title: Longitudinal associations of lifestyle factors and weight status with insulin resistance (HOMA-IR) in preadolescent children: the large prospective cohort study IDEFICS.
abstract: This study investigates prospective associations of anthropometrical and lifestyle indices with insulin resistance (IR) in European children from the IDEFICS cohort. Insulin resistance (IR) is a growing concern in childhood obesity and a central aspect of the metabolic syndrome (MS). It most likely represents the link between obesity and type 2 diabetes.
  
  
  
  This longitudinal study included 3348 preadolescent children aged 3 to 10.9 years from 8 European countries who were observed from 2007/2008 to 2009/2010. The main outcome measure in the present analysis is HOMA-IR (homeostasis model assessment as a common proxy indicator to quantify IR) at follow-up and in its longitudinal development. Anthropometrical measures and lifestyle indices, including objectively determined physical activity, were considered, among others factors, as determinants of IR. Prospective associations between IR at follow-up and anthropometrical and lifestyle indices were estimated by logistic regression models.
  
  
  
  Country-specific prevalence rates of IR in the IDEFICS cohort of European children showed a positive trend with weight category. Prospective multivariate analyses showed the strongest positive associations of IR with BMI z-score (OR = 2.6 for unit change from the mean, 95 % CI 2.1-3.1) and z-score of waist circumference (OR = 2.2 for unit change from the mean, 95 % CI 1.9-2.6), which were analysed in separate models, but also for sex (OR = 2.2 for girls vs. boys, 95 % CI 1.5-3.1 up to OR 2.5, 95 % CI 1.8-3.6 depending on the model), audio-visual media time (OR = 1.2 for an additional hour per day, 95 % CI 1.0-1.4 in both models) and an inverse association of objectively determined physical activity (OR = 0.5 for 3(rd) compared to 1(st) quartile, 95 % CI 0.3-0.9 in both models). A longitudinal reduction of HOMA-IR was accompanied with a parallel decline in BMI.
  
  
  
  This study is, to our knowledge, the first prospective study on IR in a preadolescent children's population. It supports the common hypothesis that overweight and obesity are the main determinants of IR. Our data also indicate that physical inactivity and a sedentary lifestyle are likewise associated with the development of IR, independent of weight status. The promotion of physical activity should thus be considered as an equal option to dietary intervention for the treatment of IR in the paediatric practice.
authors: Leibniz Institute for Prevention Research and Epidemiology - BIPS, Bremen, Germany.|Faculty of Human and Health Sciences, Institute for Public Health and Nursing Research, Bremen University, Bremen, Germany.
authors: Jenny
authors: J
authors: Peplies
authors: Leibniz Institute for Prevention Research and Epidemiology - BIPS, Bremen, Germany.
authors: Claudia
authors: C
authors: Börnhorst
authors: Leibniz Institute for Prevention Research and Epidemiology - BIPS, Bremen, Germany.
authors: Kathrin
authors: K
authors: Günther
authors: MVZ Dortmund Dr. Eberhard und Partner, Dortmund, Germany.
authors: Arno
authors: A
authors: Fraterman
authors: Epidemiology & Population Genetics, Institute of Food Sciences, CNR, Avellino, Italy.
authors: Paola
authors: P
authors: Russo
authors: National Institute for Health Development, Tallinn, Estonia.
authors: Toomas
authors: T
authors: Veidebaum
authors: Research & Education Institute of Child Health, Strovolos, Cyprus.
authors: Michael
authors: M
authors: Tornaritis
authors: Department of Public Health, Ghent University, Ghent, Belgium.
authors: Stefaan
authors: S
authors: De Henauw
authors: Department of Public Health and Community Medicine, The Queen Silvia Children's Hospital, Göteborg, Sweden.
authors: Staffan
authors: S
authors: Marild
authors: National Institute of Health Promotion, University of Pécs, Gyermekklinika, Pécs, Hungary.
authors: Dénes
authors: D
authors: Molnar
authors: GENUD (Growth, Exercise, Nutrition and Development) Research Group, School of Health Sciences, University of Zaragoza, Zaragoza, Spain.
authors: Luis A
authors: LA
authors: Moreno
authors: Leibniz Institute for Prevention Research and Epidemiology - BIPS, Bremen, Germany. ahrens@bips.uni-bremen.de.|Faculty of Human and Health Sciences, Institute for Public Health and Nursing Research, Bremen University, Bremen, Germany. ahrens@bips.uni-bremen.de.|Epidemiological Methods and Etiologic Research, Leibniz Institute for Prevention Research and Epidemiology - BIPS, Achterstraße 30, 28359, Bremen, Germany. ahrens@bips.uni-bremen.de.
authors: Wolfgang
authors: W
authors: Ahrens
mesh_terms: D015992:Body Mass Index; D001835:Body Weight; D002648:Child; D002675:Child, Preschool; D003924:Diabetes Mellitus, Type 2 / Q000209:etiology*; D005060:Europe / Q000453:epidemiology; D015444:Exercise; D005260:Female; D006801:Humans; D007328:Insulin / Q000097:blood*; D007333:Insulin Resistance; D008019:Life Style; D016015:Logistic Models; D008137:Longitudinal Studies; D008297:Male; D024821:Metabolic Syndrome / Q000150:complications; D016017:Odds Ratio; D050177:Overweight; D063766:Pediatric Obesity / Q000150:complications; D015995:Prevalence; D011446:Prospective Studies; D057185:Sedentary Behavior; D055105:Waist Circumference
chemical_list: D007328:Insulin
keywords: Accelerometer; Cohort study; HOMA-IR; Insulin resistance; Obesity; Physical activity; Pre-pubertal children