ESPE Abstracts

Background: Type 1 diabetes mellitus (T1DM) is an autoimmune and inflammatory process and vitamin D (VD) is thought to reduce inflammation and prevent autoimmune destruction. Studies have shown that VD has an effect on insulin secretion and sensitivity in rats. And it has been shown that adult T2DM with normal levels of VD have decreased insulin requirements. Two prior studies in Turkey looked at the relationship between VD levels and daily insulin requirement in paediatric patients with contradictory results.

Objective and hypotheses: In this study, we will determine if there is a significant correlation between VD levels and HbA1c, daily insulin requirement, BMI, and ethnicity in paediatric T1DM. Our hypothesis is that patients with low VD levels will have increased daily insulin requirement.

Methods: A retrospective chart review of 162 T1DM paediatric patients ages 3–20 years old was conducted. Age, gender, ethnicity, BMI, HgA1c, VD level (25(OH)D), and total daily insulin requirement (units/kg per day) were obtained. VD levels were divided into three groups: <20 ng/ml was considered deficient, 20–29.9 ng/ml insufficient, and >30 ng/ml was sufficient. Multivariate linear regression analysis (using STATA13.1) was used to assess the association between insulin requirement and VD levels adjusting for the following confounders: age, gender, ethnicity, BMI, and HA1c.

Results: The study included 84 girls, 78 boys, 30 African Americans, 27 Hispanics, and 99 Caucasians. Analysis of the data showed that patients with a low VD had a statistically significant (P=0.02) increase in insulin requirement independent of HbA1c levels, age, gender, ethnicity, and BMI.

Conclusion: These findings may suggest that lower levels of VD may contribute to the need for higher insulin doses, which may be related to insulin resistance and suboptimal glucose control in paediatric patients with T1DM.