25-Hydroxyvitamin D and glycemic control: A cross-sectional study of children and adolescents with type 1 diabetes

Diabetes Res Clin Pract. 2016 May:115:54-9. doi: 10.1016/j.diabres.2016.03.002. Epub 2016 Mar 12.


Aim: The objective of this study was to describe the vitamin D status of children and adolescents with type 1 diabetes and to evaluate whether levels of 25-hydroxyvitamin D are significantly associated with HbA1c in this population.

Methods: 197 children and adolescents from a diabetes center in a children's hospital were recruited during regular follow up visit. Non-fasting blood samples were collected to measure 25-hydroxyvitamin D and blood glucose levels. HbA1c and other key variables were abstracted from patients' medical records.

Results: Of the 197 children and adolescents, more than half were adolescents, males, and Caucasian. 23% were overweight, while 13% were obese. Mean HbA1c was 8.6±1.4% (70±15.3mmol/mol). 40.6% of patients had 25-hydroxyvitamin D levels ≤50nmol/L; 49.2% had 25-hydroxyvitamin D levels between 51 and 75nmol/L and 10.2% had 25-hydroxyvitamin D levels >75nmol/L. The bivariate relationship between 25-hydroxyvitamin D and HbA1c almost reached statistical significance (P=0.057), while no significance was established in the multivariate model.

Conclusions: To the best of our knowledge this is the first study that has been adequately-powered to examine the association between 25-hydroxyvitamin D and HbA1c in children and adolescents with T1DM. This study demonstrated the high prevalence of patients with low levels of 25-hydroxyvitamin D specifically in healthy weight and Caucasian children and adolescents with T1DM. These data suggest the need for monitoring of 25-hydroxyvitamin D in all youth with T1DM.

Keywords: 25-Hydroxyvitamin D; HbA1c; Type 1 diabetes.

MeSH terms

  • Adolescent
  • Blood Glucose
  • Body Weight
  • Child
  • Cross-Sectional Studies
  • Diabetes Mellitus, Type 1 / blood*
  • Diabetes Mellitus, Type 1 / drug therapy
  • Female
  • Humans
  • Insulin / therapeutic use
  • Male
  • Prevalence
  • Vitamin D / analogs & derivatives*
  • Vitamin D / blood
  • Vitamin D Deficiency / blood
  • Vitamin D Deficiency / epidemiology


  • Blood Glucose
  • Insulin
  • Vitamin D
  • 25-hydroxyvitamin D