title: Obesity in Youth with Type 1 Diabetes in Germany, Austria, and the United States.
abstract: OBJECTIVE
  To examine the current extent of the obesity problem in 2 large pediatric clinical registries in the US and Europe and to examine the hypotheses that increased body mass index (BMI) z-scores (BMIz) are associated with greater hemoglobin A1c (HbA1c) and increased frequency of severe hypoglycemia in youth with type 1 diabetes (T1D).
  
  
  METHODS
  International (World Health Organization) and national (Centers for Disease Control and Prevention/German Health Interview and Examination Survey for Children and Adolescents) BMI references were used to calculate BMIz in participants (age 2-<18 years and ≥ 1 year duration of T1D) enrolled in the T1D Exchange (n = 11,435) and the Diabetes Prospective Follow-up (n = 21,501). Associations between BMIz and HbA1c and severe hypoglycemia were assessed.
  
  
  RESULTS
  Participants in both registries had median BMI values that were greater than international and their respective national reference values. BMIz was significantly greater in the T1D Exchange vs the Diabetes Prospective Follow-up (P < .001). After stratification by age-group, no differences in BMI between registries existed for children 2-5 years, but differences were confirmed for 6- to 9-, 10- to 13-, and 14- to 17-year age groups (all P < .001). Greater BMIz were significantly related to greater HbA1c levels and more frequent occurrence of severe hypoglycemia across the registries, although these associations may not be clinically relevant.
  
  
  CONCLUSIONS
  Excessive weight is a common problem in children with T1D in Germany and Austria and, especially, in the US. Our data suggest that obesity contributes to the challenges in achieving optimal glycemic control in children and adolescents with T1D.
authors.affiliation: Jaeb Center for Health Research, Tampa, FL. Electronic address: T1DStats@jaeb.org.
authors.forename: Stephanie N
authors.initials: SN
authors.lastname: DuBose
authors.affiliation: Institute for Epidemiology and Medical Biometry, ZIBMT, University of Ulm, Ulm, Germany.
authors.forename: Julia M
authors.initials: JM
authors.lastname: Hermann
authors.affiliation: Yale University, New Haven, CT.
authors.forename: William V
authors.initials: WV
authors.lastname: Tamborlane
authors.affiliation: Jaeb Center for Health Research, Tampa, FL.
authors.forename: Roy W
authors.initials: RW
authors.lastname: Beck
authors.affiliation: Department of Pediatrics, University Children's Hospital Jena, Jena, Germany.
authors.forename: Axel
authors.initials: A
authors.lastname: Dost
authors.affiliation: Indiana University School of Medicine, Indianapolis, IN.
authors.forename: Linda A
authors.initials: LA
authors.lastname: DiMeglio
authors.affiliation: University Children's Hospital Freiburg, Freiburg, Germany.
authors.forename: Karl Otfried
authors.initials: KO
authors.lastname: Schwab
authors.affiliation: Institute for Epidemiology and Medical Biometry, ZIBMT, University of Ulm, Ulm, Germany.
authors.forename: Reinhard W
authors.initials: RW
authors.lastname: Holl
authors.affiliation: Department of Pediatrics, Medical University of Innsbruck, Innsbruck, Austria.
authors.forename: Sabine E
authors.initials: SE
authors.lastname: Hofer
authors.affiliation: Barbara Davis Center for Childhood Diabetes, Aurora, CO.
authors.forename: David M
authors.initials: DM
authors.lastname: Maahs
mesh_terms: D000293:Adolescent; D001317:Austria / Q000453:epidemiology; D015992:Body Mass Index; D002648:Child; D002675:Child, Preschool; D003922:Diabetes Mellitus, Type 1 / Q000453:epidemiology*; D005260:Female; D005858:Germany / Q000453:epidemiology; D006442:Glycated Hemoglobin / Q000032:analysis; D006801:Humans; D007003:Hypoglycemia / Q000453:epidemiology; D008297:Male; D009765:Obesity / Q000453:epidemiology*; D012042:Registries; D014481:United States / Q000453:epidemiology
chemical_list: D006442:Glycated Hemoglobin; C517652:hemoglobin A1c protein, human