title: Is the association of continuous metabolic syndrome risk score with body mass index independent of physical activity? The CASPIAN-III study.
abstract: OBJECTIVE
  Although the association of body mass index (BMI) with metabolic syndrome (MetS) is well documented, there is little knowledge on the independent and joint associations of BMI and physical activity with MetS risk based on a continuous scoring system. This study was designed to explore the effect of physical activity on interactions between excess body weight and continuous metabolic syndrome (cMetS) in a nationwide survey of Iranian children and adolescents.
  
  
  METHODS
  Data on 5,625 school students between 10 and 18 years of age were analyzed. BMI percentiles, screen time activity (STA), leisure time physical activity (LTPA) levels, and components of cMetS risk score were extracted. Standardized residuals (z-scores) were calculated for MetS components. Linear regression models were used to study the interactions between different combinations of cMetS, LTPA, and BMI percentiles.
  
  
  RESULTS
  Overall, 984 (17.5%) subjects were underweight, whereas 501 (8.9%) and 451 (8%) participants were overweight and obese, respectively. All standardized values for cMetS components, except fasting blood glucose level, were directly correlated with BMI percentiles in all models (P-trend < 0.001); these associations were independent of STA and LTPA levels. Linear associations were also observed among LTPA and standardized residuals for blood pressure, high-density lipoprotein, and waist circumference (P-trend < 0.01).
  
  
  CONCLUSIONS
  Our findings suggest that BMI percentiles are associated with cMetS risk score independent of LTPA and STA levels.
authors.affiliation: Chronic Diseases Research Center, Endocrinology and Metabolism Population Sciences Institute, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Ramin
authors.initials: R
authors.lastname: Heshmat
authors.affiliation: Chronic Diseases Research Center, Endocrinology and Metabolism Population Sciences Institute, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Gita
authors.initials: G
authors.lastname: Shafiee
authors.affiliation: Child Growth and Development Research Center, Research Institute for Primordial Prevention of Non-communicable Disease, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Roya
authors.initials: R
authors.lastname: Kelishadi
authors.affiliation: Research Department, Tehran Heart Center, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Amir Eslami Shahr
authors.initials: AE
authors.lastname: Babaki
authors.affiliation: Department of Pediatrics, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.
authors.forename: Mohammad Esmaeil
authors.initials: ME
authors.lastname: Motlagh
authors.affiliation: Department of Exercise Physiology, Science and Research Branch, Islamic Azad University, Tehran, Iran.
authors.forename: Tahereh
authors.initials: T
authors.lastname: Arefirad
authors.affiliation: Child Growth and Development Research Center, Research Institute for Primordial Prevention of Non-communicable Disease, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Gelayol
authors.initials: G
authors.lastname: Ardalan
authors.affiliation: Department of Nutrition, Faculty of Medicine, Science and Research Branch, Islamic Azad University, Tehran, Iran.
authors.forename: Asal
authors.initials: A
authors.lastname: Ataie-Jafari
authors.affiliation: Department of Medical Emergencies, Qom University of Medical Sciences, Qom, Iran.
authors.forename: Hamid
authors.initials: H
authors.lastname: Asayesh
authors.affiliation: Department of Epidemiology, School of Public Health, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Rasool
authors.initials: R
authors.lastname: Mohammadi
authors.affiliation: Department of Community Medicine, School of Public Health, Alborz University of Medical Sciences, Baghestan Boulevard, 31485/56, Karaj, Iran. ; Chronic Diseases Research Center, Endocrinology and Metabolism Population Sciences Institute, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Mostafa
authors.initials: M
authors.lastname: Qorbani
keywords: BMI; metabolic syndrome; physical activity