Tehran University of Medical Sciences Iranian Journal of Public Health 2251-6085 46 3 2017 03 14 368 379 Neamatollah ATAEI Pediatric Chronic Kidney Disease Research Center, The Children's Hospital Medical Center, Tehran University of Medical Sciences, Tehran, Iran AND Dept. of Pediatric Nephrology, The Children’s Hospital Medical Center, Faculty of Medicine, Tehran University of Medical Sciences, Tehran, Iran Masoud BAIKPOUR Dept. of Medicine, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran Mostafa HOSSEINI Dept. of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran Mahmoud YOUSEFIFARD Physiology Research Center and Dept. of Physiology, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran Mohammad FAYAZ Dept. of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran Fatemeh ATAEI Pediatric Chronic Kidney Disease Research Center, The Children's Hospital Medical Center, Tehran University of Medical Sciences, Tehran, Iran AND Dept. of Nuclear Medicine, Taleghani Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran Arash ABBASI Pediatric Chronic Kidney Disease Research Center, The Children's Hospital Medical Center, Tehran University of Medical Sciences, Tehran, Iran AND Dept. of Pediatric Nephrology, The Children’s Hospital Medical Center, Faculty of Medicine, Tehran University of Medical Sciences, Tehran, Iran 2017 03 14 2017 03 14 Background: Normal standard references of blood pressure (BP) for children and adolescents should be constructed according to anthropometric indices. Therefore, we aimed to produce BP reference percentiles by body mass index (BMI). Methods: Data on demographic characteristics, anthropometric indices and BP values of 16246 3-18-year-old children and adolescents from 3 cross-sectional studies conducted in Tehran were included. To justify the need for BMI adjustment, quantile regression model was applied for different percentiles of systolic and diastolic BPs with age, sex, and the corresponding BMI percentiles. Then, Age- and sex-specific BP nomograms were constructed according to BMI. Results: All regression coefficients for BMI percentiles were significant in quantile regression of BPs, confirming the necessity for BMI-adjusted nomograms of BP. The BP percentiles for each gender by age and BMI are presented. All the BP percentiles rose steadily in all BMI percentiles with minor discrepancies between the two genders. As observed, the prevalence of hypertension is estimated to be lower among the lean subjects and higher among overweighs when the BMI-adjusted BP curves are considered. Conclusion: The reference database constructed in this survey is the first Iranian BP reference by age and BMI in children and adolescents, from it concluded that BMI-adjusted BP curves depict a more precise picture of the hypertension prevalence and present a more reliable classification standard for hypertension.     https://ijph.tums.ac.ir/index.php/ijph/article/view/9391 https://ijph.tums.ac.ir/index.php/ijph/article/download/9391/5648