Genetic Polymorphisms and the Risk of Diabetic Foot: A Systematic Review and Meta-Analyses

Metabolic dysfunction-associated fatty liver disease in the elderly with diabetic foot ulcers: A longitudinal cohort study

This study aimed to explore the association between metabolic-associated fatty liver disease (MAFLD) and ulcer recurrence risk in patients with diabetic foot ulcers (DFUs) through an ambispective longitudinal cohort. From December 2013 to December 2022, a total of 482 inpatients with DFUs (PEDIS grade 3 and above with a severe infection) were eligible for inclusion in this study. This was an ambispective longitudinal cohort study. All participants were followed up every 6 months for 9 years with a median of 36 months. According to whether having MAFLD or not, all subjects were placed into two groups: non-MAFLD (n = 351) and MAFLD (n = 131). The association between MAFLD and ulcer recurrence in patients with DFUs was then evaluated through multivariate Cox regression analysis, stratified analyses and Kaplan-Meier survival analysis. Throughout the follow-up period, out of 482 subjects with DFUs, 68 had ulcer recurrence (14.1%). Three Cox regression models were established for data analyses. In the model I (unadjusted), MAFLD was significantly associated with the ulcer recurrence rate in patients with DFUs (HR = 1.79; 95% CI = 1.097-2.92; p = 0.02). Model II (adjusted model I with gender and age) (HR = 1.781; 95% CI = 1.09-2.912; p = 0.021) and model III (adjusted model II with CVD, duration of diabetes and Cr.) (HR = 1.743; 95% CI = 1.065-2.855; p = 0.027) also showed that MAFLD was significantly related to the ulcer recurrence risk in patients with DFUs, respectively. Stratified analysis indicated that subjects aged ≥60 had a greater risk of ulcer recurrence in MAFLD than in non-MAFLD (HR = 2.31; 95% CI = 1.268-4.206; p = 0.006). Kaplan-Meier survival curve analysis showed that ulcer recurrence rate had a significant association with MAFLD (log-rank, p = 0.018). This study indicated a close association between ulcer recurrence risk and MAFLD in patients with DFUs, especially in the elderly (aged ≥60). Therefore, special attention should be paid to the elderly with both DFUs and MAFLD because they have a higher ulcer recurrence rate than other general populations in routine clinical practice.

Single nucleotide variations in the development of diabetic foot ulcer: A narrative review

Diabetes mellitus has become a global health problem, and the number of patients with diabetic foot ulcers (DFU) is rapidly increasing. Currently, DFU still poses great challenges to physicians, as the treatment is complex, with high risks of infection, recurrence, limb amputation, and even death. Therefore, a comprehensive understanding of DFU pathogenesis is of great importance. In this review, we summarized recent findings regarding the DFU development from the perspective of single-nucleotide variations (SNVs). Studies have shown that SNVs located in the genes encoding C-reactive protein, interleukin-6, tumor necrosis factor-alpha, stromal cell-derived factor-1, vascular endothelial growth factor, nuclear factor erythroid-2-related factor 2, sirtuin 1, intercellular adhesion molecule 1, monocyte chemoattractant protein-1, endothelial nitric oxide synthase, heat shock protein 70, hypoxia inducible factor 1 alpha, lysyl oxidase, intelectin 1, mitogen-activated protein kinase 14, toll-like receptors, osteoprotegerin, vitamin D receptor, and fibrinogen may be associated with the development of DFU. However, considering the limitations of the present investigations, future multi-center studies with larger sample sizes, as well as in-depth mechanistic research are warranted.

Free Triiodothyronine and Free Triiodothyronine to Free Thyroxine Ratio Predict All-Cause Mortality in Patients with Diabetic Foot Ulcers

PURPOSE

Free triiodothyronine (FT3) and FT3/free thyroxine (FT4) ratio have been associated with mortality in various diseases. However, no study to date has identified a link between FT3, FT3/FT4 ratio and all-cause mortality in patients with diabetic foot ulcers (DFUs). This study aimed to investigate this relationship.

METHODS

This retrospective cohort study included 726 patients diagnosed with DFUs in a public hospital from January 2015 to October 2019. Patients were classified by the optimal cut-off values of the FT3 and FT3/FT4 ratio, respectively. The association of FT3 and FT3/FT4 ratio with all-cause mortality was evaluated in a multivariable cox regression model. Directed acyclic graphs were used to assess the minimally sufficient sets of confounding variables.

RESULTS

Log rank tests indicated that patients with low FT3 and FT3/FT4 ratio had lower overall survival rates (all p < 0.001). The adjusted HRs for all-cause mortality were 0.48 (95% CI: 0.32-0.73, P = 0.001) when comparing high versus low FT3 and 0.47 (95% CI: 0.32-0.70, P < 0.001) when comparing high versus low FT3/FT4 ratio. Subgroup analyses showed that these associations existed only in elderly patients (≥65 years) and women, after adjustment. In men, only high FT3/FT4 ratio was associated with low all-cause mortality, after adjustment.

CONCLUSION

Routine assessment of FT3 and FT3/FT4 ratio may be a simple and effective way to identify high-risk patients with DFUs, especially in elderly patients and women.

Enhanced Expression of miR-34c in Peripheral Plasma Associated with Diabetic Foot Ulcer in Type 2 Diabetes Patients

OBJECTIVE

To explore the correlation between the expression of miR-34c in peripheral blood of patients with type 2 diabetes mellitus (T2DM) and the onset of diabetic foot ulcer (DFU) and diabetic foot osteomyelitis (DFO).

METHODS

Sixty newly diagnosed patients with T2DM without DFU (T2DM group), 112 T2DM patients with DFU (DFU group) and 60 controls with normal glucose tolerance (NC group). The DFU group patients were subdivided into DFO (n=64) and NDFO (n=48) groups. Quantitative real-time PCR (qRT-PCR) method was used to determine miR-34c expression levels in the peripheral blood of subjects to analyze the clinical characteristics of DFU and DFO risk factors.

RESULTS

MiR-34c expression level in the T2DM group was marked higher than the NC group [2.99 (1.45-6.22) vs 1.01 (0.89-1.52)] (P < 0.05). However, the expression level of miR-34c in the DFU group was significantly higher than the T2DM group [9.65 (6.15-18.63) vs 2.99 (1.45-6.22)] (P < 0.01). Compared with the NDFO group, the expression level of miR-34c in the DFO group was also obviously increased [13.46 (8.89-19.11) vs 6.02 (5.93-14.72)] (P < 0.01). The expression level of miR-34c in DFU patients was positively correlated with the amputation rate of foot ulcers (P=0.030) and was negatively correlated with the healing rate of foot ulcers after eight weeks (P=0.025). Multifactorial logistic regression analysis showed that increased expression of miR-34c was an independent risk factor for DFU and DFO (OR_DFU=3.47, OR_DFO=4.25, P < 0.01). Meanwhile, the ROC curve analysis indicated that the AUC of miR-34c for the diagnosis of DFU and DFO was 0.803 and 0.904, the optimum sensitivity being was 100% and 98.7%, the optimum specificity was 98.4% and 98.4%, respectively.

CONCLUSION

The increased expression of miR-34c in peripheral blood of T2DM patients is closely related to the occurrence, development and prognosis of DFU and DFO.