G460(P) Treatment with a single bolus dose of cholecalciferol does not improve HBA1C levels in a cohort of paediatric patients with type one diabetes

Background Intensive glycaemic control in type one diabetes (T1D) reduces progression of complications (DCCT and EDIC). In clinical practice, glycosylated haemoglobin (Hba1c) levels reflect control. Previous studies show that higher 25(OH)D3 levels are associated with lower Hba1c (US SEARCH study). However, there are limited interventional trials assessing the effect of cholecalciferol on Hba1c. Aims. 1. To assess the baseline 25(OH)D3 status in a paediatric cohort of patients with T1D. 2. To determine the effect of cholecalciferol administration on Hba1c. Methods Children with T1D attending routine clinic appointments from February to April 2011 had blood samples taken with consent, and patients with a 25(OH)D3 level 10 years) units. Hba1c levels from the year preceding treatment and the year after treatment were recorded. Results Vitamin D levels were obtained from 51 patients (30 male, 21 female). 35 were Caucasian, 11 South Asian and 5 from other ethnic groups. 42 subjects were vitamin D deficient, but 2 were excluded from the analysis (one moved away, one was non-compliant). All South Asian patients were vitamin D deficient, with mean 25(OH)D3 of 11.2 ng/ml. In Caucasians, there was a negative relationship between baseline 25(OH)D3 level and HbA1C (r= –0.484, p Conclusion We confirmed a high prevalence of vitamin D deficiency in this clinic cohort of children with T1D, and found a negative relationship between baseline 25(OH)D3 level and HbA1C in Caucasians. However, in patients treated with a stat dose of cholecalciferol there was no effect on Hba1c. Further studies with larger sample sizes, and using maintenance 25(OH)D3 therapy rather than stat therapy are required.