Validity of anthropometric indices in predicting high blood pressure risk factors in Iranian children and adolescents: CASPIAN-V study

Prediction of blood pressure based on anthropometric measurements in adolescents

BACKGROUND

Recently, an important health issue in children is obesity, leading to hypertension. The aim of this study was to determine association of blood pressure with anthropometric variables in adolescents.

METHODS

In this study, 1992 adolescents aged 11-18 years old between 2000 and 2007 were included. Cut point of anthropometric indices of waist circumference (WC), waist-to-stature ratio (WSR) and body mass index (BMI) was identified using Youden's index.

RESULTS

Cut point of BMI for identification of hypertension was 19.69, 25.5, 20.65 and 24.13 for boys at middle and high school, girls at middle and high school, respectively. This measure for WSR was 0.44, 0.50, 0.45 and 0.517 for boys at middle and high school, girls at middle and high school, respectively. Regarding WC, it was 69.50, 96.5, 65.5 and 77.5 for boys at middle and high school, girls at middle and high school, respectively.

CONCLUSIONS

In middle school boys, WSR, WC and BMI are associated with DBP but by increasing age, only BMI and weight are associated with DBP. BMI is the consistent anthropometric determinant of DBP. We also observed the relationship between WSR and SBP in boys, which could be applied as a predictive measure.

Assessment of the Performance of Obesity Measures in the Screening of Hypertension in a South African Adolescent Population

Obesity is known to be one of the most significant risk factors for essential hypertension in childhood. However, whether obesity cut-offs may predict hypertension screening in adolescents remains controversial. This study investigated the performance of obesity cut-off values for the screening of hypertension in a South African adolescent population. In this cross-sectional study, 1144 adolescents aged between 11 and 17 years were recruited from the Eastern Cape Province of South Africa. Anthropometric and blood pressure (BP) parameters including diastolic blood pressure (DBP), systolic blood pressure (SBP), and heart rate (HR) were measured. Assessment of the sensitivity and specific of obesity cut-off values in predicting hypertension was performed using receiver operating characteristic (ROC) analysis. Obesity was positively associated (p < 0.01) with hypertension. Obese individuals, based on the predicted obesity using BMI percentile cut-off (pBMI85.2%), were more likely to develop hypertension (odds ratio: 2.070; p < 0.001) than their counterparts based on the observed obesity cut-off (pBMI95%) (Odd ratio: 1.748 p = 0.004). The area under the curve (AUC) of BMI percentile and WHtR for screening SBP percentile, and DBP percentile and HR as per ROC analysis, was low (<0.65). Equally, the sensitivity and specificity were low (<0.6) for all BP measures (SBP, DBP, and HR). Furthermore, the cut-off values for blood pressure measures, as established by ROC analysis using anthropometric measures, were far below the recommended cut-off values for hypertension screening. The obesity cut-offs for BMI percentile and WHtR established in this populations showed poor performance in diagnosing hypertension even though they were strong predictors of hypertension.

Effectiveness of a body shape index in predicting pediatric high blood pressure

BACKGROUND

A body shape index (ABSI) is an emerging anthropometric indicator, challenging two traditional parameters: body mass index (BMI) and waist circumference (WC). We aimed to systematically compare and validate the capability of anthropometric indicators for determining pediatric high blood pressure (HBP).

METHODS

A total of 3150 participants aged 7-17 years were enrolled from Suzhou, China. Areas under the receiver operating characteristic curve (AUC) were obtained to evaluate the performance of anthropometric indicators in detecting HBP. DeLong's test was used to examine whether the AUCs of anthropometric indicators in contrast to BMI or original ABSI were statistically different. Furthermore, a meta-analysis was performed to combine results from this study and five similar articles from databases.

RESULTS

In Suzhou population, BMI exhibited the largest AUC (AUC = 0.705), followed by WC (AUC = 0.669) and original ABSI (AUC = 0.514). Modified ABSI (AUC: 0.537-0.681), although had slightly better performance than original ABSI, was still less valuable than BMI (P &lt; 0.05), either in the total sample or in boys. The meta-analysis with 21108 children and adolescents subsequently confirms the results derived from Suzhou population.

CONCLUSIONS

In predicting pediatric HBP, original ABSI and modified ABSI underperform BMI and WC.

IMPACT

The current study is the first to evaluate whether original ABSI or modified ABSI is comparable to BMI and WC for screening HBP in children and adolescents. In predicting pediatric HBP, original ABSI and modified ABSI do not perform as well as traditional anthropometric indicators, such as BMI and WC. BMI remains the optimal indicator in pediatric HBP screening. This study provides a theoretical basis for the early identification of HBP in children and adolescents by adopting effective predictors.

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.

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.

A Multilayer Perceptron Neural Network Model to Classify Hypertension in Adolescents Using Anthropometric Measurements: A Cross-Sectional Study in Sarawak, Malaysia

This study outlines and developed a multilayer perceptron (MLP) neural network model for adolescent hypertension classification focusing on the use of simple anthropometric and sociodemographic data collected from a cross-sectional research study in Sarawak, Malaysia. Among the 2,461 data collected, 741 were hypertensive (30.1%) and 1720 were normal (69.9%). During the data gathering process, eleven anthropometric measurements and sociodemographic data were collected. The variable selection procedure in the methodology proposed selected five parameters: weight, weight-to-height ratio (WHtR), age, sex, and ethnicity, as the input of the network model. The developed MLP model with a single hidden layer of 50 hidden neurons managed to achieve a sensitivity of 0.41, specificity of 0.91, precision of 0.65, F-score of 0.50, accuracy of 0.76, and Area Under the Receiver Operating Characteristic (ROC) Curve (AUC) of 0.75 using the imbalanced data set. Analyzing the performance metrics obtained from the training, validation and testing data sets show that the developed network model is well-generalized. Using Bayes' Theorem, an adolescent classified as hypertensive using this created model has a 66.2% likelihood of having hypertension in the Sarawak adolescent population, which has a hypertension prevalence of 30.1%. When the prevalence of hypertension in the Sarawak population was increased to 50%, the developed model could predict an adolescent having hypertension with an 82.0% chance, whereas when the prevalence of hypertension was reduced to 10%, the developed model could only predict true positive hypertension with a 33.6% chance. With the sensitivity of the model increasing to 65% and 90% while retaining a specificity of 91%, the true positivity of an adolescent being hypertension would be 75.7% and 81.2%, respectively, according to Bayes' Theorem. The findings show that simple anthropometric measurements paired with sociodemographic data are feasible to be used to classify hypertension in adolescents using the developed MLP model in Sarawak adolescent population with modest hypertension prevalence. However, a model with higher sensitivity and specificity is required for better positive hypertension predictive value when the prevalence is low. We conclude that the developed classification model could serve as a quick and easy preliminary warning tool for screening high-risk adolescents of developing hypertension.

Anthropometric indices of obesity as predictors of high blood pressure among school children

BACKGROUND

Hypertension is related to increased body fat, which can be evaluated by anthropometric indicators. The aim of this study was to determine the predictive power of anthropometric indicators and to establish their cutoff points as discriminators of high blood pressure.

METHODS

A cross-sectional study was conducted on 793 schoolchildren aged 10-14 years. Six anthropometric indices were used: body mass index-z-score (BMI-z-score), waist circumference (WC), waist-toheight ratio (WHtR), a body shape index (ABSI), body roundness index (BRI) and conicity index (CI). Elevated blood pressure (EBP) and hypertension (HTN) were characterized by values ≥ 90th and <95th percentile and ≥ 95th percentile for systolic and/or diastolic blood pressure, respectively. The predictive power of anthropometric indices was analyzed by sex using the receiver operating characteristic curve (ROC).

RESULTS

The prevalence of EBP and HTN was 11.0% and 14.8%, respectively. According to the analyses of the ROC curve, WC provided the largest area under the curve (AUC) value, while CI showed the lowest AUC value in predicting elevated blood pressure in the total sample. The BMI z-score provided the largest area under the curve (AUC) value (0.722), followed by WHtR (0.709) and BRI (0.709), in predicting hypertension in boys.

CONCLUSIONS

BMI z-score and WC may be the best predictors of EBP and BMI z-score for HTN among Jordanian schoolchildren.

Prevalence and Risk Factors for Hypertension in Adolescents Aged 12 to 17 Years: A School-Based Study in China

[Figure: see text].

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.

Association of a body shape index and hip index with cardiometabolic risk factors in children and adolescents: the CASPIAN-V study

OBJECTIVE

This study designed to discover the link between a body shape index (ABSI) and hip index (HI) with cardiometabolic risk factors (CMRFs) in Iranian children and adolescents.

SUBJECTS AND METHODS

In a nationwide cross-sectional survey, 4200 students who were 7-18 years old were chosen via a multistage cluster sampling method in 30 provinces of Iran in 2015. Metabolic syndrome (MetS) was defined in line with the Adult Treatment Panel III criteria. ABSI and HI were defined as waist circumference (m)/ [body mass index 2/3 * height (m)1/2] and hip circumference (cm) *(height/ 166 cm)0.310 *(weight / 73 kg)-0.482 respectively. Association between ABSI and HI with CMRFs as categorical and continuous variables were evaluated using multivariable logistic and linear regression analysis respectively.

RESULTS

Totally, information of 14,002 students and findings of blood samples of 3483 of them were involved in the current study. In the multivariable logistic regression, an association of HI with high triglyceride (TG) (OR: 0.99, 95 % CI: 0.98-0.99) and ABSI with MetS (OR: 11.41, 2.61-49.88) was statistically significant (P < 0.05). Also, both indices were significantly associated with overweight, generalized, and abdominal obesity. In the multivariable linear regression analysis, increasing HI (per one unit) was associated with body mass index z-score (z-BMI) (β: -0.01), waist circumference (WC) (β: 0.15), TG (β: -0.16), and systolic blood pressure (SBP) (β: -0.02). Moreover, in the multivariable linear models, ABSI was significantly associated with z-BMI, WC, SBP, and diastolic blood pressure (P < 0.001).

CONCLUSIONS

ABSI and HI as novel body shape indices were significantly associated with some CMRFs. Therefore, these indices can be used as some useful anthropometric risk indices for predicting MetS.

A comparison between body mass index and waist circumference for identifying continuous metabolic syndrome risk score components in Iranian school-aged children using a structural equation modeling approach: the CASPIAN-V study

PURPOSE

The purpose of this study was to investigate the association of anthropometric indices with continuous metabolic syndrome (cMetS) risk score components in a large population-based sample of children and adolescents.

METHODS

This multi-centric study was performed on 3843 students aged 7-18 years who were selected by multistage, stratified cluster sampling method from 30 provinces of Iran. Demographic, anthropometric and biochemical factors were obtained and standardized residuals (z-scores) were calculated for MetS components. A structural equation modeling approach was applied to evaluate the relationships among the study variables and to implement the subsequent structural modeling.

RESULTS

The mean age of the participants (52.3% boys) was 12.4 ± 3.05 years. Standardized scores of body mass index (ZBMI) and waist circumference (ZWC) had a direct effect on standardized scores of mean arterial pressure (ZMAP) (0.23 and 0.24 in boys and 0.22 and 0.23 in girls, respectively) and triglyceride (ZTG) (0.07 and 0.04 in boys and 0.02 and 0.06 in girls, respectively), but the effect of ZWC was stronger than ZBMI on these variables. Age, socioeconomic status and sedentary behaviors showed a positive direct effect on ZWC (0.01, 0.05 and 0.07 in boys and 0.05, 0.08 and 0.002 in girls, respectively). These variables induced indirect effects on cMets risk score components through ZWC.

CONCLUSION

The magnitude of association between WC and continuous metabolic syndrome risk score components was higher compared to BMI in school-aged children, emphasizing on paying more attention to central obesity in childhood.

LEVEL OF EVIDENCE

Level V, cross-sectional descriptive study.