Guidelines on diagnosis, prognosis, and management of peripheral artery disease in patients with foot ulcers and diabetes (IWGDF 2019 update)

The International Working Group on the Diabetic Foot (IWGDF) has published evidence-based guidelines on the prevention and management of diabetic foot disease since 1999. This guideline is on the diagnosis, prognosis, and management of peripheral artery disease (PAD) in patients with foot ulcers and diabetes and updates the previous IWGDF Guideline. Up to 50% of patients with diabetes and foot ulceration have concurrent PAD, which confers a significantly elevated risk of adverse limb events and cardiovascular disease. We know that the diagnosis, prognosis, and treatment of these patients are markedly different to patients with diabetes who do not have PAD and yet there are few good quality studies addressing this important subset of patients. We followed the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) methodology to devise clinical questions and critically important outcomes in the patient-intervention-comparison-outcome (PICO) format, to conduct a systematic review of the medical-scientific literature, and to write recommendations and their rationale. The recommendations are based on the quality of evidence found in the systematic review, expert opinion where evidence was not available, and a weighing of the benefits and harms, patient preferences, feasibility and applicability, and costs related to the intervention. We here present the updated 2019 guidelines on diagnosis, prognosis, and management of PAD in patients with a foot ulcer and diabetes, and we suggest some key future topics of particular research interest.

Effectiveness of revascularisation of the ulcerated foot in patients with diabetes and peripheral artery disease: A systematic review

In patients with diabetes, foot ulceration and peripheral artery disease (PAD), it is often difficult to determine whether, when and how to revascularise the affected lower extremity. The presence of PAD is a major risk factor for non-healing and yet clinical outcomes of revascularisation are not necessarily related to technical success. The International Working Group of the Diabetic Foot updated systematic review on the effectiveness of revascularisation of the ulcerated foot in patients with diabetes and PAD is comprised of 64 studies describing >13 000 patients. Amongst 60 case series and 4 non-randomised controlled studies, we summarised clinically relevant outcomes and found them to be broadly similar between patients treated with open vs endovascular therapy. Following endovascular revascularisation, the 1 year and 2 year limb salvage rates were 80% (IQR 78-82%) and 78% (IQR 75-83%), whereas open therapy was associated with rates of 85% (IQR 80-90%) at 1 year and 87% (IQR 85-88%) at 2 years, however these results were based on a varying combination of studies and cannot therefore be interpreted as cumulative. Overall, wound healing was achieved in a median of 60% of patients (IQR 50-69%) at 1 year in those treated by endovascular or surgical therapy, and the major amputation rate of endovascular vs open therapy was 2% vs 5% at 30 days, 10% vs 9% at 1 year and 13% vs 9% at 2 years. For both strategies, overall mortality was found to be high, with 2% (1-6%) perioperative (or 30 day) mortality, rising sharply to 13% (9-23%) at 1 year, 29% (19-48%) at 2 years and 47% (39-71%) at 5 years. Both the angiosome concept (revascularisation directly to the area of tissue loss via its main feeding artery) or indirect revascularisation through collaterals, appear to be equally effective strategies for restoring perfusion. Overall, the available data do not allow us to recommend one method of revascularisation over the other and more studies are required to determine the best revascularisation approach in diabetic foot ulceration.

The patient presenting with chronic limb-threatening ischaemia. Does diabetes influence presentation, limb outcomes and survival?

Peripheral arterial disease (PAD) confers an elevated risk of major amputation and delayed wound healing in diabetic patients with foot ulcers. The major international vascular societies recently developed evidence-based guidelines for the assessment and management of patients with chronic limb-threatening ischaemia (CLTI). CLTI represents the cohort of diabetic and non-diabetic patients who have PAD which is of sufficient severity to delay wound healing and increase amputation risk. Diabetic patients with CLTI are more likely to present with tissue loss, infection and have less favourable anatomy for revascularization than those without diabetes. Although diabetes is not consistently reported as a strong independent risk factor for limb loss, major morbidity and mortality in CLTI patients, it is impossible in clinical practice to isolate diabetes from comorbidities, such as end-stage renal disease and coronary artery disease which occur more commonly in diabetic patients. Treatment of CLTI in the diabetic patient is complex and should involve a multi-disciplinary team to optimize outcomes. Clinicians should use an integrated approach to management based on patient risk assessment, an assessment of the severity of the foot pathology and a structured anatomical assessment of arterial disease as suggested by the Global Vascular Guidelines for CLTI.

Mental health concerns in patients with symptomatic peripheral artery disease: Insights from the PORTRAIT registry

OBJECTIVES

To document the prevalence and patient profiles of mental health concerns in patients with peripheral artery disease (PAD) seen in the vascular specialty setting.

METHODS

In a cohort of 1275 patients presenting to 16 specialty clinics with new or worsening claudication, symptoms of depression, anxiety, and stress were quantified in 957 patients. The Patient Health Questionnaire-8 (PHQ-8), Generalized Anxiety Disorder scale-2 (GAD-2), and Perceived Stress Scale-4 (PSS-4) were assessed for mental health concerns at the initial PAD work-up and repeated 12 months later. PHQ-8 ≥ 10, GAD-2 ≥ 3 and PSS-4 ≥ 6 were considered significant for depression, anxiety and stress respectively. Patient characteristics were compared in groups divided by presence of 0, 1, 2 or all 3 mental health concerns.

RESULTS

On the initial office visit, 336/957 (35%) of patients had high levels of at least one of the three mental health concerns. At both baseline and 12 months, high levels of perceived stress were most often reported (28.7% and 17.5% respectively), followed by symptoms of depression (14.1% and 8.9%) and then anxiety (8.3% and 5.7%). Patients with mental health concerns were more often female, younger, had more financial strain, less social support, and worse perceived health status.

CONCLUSIONS

Mental health concerns, particularly stress, are highly prevalent in patients with PAD, especially upon first presenting with new or worsening symptoms. The role of stress and how it may impede successful PAD management and impact subsequent outcomes warrants further investigation.

Adherence to Guideline-Recommended Therapy-Including Supervised Exercise Therapy Referral-Across Peripheral Artery Disease Specialty Clinics: Insights From the International PORTRAIT Registry

Background

Underuse of guideline‐recommended therapy in peripheral artery disease (PAD) in administrative and procedural databases has been described, but reports on medically managed patients and referral to supervised exercise therapy (SET) in PAD are lacking. We aimed to document the use of PAD guideline‐recommended therapy, including SET in patients with PAD symptoms consulting a specialty clinic across 3 countries.

Methods and Results

The 16‐center PORTRAIT (Patient‐Centered Outcomes Related to Treatment Practices in Peripheral Arterial Disease: Investigating Trajectories) registry enrolled 1275 patients with new or an exacerbation of PAD symptoms (2011–2015). We prospectively documented antiplatelet medications, statins, smoking cessation counseling and/or therapy, and referral to SET: “2 quality measures” referred to the use of both statin and antiplatelet medications; “4 quality measures” to receiving all 4 measures. Median odds ratios were calculated to quantify treatment variation across sites. A total of 89% patients were on antiplatelets, 83% on statins, and 23% had been referred to SET. Of 455 current smokers, 342 (72%) patients received smoking cessation therapy/counseling. Overall, 77.2% of patients received “2 quality measures” and 19.7% “4 quality measures.” The median odds ratio for 2 quality measures was 2.13 (95% CI, 1.61–3.56; P<0.001) and for 4 quality measures was 5.43 (95% CI, 2.84–17.91; P<0.001). Variability in adherence was not explained by country, except for referral to SET. The odds for SET referral in The Netherlands (70% referral rate) was nearly 100 times greater than in US sites (2% referral rate).

Conclusions

Not all patients who have undergone a PAD workup at a specialty care facility are treated with evidence‐based care, especially so for SET.

Micronutrient Status in Diabetic Patients with Foot Ulcers

Objective: To explore the prevalence of micronutrient deficiencies in patients with diabetic foot ulcers and correlate this with foot disease severity and other clinical factors. Approach: Prospective cohort study of diabetic patients with foot ulcers seen in multidisciplinary foot clinics across Adelaide or admitted to the Vascular Surgery Unit at the Royal Adelaide Hospital between February 2017 and September 2018. A total of 131 patients were included in the study. Plasma serum levels of vitamins A, C, D, and E, copper, zinc, and ferritin were measured. Demographic and clinical data, including BMI, smoking status, duration of diabetes, HbA1c, and WIfI score, were obtained. Results: The most prevalent nutritional deficiency found was vitamin D affecting 55.7% of patients. Suboptimal levels of vitamin C affected 73% of patients, comprising marginal levels in 22.2% and deficient levels in 50.8%. Zinc deficiency, vitamin A deficiency, and low ferritin levels were present in 26.9%, 10.9%, and 5.9% of patients, respectively. There was no correlation between BMI, grip strength, duration of diabetes, HbA1c, or smoking status with micronutrient deficiency. Increased severity of diabetic foot disease was associated with lower vitamin C levels (p = 0.02). Innovation: This study has demonstrated that the deficiency of micronutrients, especially vitamin D, vitamin C, zinc, and vitamin A, is common in diabetic patients with foot ulcers. Conclusions: The prevalence of micronutrient deficiency is high in a diabetic population with foot ulcers/wounds. Special concerns regarding the high prevalence of vitamin C and zinc deficiency, given their roles in wound healing. Although further research needs to be performed to determine the clinical implications of our findings, micronutrient deficiency should be considered in diabetic patients with foot wounds.

Global Vascular Guidelines on the Management of Chronic Limb-Threatening Ischemia

GUIDELINE SUMMARY

Chronic limb-threatening ischemia (CLTI) is associated with mortality, amputation, and impaired quality of life. These Global Vascular Guidelines (GVG) are focused on definition, evaluation, and management of CLTI with the goals of improving evidence-based care and highlighting critical research needs. The term CLTI is preferred over critical limb ischemia, as the latter implies threshold values of impaired perfusion rather than a continuum. CLTI is a clinical syndrome defined by the presence of peripheral artery disease (PAD) in combination with rest pain, gangrene, or a lower limb ulceration >2 weeks duration. Venous, traumatic, embolic, and nonatherosclerotic etiologies are excluded. All patients with suspected CLTI should be referred urgently to a vascular specialist. Accurately staging the severity of limb threat is fundamental, and the Society for Vascular Surgery Threatened Limb Classification system, based on grading of Wounds, Ischemia, and foot Infection (WIfI) is endorsed. Objective hemodynamic testing, including toe pressures as the preferred measure, is required to assess CLTI. Evidence-based revascularization (EBR) hinges on three independent axes: Patient risk, Limb severity, and ANatomic complexity (PLAN). Average-risk and high-risk patients are defined by estimated procedural and 2-year all-cause mortality. The GVG proposes a new Global Anatomic Staging System (GLASS), which involves defining a preferred target artery path (TAP) and then estimating limb-based patency (LBP), resulting in three stages of complexity for intervention. The optimal revascularization strategy is also influenced by the availability of autogenous vein for open bypass surgery. Recommendations for EBR are based on best available data, pending level 1 evidence from ongoing trials. Vein bypass may be preferred for average-risk patients with advanced limb threat and high complexity disease, while those with less complex anatomy, intermediate severity limb threat, or high patient risk may be favored for endovascular intervention. All patients with CLTI should be afforded best medical therapy including the use of antithrombotic, lipid-lowering, antihypertensive, and glycemic control agents, as well as counseling on smoking cessation, diet, exercise, and preventive foot care. Following EBR, long-term limb surveillance is advised. The effectiveness of nonrevascularization therapies (eg, spinal stimulation, pneumatic compression, prostanoids, and hyperbaric oxygen) has not been established. Regenerative medicine approaches (eg, cell, gene therapies) for CLTI should be restricted to rigorously conducted randomizsed clinical trials. The GVG promotes standardization of study designs and end points for clinical trials in CLTI. The importance of multidisciplinary teams and centers of excellence for amputation prevention is stressed as a key health system initiative.

Global vascular guidelines on the management of chronic limb-threatening ischemia

Chronic limb-threatening ischemia (CLTI) is associated with mortality, amputation, and impaired quality of life. These Global Vascular Guidelines (GVG) are focused on definition, evaluation, and management of CLTI with the goals of improving evidence-based care and highlighting critical research needs. The term CLTI is preferred over critical limb ischemia, as the latter implies threshold values of impaired perfusion rather than a continuum. CLTI is a clinical syndrome defined by the presence of peripheral artery disease (PAD) in combination with rest pain, gangrene, or a lower limb ulceration >2 weeks duration. Venous, traumatic, embolic, and nonatherosclerotic etiologies are excluded. All patients with suspected CLTI should be referred urgently to a vascular specialist. Accurately staging the severity of limb threat is fundamental, and the Society for Vascular Surgery Threatened Limb Classification system, based on grading of Wounds, Ischemia, and foot Infection (WIfI) is endorsed. Objective hemodynamic testing, including toe pressures as the preferred measure, is required to assess CLTI. Evidence-based revascularization (EBR) hinges on three independent axes: Patient risk, Limb severity, and ANatomic complexity (PLAN). Average-risk and high-risk patients are defined by estimated procedural and 2-year all-cause mortality. The GVG proposes a new Global Anatomic Staging System (GLASS), which involves defining a preferred target artery path (TAP) and then estimating limb-based patency (LBP), resulting in three stages of complexity for intervention. The optimal revascularization strategy is also influenced by the availability of autogenous vein for open bypass surgery. Recommendations for EBR are based on best available data, pending level 1 evidence from ongoing trials. Vein bypass may be preferred for average-risk patients with advanced limb threat and high complexity disease, while those with less complex anatomy, intermediate severity limb threat, or high patient risk may be favored for endovascular intervention. All patients with CLTI should be afforded best medical therapy including the use of antithrombotic, lipid-lowering, antihypertensive, and glycemic control agents, as well as counseling on smoking cessation, diet, exercise, and preventive foot care. Following EBR, long-term limb surveillance is advised. The effectiveness of nonrevascularization therapies (eg, spinal stimulation, pneumatic compression, prostanoids, and hyperbaric oxygen) has not been established. Regenerative medicine approaches (eg, cell, gene therapies) for CLTI should be restricted to rigorously conducted randomizsed clinical trials. The GVG promotes standardization of study designs and end points for clinical trials in CLTI. The importance of multidisciplinary teams and centers of excellence for amputation prevention is stressed as a key health system initiative.

Medical and lifestyle management of peripheral arterial disease

OBJECTIVE

Peripheral arterial disease (PAD) is a global health issue associated with impaired functional capacity and elevated risk of major adverse cardiovascular events (MACEs). With changing risk factor profiles and an aging population, the burden of disease is expected to increase. This review considers evidence for the noninvasive management of PAD and makes clinical recommendations accordingly.

METHODS

A comprehensive literature review was performed to examine the evidence for smoking cessation, exercise therapy, antiplatelet therapy, anticoagulant therapy, antihypertensive therapy, lipid-lowering therapy, and glycemic control in diabetes for patients with PAD.

RESULTS

Nicotine replacement, bupropion, and varenicline are safe and more effective than placebo in achieving smoking abstinence. Wherever it is practical and available, supervised exercise therapy is ideal treatment for intermittent claudication. Alternatively, step-monitored exercise can increase walking performance and the participant's compliance with less staff supervision. Clopidogrel is preferable to aspirin alone for all patients. However, small studies support the use of dual antiplatelet therapy after revascularization to improve limb outcomes. More recently, the addition of low-dose rivaroxaban to aspirin alone was proven to be more effective in reducing MACEs without a significant increase in major bleeding. However, the exact role of direct oral anticoagulant therapy in the management of PAD is still being understood. Evidence is emerging for more intensive blood pressure and lipid-lowering therapy than traditional targets. Whereas research in PAD is limited, there is clinical scope for an individualized approach to these risk factors. The management of diabetes remains challenging as glycemic control has not been demonstrated to improve macrovascular outcomes. Any potential impact of glycemic control on microvascular disease needs to be weighed against the risks of hypoglycemia. Sodium-glucose cotransporter 2 inhibitors appear to reduce MACEs, although caution is advised, given the increased incidence of lower limb amputation in clinical trials of canagliflozin.

CONCLUSIONS

Medical and lifestyle management of PAD should aim to improve functional outcomes and to reduce MACEs. Smoking cessation counseling or pharmacotherapy is recommended, although new strategies are needed. Whereas supervised exercise therapy is ideal, there can be barriers to clinical implementation. Other initiatives are being used as an alternative to walking-based supervised exercise therapy. More studies are required to investigate the role of intensive glycemic, blood pressure, and dyslipidemia control in patients with PAD. Overall, a multifactorial approach is recommended to alter the natural history of this condition.

Diabetic Foot Australia guideline on footwear for people with diabetes

Background

The aim of this paper was to create an updated Australian guideline on footwear for people with diabetes.

Methods

We reviewed new footwear publications, (inter)national guidelines, and consensus expert opinion alongside the 2013 Australian footwear guideline to formulate updated recommendations.

Result

We recommend health professionals managing people with diabetes should: (1) Advise people with diabetes to wear footwear that fits, protects and accommodates the shape of their feet. (2) Advise people with diabetes to always wear socks within their footwear, in order to reduce shear and friction. (3) Educate people with diabetes, their relatives and caregivers on the importance of wearing appropriate footwear to prevent foot ulceration. (4) Instruct people with diabetes at intermediate- or high-risk of foot ulceration to obtain footwear from an appropriately trained professional to ensure it fits, protects and accommodates the shape of their feet. (5) Motivate people with diabetes at intermediate- or high-risk of foot ulceration to wear their footwear at all times, both indoors and outdoors. (6) Motivate people with diabetes at intermediate- or high-risk of foot ulceration (or their relatives and caregivers) to check their footwear, each time before wearing, to ensure that there are no foreign objects in, or penetrating, the footwear; and check their feet, each time their footwear is removed, to ensure there are no signs of abnormal pressure, trauma or ulceration. (7) For people with a foot deformity or pre-ulcerative lesion, consider prescribing medical grade footwear, which may include custom-made in-shoe orthoses or insoles. (8) For people with a healed plantar foot ulcer, prescribe medical grade footwear with custom-made in-shoe orthoses or insoles with a demonstrated plantar pressure relieving effect at high-risk areas. (9) Review prescribed footwear every three months to ensure it still fits adequately, protects, and supports the foot. (10) For people with a plantar diabetic foot ulcer, footwear is not specifically recommended for treatment; prescribe appropriate offloading devices to heal these ulcers.

Conclusions

This guideline contains 10 key recommendations to guide health professionals in selecting the most appropriate footwear to meet the specific foot risk needs of an individual with diabetes.

Performance of prognostic markers in the prediction of wound healing or amputation among patients with foot ulcers in diabetes: a systematic review

Prediction of wound healing and major amputation in patients with diabetic foot ulceration is clinically important to stratify risk and target interventions for limb salvage. No consensus exists as to which measure of peripheral artery disease (PAD) can best predict outcomes. To evaluate the prognostic utility of index PAD measures for the prediction of healing and/or major amputation among patients with active diabetic foot ulceration, two reviewers independently screened potential studies for inclusion. Two further reviewers independently extracted study data and performed an assessment of methodological quality using the Quality in Prognostic Studies instrument. Of 9476 citations reviewed, 11 studies reporting on 9 markers of PAD met the inclusion criteria. Annualized healing rates varied from 18% to 61%; corresponding major amputation rates varied from 3% to 19%. Among 10 studies, skin perfusion pressure ≥ 40 mmHg, toe pressure ≥ 30 mmHg (and ≥ 45 mmHg) and transcutaneous pressure of oxygen (TcPO2 ) ≥ 25 mmHg were associated with at least a 25% higher chance of healing. Four studies evaluated PAD measures for predicting major amputation. Ankle pressure < 70 mmHg and fluorescein toe slope < 18 units each increased the likelihood of major amputation by around 25%. The combined test of ankle pressure < 50 mmHg or an ankle brachial index (ABI) < 0.5 increased the likelihood of major amputation by approximately 40%. Among patients with diabetic foot ulceration, the measurement of skin perfusion pressures, toe pressures and TcPO2 appear to be more useful in predicting ulcer healing than ankle pressures or the ABI. Conversely, an ankle pressure of < 50 mmHg or an ABI < 0.5 is associated with a significant increase in the incidence of major amputation.

Effectiveness of revascularization of the ulcerated foot in patients with diabetes and peripheral artery disease: a systematic review

Symptoms or signs of peripheral artery disease (PAD) can be observed in up to 50% of the patients with a diabetic foot ulcer and is a risk factor for poor healing and amputation. In 2012, a multidisciplinary working group of the International Working Group on the Diabetic Foot published a systematic review on the effectiveness of revascularization of the ulcerated foot in patients with diabetes and PAD. This publication is an update of this review and now includes the results of a systematic search for therapies to revascularize the ulcerated foot in patients with diabetes and PAD from 1980 to June 2014. Only clinically relevant outcomes were assessed. The research conformed to the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines, and Scottish Intercollegiate Guidelines Network methodological scores were assigned. A total of 56 articles were eligible for full-text review. There were no randomized controlled trials, but there were four nonrandomized studies with a control group. The major outcomes following endovascular or open bypass surgery were broadly similar among the studies. Following open surgery, the 1-year limb salvage rates were a median of 85% (interquartile range of 80-90%), and following endovascular revascularization, these rates were 78% (70-89%). At 1-year follow-up, 60% or more of ulcers had healed following revascularization with either open bypass surgery or endovascular techniques. Studies appeared to demonstrate improved rates of limb salvage associated with revascularization compared with the results of conservatively treated patients in the literature. There were insufficient data to recommend one method of revascularization over another. There is a real need for standardized reporting of baseline demographic data, severity of disease and outcome reporting in this group of patients.

Effectiveness of bedside investigations to diagnose peripheral artery disease among people with diabetes mellitus: a systematic review

Non-invasive tests for the detection of peripheral artery disease (PAD) among individuals with diabetes mellitus are important to estimate the risk of amputation, ulceration, wound healing and the presence of cardiovascular disease, yet there are no consensus recommendations to support a particular diagnostic modality over another and to evaluate the performance of index non-invasive diagnostic tests against reference standard imaging techniques (magnetic resonance angiography, computed tomography angiography, digital subtraction angiography and colour duplex ultrasound) for the detection of PAD among patients with diabetes. Two reviewers independently screened potential studies for inclusion and extracted study data. Eligible studies evaluated an index test for PAD against a reference test. An assessment of methodological quality was performed using the quality assessment for diagnostic accuracy studies instrument. Of the 6629 studies identified, ten met the criteria for inclusion. In these studies, the patients had a median age of 60-74 years and a median duration of diabetes of 9-24 years. Two studies reported exclusively on patients with symptomatic (ulcerated/infected) feet, two on patients with asymptomatic (intact) feet only, and the remaining six on patients both with and without foot ulceration. Ankle brachial index (ABI) was the most widely assessed index test. Overall, the positive likelihood ratio and negative likelihood ratio (NLR) of an ABI threshold <0.9 ranged from 2 to 25 (median 8) and <0.1 to 0.7 (median 0.3), respectively. In patients with neuropathy, the NLR of the ABI was generally higher (two out of three studies), indicating poorer performance, and ranged between 0.3 and 0.5. A toe brachial index <0.75 was associated with a median positive likelihood ratio and NLRs of 3 and ≤ 0.1, respectively, and was less affected by neuropathy in one study. Also, in two separate studies, pulse oximetry used to measure the oxygen saturation of peripheral blood and Doppler wave form analyses had NLRs of 0.2 and <0.1. The reported performance of ABI for the diagnosis of PAD in patients with diabetes mellitus is variable and is adversely affected by the presence of neuropathy. Limited evidence suggests that toe brachial index, pulse oximetry and wave form analysis may be superior to ABI for diagnosing PAD in patients with neuropathy with and without foot ulcers. There were insufficient data to support the adoption of one particular diagnostic modality over another and no comparisons existed with clinical examination. The quality of studies evaluating diagnostic techniques for the detection of PAD in individuals with diabetes is poor. Improved compliance with guidelines for methodological quality is needed in future studies.