title: Serum vitamin D status in children and adolescence with diabetes according to season and age.
abstract: OBJECTIVE
  It is known that children with diabetes have more severe vitamin D deficiency than healthy children. This study aimed to investigate serum vitamin D status and analyze the relationships between serum vitamin D levels and clinical parameters in children with diabetes.
  
  
  METHODS
  We checked serum vitamin D levels of children with diabetes aged below 18 years who were treated at our Department of Pediatrics between December 2011 and February 2012 (winter) as well as between June 2012 and August 2012 (summer). We retrospectively analyzed relationships between their serum vitamin D levels and clinical parameters.
  
  
  RESULTS
  The serum 25-hydroxyvitamin D level in children with diabetes during winter was markedly lower than during summer (10.8±5.1 ng/mL vs. 17.6±5.6 ng/mL); vitamin D deficiency was more prevalent during winter (95% vs. 62%). However, there was no difference between children with diabetes and healthy children. In children with type I diabetes mellitus, among all the clinical parameters, age had the greatest negative correlation with serum vitamin D level.
  
  
  CONCLUSIONS
  In children with diabetes, serum vitamin D levels showed marked seasonal variation. However, no clear relationship was identified between vitamin D deficiency and diabetes. This was because the control group had an equally high vitamin D deficiency rate. Additional studies including other clinical parameters after vitamin D supplementation in children with diabetes should be considered.
authors.affiliation: Department of Pediatrics, Chonbuk National University Medical School, Jeonju, Korea.
authors.forename: Sung Su
authors.initials: SS
authors.lastname: Jung
authors.affiliation: Department of Pediatrics, Chonbuk National University Medical School, Jeonju, Korea.
authors.forename: Min Sun
authors.initials: MS
authors.lastname: Kim
authors.affiliation: Department of Pediatrics, Chonbuk National University Medical School, Jeonju, Korea.
authors.forename: Dae Yeol
authors.initials: DY
authors.lastname: Lee
keywords: Age; Child; Diabetes mellitus; Seasons; Vitamin D