Diabetic peripheral neuropathy: the potential role of vitamin D deficiency

Abstract Background Vitamin D is well known for its role in promoting calcium and phosphorus absorption and is recently associated with various neurological disorders. Objective To study the possible relation between vitamin D deficiency and diabetic peripheral neuropathy in a sample of patients recruited from Beni-Suef governorate, north Upper Egypt Methods A case-control study included 25 type 2 diabetic patients with diabetic peripheral neuropathy and 25 healthy controls. The patients included were subjected to clinical evaluation including Michigan Neuropathy Screening Instrument and nerve conduction study. And all patients and control were subjected to assessment of fasting and 2-h post prandial blood sugar, hemoglobin A1C, and serum vitamin D level. Results Serum vitamin D level was significantly lower in patients compared to control (P value = 0.008). For the patients group, females and patients with Michigan neuropathy screening instrument score more than 4 had statistically significant lower vitamin D level (P value = 0.003 and 0.006, respectively). No statistically significant difference in vitamin D level was found between patients below and above the age of 50 years, duration of diabetes less and more than 5 years, different types of diabetes medications, or patients with fair and poor control (P value = 0.525, 0.700, 0.881 and 0.252, respectively). No significant correlation was found between vitamin D level and the results of nerve conduction study. Conclusion Vitamin D deficiency was highly prevalent in diabetic peripheral neuropathy patients. Females and patients with severe form of neuropathy are more liable for lower vitamin D levels