title: Vitamin D levels at birth and risk of type 1 diabetes in childhood: a case-control study.
abstract: OBJECTIVE
  To assess whether vitamin D levels at birth were associated with risk of having type 1 diabetes up to 10 years of age and the potential modifier effect of ethnic group.
  
  
  METHODS
  The Piedmont Diabetes Registry and the Newborn Screening Regional data were linked to identify cases (n = 67 incident children aged ≤10 years at diabetes onset, 2002-2012) and up to five controls (n = 236) matched for birthday and ethnic group. Cards with neonatal blood spot were used and 25-hydroxyvitamin D(3) assessed with tandem mass spectroscopy.
  
  
  RESULTS
  In conditional logistic regression, OR for unit increment of log vitamin D was 0.78 (95 % CI 0.56-1.10). Vitamin D was significantly lower in migrant than in Italian control newborn babies (p < 0.0001), and interaction between vitamin D and migrant status was statistically significant (p = 0.04). Compared to migrant newborns babies with vitamin D ≥ 2.14 ng/ml, migrants with lower levels had an OR of 14.02 (1.76-111.70), whereas no association was evident in Italians.
  
  
  CONCLUSIONS
  Our case-control study within the Piedmont Diabetes Registry showed no association between vitamin D levels at birth and risk of having type 1 diabetes up to 10 years of age, apart from the subgroup of migrant babies, which might have clinical implications if confirmed.
authors.affiliation: Department of Health Sciences, Amedeo Avogadro University of Eastern Piedmont, Novara, Italy.|IRCAD (Interdisciplinary Research Center of Autoimmune Diseases), Novara, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Cadario
authors.affiliation: Department of Health Sciences, Amedeo Avogadro University of Eastern Piedmont, Novara, Italy.|IRCAD (Interdisciplinary Research Center of Autoimmune Diseases), Novara, Italy.
authors.forename: Silvia
authors.initials: S
authors.lastname: Savastio
authors.affiliation: Department of Pediatrics, Newborn Screening Regional Center, University of Torino, Turin, Italy.
authors.forename: Veronica
authors.initials: V
authors.lastname: Pagliardini
authors.affiliation: Department of Health Sciences, Amedeo Avogadro University of Eastern Piedmont, Novara, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Bagnati
authors.affiliation: Department of Health Sciences, Amedeo Avogadro University of Eastern Piedmont, Novara, Italy.
authors.forename: Matteo
authors.initials: M
authors.lastname: Vidali
authors.affiliation: IRCAD (Interdisciplinary Research Center of Autoimmune Diseases), Novara, Italy.|Department of Pediatrics, University of Turin, Turin, Italy.
authors.forename: Franco
authors.initials: F
authors.lastname: Cerutti
authors.affiliation: Department of Pediatrics, University of Turin, Turin, Italy.
authors.forename: Ivana
authors.initials: I
authors.lastname: Rabbone
authors.affiliation: Pediatric Hospital, Tortona, Italy.
authors.forename: Franco
authors.initials: F
authors.lastname: Fontana
authors.affiliation: Saint Arrigo Pediatric Hospital, Alessandria, Italy.
authors.forename: Riccardo
authors.initials: R
authors.lastname: Lera
authors.affiliation: Pediatrics Hospital, Cuneo, Italy.
authors.forename: Valeria
authors.initials: V
authors.lastname: De Donno
authors.affiliation: Pediatrics Hospital, Vercelli, Italy.
authors.forename: Anna
authors.initials: A
authors.lastname: Valori
authors.affiliation: Department of Medical Sciences, University of Turin, Corso Dogliotti 14, 10126, Turin, Italy.
authors.forename: Gabriella
authors.initials: G
authors.lastname: Gruden
authors.affiliation: Department of Health Sciences, Amedeo Avogadro University of Eastern Piedmont, Novara, Italy.|IRCAD (Interdisciplinary Research Center of Autoimmune Diseases), Novara, Italy.
authors.forename: Gianni
authors.initials: G
authors.lastname: Bona
authors.affiliation: Department of Medical Sciences, University of Turin, Corso Dogliotti 14, 10126, Turin, Italy. graziella.bruno@unito.it.
authors.forename: Graziella
authors.initials: G
authors.lastname: Bruno
mesh_terms: D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D003922:Diabetes Mellitus, Type 1 / Q000097:blood* / Q000453:epidemiology*; D005006:Ethnicity; D005260:Female; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D007558:Italy / Q000453:epidemiology; D008297:Male; D012042:Registries; D018570:Risk Assessment; D014171:Transients and Migrants; D014807:Vitamin D / Q000097:blood*
chemical_list: D014807:Vitamin D
keywords: Epidemiology; Incidence; Migrants