Background: Inflammation plays an important role in the pathogenesis of diabetic neuropathy (DN) in patients with type 2 diabetes (DM2). It seems that vitamin D ((VitD) could be involved in this process, however, the relationship between VitD status and inflammatory markers has not been wildly studied.
Hypothesis: The aim was to study the association between VitD status and inflammatory markers in patients with DM2 and DN.
Methods: The single-centre randomized study included 62 subjects with DM2 and DN (more than 4 points according to NDS), HbA1c up to 9%. Antihyperglycemic treatment was stable during the study. Patients were randomized in two groups: 5000 IU (group I) and 40000 IU (group II) of cholecalciferol supplementation per week. Body mass index (BMI), glycated hemoglobin (HbA1c), serum 25(OH)D level, Interleukins 6, 10 (IL-6, IL-10) were determined at baseline and after 24 weeks of treatment. The correlation analysis was evaluated by Pearson test.
Results: Group I (n = 31, F16) and Group II (n = 31, F15) were matched for age, gender, BMI and baseline HbA1c levels. VitD insufficient/deficiency was revealed in 78% of diabetic patients with DN. After 6 months of VitD supplementation, the BMI, HbA1c and IL-6 levels significantly decreased, and 25(OH)D and IL-10 concentration increased only in Group II. We found associations between serum 25(OH)D and IL-6 (r = -0.912, p = 0.017) as well as IL-10 (r = 0.903, p = 0.014), and between HbA1c and IL-6 (r = 0.825, p = 0.031) and IL-10 (r = -0.897, p = 0.025) exclusively in Group II after treatment.
Conclusions: VitD supplementation in 40000 IU of cholecalciferol per week during 6 months was associated with improved vitamin D status, pro-inflammatory markers and better glycemic control in patients with DM2 and DN. Vitamin D supplementation in 5000 IU per week did not change vitamin D status and inflammatory markers in this population.
A.P. Stepanova: None. T.L. Karonova: None. M. Galagoudza: None. E.Y. Vasileva: None. E.B. Jude: None.