Diabetic Foot Ulcers and Vitamin D Status: A Literature Review

Correlation between initial serum 25-hydroxyvitamin D and granulation growth in diabetic foot ulcers

OBJECTIVE

To determine the correlation between initial serum 25-hydroxyvitamin D (25(OH)D) levels with granulation growth in diabetic foot ulcers (DFUs) after 21 days of treatment.

METHOD

This cohort study involved patients with type 2 diabetes who had a DFU treated at hospital. Blood samples were taken from patients on admission. The chemiluminescent immunoassay technique was used to measure 25(OH)D levels. Granulation tissue growth was analysed by comparing the photographs from the initial treatment to day 21 of treatment.

RESULTS

The median value of 25(OH)D levels at initial treatment was 8 ng/ml. The result showed no correlation between 25(OH)D levels and the granulation growth in DFUs (p=0.86).

CONCLUSION

The initial serum 25(OH)D level was not correlated with the growth of granulation tissue in DFUs.

RETRACTED: Analysis of the association between serum levels of 25(OH)D, retinol binding protein, and Cyclooxygenase-2 and the disease severity in patients with diabetic foot ulcers

Diabetic foot ulcers (DFUs) pose significant clinical challenges, representing severe complications in diabetes mellitus patients and contributing to non-traumatic amputations. Identifying reliable biomarkers can optimize early diagnosis and improve therapeutic outcomes. This study focused on evaluating the association between serum levels of 25-hydroxyvitamin D [25-(OH)D], Serum Retinol Binding Protein (RBP), and Cyclooxygenase-2 (COX-2) in elderly DFU patients. A retrospective study involving 240 participants, from March 2020 to March 2023. The participants were segmented into three cohorts: 80 with DFUs, 80 diabetic patients without DFUs, and 80 healthy controls. Serum concentrations of the three biomarkers were assayed using methods like enzyme-linked immunosorbent assay (ELISA), chemiluminescence immunoassay, and an automated biochemistry analyser. Comparisons were made both between groups and within the DFU group based on disease severity. Statistical analysis revealed significant differences in biomarker levels across the groups (p < 0.05). COX-2 and RBP concentrations were highest in the DFU group, followed by the non-DFU diabetic group, and lowest in the control group. Conversely, 25(OH)D levels were highest in the control group, followed by the non-DFU diabetic group, and lowest in the DFU group. Within the DFU group, RBP and COX-2 levels increased with disease severity, while 25(OH)D levels decreased. These variations were especially pronounced in patients with the most severe Wagner grading. A significant positive correlation was observed between disease severity and levels of RBP (r = 0.651, p < 0.05) and COX-2 (r = 0.356, p < 0.05). Conversely, a significant negative correlation was identified between disease severity and 25(OH)D levels (r = -0.658, p < 0.05). Assessing 25(OH)D, RBP, and COX-2 serum levels offers a promising tool for evaluating the severity and progression of DFUs. Monitoring these biomarkers can enrich our understanding of the metabolic and inflammatory pathways of the disease and potentially refine therapeutic strategies.

Vitamin D deficiency among outpatients and hospitalized patients with diabetic foot ulcers: A systematic review and meta-analysis

BACKGROUND

The definition of diabetic foot syndrome (DFS) varies depending on the location and resources. Few classifications are available according to the indication. DF ulcers and vitamin D deficiency are common diseases among patients with diabetes. Previous literature has shown an association between DF ulcer (DFU) and vitamin D deficiency. However, the available meta-0analysis was limited by substantial bias.

AIM

To investigate the association between DFUs and vitamin D levels.

METHODS

We searched PubMed, MEDLINE, and Cochrane Library, EBSCO, and Google Scholar for studies comparing vitamin D levels and DF. The keywords DFU, DFS, diabetic septic foot, vitamin D level, 25-hydroxy vitamin D, vitamin D status, and vitamin D deficiency were used. The search engine was set for articles published during the period from inception to October 2022. A predetermined table was used to collect the study information.

RESULTS

Vitamin D level was lower among patients with DFU compared to their counterparts [odds ratio (OR): -5.77; 95% confidence interval (CI): -7.87 to -3.66; χ² was 84.62, mean difference, 9; I² for heterogeneity, 89%; P < 0.001 and P for overall effect < 0.001]. The results remained robust for hospitalized patients (OR: -6.32 95%CI: -11.66 to -0.97; χ² was 19.39; mean difference, 2; I² for heterogeneity, 90%; P = 0.02).

CONCLUSION

Vitamin D was lower among outpatients and hospitalized patients with DFUs. Further larger randomized controlled trials are needed.

The effects of dietary/herbal supplements and the serum levels of micronutrients on the healing of diabetic foot ulcers in animal and human models: a systematic review

PURPOSE

Diabetic Foot Ulcer (DFU) is one of the common and serious complications in patients with Diabetes Mellitus (DM) worldwide. Given the considerable tendency of patients suffering from DFU to use the complementary therapies, the objectives of this study were to: (i) summarize the effects of dietary and herbal supplements on DFU characteristics and metabolic parameters in both animal models and clinical trials, and (ii) evaluate any links between the serum levels of micronutrients and DFU in observational studies.

METHODS

A systematic search in five electronic databases including PubMed/Medline, Scopus, Web of Science, Embase, and Cochrane Library was conducted to find relevant English language published from 1990 until 31 December 2018.

RESULTS

Of a total of 8603 studies, 30 eligible papers including animal studies (n = 15), clinical trials (n = 7), and observational works (n = 8) were included in the systematic review. We found that some dietary/herbal supplements and micronutrients had positive effects on the wound healing. However, limited evidence is existed. Also, lower serum levels of vitamin D, C, vitamin E, and selenium in patients with DFU were likely to increase the risk of DFU, leading to impaired wound healing.

CONCLUSION

Findings suggested that some dietary and herbal supplements such as Vitamin D, Magnesium, Vitamin E, Probiotic, Zinc, and Pycnogenol would be effective on wound healing of DFUs. However, further high-quality randomized controlled clinical trials and prospective cohort studies are needed to clarify the roles of micronutrients and other dietary and herbal supplements on the progress and treatment of DFU.

Vitamin D Supplementation in Diabetic Foot Ulcers: A Current Perspective

INTRODUCTION

Diabetic foot ulcer (DFU) is a major complication of diabetes mellitus, as it can physically and emotionally impact the person. Its management can be challenging and expensive, depending on the severity of the wound and the presence of infection.

BACKGROUND

The fat-soluble molecule, vitamin D, has gained great importance ever since its pleiotropism has been recognized. Its efficacy could be attributed to the presence of vitamin D receptors in most of the body tissues. Vitamin D plays a significant role in cell proliferation, differentiation, and immune modulation. It modulates the T and B cells resulting in the suppression of the immunoglobulins, autoimmunity, and inflammation.

METHODS

We performed a literature search with the objective to highlight the role of vitamin D in peripheral vascular disease and peripheral neuropathy, which are the major risk factors for DFU, as well as evidences of its role in wound healing and management of DFU.

RESULTS

Preclinical and clinical studies have shown that vitamin D influences multiple phases of wound healing and thereby accelerates the process. It modulates various cells involved in proliferation and remodelling phases. Vitamin D also enhances the expression of antimicrobial peptides that help to eliminate the microbes, as well as suppress the proinflammatory responses while enhancing the anti-inflammatory responses.

CONCLUSION

This review concludes vitamin D to have a protective role in the immune and vascular system, improve glycaemic outcomes, and wound healing. Therefore, vitamin D could be a preferred adjuvant in the management of DFU.

Vitamin D and the athlete-patient: state of the art

Vitamin D deficiency is common in athletes. The conventional measurement of vitamin D levels provides a general indicator of body stores. However, there are nuances in its interpretation as values of 25(OH)D do not correlate absolutely with the amount of 'bioavailable' vitamin to the cells. Vitamin D should be regarded as a hormone and influences between 5% and 10% of our total genome. Determining the precise effect of the vitamin, isolated from the actions of other cofactors, is not straightforward and restricts our complete understanding of all of its actions. Deficiency has harmful effects on not only bone and muscle but also wider areas, including immunity and respiratory and neurological activities. More caution should be applied regarding the ability of supranormal vitamin D levels to elevate athletic performance. Hopefully, future research will shed more light on optimal levels of vitamin D and supplementation regimes, and improved understanding of its intracellular control of our genetic mechanisms and how extrinsic influences modify its activity.