Endocrine Abstracts

Objective: Vitamin D deficiency has been shown to alter insulin synthesis and secretion in both humans and animal models. However, less is known on the association between vitamin D and type 2 diabetes mellitus. In the current study we aimed to analyze the relationship between vitamin D levels with glycemic control in type 2 diabetic patients.

Material and methods: Three hundred and twenty diabetic patients who are follow up at least 6 months for diabetes and one hundred fifty five healthy volunteers were included in this study. Physical examination and anthropometric measurement were performed in all the patients. Metabolic and glycemic indicators such as fasting glucose, hemoglobin A1c (A1c), homeostasis model assessment-insulin resistance (HOMA-IR), high-density lipoprotein cholesterol, triglyceride and insulin levels were measured. Also vitamin D and parathyroid hormone (PTH) levels were evaluated in all patients.

Results: Plasma vitamin D levels were significantly lower in diabetic patients than in control group (P=0.025). PTH levels were significantly higher in diabetic patients (P=0.001). Serum calcium, phosphorus and alkaline phosphatase levels were similar between diabetic and control groups. No correlation was observed among plasma vitamin D levels, PTH levels and glycemic parameters. Compared with non-diabetic patients, diabetic patients had high plasma glucose, A1c, HOMA-IR, triglyceride levels as expected.

Conclusion: These results indicate that diabetic patients have low levels of vitamin D. Decreased vitamin D levels could influence the prevalence of diabetes mellitus in a population. To clarify these important points, future prospective studies conducted in larger patient groups.

Declaration of interest: The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.

Funding: This research did not receive any specific grant from any funding agency in the public, commercial or not-for-profit sector.