Article

Diabetologia

, 54:2779

First online:

No association of vitamin D intake or 25-hydroxyvitamin D levels in childhood with risk of islet autoimmunity and type 1 diabetes: the Diabetes Autoimmunity Study in the Young (DAISY)

  • M. SimpsonAffiliated withDepartment of Epidemiology, Colorado School of Public Health, University of Colorado
  • , H. BradyAffiliated withUniversity of Colorado Boulder
  • , X. YinAffiliated withColorado School of Public Health, Department of Biostatistics and Informatics, University of Colorado
  • , J. SeifertAffiliated withDepartment of Epidemiology, Colorado School of Public Health, University of Colorado
  • , K. BarrigaAffiliated withBarbara Davis Center for Childhood Diabetes, University of Colorado Denver
  • , M. HoffmanAffiliated withBarbara Davis Center for Childhood Diabetes, University of Colorado Denver
  • , T. BugawanAffiliated withRoche Molecular Systems Inc.
  • , A. E. BarónAffiliated withColorado School of Public Health, Department of Biostatistics and Informatics, University of Colorado
  • , R. J. SokolAffiliated withThe Children’s Hospital of Denver
    • , G. EisenbarthAffiliated withBarbara Davis Center for Childhood Diabetes, University of Colorado Denver
    • , H. ErlichAffiliated withRoche Molecular Systems Inc.
    • , M. RewersAffiliated withBarbara Davis Center for Childhood Diabetes, University of Colorado Denver
    • , J. M. NorrisAffiliated withDepartment of Epidemiology, Colorado School of Public Health, University of Colorado Email author 

Abstract

Aims/hypothesis

The aim of the study was to investigate the association between vitamin D intake and status and the risk of islet autoimmunity (IA) and subsequent type 1 diabetes in children at increased risk of type 1 diabetes.

Methods

The Diabetes Autoimmunity Study in the Young (DAISY) in Denver, CO, USA, has been following children at increased risk of diabetes since 1993. As of February 2011, 198 children developed IA during follow-up of 2,644 DAISY children. Vitamin D intake and plasma 25-hydroxyvitamin D [25(OH)D] were measured longitudinally. Proportional hazards regression analyses of time to IA, or type 1 diabetes in IA-positive children, were conducted, with vitamin D intake and 25(OH)D as time-varying covariates. HRs were calculated for a standard deviation difference in exposure, with adjustment for confounders.

Results

Intake of vitamin D was not associated with the risk of IA (adjusted HR 1.13; 95% CI 0.95, 1.35; p = 0.18) nor progression to diabetes in IA-positive children (adjusted HR 1.30; 95% CI 0.91, 1.86; p = 0.15). Moreover, 25(OH)D level was not associated with the risk of IA (adjusted HR 1.12; 95% CI 0.88, 1.43; p = 0.36), nor progression to diabetes in IA-positive children (adjusted HR 0.91; 95% CI 0.68, 1.22; p = 0.54). In the 128 children in whom we measured 25(OH)D at 9 months of age, 25(OH)D was not associated with risk of IA (n = 30 IA-positive children) (adjusted HR 1.02; 95% CI 0.96, 1.07; p = 0.58).

Conclusions/interpretation

Neither vitamin D intake nor 25(OH)D levels throughout childhood were associated with the risk of IA or progression to type 1 diabetes in our population.

Keywords

Diet Islet autoimmunity Type 1 diabetes Vitamin D 25(OH)D