title: Infant Growth and Risk of Childhood-Onset Type 1 Diabetes in Children From 2 Scandinavian Birth Cohorts.
abstract: OBJECTIVE
  Type 1 diabetes mellitus is one of the most common chronic diseases with onset in childhood, but environmental risk factors have not been convincingly established.
  
  
  OBJECTIVE
  To test whether increased growth during the first year of life is associated with higher risk of childhood-onset type 1 diabetes.
  
  
  METHODS
  This is a cohort study using information from 2 population-based cohort studies in Norway and Denmark, the Norwegian Mother and Child Cohort Study (MoBa) and the Danish National Birth Cohort (DNBC), of children born between February 1998 and July 2009. The current study was conducted between November 2014 and June 2015.
  
  
  METHODS
  Change in weight and length from birth to age 12 months.
  
  
  METHODS
  Unadjusted and adjusted hazard ratios (HRs) of type 1 diabetes, classified based on nationwide childhood diabetes registers, obtained using Cox proportional hazards regression.
  
  
  RESULTS
  A total of 99,832 children were included in the study, with 59,221 in MoBa (51.2% boys and 48.8% girls; mean age at end of follow-up, 8.6 years [range, 4.6-14.2 years]) and 40,611 in DNBC (50.6% boys and 49.4% girls; mean age at end of follow-up, 13.0 years [range, 10.4-15.7 years]). The incidence rate of type 1 diabetes from age 12 months to the end of follow-up was 25 cases per 100,000 person-years in DNBC and 31 cases per 100,000 person-years in MoBa. The change in weight from birth to 12 months was positively associated with type 1 diabetes (pooled unadjusted HR = 1.24 per 1-SD increase; 95% CI, 1.11-1.39; pooled adjusted HR = 1.24 per 1-SD increase; 95% CI, 1.09-1.41). There was no significant association between length increase from birth to 12 months and type 1 diabetes (pooled unadjusted HR = 1.06 per 1-SD increase; 95% CI, 0.93-1.22; pooled adjusted HR = 1.06 per 1-SD increase; 95% CI, 0.86-1.32). The associations were similar in both sexes.
  
  
  CONCLUSIONS
  This is the first prospective population-based study, to our knowledge, providing evidence that weight increase during the first year of life is positively associated with type 1 diabetes. This supports the early environmental origins of type 1 diabetes.
authors.affiliation: Department of Chronic Diseases, Norwegian Institute of Public Health, Oslo, Norway.
authors.forename: Maria C
authors.initials: MC
authors.lastname: Magnus
authors.affiliation: Centre for Fetal Programming, Department of Epidemiology Research, Statens Serum Institut, Copenhagen, Denmark.
authors.forename: Sjurdur F
authors.initials: SF
authors.lastname: Olsen
authors.affiliation: Centre for Fetal Programming, Department of Epidemiology Research, Statens Serum Institut, Copenhagen, Denmark.
authors.forename: Charlotta
authors.initials: C
authors.lastname: Granström
authors.affiliation: Institute of Clinical Medicine, University of Oslo, Oslo, Norway4Department of Pediatrics, Oslo University Hospital, Oslo, Norway.
authors.forename: Geir
authors.initials: G
authors.lastname: Joner
authors.affiliation: Department of Pediatrics, Oslo University Hospital, Oslo, Norway.
authors.forename: Torild
authors.initials: T
authors.lastname: Skrivarhaug
authors.affiliation: Department of Pediatrics, Copenhagen University Hospital, Herlev, Denmark.
authors.forename: Jannet
authors.initials: J
authors.lastname: Svensson
authors.affiliation: Department of Pediatrics, Copenhagen University Hospital, Herlev, Denmark.
authors.forename: Jesper
authors.initials: J
authors.lastname: Johannesen
authors.affiliation: Department of Pediatrics, Haukeland University Hospital, Bergen, Norway7KG Jebsen Center for Diabetes Research, Department of Clinical Science, University of Bergen, Bergen, Norway.
authors.forename: Pål
authors.initials: P
authors.lastname: Njølstad
authors.affiliation: Institute Management and Staff, Norwegian Institute of Public Health, Oslo, Norway.
authors.forename: Per
authors.initials: P
authors.lastname: Magnus
authors.affiliation: Department of Chronic Diseases, Norwegian Institute of Public Health, Oslo, Norway9Department of Pediatrics, Ostfold Hospital Trust, Fredrikstad, Norway.
authors.forename: Ketil
authors.initials: K
authors.lastname: Størdal
authors.affiliation: Department of Chronic Diseases, Norwegian Institute of Public Health, Oslo, Norway.
authors.forename: Lars C
authors.initials: LC
authors.lastname: Stene
mesh_terms: D000293:Adolescent; D001827:Body Height; D001835:Body Weight; D002648:Child; D002657:Child Development; D002675:Child, Preschool; D015331:Cohort Studies; D003718:Denmark / Q000453:epidemiology; D003922:Diabetes Mellitus, Type 1 / Q000453:epidemiology / Q000209:etiology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D007223:Infant; D008297:Male; D009664:Norway / Q000453:epidemiology; D016016:Proportional Hazards Models; D012307:Risk Factors; D015430:Weight Gain