[Diabetic foot syndrome-Part 1 : Definition, pathophysiology, diagnostics and classification]

Predictors of post-healing recurrence in patients with diabetic foot ulcers: A systematic review and meta-analysis

BACKGROUND

Diabetic foot ulcer is one of the most prevalent, serious, and costly consequences of diabetes, often associated with peripheral neuropathy and peripheral arterial disease. These ulcers contribute to high disability and mortality rates in patients and pose a major challenge to clinical management.

OBJECTIVE

To systematically review the risk prediction models for post-healing recurrence in diabetic foot ulcer (DFU) patients, so as to provide a reference for clinical staff to choose appropriate prediction models.

METHODS

The authors searched five databases (Cochrane Library, PubMed, Web of Science, EMBASE, and Chinese Biomedical Database) from their inception to September 23, 2023, for relevant literature. After data extraction, the quality of the literature was evaluated using the Predictive Model Research Bias Risk and Suitability Assessment tool (PROBAST). Meta-analysis was performed using STATA 17.0 software.

RESULTS

A total of 9 studies involving 5956 patients were included. The recurrence rate after DFU healing ranged from 6.2 % to 41.4 %. Nine studies established 15 risk prediction models, and the area under the curve (AUC) ranged from 0.660 to 0.940, of which 12 models had an AUC≥0.7, indicating good prediction performance. The combined AUC value of the 9 validation models was 0.83 (95 % confidence interval: 0.79-0.88). Hosmer-Lemeshow test was performed for 10 models, external validation for 5 models, and internal validation for 6 models. Meta-analysis showed that 14 predictors, such as age and living alone, could predict post-healing recurrence in DFU patients (p < 0.05).

CONCLUSION

To enhance the quality of these risk prediction models, there is potential for future improvements in terms of follow-up duration, model calibration, and validation processes.

[Topicality of the fundamental and determining importance of chronic critical ischemia of the extremities and its restorative treatment using crural/pedal bypasses in Germany and in Saxony-Anhalt]

INTRODUCTION

Currently, there is an increase in severe stages of peripheral arterial occlusive disease (PAOD) with critical ischemia. This seems to correspond to the general demographic change as well as a consequence of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic of the last 3 years. The now established and accepted interventional/endovascular approach for severe lower leg PAOD in experienced hands is still considered the first-line treatment but from the authors' perspective crural/pedal venous bypass is experiencing a renaissance.

MATERIAL AND METHODS

Compact narrative review of the current state of crural/pedal bypass surgery in Germany and Saxony-Anhalt (SA) combined with selective references from the current scientific medical literature and own clinical experiences.

RESULTS

The current statistics of case-related diagnosis-related groups (DRG) data show that, especially with the occurrence of the corona pandemic, a decrease in inpatient case numbers of patients with PAOD stage IIB can be observed nationwide and also in SA. The severe PAOD stages have remained approximately the same in case numbers but increased in SA. The risk stratification based on the wound, ischemia and foot infection (WIFI) classification offers the possibility to be able to make statements about the risk of amputation, benefits and type of revascularization measures. The length of the occlusion, occlusion site of the affected vessels and degree of calcification are taken into account in the global limb anatomic staging system (GLASS) to assess the prognosis. The evaluation of the case-based hospital statistics from 2015 to 2020 showed a constant use of femorocrural/femoropedal bypass surgery in Germany as well as a slight increase in reconstruction using femorocrural bypasses in SA, which seems to correlate with the tendency for an increase in the number of cases of severe PAOD. Parameter-based objectification of the severity of critical limb ischemia should be included in the indications for placement of a crural/pedal bypass. The WIFI classification and GLASS are suitable for this purpose as a relative prognosis of success is also possible. The treatment of critical limb ischemia by crural/pedal bypass surgery continues to find a constant application in Germany and SA.

Risk Factors for Failure After Surgery in Patients With Diabetic Foot Syndrome

Background

In the present study, we aimed to identify risk factors for failure (defined as reoperation within 60 days) after debridement or amputation at the lower extremity in patients with diabetic foot syndrome and to develop a model using the significant risk factors to predict the success rate at different levels of amputation.

Methods

Between September 2012 and November 2016, we performed a prospective observational cohort study of 174 surgeries in 105 patients with diabetic foot syndrome. In all patients, debridement or the level of amputation, need for reoperation, time to reoperation, and potential risk factors were assessed. A cox regression analysis, dependent on the level of amputation, with the endpoint reoperation within 60 days defined as failure and a predictive model for the significant risk factors were conducted.

Results

We identified the following 5 independent risk factors: More than 1 ulcer (hazard ratio [HR] 3.8), peripheral artery disease (PAD, HR 3.1), C-reactive protein >100 mg/L (HR 2.9), diabetic peripheral neuropathy (HR 2.9), and nonpalpable foot pulses (HR 2.7) are the 5 independent risk factors for failure, which were identified. Patients with no or 1 risk factor have a high success rate independent of the level of amputation. A patient with up to 2 risk factors undergoing debridement will achieve a success rate of <60%. However, a patient with 3 risk factors undergoing debridement will need further surgery in >80%. In patients with 4 risk factors a transmetatarsal amputation and in patients with 5 risk factors a lower leg amputation is needed for a success rate >50%.

Conclusion

Reoperation for diabetic foot syndrome occurs in 1 of 4 patients. Risk factors include presence of more than 1 ulcer, PAD, CRP > 100, peripheral neuropathy, and nonpalpable foot pulses. The more risk factors are present, the lower the success rate at a certain level of amputation.

Level of Evidence

Level II, prospective observational cohort study.

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.

Development of predictive nomograms clinical use to quantify the risk of diabetic foot in patients with type 2 diabetes mellitus

Objective

The aim of the study was to explore the risk factors for diabetic foot disease in patients with type 2 diabetes mellitus and to establish and verify the nomogram model of DF risk in patients with T2DM.

Methods

The clinical data of 705 patients with type 2 diabetes who were hospitalized in our hospital from January 2015 to December 2022 were analyzed retrospectively. According to random sampling, the patients were divided into two groups: the training set (DF = 84; simple T2DM = 410) and the verification set (DF = 41; simple T2DM = 170). Univariate and multivariate logistic regression analysis was used to screen the independent risk factors for DF in patients with T2DM in the training set. According to the independent risk factors, the nomogram risk prediction model is established and verified.

Results

Logistic regression analysis showed age (OR = 1.093, 95% CI 1.062-1.124, P <0.001), smoking history (OR = 3.309, 95% CI 1.849-5.924, P <0.001), glycosylated hemoglobin (OR = 1.328, 95% CI 1.173-1.502, P <0.001), leukocyte (OR = 1.203, 95% CI 1.076-1.345, and LDL-C (OR = 2.002, 95% CI 1.463-2.740), P <0.001) was independent risk factors for T2DM complicated with DF. The area of the nomogram model based on the above indexes under the ROC curve of the training set and the verification set is 0.827 and 0.808, respectively; the correction curve shows that the model has good accuracy; and the DCA results show that when the risk threshold is between 0.10-0.85 (training set) and 0.10-0.75 (verification set), the clinical practical value of the model is higher.

Conclusion

The nomogram model constructed in this study is of high value in predicting the risk of DF in patients with T2DM and is of reference value for clinicians to identify people at high risk of DF and provide them with early diagnosis and individual prevention.

The Interdisciplinary Approach: Preventive and Therapeutic Strategies for Diabetic Foot Ulcers

The appropriate treatment of the common diabetic foot ulcers (DFUs) in diabetic patients demands enormous human, organizational and financial resources that are finite. Interdisciplinary teams of medical and surgical specialists, as well as allied health professionals, can help to reduce the consumption of these resources, optimize treatment, and prevent DFUs. They consist primarily of vascular surgeons, endocrinologists, and orthopedic foot and ankle surgeons and are closely supported when required by infectious diseases specialists, plastic surgeons, wound care specialist nurses, podiatrists, and orthotists. A timely interdisciplinary team review in each clinic session decreases the number of hospital visits for the oftentimes-handicapped diabetic patients significantly. The interdisciplinary team clinic setup has also been shown to reduce the risk of amputations, length of hospital staz and mortality rates.

[Diabetic foot syndrome-Part 2 : Revascularization, treatment alternatives, care structures, recurrency prophylaxis]

Diabetic foot syndrome (DFS) is the most frequent reason for major amputations in Germany. The majority of foot lesions are triggered by repetitive pressure in diabetic polyneuropathy. Peripheral arterial occlusive disease (PAOD) impairs wound healing and is the main risk factor for amputations. The treatment of wounds and infections as well as timely revascularization are decisive. The use of endovascular and vascular surgical methods depends on the distribution pattern and length of the occlusion processes. Both procedures are complementary. Bypass surgery is of great importance for neuroischemic DFS. Multidisciplinary centers that provide revascularization in DFS can achieve an improvement of arterial blood flow in 90% of the cases and reduce the amputation rate by up to 80%. Due to the high recurrence rate of diabetic foot lesions, measures for secondary prophylaxis are of exceptional importance (podological and orthopedic technical care, foot surgery).