Waist-to-height ratio and cardiometabolic risk factors in adolescence: findings from a prospective birth cohort

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.

Glycemia and associated factors in a pediatric population in Mexico

Aims

In this study, we evaluated the association of sociodemographic, lifestyle and cardiometabolic factors with blood glucose levels in children and adolescents in Mexico.

Methods

An analytical cross-sectional study of 642 children and adolescents aged 6 to 19 years from different educational centers located in municipalities of the state of San Luis Potosí, Mexico, was carried out. Pearson χ2 and Spearman correlation tests and multiple linear regression models were used to evaluate the associations of the variables with glycemia.

Results

The prevalence of prediabetes was 8.0% in both sexes. Male participants were more likely to develop hyperglycemia than female participants (OR 2.7, 95% CI: 1.5-5.0). The variables associated with glucose levels were male sex, high socioeconomic status, inadequate diet, high blood pressure, and increased total cholesterol, LDL cholesterol, and triglycerides, which also explained up to 15.6% (p < 0.05) of the variability in glucose concentrations.

Conclusion

The detection of sociodemographic, lifestyle and cardiometabolic factors in children and adolescents will contribute to the implementation of prevention strategies for cardiometabolic diseases, among which prediabetes is common.

Malnutrition Patterns in Children with Chronic Kidney Disease

Malnutrition is frequent in children with chronic kidney disease (CKD). Apart from undernutrition and protein energy wasting (PEW), overnutrition prevalence is rising, resulting in fat mass accumulation. Sedentary behavior and unbalanced diet are the most important causal factors. Both underweight and obesity are linked to adverse outcomes regarding renal function, cardiometabolic risk and mortality rate. Muscle wasting is the cornerstone finding of PEW, preceding fat loss and may lead to fatigue, musculoskeletal decline and frailty. In addition, clinical data emphasize the growing occurrence of muscle mass and strength deficits in patients with fat mass accumulation, attributed to CKD-related wasting processes, reduced physical activity and possibly to obesity-induced inflammatory diseases, leading to sarcopenic obesity. Moreover, children with CKD are susceptible to abdominal obesity, resulting from high body fat distribution into the visceral abdomen compartment. Both sarcopenic and abdominal obesity are associated with increased cardiometabolic risk. This review analyzes the pathogenetic mechanisms, current trends and outcomes of malnutrition patterns in pediatric CKD. Moreover, it underlines the importance of body composition assessment for the nutritional evaluation and summarizes the advantages and limitations of the currently available techniques. Furthermore, it highlights the benefits of growth hormone therapy and physical activity on malnutrition management.

Waist-to-height-ratio is associated with sustained hypertension in children and adolescents with high office blood pressure

Background

Waist-to-height-ratio (WHtR) has been proposed as another indicator for cardiometabolic risk factors including hypertension. Normally, hypertension can be diagnosed in the office setting by detecting high blood pressure for three occasions. However, patients with high office blood pressure may not exhibit high blood pressure outside the office. Ambulatory blood pressure monitoring (ABPM) is a procedure to measure blood pressure over 24-h. Sustained hypertension is characterized as hypertension detected by both office measurement and ABPM. This study aimed to evaluate the performance of WHtR in the diagnosis of sustained hypertension in patients with high office blood pressure.

Materials and methods

Demographic data, height, body weight, body mass index (BMI), and waist circumference were retrospectively reviewed in children and adolescents who underwent ABPM due to persistently high office blood pressure. Patients were separated into two groups: a sustained hypertension group and a normal ABPM group. BMI was adjusted to z-score using the WHO Anthroplus software. WHtR was calculated by the formula: waist circumference (cm)/height (m). The performances of different parameters were analyzed using the receiver operating characteristic (ROC) curve and multivariate logistic regression.

Results

Sixty patients (63% male) with a mean age of 12.9 ± 3.7 years had persistently high office blood pressure. Twenty-nine (48.3%) had high ambulatory blood pressure parameters so-called "sustained hypertension." The sustained hypertension group had a higher mean BMI z-score (2.32 vs. 1.31, p = 0.01) and a higher mean WHtR (57.7 vs. 49.2 cm/m, p < 0.001) than those of the normal ABPM group. For the diagnosis of sustained hypertension, the ROC analysis revealed that WHtR had a greater area under the ROC curve (AUC) than that of BMI z-score (0.772 vs. 0.723). WHtR remained associated with sustained hypertension (OR 1.2, 95% CI 1.022-1.408, p = 0.026) after adjusting for age, gender, and BMI z-score.

Conclusions

Apart from being a more user-friendly metric, WHtR tended to outperform BMI z-score in predicting sustained hypertension in children and adolescents with persistently high office blood pressure.

Diagnostic test accuracy of waist-to-height ratio as a screening tool for cardiovascular risk in children and adolescents: a meta-analysis

CONTEXT

Waist-to-height ratio (WHtR) is a controversial evaluation index of cardiovascular risk factors (CVRFs) in children and adolescents.

OBJECTIVE

To assess the accuracy of WHtR as a measure to screen for clusters of at least one CVRF (CVRF₁), two CVRFs (CVRF₂), and three CVRFs (CVRF₃) in different ages, sexes, regions and cut-offs.

METHODS

The PubMed, Web of Science, EBSCOhost, Springer, Taylor & Francis Online, Wiley Online Library, Wanfang, and CNKI databases were searched for eligible publications up to June 2021. The QUADAS-2 checklist was used to assess the methodology of the included studies.

RESULTS

Twenty-two studies that evaluated 85281 children and adolescents aged 5-19 years were included in the meta-analysis. The AUSROC values were 0.56 (95% CI: 0.54-0.57), 0.82 (95% CI: 0.81-0.83), and 0.89 (95% CI: 0.89-0.90) for CVRF₁, CVRF₂, and CVRF₃, respectively. Higher AUSROC values were found for adolescents (12-19 years), that is, 0.91 (95% CI: 0.88-0.93), 0.90 (95% CI: 0.87-0.92) for males, and 0.91 (95% CI: 0.90-0.91) for a cut-off of ≥ 0.51 in the identification of CVRF₃.

CONCLUSION

WHtR can be used as an accurate screening tool for CVRF₃ and CVRF₂ in children and adolescents, and it is recommended to select different cut-offs according to different ages, sexes, and regions.

Diagnosis accuracy of waist-to-height ratio to predict cardiometabolic risk in children with obesity

BACKGROUND

Waist-to-height ratio (WHtR) predicts abdominal fat and cardiometabolic risk. In children with obesity, the most adequate cut-off to predict cardiometabolic risk as well as its ability to predict risk changes over time has not been tested. Our aim was to define an appropriate WHtR cut-off to predict cardiometabolic risk in children with obesity, and to analyze its ability to predict changes in cardiometabolic risk over time.

METHODS

This is an observational prospective study secondary to the OBEMAT2.0 trial. We included data from 218 participants (8-15 years) who attended baseline and final visits (12 months later). The main outcome measure was a cardiometabolic risk score derived from blood pressure, lipoproteins, and HOMA index of insulin resistance.

RESULTS

The optimal cut-off to predict the cardiometabolic risk score was WHtR ≥0.55 with an area under the curve of 0.675 (95% CI: 0.589-0.760) at baseline and 0.682 (95% CI: 0.585-0.779) at the final visit. Multivariate models for repeated measures showed that changes in cardiometabolic risk were significantly associated with changes in WHtR.

CONCLUSION

This study confirms the clinical utility of WHtR to predict changes in cardiometabolic risk over time in children with obesity. The most accurate cut-off to predict cardiometabolic risk in children with obesity was WHtR ≥0.55.

IMPACT

In children, there is no consensus on a unique WHtR cut-off to predict cardiometabolic risk. The present work provides sufficient evidence to support the use of the 0.55 boundary. We have a large sample of children with obesity, with whom we compared the previously proposed boundaries according to cardiometabolic risk, and we found the optimal WHtR cut-off to predict it. We also analyzed if a reduction in the WHtR was associated with an improvement in their cardiometabolic profile.

Accuracy of different cutoffs of the waist-to-height ratio as a screening tool for cardiometabolic risk in children and adolescents: A systematic review and meta-analysis of diagnostic test accuracy studies

The present systematic review with meta-analysis sought to estimate the accuracy of different waist-to-height ratio (WHtR) cutoff ranges as risk indicators for cardiometabolic health in different populations of children and adolescents. Systematic searches were undertaken to identify studies in apparently healthy participants aged 3-18 years that conducted receiver operating characteristic curve analysis and reported area under the receiver operating characteristic curves for WHtR with any cardiometabolic biomarker. Forty-one cross-sectional studies were included in the meta-analysis, including 138,561 young individuals (50% girls). Higher area under summary receiver operating characteristic (AUSROC) values were observed in cutoffs between 0.46 and 0.50 (AUSROC = 0.83, 95%CI: 0.80-0.86) and ≥0.51 (AUSROC = 0.87, 95%CI: 0.84-0.90) (p < 0.001 in comparison with cutoffs 0.41 to 0.45), with similar results in both sexes. The AUSROC value increased in the East and Southeast Asian regions using a WHtR cutoff of ≥0.46 (AUSROC = 0.90, 95%CI: 0.87 to 0.92). A cutoff of ≥0.54 was optimal for the Latin American region (AUSROC = 0.96, 95%CI: 0.94-0.97). Our meta-analysis identified optimal cutoff values of WHtR for use in children and adolescents from different regions. Despite the widely accepted WHtR cutoff of 0.50, the present study indicated that a single cutoff value of WHtR may be inappropriate.

Estimating trunk fat in children according to sex using basic somatic readings: an opportunity for improving evaluation among girls

BACKGROUND

The fat mass estimators waist-to-height ratio (WHtR) and relative fat mass-pediatric (RFMp) complement the widely accepted body mass index (BMI) in obesity evaluation.

AIMS OF THE STUDY

Conduct an easy appraisal of trunk fat and the cardiometabolic risk associated with pediatric obesity.

METHODS

A total of 472 children (39% boys in the total sample) were classified as underweight, normal weight, overweight or obese (nutritional groups, NGs) according to BMI Z-score after initial anthropometric data were obtained and ad hoc exclusion criteria were applied. WHtR and RFMp (% of total fat) were calculated for each group, associations were assessed through multiple linear regression (MLR), and differences between sexes were evaluated (medians, IQR).

RESULTS

The mean age (mean (95% CI)) was 10.8 y (10.1-11.1). The values in the total sample were as follows: WHtR, 0.5 (0.49-0.51) and RFMp%, 32.3 (31.7-33.0). In the overweight group, the values were as follows: WHtR, 0.51 (0.50-0.52) and RFMp(%), 34.2 (33.3-35.1). In the obese group, the values were as follows: WHtR, 0.56 (0.55-0.57) and RFMp(%), 37.8 (36.9-38.6). The associations were as follows (NG; independent variables): In the NG, adjusted R2 values were between 0.74 and 0.78. In the total sample, the beta coefficient was 3.36 (P < 0.001) for RFMp for girls; for waist circumference (WC), the beta coefficient was 2.97 (P < 0.001), and for WHtR the beta coefficients were - 0.01 (p < 0.001) and 0.03 (p < 0.001),for girls and for WC respectively. The sex differences were as follows: BMI exhibited no differences in the NG (Mann-Whitney U). WHtR (median (IQR)) differed (M vs. F) in the total sample (0.49 (0.45-0.54) vs. 0.52 (0.45-0.56), p < 0.004); in the overweight group (0.51 (0.48-0.53) vs. 0.54 (0.51-0.55), p < 0.001); and in the obese group (0.55 (0.52-0.57) vs. 0.57 (0.54-0.60), p < 0.004). RFMp (%) differed in the total group (29.21 (24.27-32.92) vs. 36.63 (30.2-39.51), p < 0.001); in the overweight group (31.24 (28.35-32.35) vs. 37.95 (35.75-38.82), p < 0.001) and in the obese group (35.89 (32.05-36.15) vs. 40.63 (38.27-42.42), p < 0.001).

CONCLUSIONS

WHtR and RFMp are simple and reliable indices that do not require centile charts. Their values, including waist circumference, can be used to estimate the different trunk fat components in boys and girls better than BMI, especially if individuals are overweight or obese. RFMp proved to be more reliable as it considers sex. Both should be included in routine anthropometric readings.

Screening for non-invasive risk factors of type 2 diabetes in overweight and obese schoolchildren

INTRODUCTION

The prevalence of type 2 diabetes mellitus (T2DM) is increasing among young people worldwide. The American Diabetes Association has defined the risk factors that are associated with this increased risk for developing T2DM in youths.

OBJECTIVE

To explore school children at high-risk for T2DM in Jordan.

MATERIALS AND METHODS

A descriptive cross-sectional study was conducted. The children were 10-14.9 years old. Weight, height, and waist circumference were measured, and the body mass index Z score (BMI) was determined. The waist to height ratio (WHtR) was calculated. Blood pressure was measured and three child́s risk factors were identified.

RESULTS

Eight hundred and seventy-one schoolchildren were screened; 26.0% were overweight and 19.3% were obese. The most common risk factor among overweight and obese children, accounting for 80.4%, was a positive family history of type 2 diabetes mellitus in first- or second-degree relatives. Children born to mothers with diabetes or gestational diabetes mellitus during the child's gestation represented 17.3%, and around 26.8% were found to have hypertension (stage 1 or 2). In relation to the risk factors, 12.6% presented no risk factors; 54.0% had at least one factor; 29.1% two risk factors and 4.3% had three risk factors.

CONCLUSION

Risk factors for T2DM are very common. Around 54% had one risk factor. Strategies aimed at reducing risk factors for T2DM, especially obesity, among Jordanian school children are urgently needed.

Impact of short-term change of adiposity on risk of high blood pressure in children: Results from a follow-up study in China

This study aimed to examine the impact of short-term adiposity change on risk of high blood pressure (HBP), and to assess the low limit range of body mass index (BMI) and waist-to-height ratio (WHtR) reduction proposed to decrease the HBP risk in children. Children were longitudinally surveyed at baseline and after a short-term follow-up. General obesity (GOB) is categorized by age and gender-specific BMI cut-off points, abdominal obesity (AOB) by WHtR. Logistic regression model was used to estimate relations between adiposity change and HBP risk with adjustment of covariates. A total of 28,288 children (median of baseline age:10 years) were involved with follow-up of 6.88±1.20 months. After the follow-up, 9.4% of the children had persistent general obesity (GOB), 2.8% converted from GOB to non-GOB, 0.9% had newly developed GOB. When compared with children remained non-GOB, children with continuous GOB status, newly developed GOB, converting from GOB to non-GOB had 5.03-fold (95%CI: 4.32~5.86), 3.35-fold (95%CI: 1.99~5.65), 2.72-fold (2.03~3.63) HBP risk, respectively. Similar findings were observed for abdominal obesity (AOB). Reduction of 0.21–0.88 kg/m² of baseline BMI (0.86–3.59%) or 0.009–0.024 of baseline WHtR (1.66–4.42%) in GOB or AOB children, respectively, was associated with significant decrease in HBP risk. Children with persistent obesity, newly developed obesity, or converting from obese to non-obese had significantly higher HBP risk. For children with GOB or AOB, reduction of <3.6% in BMI or <4.5% in WHtR could decrease the HBP risk.

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.

The Tri-ponderal Mass Index is associated with adiposity in adolescent type 2 diabetes mellitus: a cross-sectional analysis

Pediatric type 2 diabetes mellitus (T2DM) patients are often overweight or obese, yet there are no validated clinical measures of adiposity to stratify cardiometabolic risk in this population. The tri-ponderal mass index (TMI, kg/m³) has recently been reported as a measure of adiposity in children, but there has been no validation of the association of TMI with adiposity in pediatric T2DM. We hypothesized that in children with T2DM, the TMI can serve as a more accurate measure of adiposity when compared to BMI z-score, and that it is associated with components of the metabolic syndrome. This is a cross-sectional secondary data analysis from the Improving Renal Complications in Adolescents with Type 2 Diabetes Through REsearch (iCARE) study (n = 116, age 10.20–17.90 years). Spearman’s correlations and multivariable regression were used in the analyses. When compared to DXA, TMI demonstrated significant correlation with total adiposity versus BMI z-score (TMI r = 0.74, p-value < 0.0001; BMI z-score r = − 0.08, p-value 0.403). In regression analyses, TMI was associated with WHtR (B = 35.54, 95% CI 28.81, 42.27, p-value < 0.0001), MAP dipping (B = 1.73, 95% CI 0.12, 3.33, p-value = 0.035), and HDL (B = − 5.83, 95% CI − 10.13, − 1.54, p-value = 0.008). In conclusion, TMI is associated with adiposity and components of the metabolic syndrome in pediatric T2DM patients.

Screening for non-invasive risk factors of type 2 diabetes in overweight and obese schoolchildren

INTRODUCTION

The prevalence of type 2 diabetes mellitus (T2DM) is increasing among young people worldwide. The American Diabetes Association has defined the risk factors that are associated with this increased risk for developing T2DM in youths.

OBJECTIVE

To explore school children at high-risk for T2DM in Jordan.

MATERIALS AND METHODS

A descriptive cross-sectional study was conducted. The children were 10-14.9 years old. Weight, height, and waist circumference were measured, and the body mass index Z score (BMI) was determined. The waist to height ratio (WHtR) was calculated. Blood pressure was measured and three child́s risk factors were identified.

RESULTS

Eight hundred and seventy-one schoolchildren were screened; 26.0% were overweight and 19.3% were obese. The most common risk factor among overweight and obese children, accounting for 80.4%, was a positive family history of type 2 diabetes mellitus in first- or second-degree relatives. Children born to mothers with diabetes or gestational diabetes mellitus during the child's gestation represented 17.3%, and around 26.8% were found to have hypertension (stage 1 or 2). In relation to the risk factors, 12.6% presented no risk factors; 54.0% had at least one factor; 29.1% two risk factors and 4.3% had three risk factors.

CONCLUSION

Risk factors for T2DM are very common. Around 54% had one risk factor. Strategies aimed at reducing risk factors for T2DM, especially obesity, among Jordanian school children are urgently needed.

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.

The Genetic Architecture of the Clustering of Cardiometabolic Risk Factors: A Study of 8- to 17-Year-Old Chinese Twins

We explored the genetic architecture of metabolic risk factors of cardiovascular diseases (CVDs) and their clustering in Chinese boys and girls. Seven metabolic traits (body mass index [BMI], waist circumference [WC], systolic blood pressure [SBP], diastolic blood pressure [DBP], total cholesterol [TC], triglyceride [TG], and uric acid [UA]) were measured in a sample of 1016 twins between 8 and 17 years of age, recruited from the Qingdao Twin Registry. Cholesky, independent pathway, and common pathway models were used to identify the latent genetic structure behind the clustering of these metabolic traits. Genetic architecture of these metabolic traits was largely similar in boys and girls. The highest heritability was found for BMI (a2 = 0.63) in boys and TC (a2 = .69) in girls. Three heritable factors, adiposity (BMI and WC), blood pressure (SBP and DBP), and metabolite factors (TC, TG, and UA), which formed one higher-order latent phenotype, were identified. Latent genetic, common environmental, and unique environmental factors indirectly impacted the three factors through one single latent factor. Our results suggest that there is one latent factor influencing several metabolic traits, which are known risk factors of CVDs in young Chinese twins. Latent genetic, common environmental, and unique environmental factors indirectly imposed on them. These results inform strategies for gene pleiotropic discovery and intervening of CVD risk factors during childhood and adolescence.

Pediatric psoriasis and association with cardiovascular and metabolic comorbidities: Systematic review and meta-analysis

BACKGROUND/OBJECTIVES

There is an increasing volume of evidence which supports the link between psoriasis and cardiometabolic risk including obesity, metabolic syndrome, diabetes, hyperlipidemia, and myocardial infarction. Although one-third to one-half of psoriasis cases start during childhood, it is unclear whether childhood psoriasis is similarly associated with a cardiometabolic risk profile.

METHODS

Electronic database searches were performed to identify studies comparing the proportion of pediatric psoriasis cases with controls in terms of dichotomous outcomes including the proportion of patients with overweight BMI, obese BMI, metabolic syndrome, diabetes, hypertension, hyperlipidemia, ischemic heart disease, or heart failure; continuous outcomes recorded include BMI, systolic blood pressure, diastolic blood pressure, HDL, LDL, triglycerides, and total cholesterol.

RESULTS

A statistically significant association was found between pediatric psoriasis and overweight/obesity as well as waist:height ratio >0.5, in addition to metabolic syndrome, diabetes, hyperlipidemia, hypertension, and cardiac ischemia and failure. The association with obesity is dependent on the severity of disease, where moderate-severe psoriasis patients have higher odds of obesity compared to mild psoriasis.

CONCLUSIONS

Our systematic review and pooled meta-analysis demonstrate a significant association between childhood psoriasis and obesity, central adiposity, and other cardiometabolic comorbidities. Clinicians should consider the assessment of comorbidities in children with psoriasis, which may allow for early lifestyle interventions and education.

Waist-to-height ratio as a screening tool for cardiometabolic risk in children and adolescents: a nationwide cross-sectional study in China

OBJECTIVES

To demonstrate the accuracy and flexibility of using waist-to-height ratio (WHtR) as a screening tool for identifying children and adolescents with cardiometabolic risk (CMR) across a wide range of prevalence levels among general paediatric populations.

DESIGN

A nationwide population-based cross-sectional study with all data collected at school settings in six cities of China.

PARTICIPANTS

A total of 8130 children and adolescents aged 7-18 years with complete anthropometric and CMR measurements based on blood tests were recruited.

OUTCOME MEASURES

Elevated blood pressure, dyslipidaemia, elevated fasting blood glucose and central obesity were measured. The primary outcome, CMRs, was defined as meeting three or more of the above risk factors. The accuracy of WHtR for identifying CMRs was evaluated using areas under the curves (AUCs) with 95% CI of the receiver operating characteristic curve. The predictability of WHtR at given CMRs prevalence levels was estimated by positive predictive value (PPV) and negative predictive value.

RESULTS

Overall, 6.1% of study participants were presented with CMRs. WHtR had high AUCs ranging from 0.84 (95% CI 0.81 to 0.88) to 0.88 (95% CI 0.86 to 0.90) in the total population and age-subgroup and gender-subgroup. The overall optimal WHtR cut-off value was 0.467, with boys having a higher cut-off than girls (0.481 vs 0.456). WHtR achieved an overall sensitivity of 0.89 and PPV of 18.8% at a specificity of 0.75. The screening performance of WHtR remained satisfactory across a wide range of given CMRs prevalence levels (5%, 10% and 20%).

CONCLUSION

WHtR as a screening tool could accurately and flexibly identify children affected with the clusters of three or more of CMR factors from the general paediatric population with various CMR prevalence levels. Our findings provide support for policy-making on early CMR identification and management in the high-risk group of children.

Predictive Ability of Waist Circumference and Waist-to-Height Ratio for Cardiometabolic Risk Screening among Spanish Children

An excess of fat mass has been associated with adverse cardiometabolic risk factors. Different anthropometric measures have been proposed as alternative non-invasive measures for obesity-related cardiometabolic risk. To evaluate the magnitude of association between waist circumference (WC) and waist-to-height ratio (WtHR) with cardiometabolic risk factors and metabolic syndrome and to determine the WtHR cutoff associated with a more favorable cardiometabolic risk profile in Spanish children, data were taken from a cross-sectional survey conducted in 2010 among 848 schoolchildren aged 8–11 years from 20 public schools in the province of Cuenca (Spain). Anthropometric variables, glucose, insulin, triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), systolic (SBP) and diastolic blood pressure (DBP) and metabolic syndrome (MetS) were also analyzed. WtHR and WC had a good accuracy for TG, insulin, and MetS. The diagnostic odds ratio ranged from 2.95 to 9.07 for WtHR and from 5.30 to 27.40 for WC. The main result of the present study suggests that both WtHR and WC could be used as a screening tool to identify children with cardiometabolic abnormalities.

The utility of anthopometric indicators to identify cardiovascular risk factors in Vietnamese children

BMI, waist circumference (WC) and waist-to-height ratio (WHtR) can be used for discriminating children and adolescents at risk of CVD. However, consensus on how to use these anthropometric indicators is lacking for children and adolescents in Asia. Discrete criteria are promoted internationally, but continuous variables could be used. Data from a survey of 10 949 Vietnamese school-aged children (6-18 years) were used to evaluate the performance of anthropometric indicators to identify elevated blood pressure (BP), dyslipidaemia or at least three cardiovascular risk factors (CVRF). Weight, height, WC and BP were measured using standardised protocols; 1009 participants who had blood lipids were analysed. AUC was used to assess the performance, and the Youden index to identify optimal cut-offs. The prevalence of elevated BP, dyslipidaemia and CVRF was 26·5, 49·3 and 12·2 %, respectively. BMI, WC and WHtR had low capacity to identify elevated BP and dyslipidaemia (AUC range 0·61-0·66) but moderate capacity to identify CVRF (0·72-0·74). Optimal BMIZ cut-offs to identify elevated BP, dyslipidaemia and CVRF were 0·40, 1·01 and 1·1 sd; for WC z-score, they were 0·06, 0·49 and 0·62 sd; for WHtR, optimal cut-offs were close to 0·5. A BMIZ cut-off of 1·0 sd and a WHtR cut-off of 0·5 would, therefore, be useful criteria to identify Vietnamese children who are likely to have CVRF. However, further validation of these criteria in other studies of Asian children and adolescents is needed.

A simple cut-off for waist-to-height ratio (0·5) can act as an indicator for cardiometabolic risk: recent data from adults in the Health Survey for England

The National Institute for Health and Care Excellence (NICE) has acknowledged the value of waist-to-height ratio (WHtR) as an indicator for ‘early health risk’. We used recent UK data to explore whether classification based on WHtR identifies more adults at cardiometabolic risk than the ‘matrix’ based on BMI and waist circumference, currently used for screening. Data from the Health Survey for England (4112 adults aged 18+ years) were used to identify cardiometabolic risk, indicated by raised glycated Hb, dyslipidaemia and hypertension. HbA1c, total/HDL-cholesterol and systolic blood pressure (BP) were more strongly associated with WHtR than the ‘matrix’. In logistic regression models for HbA1c ≥ 48 mmol/mol, total/HDL-cholesterol > 4 and hypertension (BP > 140/90 mmHg or on medication), WHtR had a higher predictive value than the ‘matrix’. AUC was significantly greater for WHtR than the ‘matrix’ for raised HbA1c and hypertension. Of adults with raised HbA1c, 15 % would be judged as ‘no increased risk’ using the ‘matrix’ in contrast to 3 % using WHtR < 0·5. For hypertension, comparative values were 23 and 9 %, and for total/HDL-cholesterol > 4, 26 and 13 %. Nearly one-third of the ‘no increased risk’ group in the ‘matrix’ had WHtR ≥ 0·5 and hence could be underdiagnosed for cardiometabolic risk. WHtR has the potential to be a better indicator of cardiometabolic risks associated with central obesity than the current NICE ‘matrix’. The cut-off WHtR 0·5 in early screening translates to a simple message, ‘your waist should be less than half your height’, that allows individuals to be aware of their health risks.

Association of urinary polycyclic aromatic hydrocarbons and obesity in children aged 3-18: Canadian Health Measures Survey 2009-2015

Polycyclic aromatic hydrocarbons (PAHs) may contribute to obesity. Childhood obesity is a strong predictor of adult obesity and morbidity; however, the relationship between PAHs and obesity in young children (e.g., aged 3-5) has not been studied. We examined the association between urinary PAH metabolites and measures of obesity in children. We analyzed data from 3667 children aged 3-18 years who participated in the Canadian Health Measures Survey (CHMS, 2009-2015). We ran separate multivariable linear models to estimate the association between quartiles of PAH metabolites and each of body mass index (BMI) percentile, waist circumference (WC), and waist-to-height ratio (WHtR) in the total population, as well as in the age subgroups 3-5, 6-11, and 12-18, adjusting for age, sex, ethnicity, education, income quintile, diet, creatinine, and exposure to environmental tobacco smoke. A multinomial logistic regression model estimated adjusted odds ratios for risk of central obesity. BMI, WC, and WHtR were positively associated with total PAH and naphthalene metabolites in the total population aged 3-18 and in age groups 6-11 and 12-18. In 3-5 year olds, WHtR, but not BMI, was significantly associated with total PAH, naphthalene, and phenanthrene metabolites. Overall, those in the highest quartile for naphthalene or total PAH metabolites had three times greater odds of having central obesity compared with those in the lowest quartile. Urinary PAH metabolites are associated with WHtR, an indicator of central obesity and predictor of health risks associated with obesity, in children as young as 3-5.

Sex and area differences in the association between adiposity and lipid profile in Malawi

Background

Evidence from high-income countries shows that higher adiposity results in an adverse lipid profile, but it is unclear whether this association is similar in Sub-Saharan African (SSA) populations. This study aimed to assess the association between total and central adiposity measures and lipid profile in Malawi, exploring differences by sex and area of residence (rural/urban).

Methods

In this cross-sectional study, data from 12 096 rural and 12 847 urban Malawian residents were used. The associations of body mass index (BMI) and waist to hip ratio (WHR) with fasting lipids (total cholesterol (TC), low-density lipoprotein-cholesterol (LDL-C), high-density lipoprotein-cholesterol (HDL-C) and triglycerides (TG)) were assessed by area and sex.

Results

After adjusting for potential confounders, higher BMI and WHR were linearly associated with increased TC, LDL-C and TG and reduced HDL-C. BMI was more strongly related to fasting lipids than was WHR. The associations of adiposity with adverse lipid profile were stronger in rural compared with urban residents. For instance, one SD increase in BMI was associated with 0.23 mmol/L (95% CI 0.19 to 0.26) increase in TC in rural women and 0.13 mmol/L (95% CI 0.11 to 0.15) in urban women. Sex differences in the associations between adiposity and lipids were less evident.

Conclusions

The consistent associations observed of higher adiposity with adverse lipid profiles in men and women living in rural and urban areas of Malawi highlight the emerging adverse cardio-metabolic epidemic in this poor population. Our findings underline the potential utility of BMI in estimating cardiovascular risk and highlight the need for greater investment to understand the long-term health outcomes of obesity and adverse lipid profiles and the extent to which lifestyle changes and treatments effectively prevent and modify adverse cardio-metabolic outcomes.

Utility of waist circumference-to-height ratio as a screening tool for generalized and central obesity among Iranian children and adolescents: The CASPIAN-V study

BACKGROUND

Waist-to-height ratio (WHtR) is regarded as a simple anthropometric index for evaluating central adiposity because of its independence of age, gender, and ethnicity.

OBJECTIVE

The purpose of this study was to determine the optimal WHtR cutoff value in screening obesity and to compare it with other obesity indicators including body mass index (BMI) and waist circumference (WC) in Iranian children and adolescents.

METHODS

This large survey was conducted on 14 274 Iranian children and adolescents as a national school-based surveillance study (CASPIAN) in 2015. The receiver operating characteristic curve analysis was performed to estimate the optimal cut-off points of WHtR for the prediction of general and central obesity. The area under curve (AUC) was used to compare the ability of WHtR cut-off points, BMI and WC percentiles to discriminate students with and without obesity according to age and sex.

RESULTS

The optimal WHtR cutoff value for predicting general obesity was 0.49 and 0.48 for boys and girls, respectively and for central obesity according to WC ≥ 90th percentile was 0.50 for both genders. AUC values of WHtR for predicting general and central obesity were 87% and 96%, which indicates its strong predictive ability. For central obesity, the AUCs of WHtR were superior to those of WC percentiles. The kappa agreement coefficient was 0.55 between WC ≥ 90th percentile and WHtR ≥ 0.5.

CONCLUSIONS

The WHtR ≥ 0.5 as a simple and useful screening tool is better than WC, for predicting general and central obesity in different age and sex groups of Iranian children and adolescents.

Profiles of body mass index and blood pressure among young adults categorised by waist-to-height ratio cut-offs in Shandong, China

Background: Waist-to-height ratio (WHtR) is proposed as a valid measure of abdominal obesity and health risks in practice. The present study examined the profiles of weight status and blood pressure (BP) among young adults categorised by WHtR cut-offs.Methods: A total of 4226 college students (2107 males and 2119 females) aged 19-22 years participated in the study. The body mass index (BMI) cut-offs recommended by the Working Group on Obesity in China (WGOC) were used to define underweight, normal weight, overweight and obesity. The BMI and BP profiles within each WHtR category were examined.Results: For both males and females, 'the high WHtR group' (WHtR ≥ 0.5) had the highest, and 'the low WHtR group' (WHtR < 0.4) had the lowest BMI and BP levels. In the WHtR = 0.30-0.34 sub-group, 66.10% of males and 66.67% of females were underweight; in the WHtR ≥ 0.55 sub-group, 91.49% of males and 83.33% of females were obese; in the WHtR = 0.40-0.44 sub-group, 88.88% of males and 89.85% of females were normal weight. The prevalence of high BP in the WHtR < 0.5 group was 9.99% in males and 2.19% in females; the corresponding figures were 28.92% (males) and 14.06% (females) in the WHtR ≥ 0.5 group; the latter is significantly higher than the former (p < 0.01).Conclusion: Individuals with low WHtR were underweight and those with high WHtR were obese with high BP. Results from this study support WHtR as a simple and effective screening tool for abdominal obesity and high BP in practice.

Associations of cardiometabolic outcomes with indices of obesity in children aged 5 years and younger

BACKGROUND

Childhood obesity is a world-wide concern due to its growing prevalence and association with cardiometabolic risk factors in childhood and subsequent adult cardiovascular disease. In young pre-school children, there is uncertainty regarding which of the commonly used anthropometric measures of childhood obesity is best associated with cardiometabolic risk factors. This study compared the utility of common measures used in identifying obesity in these young children.

METHODS

The four commonly used metrics for identifying obesity in children: body fat percentage ≥ 90th percentile, waist circumference ≥ 90th percentile, BMI z score > 2 SD and waist-to-height ratio (WHtR) ≥ 0.5, were measured in a cohort of children born singleton, at full term and followed from birth (n = 761) to 5 years of age (n = 513). The utility of each in identifying cardiometabolic risk factors (fasting lipid profile, fasting blood glucose and blood pressure) was examined.

RESULTS

At age 5 years, children with percent body fat ≥ 90th percentile or waist circumference ≥ 90th percentile, were associated with higher levels of triglycerides, glucose, and systolic and diastolic blood pressures than those < 90th percentile, respectively. Such differences were not obvious at age 3 years or at birth. A BMI z-score > 2 SD was associated with higher levels of triglycerides and systolic and diastolic blood pressure but not glucose at age 5 years. Differences in HDL cholesterol, fasting glucose and systolic blood pressure were observed in children with BMI z score > 2 SD at age 3 years but not with the other indices of obesity. As almost all children had WHtR ≥ 0.5 at birth, ages 1 and 3 years, this measure could not differentiate increased cardiometabolic risk. At age 5 years, the differences were much more obvious, with significant differences in triglycerides and systolic and diastolic blood pressures between those with WHtR ≥ 0.5 and those with < 0.5.

CONCLUSION

Each of the four commonly used measures of childhood obesity shows moderate associations with cardiometabolic risk factors at 5 years, with no advantage of one measure over the other. These associations were less consistent at 3 years of age or younger. These observations have not been reported previously.

30-year cross-sectional trends in waist-to-height ratio in Australian school age children; 1985 to 2015

AIM

To report 30-year changes in the proportion of children with abdominal obesity measured by waist-to-height ratio (WHtR) ≥ 0.5.

METHODS

Secondary analysis of WHtR ≥ 0.5 data on Australian children age 7 to 15 years from five national cross-sectional population surveys conducted in 1985, 1995, 2007, 2012 and 2015. Changes in the proportions of children with a WHtR ≥ 0.5 across survey years, by age and sex were assessed using chi-squared tests.

RESULTS

Between 1985 and 2012, the proportion of children with WHtR ≥ 0.5 increased from 8.6% [95%CI: 8.0, 9.2] to 25.1% [95%CI: 23.5, 26.7]. An increase of ~5% each decade was observed between 1985 and 2007, and a 6.6% increase was observed between 2007 and 2012. Overall, there was a non-significant decrease in the proportion of children with WHtR ≥ 0.5 between 2012 (25.1% [95%CI: 23.5, 26.7] and 2015 (23.3% [95%CI: 21.6, 25.2].

CONCLUSION

Abdominal obesity has increased over the last 30 years in Australian children. In 2015, one in five children had WHtR ≥ 0.5, a marker of cardiometabolic risk in children. Our finding highlights the importance of including WHtR as a routine measurement in primary health care and population health surveys. This information is needed to guide policy and practice to manage long-term cardiovascular risk in children.

Alternative waist-to-height ratios associated with risk biomarkers in youth with diabetes: comparative models in the SEARCH for Diabetes in Youth Study

BACKGROUND/OBJECTIVES

The waist-to-height ratio (WHtR) estimates cardiometabolic risk in youth without need for growth charts by sex and age. Questions remain about whether waist circumference measured per protocol of the National Health and Nutrition Examination Survey (W_NHAHtR) or World Health Organization (W_WHOHtR) can better predict blood pressures and lipid parameters in youth.

PARTICIPANTS/METHODS

WHtR was measured under both anthropometric protocols among participants in the SEARCH Study, who were recently diagnosed with diabetes (ages 5-19 years; N = 2 773). Biomarkers were documented concurrently with baseline anthropometry and again ~7 years later (ages 10-30 years; N = 1 712). For prediction of continuous biomarker outcomes, baseline W_NHAHtR or W_WHOHtR entered semiparametric regression models employing restricted cubic splines. To predict binary biomarkers (high-risk group defined as the most adverse quartile) linear W_NHAHtR or W_WHOHtR terms entered logistic models. Model covariates included demographic characteristics, pertinent medication use, and (for prospective predictions) the follow-up time since baseline. We used measures of model fit, including the adjusted-R² and the area under the receiver operator curves (AUC) to compare W_NHAHtR and W_WHOHtR.

RESULTS

For the concurrent biomarkers, the proportion of variation in each outcome explained by full regression models ranged from 23 to 46%; for the prospective biomarkers, the proportions varied from 11 to 30%. Nonlinear relationships were recognized with the lipid outcomes, both at baseline and at follow-up. In full logistic models, the AUCs ranged from 0.75 (diastolic pressure) to 0.85 (systolic pressure) at baseline, and from 0.69 (triglycerides) to 0.78 (systolic pressure) at the prospective follow-up. To predict baseline elevations of the triglycerides/HDL cholesterol ratio, the AUC was 0.816 for W_WHOHtR compared with 0.810 for W_NHAHtR (p = 0.003), but otherwise comparisons between alternative WHtR protocols were not significantly different.

CONCLUSIONS

Among youth with recently diagnosed diabetes, measurements of WHtR by either waist circumference protocol similarly helped estimate current and prospective cardiometabolic risk biomarkers.

Utility of anthropometric indicators to screen for clustered cardiometabolic risk factors in children and adolescents

Background Anthropometric indicators are associated with cardiometabolic risk factors (CMRF), but there is no consensus as to which indicator is the most suitable to screen for clustered CMRF. This study aimed to evaluate the utility of five anthropometric indicators to screen for clustered CMRF in children and adolescents. Methods A cross-sectional study was conducted in 1139 schoolchildren aged 6-17 years from Northeastern Brazil. Body weight, height, waist circumference (WC) and subscapular (SSF) and triceps skinfold thickness (TSF) were measured. Body mass index (BMI) and waist-to-height ratio (WHtR) were calculated. The following CMRF were evaluated: elevated total cholesterol, low high-density lipoprotein-cholesterol (HDL-C), elevated low-density lipoprotein-cholesterol (LDL-C), high triglyceride concentration, hyperglycemia and high blood pressure. The participants were categorized into no CMRF, 1 CMRF, 2 CMRF and ≥3 CMRF. Receiver operating characteristic (ROC) curves were constructed to assess the accuracy of the anthropometric indicators in predicting CMRF for age group and sex. Results Poor associations were observed between the anthropometric indicators and 1 CMRF (accuracy of 0.49-0.64). The indicators showed moderate associations with 2 CMRF (accuracy of 0.57-0.75) and ≥3 CMRF (accuracy of 0.59-0.79). In general, TSF exhibited the worst performance in predicting CMRF, followed by WHtR. The highest accuracies were observed for BMI, WC and SSF, with no significant difference between these indicators. Conclusions The routine use of BMI, WC and SSF as epidemiological screening tools for clustered CMRF in childhood and adolescence should be encouraged.

Waist-to-height ratio as a risk marker for metabolic syndrome in childhood. A meta-analysis

BACKGROUND

Individuals with abdominal obesity have a higher cardiovascular risk, regardless of the degree of global overweight.

OBJECTIVE

To estimate the accuracy of the Waist/height ratio (WtHR) as a risk marker for metabolic syndrome (MS) in children or adolescents.

METHODS

Published cohort or cross-sectional studies (Pubmed, Embase-SCOPUS and CINAHL) were searched, with no limits of time. Studies providing Waist/height ratio and clustered criteria of metabolic syndrome were included.

RESULTS

Thirty-one studies (66,912 subjects) were selected. Overall, a high WtHR (≥0.5) was associated with a four-fold increased risk of clustered criteria of MS (odds ratio [OR] 4.15, 95% confidence interval [95% CI]: 2.69 to 6.42) and two-fold increased risk when adjusted by general obesity (adjusted OR 2.26, 95% CI: 1.29 to 3.98). The WtHR, as a quantitative measure, showed a pooled area under the curve of 0.76 (95% CI: 0.71 to 0.80) and, as a dichotomous measure, with a cut-off point close to 0.5, a sensitivity of 60% (95% CI: 50% to 68.8%) and a specificity of 79% (95% CI: 71.6% to 83.9%).

CONCLUSIONS

Measuring WtHR may be considered in regular health checks of children and adolescents, as it can measure cardiovascular risk regardless of the degree of general obesity.

Phthalate exposure as a risk factor for hypertension

Phthalates are ubiquitous in environment. Hypertension is a major risk factor for cardiovascular diseases. Phthalate exposure is associated with hypertension in multiple studies. This review aims to summarize the scientific literature on associations between phthalate exposure and hypertension and discuss the mechanisms in the relationship. We identified and reviewed original articles published to March 2018, using PubMed and Web of Science to search the terms "phthalate(s)," "phthalic acid," "blood pressure," "high blood pressure," "hypertension," "prehypertension," and "cardiovascular disease." Findings were summarized based on the relevance to the themes, including presentation of main phthalates and their major metabolites as well as associations of phthalate exposure with blood pressure in epidemiological and experimental studies. We identified ten population-based investigations and five toxicological experiments. Epidemiological data underscored a possible correlation between phthalate exposure and hypertension in adults, whereas individual study in children stands on the opposite. Experimental studies mainly targeted the increasing effect of phthalates on blood pressure. This review suggested some underlying mechanisms of phthalate-associated hypertension. Considering the current evidence, phthalate might be risk factors of hypertension. However, the effect of phthalate exposure in early life on blood pressure in later life or adulthood is still unclear. Well-designed longitudinal and molecular mechanism studies are indispensable.

Anthropometric features as predictors of atherogenic dyslipidemia and cardiovascular risk in a large population of school-aged children

BACKGROUND

Autopsy studies reveal that atherosclerosis lesions can be found as early as two years of age. To slow the development of this early pathology, obesity and dyslipidemia prevention should start from childhood making it urgent to explore new ways to evaluate dyslipidemia risk in children that can be applied widely, such as the non-invasive anthropometric evaluation.

OBJECTIVE

Assess the metabolic profile of a pediatric population at a specific age to describe the association between anthropometric and biochemical cardiovascular disease risk factors; and evaluate selected anthropometric variables as potential predictors for dyslipidemic cardiovascular risk.

DESIGN AND METHODS

Anthropometric features, bioimpedance parameters and fasting clinical profile were assessed in Lisbon and the Tagus Valley region pre-pubertal nine-year-old children (n = 1.496) from 2009-2013 in a descriptive, cross-sectional study. Anthropometric variables predictive power was evaluated through regression analysis.

RESULTS

At least one abnormal lipid parameter was found in 65% of "normal weight", 73% of "overweight" and 81% of "obese" children according to the International Obesity Task Force (IOTF) standards. Dyslipidemia was present in 67.8% of children. Waist-hip ratio (WHR) explained 0.4% of total cholesterol (TC) variance. Waist circumference (WC) explained 2.8% of apolipoprotein (APO) A1 variance. Waist-circumference-to-height-ratio (WHtR) explained 2.7%, 2.8% and 1.9% of low-density lipoprotein cholesterol (LDL-c), APO B, and N_HDL-c variance, respectively. Children with abnormally high WHR levels had an increase in risk of 4.49, 3.40 and 5.30 times, respectively, for developing cardiovascular disease risk factors measured as high-risk levels of TC, LDL-c and non-HDL-c (N_HDL-c) (p<0.05). Only 29.9% of "normal weight" children had no anthropometric, bioimpedance or biochemical parameters associated with CV risk.

CONCLUSION

A large proportion of school age children have at least one lipid profile abnormality. BMI, zBMI, calf circumference (CC), hip circumference (HC), WC, and WHR are directly associated with dyslipidemia, whereas HC and calf circumference (CC) adjusted to WC, and mid-upper arm circumference (MUAC), are all inversely associated with dyslipidemia. Selected anthropometric variables are likely to help predict increased odds of having CV risk factors.

Waist-to-height ratio remains an accurate and practical way of identifying cardiometabolic risks in children and adolescents

AIM

We evaluated how effectively the waist-to-height ratio (WHtR) identified cardiometabolic risk (CMR) in children and adolescents, compared with the tri-ponderal mass index, percentage of body fat and other obesity indexes.

METHODS

Eligible subjects were recruited from three metropolitan regions of China from May 2013 to June 2014. Subjects with at least three of the following abnormalities - hypertension, dyslipidemia, elevated fasting blood glucose and central obesity - were defined as CMR1 and children with at least two were defined as CMR2. The area under the curve (AUC) of the receiver operating characteristic curve was used to compare how effectively obesity indexes predicted CMR.

RESULTS

We recruited 3556 subjects aged 7-18 years. All five obesity indexes showed good, comparable performances in identifying CMR and the AUCs ranged from 0.89 to 0.90 for CMR1 and 0.83 to 0.85 for CMR2. The cut-off of 0.467 for WHtR achieved a sensitivity of 0.91 and specificity of 0.80 for predicting CMR1, with the best cut-offs being 0.463 for boys and 0.469 for girls.

CONCLUSION

The WHtR was a superior and practical screening tool for detecting CMR in this paediatric population, as it provided comparable accuracy to other methods and just required a simple calculation.

Analysis of different anthropometric indicators in the detection of high blood pressure in school adolescents: a cross-sectional study with 8295 adolescents

•

Overweight adolescents classified in any of three anthropometric indices have more HBP.

•

The sensitivity of the indicators was low and the specificity was high in detecting HBP.

•

Parents must be aware that high BMI, WC or WTHR are highly associated with HBP.

Background

High blood pressure is strongly associated with obesity in different populations. However, it is unclear whether different anthropometric indicators of obesity can satisfactorily predict high blood pressure in the school setting.

Objectives

This study evaluated the sensitivity and specificity of body mass index, waist circumference, and waist to height ratio in the detection of high blood pressure in adolescents.

Methods

The sample consisted of 8295 adolescents aged 10–17 years. Weight was measured using a digital scale, height with a stadiometer, and waist circumference using a tape measure. Blood pressure was measured by an automatic blood pressure measuring device. ROC curves were used for the analysis of sensitivity and specificity of the three anthropometric indices in identifying high blood pressure. Binary Logistic Regression was used to assess the association of body mass index, waist circumference, and waist to height ratio with high blood pressure.

Results

Low values of sensitivity were observed for body mass index (0.35), waist circumference (0.37), and waist to height ratio (0.31) and high values of specificity for body mass index (0.86), waist circumference (0.82), and waist to height ratio (0.83) in the detection of high blood pressure. An association was observed between adolescents classified with high body mass index (OR = 3.57 [95% CI = 3.10–4.10]), waist cirumference (OR = 3.24 [95% CI = 2.83–3.72]), and waist to height ratio (OR = 2.94 [95% CI = 2.54–3.40]) with high blood pressure.

Conclusions

Body mass index, waist circumference, and waist to height ratio presented low sensitivity to identify adolescents with high blood pressure. However, adolescents classified with high body mass index, waist circumference, and waist to height ratio demonstrated a high association of presenting high blood pressure.

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.

ANTHROPOMETRY AND CLUSTERED CARDIOMETABOLIC RISK FACTORS IN YOUNG PEOPLE: A SYSTEMATIC REVIEW

OBJECTIVE

To conduct a systematic review of the literature on the ability of anthropometric indicators to predict clustered cardiometabolic risk factors (CMRF) in children and adolescents.

DATA SOURCE

Studies published from June 1st, 2011 to May 31st, 2016 in the PubMed, SciELO and LILACS databases were analyzed. The research was based on keywords derived from the terms "anthropometric indicators" AND "cardiometabolic risk factors". Observational studies on the ability of anthropometric indicators as predictors of clustered CMRF in children and adolescents in Portuguese, English and Spanish languages were included. Studies with a specific group of obese patients or with other diseases were not included.

DATA SYNTHESIS

Of the 2,755 articles retrieved, 31 were selected for systematic review. Twenty-eight studies analyzed body mass index (BMI) as a predictor of clustered CMRF. Only 3 of the 25 cross-sectional studies found no association between anthropometric indicators and clustered CMRF. The results of six studies that compared the predictive ability of different anthropometric measures for clustered CMRF were divergent, and it was not possible to define a single indicator as the best predictor of clustered CMRF. Only six articles were cohort studies, and the findings suggested that changes in adiposity during childhood predict alterations in the clustered CMRF in adolescence.

CONCLUSIONS

BMI, waist circumference and waist-to-height ratio were predictors of clustered CMRF in childhood and adolescence and exhibited a similar predictive ability for these outcomes. These findings suggest anthropometric indicators as an interesting screening tool of clustered CMRF at early ages.

Prenatal Exposure to Perfluoroalkyl Substances and Cardiometabolic Risk in Children from the Spanish INMA Birth Cohort Study

BACKGROUND

Perfluoroalkyl substances (PFAS) may affect body mass index (BMI) and other components of cardiometabolic (CM) risk during childhood, but evidence is scarce and inconsistent.

OBJECTIVES

We estimated associations between prenatal PFAS exposures and outcomes relevant to cardiometabolic risk, including a composite CM-risk score.

METHODS

We measured perfluorohexanesulfonic acid (PFHxS), perfluorooctanesulfonic acid (PFOS), perfluorooctanoic acid (PFOA), and perfluorononanoic acid (PFNA) in maternal plasma (first trimester). We assessed weight gain from birth until 6 mo. At 4 and 7 y, we calculated the age- and sex-specific z-scores for BMI, waist circumference (WC), and blood pressure (BP) (n≈1,000). At age 4, we calculated the age-, sex-, and region-specific z-scores for cholesterol, triglycerides (TGs), high-density (HDL-C), and low-density lipoprotein cholesterol (LDL-C) (n=627). At age 4, we calculated a CM-risk score (n=386) as the sum of the individual age-, sex-, and region-specific z-scores for WC, BP, HDL-C, and TGs. We used the average between the negative of HDL-C z-score and TGs z-score to give similar weight to lipids and the other components in the score. A higher score indicates a higher cardiometabolic risk at age 4.

RESULTS

PFOS and PFOA were the most abundant PFAS (geometric mean: 5.80 and 2.32 ng/mL, respectively). In general, prenatal PFAS concentrations were not associated with individual outcomes or the combined CM-risk score. Exceptions were positive associations between prenatal PFHxS and TGs z-score [for a doubling of exposure, β=0.11; 95% confidence interval (CI): 0.01, 0.21], and between PFNA and the CM-risk score (β=0.60; 95% CI: 0.04, 1.16). There was not clear or consistent evidence of modification by sex.

CONCLUSIONS

We observed little or no evidence of associations between low prenatal PFAS exposures and outcomes related to cardiometabolic risk in a cohort of Spanish children followed from birth until 7 y. https://doi.org/10.1289/EHP1330.

Cardiometabolic risk profile based on body mass index in American Indian children and adolescents

BACKGROUND

Childhood obesity is associated with increased cardiometabolic risk.

OBJECTIVE

To study the relationship between body mass index (BMI) and cardiometabolic risk factors in American Indian children and adolescents.

METHODS

Differences in metabolic variables by age and sex-specific BMI percentiles (2000 Centers for Disease Control and Prevention Growth Charts) were examined in a cross-sectional analysis of 2977 individuals across three age categories. Children with an exam in two consecutive age categories were included in a longitudinal analysis. Spearman's correlations were used to test the association of BMI percentile with anthropometric and biochemical variables.

RESULTS

Body mass index percentile correlated with systolic (r = 0.24 to 0.38) and diastolic (r = 0.13 to 0.22) blood pressure, fasting plasma glucose (r = 0.20 to 0.33), 2-h plasma glucose (r = 0.30 to 0.46), total cholesterol (r = 0.12 to 0.23), serum triglycerides (r = 0.40 to 0.51) and HDL cholesterol (r = -0.36 to -0.43) in each age group (5-9, 10-13 and 14-17 years). Among participants examined in multiple age categories, BMI percentile increased over time. Change in BMI percentile from one age category to the next was associated with an increase in fasting glucose, 2-h glucose and triglycerides and a decrease in HDL cholesterol.

CONCLUSION

Higher BMI was associated with blood pressure elevation, hyperglycaemia and dyslipidaemia in American Indian children and adolescents.

Normal-weight obesity and cardiometabolic risk: A 7-year longitudinal study in girls from prepuberty to early adulthood

OBJECTIVE

To study whether normal-weight obesity in childhood is associated with increased cardiometabolic risk in early adulthood.

METHODS

This study assessed data for 236 girls followed from prepuberty to early adulthood. Growth chart data were obtained from birth to 18 years. Body composition was assessed by dual-energy x-ray absorptiometry and cardiometabolic risk by calculating continuous clustered risk score (at ages 11, 14, and 18). The association of body weight status with cardiometabolic risk from childhood to early adulthood was examined.

RESULTS

Subjects with normal-weight obesity were virtually indistinguishable from their normal-weight lean peers in terms of relative body weight and BMI but had significantly higher fat mass (7.1-7.3 kg) and cardiometabolic risk already in childhood, and this difference persisted into early adulthood (P <  0.001 for all).

CONCLUSIONS

Children and adolescents with normal body weight and high body fat percentage may be at increased risk for cardiometabolic morbidity in adulthood. Body fatness may be of utility in clinical practice to effectively identify children and adolescents at risk and to permit recommendation of lifestyle changes that could translate to lower risks of cardiovascular diseases in the future.

Self-reported physical activity using International Physical Activity Questionnaire in adolescents and young adults with visual impairment

BACKGROUND

Young people with visual impairment (VI) face many environmental barriers that influence physical activity.

OBJECTIVE

The aims of the study were to assess the level of physical activity (PA) in students with VI, with regard to their age, gender, level of VI, body mass index and abdominal obesity (AO), and to identify the percentage of study participants who did not meet the international recommendations for PA.

METHODS

Anthropometric measurements were taken to assess the body mass index and waist-to-height ratio. The PA level was measured by the International Physical Activity Questionnaire- Long Form. A sample of 122 students with VI aged 15.1-22.7 years were included in the study.

RESULTS

The mean total PA was 8514.5 ± 7201.0 Metabolic Equivalents min/week. Students with normal weight and excess weight had much greater total PA scores than those who were underweight (p < 0.05). Students with abdominal obesity had slightly lower total PA than those without AO. Blind students were engaged less in PA in most of the domains than partially-sighted students. Overall, 39.3% of participants did not meet the recommendation of 75 min/week of vigorous PA, and 23.8% did not meet the recommendation of almost 150 min/week of moderate PA. In total, 32.8% of participants did not meet the international recommendations of 420 min/week moderate or vigorous PA.

CONCLUSION

To improve the PA level of students with VI, health promotion initiatives focused on promoting PA during their school days and free time are required, based on innovative methods adjusted to their needs.

Utility of three anthropometric indices in assessing the cardiometabolic risk profile in children

OBJECTIVES

To evaluate the ability of BMI, WC, and WHtR to identify increased cardiometabolic risk in pre-adolescents.

METHODS

This is a cross-sectional study involving 192 children (10.92 ± 0.58 years, 56% female) from the United Kingdom between 2010 and 2013. Receiver operating characteristic curves determined the discriminatory ability of BMI, WC and WHtR to identify individuals with increased cardiometabolic risk (increased clustered triglycerides, HDL-cholesterol, systolic blood pressure, cardiorespiratory fitness, and glucose).

RESULTS

A WHtR ≥ 0.5 increased the odds by 5.2 (95% confidence interval 2.6 - 10.3) of having increased cardiometabolic risk. Similar associations were observed for BMI and WC. Both BMI-z and WHtR were fair predictors of increased cardiometabolic risk, although BMI-z demonstrated the best trade-off between sensitivity and specificity, 76.1% and 63.6%, compared with 68.1% and 65.5% for WHtR. Cross-validation analysis revealed that BMI-z and WHtR correctly classified 84% of individuals (kappa score = 0.671, 95% CI 0.55, 0.79). The sensitivity of the cut-points suggests that 89.3% of individuals were correctly classified as being at risk with only 10.7% misdiagnosed whereas the specificity of the cut-points indicated that 77.8% of individuals were correctly identified as being healthy with 22.2% of individuals incorrectly diagnosed as being at risk.

CONCLUSIONS

Findings suggest that WHtR provides similar cardiometabolic risk estimates to age and sex adjusted BMI.

Life course path analysis of total and central adiposity throughout adolescence on adult blood pressure and insulin resistance

BACKGROUND AND AIM

We aimed to study whether the effect of adolescent adiposity on adult blood pressure and insulin resistance was mediated by adult adiposity.

METHODS AND RESULTS

Data from the EPITeen cohort at 13, 17 and 21 years was used (n = 2211). Sex- and age-specific body mass index z-scores (BMIz) and waist-to-hip ratio (WHR) were used as indicators of total and central adiposity, respectively. Systolic blood pressure (SBP), glucose and insulin were assessed at 21 years and the homeostasis model assessment (HOMA-IR) was used as a marker of insulin resistance. Path analysis was applied to evaluate direct and indirect effects of adiposity (13, 17 and 21y) on adult SBP and HOMA-IR, separately for total and central adiposity and for each outcome. Results are presented as standardized regression coefficients [β (95%CI)]. The total effect of BMIz at 13 years on SBP at 21 years was 0.211 (0.178; 0.244), totally mediated by adult BMIz. Total effect of BMIz 13y on HOMA-IR was 0.248 (0.196; 0.299). Although this effect was mostly mediated by BMIz 21y, an additional direct effect from BMIz 17y was found [β = -0.240 (-0.315; -0.164)]. Central adiposity was also positively associated with SBP and HOMA-IR at 21 years, and the effect of adolescent WHR was totally mediated by adult WHR for both outcomes.

CONCLUSIONS

The effect of adolescent adiposity on adult SBP and HOMA-IR was mostly mediated by adult adiposity. However, for HOMA-IR an additional direct effect from total adiposity at 17 years was found.

Usefulness of the Waist Circumference-to-Height Ratio in Screening for Obesity and Metabolic Syndrome among Korean Children and Adolescents: Korea National Health and Nutrition Examination Survey, 2010-2014

The aims of this study were to assess the diagnostic value of the weight-to-height ratio (WHtR) for the detection of obesity and metabolic syndrome (MS) in Korean children and adolescents, and to determine the advantages of WHtR as a population-based screening tool in comparison with other obesity indicators, such as body mass index (BMI) and waist circumference (WC). We performed a cross-sectional analysis of data from 3057 children and adolescents (1625 boys, 1332 girls) aged 10-19 years who were included in the fifth Korean National Health and Nutrition Examination Survey (KNHANES, 2010-2012) up to the second year of the sixth KNHANES (2013-2014). Receiver operation characteristic (ROC) curves were generated to determine the optimal cutoff value and accuracy of WHtR for predicting individual obesity indicators or more than two non-WC components of MS. The area under the ROC curve (AUC) is a measure of the diagnostic power of a test. A perfect test will have an AUC of 1.0, and an AUC equal to 0.5 means that the test performs no better than chance. The optimal WHtR cutoff for the evaluation of general obesity and central obesity was 0.50 in boys and 0.47-0.48 in girls, and the AUC was 0.9. Regarding the assessment of each MS risk factor, the optimal WHtR cutoff was 0.43-0.50 in boys and 0.43-0.49 in girls, and these cutoffs were statistically significant only for the detection of high triglyceride and low High-density lipoprotein (HDL) cholesterol levels. When a pairwise comparison of the AUCs was conducted between WHtR and BMI/WC percentiles to quantify the differences in power for MS screening, the WHtR AUC values (boys, 0.691; girls, 0.684) were higher than those of other indices; however, these differences were not statistically significant (boys, p = 0.467; girls, p = 0.51). The WHtR cutoff value was 0.44 (sensitivity, 67.7%; specificity, 64.6%) for boys and 0.43 (sensitivity, 66.4%; specificity, 66.9%) for girls. There was no significant difference between the diagnostic power of WHtR and that of BMI/WC when screening for MS. Although the use of WHtR was not superior, WHtR is still useful as a screening tool for metabolic problems related to obesity because of its convenience.

Performance of different adiposity measures for predicting cardiovascular risk in adolescents

This study aims to compare the performance of body mass index (BMI), waist circumference (WC), and waist-to-height-ratio (WHtR) to predict the presence of at least 3 main CV risk factors in US adolescents. A total of 3621 adolescents (boys: 49.9%) aged 12–17 years from the US National Health and Nutrition Examination Survey (1999–2012) were included in this study. Measured CV risk factors included systolic/diastolic blood pressure, triglycerides, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and fasting plasma glucose. The AUC of BMI-z score, WC-z score and WHtR-z score to predict at least three CV risk factors were similar (~0.85), irrespective of criteria used to define abnormal levels of CV risk factors. A 1-SD increase in any of three indices to predict CV risk was also similar for the three adiposity scores. For instance, a 1-SD increase risk in BMI-z score, WC-z score and WHtR-z score was 3.32 (95%CI 2.53–4.36), 3.43 (95%CI 2.64–4.46), and 3.45 (95%CI 2.64–4.52), respectively, in the total population using the International Diabetes Federation definition. In addition, the most efficient WHtR cut-off for screening CV risk was ~0.50 in US adolescents. In summary, BMI, WC and WHtR performed similarly well to predict the presence of at least 3 main CV risk factors among US adolescents.

Blood pressure profiles of children and adolescents categorized by waist-to-height ratio cutoffs: study in a large sample in Shandong, China

BACKGROUND

Waist-to-height ratio (WHtR) is proposed as a simple and effective screening tool for abdominal obesity and cardiovascular disease risk factors. The present study examined the profiles of blood pressure (BP) among children and adolescents categorized by WHtR cutoffs.

PATIENTS AND METHODS

A total of 28 074 (14 015 boys and 14 059 girls) students aged 7-17 years participated in the study. Height, waist circumference and BP of all patients were measured, and WHtR was calculated. Relatively high blood pressure (RHBP) status was defined as systolic BP and/or diastolic BP of at least the 95th percentile for age and sex. All patients were divided into three groups (low, moderate and high) according to their WHtR. BP level and the prevalence of RHBP among the three groups were compared.

RESULTS

In both boys and girls, significant differences in BP level and the prevalence of RHBP were observed among the three groups (P<0.01). Children and adolescents aged 7-17 years in the 'high WHtR group' (≥0.5) had higher systolic BP and diastolic BP compared with those in the 'low WHtR group' (<0.4) by 6.07-11.49 and 3.28-6.34 mmHg for boys and 5.62-9.76 and 3.14-5.95 mmHg for girls; the 'high WHtR group' had the highest (34.02% for boys and 30.87% for girls) and the 'low WHtR group' had the lowest prevalence of RHBP (15.23% for boys and 12.53% for girls).

CONCLUSION

High WHtR is associated with elevated BP. These findings emphasize the importance of the prevention of abdominal obesity to prevent future problems such as hypertension in children and adolescents.

Low-Active Male Adolescents: A Dose Response to High-Intensity Interval Training

PURPOSE

High-intensity interval training (HIIT) is a potential alternative to traditionally recommended steady state exercise for providing health benefits in adolescents, yet its dose-response relationship in this cohort remains unclear, as does its translatability to real-world, nonclinical settings. The present study adopts a novel dose-response design to investigate the effects of undertaking 8 wk of HIIT on the cardiometabolic health of low-active male adolescents.

METHODS

Twenty-six male adolescents (age 16 ± 1 yr), identified as low active by nonparticipation in structured sport and physical education classes, were randomly assigned to one of five treatment groups. Corresponding with their group numbers (1-5), participants completed a number of HIIT "sets," which consisted of 4 repeated bouts of 20-s near-maximal exertion interspersed with 10-s passive recovery. Participants performed two HIIT sessions and one resistance training session each week for 8 wk. Baseline and follow-up health measures consisted of peak oxygen uptake (V˙O2peak) with an incremental ramp test to volitional exhaustion; body composition (including visceral fat mass, body fat, and lean tissue mass) with dual-energy x-ray absorptiometry; and lipid profile, glucose, insulin, and interleukin-6 from blood analysis. All health outcomes were analyzed as percentage changes, and data were modeled using a quadratic function to explore dose-response relationships.

RESULTS

Significant improvements were observed for V˙O2peak (∼6%), body fat percentage (∼4%), visceral fat mass (∼10%), and waist circumference-to-height ratio (∼3%), but there was no clear effect of dose across groups.

CONCLUSIONS

Low-active adolescent males performing a single HIIT set twice weekly, in addition to one resistance training session, gained meaningful improvements in fitness and body composition. Performing additional HIIT sets provided no additional improvements to those of the lowest dose in this study.

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.

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.

Prevalence of normal weight central obesity among Thai healthcare providers and their association with CVD risk: a cross-sectional study

This study aims to determine the prevalence of health personnel with normal weight central obesity and to investigate whether this group had higher cardiovascular disease (CVD) risk factors than those of the people with normal weight and without central obesity. A waist-to-height ratio was calculated as waist circumference (at umbilical level) in cm divided by height in cm. The central obesity cut-off level was 0.5. The body mass index was calculated as weight in kg divided by height in meters squared. The obesity cut-off level was 25 kg/m2. The prevalence of health personnel with normal weight central obesity was 15.4% (499 out of 3235). When compare this group to 1787 health personnel who had normal weight and without central obesity, they were 2.03 times (95% CI of adjusted OR; 1.62 to 2.54) more likely to have at least one CVD factor. The waist-to-height ratio cut-off value of 0.5 can be used as a self-assessment tool for central obesity without the need for a standard measuring tape. It is feasible to be implemented in screening or self-monitoring for the general population.