Evaluation of Correlation between the Level of Vitamin D and Glycosylated Hemoglobin in Type 2 Diabetic Mellitus and Nondiabetic Mellitus

The pancreas contains Vitamin D (Vit.-D) and an enzyme that regulates insulin levels. Vitamin D deficiency is associated with several severe health conditions, such as cardiovascular disease, diabetes, various cancers, and multiple sclerosis (MS). Therefore, the objective of the current study is to investigate the correlation between Vitamin D levels and glycosylated hemoglobin (HbA1c) in both patients and controls. The study enrolled 163 T2DM (Group I) and 174 healthy (Group II) subjects to estimate the level of Vit.-D and HbA1c in the blood serum of all subjects, using radioimmunoassay and high-performance liquid chromatography, respectively. The results revealed that Group I had a lower level of Vit.-D (17.82 ± 2.23 ng/mL) than Group II. Similarly, they have high HbA1c levels, showing significant ( P < 0.001; Student’s t-test). Further, in Group I, Vit.-D levels were negatively correlated with HbA1c levels ( P < 0.001; r2 = 0.07, linear regression). Group I and II combined analysis revealed an inverse relationship between Vit.-D levels and HbA1c ( P < 0.001; r2 = 0.021). The study concluded a negative correlation between Vit.-D levels and HbA1c levels in T2DM. However, Vit.-D therapy can recover this correlation, which helps control glycemic levels.