and managing obesity and thus preventing obesityrelated cardiometabolic complications in 13- to 18-year-old Korean adolescents.

Associations between general and central obesity and hypertension among children: The Childhood Obesity Study in China Mega-Cities

In this study, we examined the associations of general and central obesity and hypertension among Chinese children. Data was collected from 1626 children aged 7-16 years and their parents in four mega-cities across China. Mixed effect models examined associations of general and central obesity with hypertension, and between body mass index (BMI), waist circumference (WC), waist-to-height ratio (WHtR), systolic blood pressure (SBP) and diastolic blood pressure (DBP). The prevalence of general obesity, central obesity, and hypertension among the children was 11.1%, 19.7%, and 9.0%, respectively. More boys had general and central obesity than girls (15.2% vs. 6.9%; 27.4% vs. 11.7%, respectively; both P < 0.0001). Sex difference in hypertension rate was not statistically significant (9.3% in boys vs. 8.8% in girls, P = 0.7341). Both SBP and DBP were positively associated with BMI, WC, and WHtR, regardless of sex and region. General obesity (OR = 5.94, 95% confidence interval [CI]: 3.69-9.55) and central obesity (OR = 3.45, 95% CI: 2.27-5.23) were strongly associated with hypertension. The prevalence of general obesity, central obesity, and hypertension was high among Chinese children in the four mega-cities across China. Children's BMI, WC, and WHtR were positively associated with their SBP and DBP. Obese children were 3-6 times more likely to have hypertension.

Waist-to-height ratio is a useful index for nonalcoholic fatty liver disease in children and adolescents: a secondary data analysis

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is a global problem and pediatric obesity has risen dramatically. Early NAFLD might progress to nonalcoholic steatohepatitis (NASH) or liver cirrhosis and significantly increase liver disease-related mortality. We looked for NAFLD predictors in children and adolescents.

METHODS

This community-based, cross-sectional study ran from December 2012 to September 2013 in southwestern Taiwan. Children <10 and >19 years old, with detected hepatic diseases, or who drank alcohol were excluded. The diagnosis of NAFLD was based on ultrasound: age, sex, anthropometric measurements, and laboratory data were evaluated for associated risks by using logistic regression analysis. Receiver operating characteristic (ROC) curves were used to determine cutoff values.

RESULTS

We enrolled one thousand, two hundred and ten children (594 males; 616 females; mean age: 15.5 ± 2.8 years). Age, anthropometric measurements, and laboratory data were significantly higher in children with NAFLD. The association between NAFLD and the waist-to-height ratio (WHtR) was significant (adjusted odds ratio: 2.6; 95% confidence interval: 1.909-3.549; P < 0.001). It indicated highly suspicion of NAFLD (sensitivity: 70.1%; specificity 76.9%) when the WHtR for children and adolescents is above the cutoff value of 0.469.

CONCLUSIONS

The WHtR might be a powerful index of the severity of pediatric NAFLD.

Resting Heart Rate Percentiles and Associated Factors in Children and Adolescents

OBJECTIVES

To present population-based resting heart rate (RHR) percentiles and associated factors in children and adolescents.

STUDY DESIGN

Standardized RHR measurements with an oscillometric device were obtained from 3- to 17-year-olds who participated in the German Health Interview and Examination Survey for Children and Adolescents (n = 11 986). Age- and sex-specific RHR percentiles were derived using flexible age-dependent modeling. Linear regression was used to test associations of RHR and associated factors.

RESULTS

RHR decreased with age and mean RHR was on average 3.0 beats per minute (bpm) higher in girls than in boys (P < .01). The 95th RHR-KiGGS-percentile (P95) in boys and girls are up to 10 bpm lower than P95 based on pooled heterogeneous international studies and more similar to percentiles based on population data from NHANES (higher or lower by ≤5 bpm, depending on age). Factors independently associated with RHR in both sexes were age, SBP and height in children aged 3-10 years; and age, systolic blood pressure, and high aerobic fitness in adolescents aged 11-17 years. In girls, we further found an association between RHR and underweight (OR 3.3 and 4.7 for underweight girls aged 3-10 and 11-17, respectively, compared with normal weight girls). Associations between RHR and aerobic fitness, physical activity, and media use were stronger in boys than in girls.

CONCLUSION

This study provides population-based RHR percentiles and evidence for sex-dependent associations of cardiovascular risk factors with RHR in children and adolescents, many of which are lifestyle related.

Waist-to-height ratio, body mass index and waist circumference for screening paediatric cardio-metabolic risk factors: a meta-analysis

Waist-to-height ratio (WHtR) is superior to body mass index and waist circumference for measuring adult cardio-metabolic risk factors. However, there is no meta-analysis to evaluate its discriminatory power in children and adolescents. A meta-analysis was conducted using multiple databases, including Embase and Medline. Studies were included that utilized receiver-operating characteristics curve analysis and published area under the receiver-operating characteristics curves (AUC) for adiposity indicators with hyperglycaemia, elevated blood pressure, dyslipidemia, metabolic syndrome and other cardio-metabolic outcomes. Thirty-four studies met the inclusion criteria. AUC values were extracted and pooled using a random-effects model and were weighted using the inverse variance method. The mean AUC values for each index were greater than 0.6 for most outcomes including hypertension. The values were the highest when screening for metabolic syndrome (AUC > 0.8). WHtR did not have significantly better screening power than other two indexes in most outcomes, except for elevated triglycerides when compared with body mass index and high metabolic risk score when compared with waist circumference. Although not being superior in discriminatory power, WHtR is convenient in terms of measurement and interpretation, which is advantageous in practice and allows for the quick identification of children with cardio-metabolic risk factors at an early age.

Nuchal Skinfold Thickness: A Novel Parameter for Assessment of Body Composition in Childhood Craniopharyngioma

CONTEXT

Hypothalamic obesity, cardiovascular disease (CVD), and relapse/progression have a major impact on prognosis in childhood-onset craniopharyngioma (CP). We analyzed nuchal skinfold thickness (NST) on magnetic resonance imaging performed for follow-up monitoring as a novel parameter for body composition (BC) and CVD in CP.

OBJECTIVE

The objective of the study was to identify the association of NST with body mass index (BMI), waist to height ratio (WHtR), functional capacity, and blood pressure (BP) in CP and controls.

DESIGN

This was a cross-sectional and longitudinal prospective study in CP patients.

SETTING

The study was conducted at HIT-Endo, KRANIOPHARYNGEOM 2000/2007.

PATIENTS

Participants included 94 CP patients and 75 controls.

INTERVENTIONS

There were no interventions.

MAIN OUTCOME MEASURES

Association of NST with BC and BP in 43 CP and 43 controls was measured.

RESULTS

NST correlated with BMI SD score (SDS; r = 0.78; P < .001; n = 169) and WHtR (r = 0.85; P < .001; n = 86) in the total cohort and CP patients (NST-BMI SDS: r = 0.77, P < .001, n = 94); NST-WHtR: r = 0.835, P < .001, n=43) and controls (NST-BMI SDS: r = 0.792, P < .001, n = 75; NST-WHtR: r = 0.671, P < .001, n = 43). In CP, systolic BP correlated with NST (r = 0.575, P < .001), BMI SDS (r = 0.434, P = .004), and WHtR (r = 0.386, P = .011). Similar results were observed for diastolic BP in CP. In multivariate analyses, NST had a predictive value for hypertension in postpubertal CP and controls (odds ratio 6.98, 95% confidence interval [1.65, 29.5], P = .008). During a longitudinal follow-up, changes in NST correlated with changes in BMI SDS (P < .001) and WHtR (P = .01) but not with changes in BP and functional capacity.

CONCLUSIONS

Because monitoring of magnetic resonance imaging and BC is essential for follow-up in CP, NST could serve as a novel and clinically relevant parameter for longitudinal assessment of BC and CVD risk in CP.

Waist-to-height ratio as a screening tool for obesity and cardiometabolic risk

The waist-to-height ratio (WHtR), calculated by dividing the waist circumference (WC) by height, has recently gained attention as an anthropometric index for central adiposity. It is an easy-to-use and less age-dependent index to identify individuals with increased cardiometabolic risk. A WHtR cutoff of 0.5 can be used in different sex and ethnic groups and is generally accepted as a universal cutoff for central obesity in children (aged ≥6 years) and adults. However, the WHtR has not been validated in preschool children, and the routine use of WHtR in children under age 6 is not recommended. Prospective studies and meta-analysis in adults revealed that the WHtR is equivalent to or slightly better than WC and superior to body mass index (BMI) in predicting higher cardiometabolic risk. In children and adolescents, studies have shown that the WHtR is similar to both BMI and WC in identifying those at an increased cardiometabolic risk. Additional use of WHtR with BMI or WC may be helpful because WHtR considers both height and central obesity. WHtR may be preferred because of its simplicity and because it does not require sex- and age-dependent cutoffs; additionally, the simple message 'keep your WC to less than half your height' may be particularly useful. This review article summarizes recent publications on the usefulness of using WHtR especially when compared to BMI and WC as a screening tool for obesity and related cardiometabolic risks, and recommends the use of WHtR in clinical practice for obesity screening in children and adolescents.

The current prevalence and regional disparities in general and central obesity among children and adolescents in Shandong, China

BACKGROUND

Childhood obesity has increased dramatically during the past decades, both in developing and developed countries. The present study examined the prevalence and regional disparities in general and central obesity among children and adolescents in Shandong, China.

METHODS

A total of 30,459 students (15,249 boys and 15,210 girls) aged 7-18years participated in the study. Height, weight and waist circumference (WC) of all subjects were measured, body mass index (BMI) and waist-to-height ratio (WHtR) were calculated. The BMI cutoff points recommended by the International Obesity Task Force (IOTF) were used to define general obesity. Central obesity was defined as WHtR≥0.5. Both BMI and WHtR were used to define three types of obesity as follows: general obesity only, central obesity only and combined obesity.

RESULTS

The overall prevalences of general obesity only, central obesity only and combined obesity were 10.99, 8.47 and 8.70% for boys and 9.47, 5.12 and 3.19% for girls, respectively. The sum of the prevalence of the three types of obesity was 28.16% for boys and 17.78% for girls, boys had higher prevalence of obesity than girls (P<0.01). Substantial urban-rural and regional disparities exist in childhood obesity, children and adolescents from urban, coastal and high socioeconomic status (SES) districts showed a higher prevalence of obesity than their counterparts from rural, inland and low SES districts (P<0.01).

CONCLUSION

The widespread prevalence of obesity in children and adolescents has become an important public health concern. Results from this study also suggested that the additional measurement of WC (WHtR) is better than BMI alone to identify obese individuals, distinguishing the types of obesity and examining the prevalence of various types of obesity is useful in practice.

High-Intensity Interval Training for Overweight Adolescents: Program Acceptance of a Media Supported Intervention and Changes in Body Composition

High-intensity interval training (HIIT) consists of short intervals of exercise at high intensity intermitted by intervals of lower intensity and is associated with improvement of body composition and metabolic health in adults. Studies in overweight adolescents are scarce. We conducted a randomized controlled trial in overweight adolescents to compare acceptance and attendance of HIIT with or without weekly motivational encouragement through text messages and access to a study website. HIIT was offered for six months (including summer vacation) twice a week (60 min/session). Participation rates were continuously assessed and acceptance was measured. Clinical parameters were assessed at baseline and after six months. Twenty-eight adolescents participated in this study (age 15.5 ± 1.4; 54% female). The standard deviation score for body mass index over all participants was 2.33 at baseline and decreased by 0.026 (95% CI -0.048 to 0.10) units, p = 0.49. Waist to height ratio was 0.596 at baseline and decreased by 0.013 (95% CI 0.0025 to 0.024), p = 0.023. Participation within the first two months ranged from 65% to 75%, but fell to 15% within the last three months. Attendance in the intervention group was 14% (95% CI -8 to 37), p = 0.18, higher than the control group. Overall program content was rated as "good" by participants, although high drop-out rates were observed. Summer months constitute a serious problem regarding attendance. The use of media support has to be assessed further in appropriately powered trials.

Waist-to-Height Ratio as an Index for Cardiometabolic Risk in Adolescents: Results from the 1998-2008 KNHANES

PURPOSE

To describe the relationship between the waist-to-height ratio (WHtR) and cardiometabolic risk factors (CMRFs) and to evaluate the validity of WHtR in identifying adolescents with metabolic syndrome.

MATERIALS AND METHODS

We analyzed data from a pooled population of 4068 adolescents aged 10-19 years from the Korean National Health and Nutrition Examination Surveys conducted between 1998 and 2008. Overweight individuals were defined by body mass index (BMI) ≥85th percentile. Those with at least 2 CMRFs among hypertension, hyperglycemia, hypertriglyceridemia, and decreased high-density lipoprotein cholesterol (HDL-C) were classified as having multiple CMRFs.

RESULTS

WHtR was significantly related to systolic blood pressure, HDL-C, and triglycerides in both non-overweight and overweight adolescents (all p<0.01). Among overweight adolescents, the area under the curve (AUC) for WHtR in identifying multiple CMRFs was significantly greater than that for BMI (p=0.014). Metabolic syndrome was more common in overweight adolescents with a WHtR of ≥0.5 than in those with a WHtR of <0.5 (p<0.001). In non-overweight adolescents, the prevalences of multiple CMRFs (p=0.001) and metabolic syndrome (p<0.001) were higher in those with a WHtR of ≥0.5 than in those with a WHtR of <0.5. Among those without central obesity, the prevalence of multiple CMRFs was higher in those with a WHtR of ≥0.5 than in those with a WHtR of <0.5 (p=0.021).

CONCLUSION

WHtR is a simple and valid index for identifying adolescents with increased cardiometabolic risk and is related to CMRFs even in non-overweight adolescents. In adolescents already screened via BMI and waist circumference (WC), WHtR seems to be of additional help in discriminating those at higher cardiometabolic risk.

Waist-to-height ratio centiles by age and sex for Japanese children based on the 1978-1981 cross-sectional national survey data

OBJECTIVES

To construct waist-to-height ratio (WC/Ht) reference values and centile curves for Japanese children and to compare these references with those from other countries.

METHODS

The 1978-1981 national survey data were used for reference and the 1992-1994 national survey data were used for validation. The former included 19 233 children, and the latter included 10 446 children, aged 6 to 18 years. Waist circumferences (WC) were measured at the level of maximum waist narrowing in girls, and at the level of the top of the iliac crest in boys. Age- and sex-specific reference curves were fitted with the LMS method. Cut-off points were arbitrarily set at 85th, 90th, 95th and 97th centiles, and compared with WC/Ht 0.50.

RESULTS

The proportion of children in whom WC/Ht exceeded 0.50 was 18.7% of boys and 1.9% of girls, whereas the proportion of children exceeding 90th centile was 42.4% for boys and 17.3% for girls. The reference values decreased with age in girls but varied by age without a clear trend in boys.

CONCLUSIONS

The first reference values for WC/Ht are provided for Japanese youth based on the 1978-1981 national survey data. These curves are age- and sex-dependent, precluding the use of universal cut-off for WC/Ht of 0.50.

Waist:height ratio, waist circumference and metabolic syndrome abnormalities in Colombian schooled adolescents: a multivariate analysis considering located adiposity

Very few large studies in Latin America have evaluated the association between waist:height ratio (W-HtR) and cardiometabolic risk in children and adolescents. Further, multivariable analyses verifying the independence of located subcutaneous fat have not been conducted so far. The aim of this study was to evaluate the associations of W-HtR and waist circumference (WC) with metabolic syndrome abnormalities and high LDL-cholesterol levels in schooled adolescents before and after adjusting for trunk skinfolds and BMI. The sample consisted of 831 boys and 841 girls aged 10–17 years. Biochemical, blood pressure and anthropometrical variables were measured. Age- and sex-specific quartiles of W-HtR and WC were used in Poisson regression models to evaluate the associations. High WC values (highest quartilev. quartiles 1–3) were associated with high TAG levels in both sexes (prevalence ratio, boys: 2·57 (95 % CI 1·91, 3·44); girls: 1·92 (95 % CI 1·49, 2·47);P<0·05), and with high blood pressure specifically in female adolescents (3·07 (95 % CI 1·58, 5·98);P<0·05), independently of trunk skinfolds or BMI (P<0·05). Associations of high WC with high fasting glucose (boys), low HDL-cholesterol and having at least two abnormalities did not remain significant in most of the adjustments for trunk skinfolds or BMI (P>0·05). High W-HtR (highest quartilev. quartiles 1–3) was only independently associated with high TAG in female adolescents (1·99 (95 % CI 1·55, 2·56);P<0·05). In conclusion, WC showed better association with cardiometabolic risk than W-HtR in the children of this study. This observation does not support W-HtR as a relevant adiposity marker for cardiovascular and metabolic risk in adolescence.

Percentile Curves for Anthropometric Measures for Canadian Children and Youth

Body mass index (BMI) is commonly used to assess a child's weight status but it does not provide information about the distribution of body fat. Since the disease risks associated with obesity are related to the amount and distribution of body fat, measures that assess visceral or subcutaneous fat, such as waist circumference (WC), waist-to-height ratio (WHtR), or skinfolds thickness may be more suitable. The objective of this study was to develop percentile curves for BMI, WC, WHtR, and sum of 5 skinfolds (SF5) in a representative sample of Canadian children and youth. The analysis used data from 4115 children and adolescents between 6 and 19 years of age that participated in the Canadian Health Measures Survey Cycles 1 (2007/2009) and 2 (2009/2011). BMI, WC, WHtR, and SF5 were measured using standardized procedures. Age- and sex-specific centiles were calculated using the LMS method and the percentiles that intersect the adult cutpoints for BMI, WC, and WHtR at age 18 years were determined. Percentile curves for all measures showed an upward shift compared to curves from the pre-obesity epidemic era. The adult cutoffs for overweight and obesity corresponded to the 72nd and 91st percentile, respectively, for both sexes. The current study has presented for the first time percentile curves for BMI, WC, WHtR, and SF5 in a representative sample of Canadian children and youth. The percentile curves presented are meant to be descriptive rather than prescriptive as associations with cardiovascular disease markers or outcomes were not assessed.

Systematic review on the association of abdominal obesity in children and adolescents with cardio-metabolic risk factors

BACKGROUND

The adverse health effects of abdominal obesity are well documented in adults, but such association remains to be determined in the pediatric age group. This study aims to perform a systematic review on the association between abdominal obesity and cardio-metabolic factors such as dyslipidemia, hypertension, and hyperglycemia among children and adolescents.

MATERIALS AND METHODS

A systematic literature search was conducted using PubMed, Scopus and Google Scholar databases to May 2014. Two independent reviewers identified relevant papers in several steps. After studying the titles and texts of documents, repeated and irrelevant ones were excluded. The search was refined to the English language. We did not consider any time limitation. Studies with different measuring methods of abdominal obesity were included. Studies with abdominal obese patients secondary to other disease were excluded from the study. In final, the data of association of cardio-metabolic risk factors and abdominal obesity extracted from studies.

RESULTS

Overall, 3966 articles were reviewed, and 61 of them were studied according to the inclusion and exclusion criteria. Waist circumference (WC), waist-to-height ratio, and waist-to-hip ratio were the most common indexes used for defining abdominal obesity. The association of high blood pressure with increasing WC was seen in several studies. The association of other cardio-metabolic risk factors was seen in some studies.

CONCLUSION

Whatever the definition used for abdominal obesity and whatever the methods used for anthropometric measurements, central body fat deposition in children and adolescents increases the risk of cardio-metabolic risk factors. Therefore, more attention should be paid to abdominal obesity of children and adolescents both in clinical practice and in epidemiological studies.

Prevalence and risk factors of abdominal obesity in Polish rural children

Secular trends of body mass index (BMI) and waist circumference indicate greater increase in abdominal obesity compared to general obesity. Determinants of obesity described by BMI are relatively well documented in various populations, unlike abdominal obesity described by waist-to-height ratio (WHtR). The aim of the study was to determine prevalence and abdominal obesity (WHtR) risk factors in a cohort of 3048 rural children aged 7-12 years from southern Poland. Biological, socio-demographic and lifestyle factors were analysed, and odds ratio and 95% confidence interval were calculated using a logistic regression analysis. The prevalence of abdominal obesity in rural boys and girls in the sample was 11% and 9% respectively. Obesity in both parents, irregular breakfasts, irregular meals during the day and regularly consumed tea were significant factors of abdominal obesity risks in rural girls. Being the only child, low number of people in a household, obesity in both parents, high energy-dense food index and no exercise significantly increased the risk of abdominal obesity in rural boys. The study demonstrated tendencies similar to other European countries in the prevalence of abdominal obesity among sexes. Lifestyle behaviours should be changed and adapted to each sex since risk factors differ between the sexes and indicate higher eco-sensitivity in boys.

Blood pressure control rate and associated risk factors in hospitals of different grades in Chongqing, China

OBJECTIVE

The present article aimed to provide accurate estimate of the control rate of hypertension and the influencing factors in hospitals of different grades in Chongqing.

METHODS

In this survey, hypertensive outpatients were recruited from 5 tertiary hospitals, 6 secondary hospitals and 5 primary hospitals in 9 districts of Chongqing from November 2011 to May 2012. Outpatients were investigated by clinical interview with BP measurement and questionnaire. Univariate analyses and logistic regression analysis was used to assess the effect of variables on control of hypertension.

RESULT

A total of 2742 hypertensives were studied, of which 820 were from primary hospitals, 901 from secondary hospitals and 1021 from tertiary hospitals. The total control rate for hypertensive outpatients in Chongqing was 46.0%. The control rate of the primary,secondary and tertiary hospitals were 38.7%、46.7%、51.1%. Multinomial Logistic Regression showed that the control rate was positively correlated with mastery of knowledge of hypertension, normal BMI;whereas it was positively correlated with peasantry,the dissatisfactory with doctor's manner and the distrust to doctor.

CONCLUSION

Blood pressure control rate of hypertensive outpatients in Chongqing was low.High BMI, peasantry, lack of knowledge of hypertension, doctors' manners, distrust to doctor were the key reasons for low BP control rate.

Metabolic syndrome among children and adolescents from Southern Italy: contribution from the Calabrian Sierras Community Study (CSCS)

Among 1657 children and adolescents aged 6 to 14 years (787, 47% girls and 870, 53% boys) from primary and secondary schools in a 14-town Southern Italian community, HDL cholesterol (54 ± 15 mg/dl), triglycerides (61 ± 29 mg/dl), blood glucose (78 ± 10 mg/dl), systolic (101 ± 11 mm Hg) and diastolic (62 ± 10 mm Hg) blood pressures, waist circumference (WC) (66 ± 10 cm) and WC/height (0.46 ± 0.006) and triglycerides/HDL cholesterol (1.31 ± 0.99) ratios were measured. The distributions were similar in both genders. Age did not affect triglycerides/HDL cholesterol ratio, whereas there was a slightly positive correlation (p<0.00001) between WC/height and triglycerides/HDL cholesterol ratios. We present individual gender and age specific percentile distributions (as Supplementary materials). Using percentile cut-offs (≤ 10th for HDL cholesterol and ≥ 90th for the other components), there were 183 (11%) children or adolescents with low HDL cholesterol, 162 (9.77%) with high triglycerides, 178 (10.74%) with high blood glucose, 178 (10.74%) with high WC, 244 (20.76%) with high systolic or diastolic BP and 126 (7.6%) with high systolic and diastolic BP. Abnormally high BP was seen in 470 (28.36%) children or adolescents. Using abnormal percentile values of 3 of 5 of its components, metabolic syndrome (MS) was diagnosed in 70 (4.2%) subjects, similarly in both genders. To assess out-of-limit distributions of all 5 individual MS components in children and adolescents gender- and age-distributions derived from local epidemiological data should be used: these distributions are presented and they might now be used both for comparative and applicative purposes at least in Southern Europe.

Distribution curve of waist-to-height ratio and its association with blood pressure among children and adolescents: study in a large population in an eastern coastal province, China

Several studies have suggested that waist-to-height ratio (WHtR) is an accurate and easier index for evaluating abdominal obesity in both children and adults. The present study examined the distribution of WHtR and its association with blood pressure (BP) levels among children and adolescents in a large population in Shandong, China. A total of 38,810 students (19,453 boys and 19,357 girls) aged 7-17 years participated in this study. Height, waist circumference (WC), and BP of all subjects were measured, and WHtR was calculated. Abdominal obesity was defined as WHtR ≥0.5; high BP status was defined as systolic blood pressure (SBP) and/or diastolic blood pressure (DBP) ≥95th percentile for age and gender. Overall, 16.45% (95%CI: 15.93-16.97) and 7.80% (95%CI: 7.42-8.17) of boys and girls had a WHtR ≥0.5. WHtR was positively correlated with SBP and DBP in both boys and girls. The mean values of SBP and DBP for both boys and girls were all significantly higher in the WHtR ≥0.5 group than in the WHtR<0.5 group. Z-scores of BP and the prevalence of high BP increased with WHtR. The prevalence of high BP increased from 10.61 (boys) and 9.64% (girls) in the WHtR <0.34 group to 55.11 (boys) and 51.97% (girls) in the WHtR ≥0.58 group, an increase of 4.2- and 4.4-times. We conclude that children and adolescents with high WHtR might have an increased risk of elevated BP. These findings highlight the importance of the prevention of abdominal obesity in order to prevent future-related problems such as hypertension in children and adolescents.

Dietary, lifestyle and socio-economic correlates of overweight, obesity and central adiposity in Lebanese children and adolescents

The Eastern Mediterranean region is characterized by one of the highest burdens of paediatric obesity worldwide. This study aims at examining dietary, lifestyle, and socio-economic correlates of overweight, obesity, and abdominal adiposity amongst children and adolescents in Lebanon, a country of the Eastern Mediterranean basin. A nationally representative cross-sectional survey was conducted on 6-19-year-old subjects (n = 868). Socio-demographic, lifestyle, dietary, and anthropometric data (weight, height, waist circumference) were collected. Overweight and obesity were defined based on BMI z-scores. Elevated waist circumference (WC) and elevated waist to height ratio (WHtR) were used as indices of abdominal obesity. Of the study sample, 34.8% were overweight, 13.2% were obese, 14.0% had elevated WC, and 21.3% had elevated WHtR. Multivariate logistic regression analyses showed that male gender, maternal employment, residence in the capital Beirut, sedentarity, and higher consumption of fast food and sugar sweetened beverages were associated with increased risk of obesity, overweight, and abdominal adiposity, while regular breakfast consumption, higher intakes of milk/dairies and added fats/oils were amongst the factors associated with decreased risk. The study's findings call for culture-specific intervention strategies for the promotion of physical activity, healthy lifestyle, and dietary practices amongst Lebanese children and adolescents.

Prevalence of abdominal obesity in Spanish children and adolescents. Do we need waist circumference measurements in pediatric practice?

Background

Evidence indicates that central adiposity has increased to a higher degree than general adiposity in children and adolescents in recent decades. However, waist circumference is not a routine measurement in clinical practice.

Objective

This study aimed to determine the prevalence of abdominal obesity based on waist circumferences (WC) and waist to height ratio (WHtR) in Spanish children and adolescents aged 6 to 17 years. Further, the prevalence of abdominal obesity (AO) among normal and overweight individuals was analyzed.

Design

Data were obtained from a study conducted from 1998 to 2000 in a representative national sample of 1521 children and adolescents aged 6 to 17 years (50.0% female) in Spain. WC and WHtR measurements were obtained in addition to BMI. AO was defined as WHtR ≥0.50 (WHtR-AO), sex and age specific WC≥90^th percentile (WC-AO1), and sex and age specific WC cut-off values associated with high trunk fat measured by by dual-energy X-ray absorptiometry (WC-AO2).

Results

IOTF- based overweight and obsity prevalence was 21.5% and 6.6% in children and 17.4% and 5.2% in adolescents, respectively. Abdominal obesity (AO) was defined as WHtR≥0.50 (WHtR-AO), sex- and age-specific WC≥90th percentile (WC-AO1), and sex- and age-specific WC cut-off values associated with high trunk fat measured by dual-energy X-ray absorptiometry (WC-AO2). The respective prevalence of WHtR-AO, WC-AO1, and WC-AO2 was 21.3% (24.6% boys; 17.9% girls), 9.4% (9.1% boys; 9.7% girls), and 26.8% (30.6% boys;22.9% girls) in children and 14.3% (20.0% boys; 8.7% girls), 9.6% (9.8% boys; 9.5% girls), and 21.1% (28.8% boys; 13.7% girls) in adolescents.

Conclusion

The prevalence of AO in Spanish children and adolescents is of concern. The high proportion of AO observed in young patients who are normal weight or overweight indicates a need to include waist circumference measurements in routine clinical practice.