title: Association between childhood obesity and subsequent Type 1 diabetes: a systematic review and meta-analysis.
abstract: OBJECTIVE
  To review and synthesize the published evidence on the possible association between childhood obesity and the subsequent risk of Type 1 diabetes.
  
  
  METHODS
  The PubMed database was systematically searched for studies using childhood obesity, BMI or %weight-for-height as the exposure variable and subsequent Type 1 diabetes as the outcome. Studies were only included if assessment of obesity preceded the diagnosis of Type 1 diabetes.
  
  
  RESULTS
  Eight case-control studies and one cohort study were included, comprising a total of 2658 cases. Of these nine studies, seven reported a significant association between childhood obesity, BMI or %weight-for-height and increased risk for Type 1 diabetes. Meta-analysis of the four studies that reported childhood obesity as a categorical exposure produced a pooled odds ratio of 2.03 (95% CI 1.46-2.80) for subsequent Type 1 diabetes; however, in those studies, age at obesity assessment varied from age 1 to 12 years. A dose-response relationship was supported by a continuous association between childhood BMI and subsequent Type 1 diabetes in a meta-analysis of five studies (pooled odds ratio 1.25 (95%CI 1.04-1.51) per 1 sd higher BMI).
  
  
  CONCLUSIONS
  There is overall evidence for an association between childhood obesity, or higher BMI, and increased risk of subsequent Type 1 diabetes. Several theories have been proposed for a causal relationship. Reduction in Type 1 diabetes should be considered as a potential additional benefit of preventing childhood obesity.
authors.affiliation: Department of Public Health and Primary Care, University of Cambridge, Cambridge, UK.
authors.forename: K C
authors.initials: KC
authors.lastname: Verbeeten
authors.forename: C E
authors.initials: CE
authors.lastname: Elks
authors.forename: D
authors.initials: D
authors.lastname: Daneman
authors.forename: K K
authors.initials: KK
authors.lastname: Ong
mesh_terms: D017668:Age of Onset; D015992:Body Mass Index; D002648:Child; D002675:Child, Preschool; D003922:Diabetes Mellitus, Type 1 / Q000453:epidemiology* / Q000209:etiology; D005060:Europe / Q000453:epidemiology; D005260:Female; D006801:Humans; D008297:Male; D009765:Obesity / Q000453:epidemiology* / Q000209:etiology; D011446:Prospective Studies; D012307:Risk Factors; D014481:United States / Q000453:epidemiology