Background and aims To examine the association of dietary behaviors, lifestyle, and biochemical factors with metabolic phenotypes of obesity among obese Iranian children and adolescents. Methods This cross-sectional study was conducted within the framework of the fifth phase of CASPIAN study. Of 3840 students aged 7–18 years of 30 Iranian provinces, 408 subjects were diagnosed as obese; they were divided into metabolically healthy obese (MHO) and metabolically unhealthy obese (MUO) groups. Biochemical factors, anthropometric measures, dietary, and lifestyle habits were compared between groups. Results Of the 408 obese subjects, 68 (16.7%) were the MUO; the remaining 340 (84.3%) fall in the MHO group. The MUO group had significantly higher systolic and diastolic BPs, FBS, TG, ALT, anthropometric measures, and lower HDL levels than MHO groups (all p-value < 0.05). The frequency of high birth weight (> 4000 gr) was significantly higher in the MUO group than the MHO group (p-value: 0.04). A higher percentage of individuals with breastfeeding duration ≥ 6 month was found in the MUO group (95.5% (95% CI 86.1–98.6%)) compared to MHO group (85.7% (95% CI 80.4–89.7%)) (p-value = 0.04). Among dietary and lifestyle-related behaviors, only the frequency of salty snack consumption and eating food according to the parents’ request was significantly higher in the MUO group than the MHO group (p-value < 0.05). Conclusion Dietary habits and lifestyle factors may determine the obesity phenotypes in children and adolescents.

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This study aimed to evaluate the accuracy and performance of modified blood pressure‐to‐height ratio (MBPHR) for identifying high blood pressure (HBP) in a large population of children. This multicentric cross‐sectional study was conducted on a nationally representative sample of 7349 Iranian students aged 7‐12 years living in 30 provinces in Iran. High systolic blood pressure and diastolic blood pressure were defined according to the 2017 American Academy of Pediatrics (AAP) guidelines. The BP‐to height ratio (BPHR) was calculated as BP (mmHg)/height (cm), MBPHR3 as BP (mmHg)/(height (cm) + 3 (13‐age)), and MBPHR7 as BP (mmHg)/(height (cm) + 7 (13‐age). The receiver‐operating characteristic curve analysis was used to evaluate the performance of these three ratios for identification of HBP in children compared to the 2017 AAP guidelines as the gold standard. Mean age of participants was 12.29 ± 3.15 years and 3736 (50.8%) were girls. The prevalence of HBP was 11.9% (11.5% in boys, 12.3% in girls). The area under the curve (AUC) was higher for MSBPHR3/MDBPHR3 (0.97/0.98) than MSBPHR7/MDBPHR7 (0.96/0.97) and SBPHR/DBPHR (0.96/0.95) for identifying high Systolic and diastolic BP. The optimal cut‐off points for MSBPHR3/MDBPH, MSBPHR7/MDBPHR7, and SBPHR/DBPHR were 0.76/0.50, 0.69/0.46, and 0.81/0.52 respectively. Negative predictive value was nearly perfect for three ratios (≥98%). Positive predictive value was higher for MBPHR3 (52.7%) than MBPHR7 (51.0%) and BPHR (39.8%). Overall, MBPHR3 had better performance than MBPHR7 and BPHR for identification of HBP in Iranian children and it may improve early hypertension recognition and control in primary screening.

Anthropometric indices have been used as indicators for predicting hypertension (HTN) in children and adolescents but it is not clear which anthropometric measures are a better index for identifying elevated blood pressure (EBP) risk factors in pediatric population. Body mass index (BMI), waist circumference (WC), weight‐height ratio (WHR), a body shape index (ABSI) and blood pressure were measured in 14 008 children and adolescents aged 7‐18 years in a national school‐aged survey CASPIN V. Hypertension (HTN) was defined according to the 2017 American Academy of Pediatrics guidelines, using the 95th percentile. The predictive power of anthropometric indices for HTN risk factors was examined using receiver operating characteristic (ROC) analyses. Multivariate logistic regression analysis was used to compare areas under ROC curves (AUCs) among the four anthropometric indices. BMI, WC, WHR, and ABSI were significantly higher in adolescents than in children. EBP was more prevalent in boys (7.2%) than girls (5.5%), whereas the prevalence of HTN was higher in girls (11.3%) than boys 10.4%. Prevalence odds ratio was around 2 for BMI, WC, and WHR with AUCs scores of nearly 0.6 to predict EBP in both children and adolescents of both sexes. Thus, the ability of BMI z‐score, WC, WHR or ASBI to identify Iranian children and adolescents at higher risk of EBP was week. WC, WHR or ASBI in combination with BMI did not improve predictive power to identify subjects at higher risk of EBP.