25OHVitamin D Levels in a Canarian Pediatric Population with and without Type 1 Diabetes: The Role of Acidosis

The role of Vitamin D in the development of type 1 diabetes (T1D) is controversial. The Canary Islands have the highest incidence of childhood-onset T1D in Spain and one of the highest in Europe. We aimed to evaluate 25OHVitamin D concentrations in a Canarian pediatric population, to assess the existence of seasonal variation, to study their association with T1D, and to evaluate the role of acidosis in its levels. In a retrospective, case-control study, we obtained data from 146 T1D patients (<15 years of age) and 346 control children; 25OHVitamin D concentrations were assessed in serum by automatic ChemiLuminescence ImmunoAssay technology. We found significantly higher 25OHVitamin D levels in the summer and autumn months and an inverse correlation between T1D and age; 25OHVitamin D sufficiency was similar in both groups (44.5% vs. 45.1%), with significant differences in the percentage of patients presenting vitamin D deficiency (11.6% (T1D) vs. 16.4% (controls)). When stratified according to the presence of ketoacidosis at sampling, only patients with acidosis showed lower 25OHVitamin D concentrations than controls. Despite its subtropical geographic location, Vitamin D deficiency is frequent in children in Gran Canaria, and 25OHVitamin D concentrations show seasonal variation. After adjusting for acidosis, no differences were found between children with and without T1D.