Diabetic foot ulcers—comparison of performance of ankle-brachial index and transcutaneous partial oxygen pressure in predicting outcome

Current Opinion on Diagnosis of Peripheral Artery Disease in Diabetic Patients

Peripheral arterial disease (PAD) prevalence and diabetes mellitus (DM) prevalence are continuously increasing worldwide. The strong relationship between DM and PAD is highlighted by recent evidence. PAD diagnosis in diabetic patients is very important, particularly in patients with diabetic foot disease (DFD); however, it is often made difficult by the characteristics of such diseases. Diagnosing PAD makes it possible to identify patients at a very high cardiovascular risk who require intensive treatment in terms of risk factor modification and medical therapy. The purpose of this review is to discuss the diagnostic methods that allow for a diagnosis of PAD in diabetic patients. Non-invasive tests that address PAD diagnosis will be discussed, such as the ankle-brachial index (ABI), toe pressure (TP), and transcutaneous oxygen pressure (TcPO2). Furthermore, imaging methods, such as duplex ultrasound (DUS), computed tomography angiography (CTA), magnetic resonance angiography (MRA), and digital subtraction angiography (DSA), are described because they allow for diagnosing the anatomical localization and severity of artery stenosis or occlusion in PAD. Non-invasive tests will also be discussed in terms of their ability to assess foot perfusion. Foot perfusion assessment is crucial in the diagnosis of critical limb ischemia (CLI), the most advanced PAD stage, particularly in DFD patients. The impacts of PAD diagnosis and CLI identification in diabetic patients are clinically relevant to prevent amputation and mortality.

The intersocietal IWGDF, ESVS, SVS guidelines on peripheral artery disease in people with diabetes mellitus and a foot ulcer

Diabetes related foot complications have become a major cause of morbidity and are implicated in most major and minor amputations globally. Approximately 50% of people with diabetes and a foot ulcer have peripheral artery disease (PAD) and the presence of PAD significantly increases the risk of adverse limb and cardiovascular events. The International Working Group on the Diabetic Foot (IWGDF) has published evidence based guidelines on the management and prevention of diabetes related foot complications since 1999. This guideline is an update of the 2019 IWGDF guideline on the diagnosis, prognosis, and management of peripheral artery disease in people with diabetes mellitus and a foot ulcer. For this updated guideline, the IWGDF, the European Society for Vascular Surgery, and the Society for Vascular Surgery decided to collaborate to develop a consistent suite of recommendations relevant to clinicians in all countries. This guideline is based on three new systematic reviews. Using the Grading of Recommendations, Assessment, Development and Evaluation framework clinically relevant questions were formulated, and the literature was systematically reviewed. After assessing the certainty of the evidence, recommendations were formulated which were weighed against the balance of benefits and harms, patient values, feasibility, acceptability, equity, resources required, and when available, costs. Through this process five recommendations were developed for diagnosing PAD in a person with diabetes, with and without a foot ulcer or gangrene. Five recommendations were developed for prognosis relating to estimating likelihood of healing and amputation outcomes in a person with diabetes and a foot ulcer or gangrene. Fifteen recommendations were developed related to PAD treatment encompassing prioritisation of people for revascularisation, the choice of a procedure and post-surgical care. In addition, the Writing Committee has highlighted key research questions where current evidence is lacking. The Writing Committee believes that following these recommendations will help healthcare professionals to provide better care and will reduce the burden of diabetes related foot complications.

The Intersocietal IWGDF, ESVS, SVS Guidelines on Peripheral Artery Disease in People With Diabetes Mellitus and a Foot Ulcer

Diabetes related foot complications have become a major cause of morbidity and are implicated in most major and minor amputations globally. Approximately 50% of people with diabetes and a foot ulcer have peripheral artery disease (PAD) and the presence of PAD significantly increases the risk of adverse limb and cardiovascular events. The International Working Group on the Diabetic Foot (IWGDF) has published evidence based guidelines on the management and prevention of diabetes related foot complications since 1999. This guideline is an update of the 2019 IWGDF guideline on the diagnosis, prognosis, and management of peripheral artery disease in people with diabetes mellitus and a foot ulcer. For this updated guideline, the IWGDF, the European Society for Vascular Surgery, and the Society for Vascular Surgery decided to collaborate to develop a consistent suite of recommendations relevant to clinicians in all countries. This guideline is based on three new systematic reviews. Using the Grading of Recommendations, Assessment, Development and Evaluation framework clinically relevant questions were formulated, and the literature was systematically reviewed. After assessing the certainty of the evidence, recommendations were formulated which were weighed against the balance of benefits and harms, patient values, feasibility, acceptability, equity, resources required, and when available, costs. Through this process five recommendations were developed for diagnosing PAD in a person with diabetes, with and without a foot ulcer or gangrene. Five recommendations were developed for prognosis relating to estimating likelihood of healing and amputation outcomes in a person with diabetes and a foot ulcer or gangrene. Fifteen recommendations were developed related to PAD treatment encompassing prioritisation of people for revascularisation, the choice of a procedure and post-surgical care. In addition, the Writing Committee has highlighted key research questions where current evidence is lacking. The Writing Committee believes that following these recommendations will help healthcare professionals to provide better care and will reduce the burden of diabetes related foot complications.

The Association between Foot and Ulcer Microcirculation Measured with Laser Speckle Contrast Imaging and Healing of Diabetic Foot Ulcers

Diagnosis of peripheral artery disease in people with diabetes and a foot ulcer using current non-invasive blood pressure measurements is challenging. Laser speckle contrast imaging (LSCI) is a promising non-invasive technique to measure cutaneous microcirculation. This study investigated the association between microcirculation (measured with both LSCI and non-invasive blood pressure measurement) and healing of diabetic foot ulcers 12 and 26 weeks after measurement. We included sixty-one patients with a diabetic foot ulcer in this prospective, single-center, observational cohort-study. LSCI scans of the foot, ulcer, and ulcer edge were conducted, during baseline and post-occlusion hyperemia. Non-invasive blood pressure measurement included arm, foot, and toe pressures and associated indices. Healing was defined as complete re-epithelialization and scored at 12 and 26 weeks. We found no significant difference between patients with healed or non-healed foot ulcers for both types of measurements (p = 0.135-0.989). ROC curves demonstrated moderate sensitivity (range of 0.636-0.971) and specificity (range of 0.464-0.889), for LSCI and non-invasive blood pressure measurements. Therefore, no association between diabetic foot ulcer healing and LSCI-measured microcirculation or non-invasive blood pressure measurements was found. The healing tendency of diabetic foot ulcers is difficult to predict based on single measurements using current blood pressure measurements or LSCI.

Characteristics and Outcomes of Patients With Diabetes Mellitus Undergoing Peripheral Vascular Intervention for Infrainguinal Symptomatic Peripheral Artery Disease

PURPOSE

Patients with diabetes mellitus (DM) are known to be at higher risk for peripheral artery disease (PAD), amputations, and major adverse cardiovascular events, though it is unclear whether they are at any higher risk for repeat intervention. LIBERTY 360 offered an opportunity to study a real-world cohort of patients who underwent distal superficial femoral artery endovascular revascularizations. We aimed to describe patients with DM, their outcomes following peripheral vascular intervention, and the effect of DM on outcomes in the LIBERTY 360 cohort.

METHODS

LIBERTY 360 is a prospective, multi-center, non-randomized, mono-industry funded observational study of patients undergoing endovascular revascularization. Outcomes included 30-day and 1-year all-cause mortality, major amputation, target vessel/lesion revascularization, and a composite of those events. A multivariable regression model including DM was constructed to examine the effect of DM on outcomes. Multivariable survival estimates were made using Cox proportional hazards models.

RESULTS

A total of 1,204 patients were enrolled, of whom 727 had DM (60.4%). Patients with DM had significantly more comorbidities and a third required insulin for DM management. Patients with DM had more severe disease based on Rutherford classification at baseline. After adjusting for comorbidities and disease severity, DM patients had more frequent major amputations at 1 year (5.2% versus 1.2%; HR 2.71, 95%CI 1.05-6.98, p = 0.040). The 1-year rates of all-cause mortality and target vessel/lesion revascularization were not significantly higher for patients with DM.

CONCLUSIONS

Diabetes mellitus was associated with increased major amputations at 1 year following endovascular revascularization after accounting for demographics, comorbidities, and PAD-related characteristics. Further research is needed to determine which aspects of PAD and DM are most strongly associated with poor outcomes following lower extremity revascularization.