Evaluation of vitamin D, vitamin B12 and Hemoglobin HbA1c levels in patients with type 1 diabetes mellitus

We aimed to evaluate the Vitamin D, Vitamin B12 and Hemoglobin A1c Levels in patients with T1DM. This study is a retrospective cross-sectional study. We classified patients as <7.0% (good glycemic control) and ≥7% (poor glycemic control) based on HbA1c levels. Moreover, we divided the patients into four groups based on serum vitamin D concentrations. This study included 468 patients (257 females and 211 males) with T1DM. The present study revealed that the prevalence of vitamin D deficiency among children with T1DM was very high (49.57%). We found that the vitamin D, vitamin B12, ferritin, HGB and RBC levels were significantly lower in women than in men. The overall prevalence of poor glycemic control was 6.4%. When the groups we divided according to HbA1c levels were compared; we found that the fasting blood glucose and vitamin B12 were significantly lower, while insulin and Mg levels were significantly higher in the good glycemic control group compared to the poor glycemic control group. We found that as vitamin D increases, HbA1c, insulin and creatinine levels decrease, and vitamin B12 levels increases. The negative correlation of vitamin D levels with insulin levels (r:-0.320, p<0.01) and HbA1c levels (r:-0.187, p<0.01) was statistically significant . Our findings showed that, keeping the vitamin D levels high in T1DM patients is important in regulation of glycemic control. Considering the frequency of pernicious anemia in patients with T1DM, it is important to follow vitamin D, vitamin B12 and HbA1c levels in these patients.