Does Vitamin D Supplementation Improve Glycaemic Control In Children With Type 1 Diabetes Mellitus? - A Randomized Controlled Trial.

Introduction: Vitamin D endocrine system is a potential immune system modulator and has been implicated in the pathogenesis of several autoimmune diseases including Type 1 Diabetes Mellitus (T1DM). Studies have demonstrated an inverse risk relationship between T1DM and Vitamin D levels and also, shown a reduced risk of the disease with its supplementation.

Aim: To evaluate the role of Vitamin D as an adjuvant in improving glycaemic control and residual pancreatic beta-cell function. Primary outcome was the mean change in HbA1c levels over a period of six months.

Materials And Methods: This double-blinded randomized controlled trial was done in a tertiary care hospital, Southern India and included 52 children aged 1-18 years with T1DM, with 26 participants each in the intervention and standard of care arm. Oral Vitamin D therapy was administered once a month for six months in addition to insulin in intervention arm while only insulin was continued for other arm. Plasma HbA1c, serum 25-Hydroxy vitamin D (25OHD), insulin dose and C-peptide were measured at baseline and repeated after 6 months.

Results: Prevalence of Vitamin D deficiency was as high as 63.5% i.e., 33 of total 52 children with T1DM. The mean C-peptide levels were significantly high in intervention arm as compared to standard of care after six months. However, there was no significant difference in HbA1c, and insulin requirement at six months between the two groups. No adverse events due to Vitamin D therapy were noted.

Conclusion: Oral Vitamin D may serve as an adjuvant to insulin therapy for children with T1DM by augmenting residual beta-cell function and improving insulin secretion. However, a significant decrease in HbA1c level and requirement for exogenous insulin was not achieved in our study.