title: Are serum α- and β-carotene concentrations associated with the development of advanced beta-cell autoimmunity in children with increased genetic susceptibility to type 1 diabetes?
abstract: OBJECTIVE
  Reactive oxygen intermediates have been implicated in mediating the destruction of insulin-producing beta cells and antioxidant nutrients thought to protect against such a process. This study aimed to assess the associations between serum α- and β-carotene concentrations, and the risk of advanced beta-cell autoimmunity, in children with HLA-conferred susceptibility to type 1 diabetes.
  
  
  METHODS
  This case-control study, comprising 108 case children with advanced beta-cell autoimmunity and 216 matched control children, was nested within the nutrition study of the Type 1 Diabetes Prediction and Prevention (DIPP) birth cohort. Serum α- and β-carotene samples were collected each year from the age of 1 to 6 years. For each case-control group, serum samples were analyzed up to the time of seroconversion in the case children. Associations were studied using a conditional logistic-regression model.
  
  
  RESULTS
  Neither serum α- nor β-carotene concentration was significantly associated with the risk of advanced beta-cell autoimmunity. There was marginal evidence (P=0.049) of an inverse association between serum β-carotene concentration and the risk of developing advanced beta-cell autoimmunity at a time closest to seroconversion after adjusting for parental education, maternal age, duration of gestation, diabetes in first-degree relatives, number of earlier deliveries and maternal smoking during pregnancy.
  
  
  CONCLUSIONS
  The present study data provided no clear evidence to support an association between serum α- or β-carotene concentration and advanced beta-cell autoimmunity.
authors.affiliation: Nutrition Unit, Department of Lifestyle and Participation, National Institute for Health and Welfare, Helsinki, Finland. marianne.prasad@thl.ﬁ
authors.forename: M
authors.initials: M
authors.lastname: Prasad
authors.forename: H-M
authors.initials: HM
authors.lastname: Takkinen
authors.forename: J
authors.initials: J
authors.lastname: Nevalainen
authors.forename: M-L
authors.initials: ML
authors.lastname: Ovaskainen
authors.forename: G
authors.initials: G
authors.lastname: Alfthan
authors.forename: L
authors.initials: L
authors.lastname: Uusitalo
authors.forename: M G
authors.initials: MG
authors.lastname: Kenward
authors.forename: R
authors.initials: R
authors.lastname: Veijola
authors.forename: O
authors.initials: O
authors.lastname: Simell
authors.forename: J
authors.initials: J
authors.lastname: Ilonen
authors.forename: M
authors.initials: M
authors.lastname: Knip
authors.forename: S M
authors.initials: SM
authors.lastname: Virtanen
mesh_terms: D015551:Autoimmunity / Q000235:genetics*; D002338:Carotenoids / Q000097:blood*; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D003922:Diabetes Mellitus, Type 1 / Q000097:blood / Q000235:genetics* / Q000276:immunology; D005260:Female; D020022:Genetic Predisposition to Disease; D006680:HLA Antigens / Q000235:genetics; D006801:Humans; D007223:Infant; D050417:Insulin-Secreting Cells / Q000276:immunology*; D011247:Pregnancy; D019207:beta Carotene / Q000097:blood*
chemical_list: D006680:HLA Antigens; D019207:beta Carotene; D002338:Carotenoids; C041635:alpha-carotene