Endocrine Abstracts

Background: In recent years, the role of vitamin D in improving the profile of inflammatory markers in order to prevent and treat diabetic neuropathy and microcirculation disorders has been actively studied.

Aims: The research goal was to study the dynamics of inflammatory markers, clinical manifestations of diabetic peripheral neuropathy and laser Doppler flowmetry of skin microcirculation during treatment with various doses of cholecalciferol in patients with type 2 diabetes and DPN.

Materials and methods: A single-center, open, randomized trial included patients with type 2 diabetes with DPN. Sixty-seven patients were randomized into 2 groups, where Group I took cholecalciferol in a dose of 5,000 IU/week for 24 weeks, and Group II took a dose of 40,000 IU/week. At the start and the end of the trial, the body mass index (BMI), glycated hemoglobin level (HbA1c), 25(OH)D, PTH, interleukins-1β, −6, −10 (IL), C-reactive protein (CRP), and tumor necrosis factor α (TNFα) levels were determined; the survey was conducted on the NSS, NDS and visual analog scales. Using laser Doppler flowmetry, one compared the initial and final indicators of the baseline blood flow and microcirculation (MC) against functional samples (postural and occlusal). Control measurements of LDF parameters were performed on 16 subjects without diabetes mellitus (eight men/eight women, 51.8 ± 3.7 years).

Results: Sixty-two patients completed the study. Group I (n = 31, W16) and Group II (n = 31, W15) were initially comparable by age, gender, BMI, HbA1c level, NSS, NDS, and VAS. Initially, LDF indicators were significantly lower compared to the group without T2DM. Vitamin D deficiency was detected in 78% of patients with T2DM. After 24 weeks of taking cholecalciferol in Group II, there was a significant decrease in BMI, in the levels of HbA1c and IL-6, and an increase in the level of IL-10, as well as the improvement of cutaneous MC and functional test parameters, while in Group I these changes were not detected. A correlation was established between the final level 25(OH)D and IL-6 (r = −0.378, P = 0.036), IL-10 (r = 0.483, P = 0.006), BMI (r = −0.388, P = 0.031) and HbA1c (r = −0.388, P = 0.031).

Conclusion: Receiving cholecalciferol in a dose of 40,000 IU/week over the course of 24 weeks is associated with a decrease in BMI, an improvement in glycemic control and the profile of pro-inflammatory markers, a decrease in the severity of diabetic peripheral neuropathy, and an improvement in the LDF parameters of cutaneous MC and functional tests in patients with type 2 diabetes and DPN