Abstract

Introduction and Aim: Prediabetes is defined as the initial stage of diabetes mellitus. Approximately 25 - 30% of patients with prediabetes progress to diabetes mellitus within the following 5 years. Vitamin D deficiency is an important and common health problem. Observational studies has shown a relationship between low blood 25-hydroxyvitamin D levels and diabetes risk, but it is unclear whether vitamin D supplementation reduces diabetes risk. This study aims to investigate the relationship between vitamin D levels and prediabetes.

Method: Forty-four patients with prediabetes and 40 healthy controls who attended the Departments of Endocrinology and Internal Medicine outpatient clinics of Antalya Training and Research Hospital between 2017 and 2021 were enrolled in the study. The levels of HbA1c, fasting blood glucose, creatinine, sodium, potassium, blood urea nitrogen, total cholesterol, low-density lipoprotein, very low-density lipoprotein, high-density lipoprotein, and triglycerides were measured during the biochemical analysis and if vitamin D deficiency is suspected calcium, phosphorus, albumin, and vitamin D levels were measured. Data of the patients were evaluated retrospectively.

Results: Serum vitamin D levels were significantly lower in patients than controls (p = 0.02). Serum calcium levels were lower in patients than controls but the result was not statistically significant (p = 0.07). A significant inverse or negative correlation was observed between HbA1c (r: -0.32 p = 0.001), fasting blood glucose (r = -0.41, p < 0.001) and vitamin D levels.

Conclusion: Vitamin D levels were found to be significantly lower in prediabetics. There is a significant inverse correlation between fasting blood glucose, HbA1c and vitamin D levels. Prospective studies with a large number of patients are needed to confirm the findings.

Keywords: Prediabetes; Vitamin D; HbA1c; Fasting Blood Glucose

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