Aim: The aim of the study was to assess vitamin D status in patients with type 2 diabetes (T2D) and diabetic foot ulcers (DFU).

Material and Methods: A total of 224 patients with T2D, mean age 59.2±10.1 years, BMI 31.5±6.3 kg/m2 and eGFR ≥ 45 ml/min/1.73m2, not on vitamin D supplementation, were enrolled in a cross-sectional study. Subjects were divided in two groups - with DFU (n=61) and non-DFU (n=163). The non-DFU group was subdivided into groups with peripheral neuropathy (n=106) and without any complications (n=57). Neuropathy was assessed by standard clinical tests (10g monofilament and 128 Hz tuning fork). Serum 25(OH)D was assessed by ELISA method.

Results: 25(OH)D level was 12.7 ng/ml (IQR 9.35-18.1 ng/ml) in the studied cohort, which is below the sufficient range (sufficient > 30 ng/ml; insufficiency - 20-30 ng/ml; deficiency 10-20 ng/ml, severe deficiency < 10 ng/ml). The DFU group presented with significantly lower 25(OH)D level as compared to non-DFU group, 12.08 ng/ml (IQR 8.5-15.5 ng/ml) vs. 13.50 ng/ml (IQR 9.6-18.6 ng/ml), p=0.006; 86% of DFU patients being with vitamin D deficiency and severe deficiency. There was no difference in diabetes duration (p=0.096), whereas there was a significant difference in eGFR in DFU group as compared to non-DFU group (81±20 ml/min/1.73m² vs. 89±19 ml/min/1.73m², p=0.008). No relationship was established between 25(OH)D levels and BMI in both groups. The subanalysis of non-DFU group demonstrated significantly lower 25(OH)D level in patients with peripheral neuropathy as compared to patients without any complications - 12.5 ng/ml (IQR 9-17 ng/ml) vs. 16.2 ng/ml (IQR 10-21 ng/ml), p=0.027. There was no difference in serum calcium levels between the different groups.

Conclusion: Patients with DFU and diabetic neuropathy are at higher risk of low 25(OH)D levels probably because of poor self-care and less sunlight exposure. Therefore, this population should be screened for vitamin D deficiency as it may lead to poor wound healing.

Disclosure

A.S. Todorova: None. R. Dimova: Consultant; Self; Amgen, Boehringer Ingelheim International GmbH. Speaker’s Bureau; Self; Sanofi, Wörwag Pharma. N. Chakarova: None. M. Serdarova: None. G. Grozeva-Damyanova: None. P. Tsarkova: None. T. Tankova: Board Member; Self; Amgen, Boehringer Ingelheim International GmbH, Eli Lilly and Company, Merck Sharp & Dohme Corp., Mundipharma International, Novo Nordisk A/S, Sanofi. Speaker’s Bureau; Self; AstraZeneca, Boehringer Ingelheim International GmbH, Sanofi, Servier. E.B. Jude: Speaker’s Bureau; Self; AstraZeneca, Novo Nordisk Inc., Sanofi. Other Relationship; Self; Lilly Diabetes, Menarini Group.

© 2020 by the American Diabetes Association
2020
Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered. More information is available at http://www.diabetesjournals.org/content/license.