A Framework for the Evaluation of “Value” and Cost-Effectiveness in the Management of Critical Limb Ischemia

Cost-effectiveness analysis of intravascular ultrasound-guided peripheral vascular interventions in patients with femoropopliteal peripheral artery disease

Background: Intravascular ultrasound (IVUS)-guided percutaneous transluminal angioplasty (PTA) might offer clinical benefits compared to angiography-guided PTA in patients with peripheral artery disease (PAD). A cost-effectiveness model was developed to examine the benefits and costs of IVUS-guided PTA versus angiography-guided PTA in PAD patients with femoropopliteal (FP) occlusive disease. Methods: A two-step model (a one-year decision tree followed by a lifetime semi-Markov model) was developed from a German healthcare payer perspective to estimate the costs and outcomes over a one-year and lifetime horizon. Clinical events included target lesion revascularization (TLR), amputation, and death. Transition probabilities and utility values were derived from published literature. Healthcare costs were based on German Diagnosis Related Groups (DRG) codes. Costs and outcomes were discounted at a rate of 3% per year. The incremental cost-effectiveness ratio (ICER) was calculated, and sensitivity analyses were performed to assess the robustness of the results. Results: In the one-year horizon, IVUS-guided PTA resulted in incremental quality-adjusted life-years (QALY) and costs of 0.02 and €919 per patient respectively, with a corresponding ICER of €45,195/QALY gained versus angiography-guided PTA. In the lifetime horizon, IVUS-guided PTA outperforms angiography-guided PTA; it was associated with a cost saving of €46 per patient and incremental QALY of 0.22. Utility value for post-TLR, as well as probabilities of death and TLR had the greatest impact on the one-year ICER, while cost of TLR and probabilities of TLR and amputation influenced the lifetime ICER most. The probability of IVUS-guided PTA being cost-effective at a willingness-to-pay (WTP) threshold of €50,000/QALY was 50.4% in the one-year horizon and increased to 85.9% in the lifetime horizon. Conclusions: In this analysis IVUS-guided PTA among patients with symptomatic FP atherosclerosis was cost-saving in a lifetime horizon from the German healthcare payer perspective.

Specialist access and leg amputations among Texas Medicaid patients

Medicaid coverage among patients with peripheral artery disease (PAD) has been associated with higher rates of primary amputations. We sought to determine the relative contributions of clinical, demographic, and hospital factors to leg amputations among Texas Medicaid patients. Patient-level data were used to identify patients who underwent treatment for PAD-related foot complications in Texas. Patients were categorized into groups by insurance provider (Medicaid, Medicare, dual-enrollee, commercial, and provider network). Individual- and area-level multivariate analyses were used to find associations with primary amputation. Of 21,592 patients identified, 8.8% were covered by Medicaid, 35.3% by Medicare, 27.8% by Medicare and Medicaid, 7.3% by commercial insurance, and 20.7% by a provider network. Compared with commercially insured patients, Medicaid patients more often underwent amputation (33% v 49%), were categorized as Black or Hispanic (45% v 64%), presented with gangrene (61% v 71%), were admitted through an emergency department (61% v 73%), and were admitted to a safety net hospital (3% v 16%). They had lower relative rates of outpatient evaluation (1.33 v 0.55) and their hospitalizations were less centralized (Gini coefficient 0.43 v 0.39) (P < .001 for all). Amputations among Medicaid patients were associated with infection and gangrene, care at safety net hospitals, rate of outpatient visits, and Black and Hispanic race, even after risk-adjustment (P < .001). Leg amputations among Medicaid patients were associated with race, disease severity, hospital characteristics, and outpatient evaluation rates, but not with provider density and location. Focusing efforts on preventative care and early outpatient referrals could help address this disparity.

Lower-extremity pressure, staging, and grading thresholds to identify chronic limb-threatening ischemia

INTRODUCTION

The Society for Vascular Surgery Threatened Limb Classification System ('WIfI') is used to predict risk of limb loss and identify peripheral artery disease in patients with foot ulcers or gangrene. We estimated the diagnostic sensitivity of multiple clinical and noninvasive arterial parameters to identify chronic limb-threatening ischemia (CLTI).

METHODS

We performed a single-center review of 100 consecutive patients who underwent angiography for foot gangrene or ulcers. WIfI stages and grades were determined for each patient. Toe, ankle, and brachial pressure measurements were performed by registered vascular technologists. CLTI severity was characterized using Global Limb Anatomic Staging System (GLASS stages) and angiosomes. Medial artery calcification in the foot was quantified on foot radiographs.

RESULTS

GLASS NA (not applicable), I, II, and III angiographic findings were seen in 21, 21, 23, and 35 patients, respectively. A toe-brachial index < 0.7 and minimum ipsilateral ankle-brachial index < 0.9 performed well in identifying GLASS II and III angiographic findings, with sensitivity rates 97.8% and 91.5%, respectively. The diagnostic accuracy rates of noninvasive measures peaked at 74.7% and 89.3% for identifying GLASS II/III and GLASS I+ angiographic findings, respectively. The presence of medial artery calcification significantly diminished the sensitivity of most noninvasive parameters.

CONCLUSIONS

The use of alternative noninvasive arterial testing parameters improves sensitivity for detecting PAD. Abnormal noninvasive results should suggest the need for diagnostic angiography to further characterize arterial anatomy of the affected limb. Testing strategies with better accuracy are needed.

Cost-utility analysis of early versus delayed endovascular intervention in critical limb-threatening ischemia patients with rest pain

OBJECTIVE

The prevalence of chronic limb-threatening ischemia (CLTI) and poor health outcomes are high in Germany. Serious consequences of CLTI such as amputation and mortality can be effectively prevented by the early use of evidence-based therapeutic measures such as endovascular intervention. We have developed a cost-utility analysis to compare endovascular intervention with bare metal stents (BMSs) and endovascular intervention after conservative treatment from the German payer perspective.

METHODS

A Markov model, with a 5-year time horizon and seven states, was developed: (1) intervention, (2) stable 1, (3) major amputation, (4) reintervention, (5) stable 2, (6) care, and (7) all-cause death. Transition probabilities were obtained by pooling the outcomes from multiple clinical studies. The costs were estimated using data from the German diagnosis-related group system, the German rehabilitation fund, and related literature. Health-state utilities were obtained from the reported data. The primary outcomes were the quality-adjusted life-years (QALYs) and costs.

RESULTS

Early BMS intervention after 5 years resulted in a cost of €23,913 and an increase of 2.5 QALYs per patient, and endovascular intervention with BMS after conservative treatment after 5 years resulted in a cost of €18,323 and an increase of 2 QALYs per patient. The incremental cost-effectiveness ratio was €12,438. The number of major amputations was reduced by 6%. The results of the structural, deterministic, and probabilistic sensitivity analyses were robust.

CONCLUSIONS

Early endovascular intervention with BMS resulted in more QALYs and a reduced risk of major amputation for early-stage CLTI patients. Our results showed that early endovascular intervention is very cost-effective according to World Health Organization recommended cost-effectiveness thresholds. However, the clinical decision regarding the use of early endovascular intervention should be determined by individual patient-level eligibility and the physician's judgment.

Cost-Effectiveness Analysis for the Treatment of Diabetic Foot Ulcer in France: Platelet-Rich Plasma vs Standard of Care

Introduction

Diabetic chronic foot ulcers (DFU) lead to pain, reduced quality of life and represent a severe economic burden for patients and health systems. The clinical results of PRP effectiveness in the treatment of DFU are promising; on the other hand, the costs associated with treating DFUs with PRP are higher than those using standard therapy. Therefore, this study aims to determine the cost-effectiveness of platelet-rich plasma (PRP) therapy compared to standard therapy from the French healthcare system perspective.

Methods

A cost-effectiveness analysis (CEA) was performed using a decision Markov model with a cohort of patients with chronic DFU (duration of >3 weeks) with high orthopaedic risk and with ulcers graded 3A according to University of Texas classification. The effectiveness outcomes are reported in terms of quality adjusted life year (QALY). The costs are reported in euro (€) currency evaluated in 2019. A micro-costing approach alongside a clinical study was used to assess resource use. Deterministic sensibility analyses are reported to evaluate the robustness of the results. The analyses were carried out in the French setting.

Results

The incremental cost-effectiveness ratio (ICER) of PRP treatment is –€613/ QALY, which, being lower than zero, indicates the dominance of the PRP therapy. Deterministic and probabilistic sensitivity analysis underlines the main parameter affecting CE results. Lowest number of standard of care weekly medications (from 5 to 3) leads to a €622/QALY while increasing PRP weekly medication (from 1 to 4) has an ICER of €732/QALY.

Discussion

PRP is a cost-effective or even a cost-saving alternative in the French setting. PRP has higher cost for the complete medication, but, in the absence of wound complications, has the potential to involve lower consumption of resources in the form of routine medication over a 1-year time horizon.

The Burden of Patients With Lower Limb Amputations in a Community Safety-net Hospital

BACKGROUND

The functional disability after amputation is tremendous and imposes a high economic burden on patients and health systems. The current literature on the costs of amputation has been limited to the index hospitalization or a short time window around the amputation procedure, which covers a small percentage of the total costs.

METHODS

We conducted a retrospective cohort study of patients who underwent lower extremity amputations at a single urban public level 1 trauma hospital. Resource utilization and healthcare costs 1 year before and 1 year after the index amputation were examined. Hospitalization costs were estimated using cost center-based cost-to-charge ratios for the 2-year follow-up.

RESULTS

The sample comprised 90 patients (73 men and 17 women) with a mean age of 55.9 years (SD, 9.9). Most amputations were secondary to diabetes (74%) and vascular disease in the absence of diabetes (22%). During the 2-year window around the index amputation, patients had an average of 2.7 admissions (SD, 2.3), mean index length of stay of 14.6 days (SD, 22.3), and a mean cumulative length of stay of 31.3 days (SD, 43.4). The patients had a mean of 2.3 (SD, 3.2) additional procedures performed on their amputated limb. Twenty-one patients (23%) required additional proximal amputations, with an average change of 2.2 (SD, 1.6) levels. The mean cost, per patient, of the index hospitalization was $51,481. Over the 2-year period, the mean cost of hospitalizations was $114,292 per patient with a total cost, summed over the cohort, of $10,286,250. Approximately 64% of the total cost went uncompensated.

DISCUSSION

Over a 2-year window, amputees endured multiple procedures, readmissions, and reamputations, leading to high healthcare costs. Further research into resource-conscious interventions and programs is needed to control the burdens faced by amputees and the health systems that care for them.

Treatment of Peripheral Arterial Occlusive Disease around the Globe: Malta

INTRODUCTION

Malta is a small island in the middle of the Mediterranean with a population of 514,564 inhabitants and is served by one public tertiary hospital, Mater Dei Hospital. The Vascular unit was set up in 2007. The aim of this review is to analyse the work related to peripheral arterial occlusive disease (PAOD) in Malta with an in-depth focus on amputations and revascularisation procedures since the introduction of the Vascular unit.

METHOD

Various sources of data have been interrogated to address this subject. Population and prevalence data on obesity and type II diabetes mellitus from 2003 to 2019 was obtained from the National Statistics Office, the World Health Organization, and the International Diabetes Federation, respectively. The Maltese Vascular Register (MaltaVasc), and in-hospital reports from 2003 to 2019 was used to obtain data on revascularisation procedures, major amputations and minor amputation rates in Malta.

RESULTS

Malta has one of the highest rates of obesity in Europe. In 2015, the prevalence rate was 30.6%. Similarly, data from the International Diabetes Federation Atlas showed that the prevalence rate of T2DM among adults was 14% in 2017. There was a mean of 33 open/hybrid procedures per 100,000 population (28-38, 95% confidence interval) between 2005 and 2009 and a mean of 57 endovascular procedures per 100,000 population (46-68, 95% confidence interval) during the same time-period. From 2009 to 2019, there was a mean of 16 major amputations and 78 minor amputations per 100,000 population.

CONCLUSION

A significant reduction in major amputation rates with an increase in minor amputation rates and revascularisation rates has been noted since the establishment of the vascular unit in Malta. During this period, there has been an increase in prevalence in obesity and T2DM together with an aging population.

Angiogenic effects of cell therapy within a biomaterial scaffold in a rat hind limb ischemia model

Critical limb ischemia (CLI) is a life- and limb-threatening condition affecting 1-10% of humans worldwide with peripheral arterial disease. Cellular therapies, such as bone marrow-derived mesenchymal stem cells (MSCs) have been used for the treatment of CLI. However, little information is available regarding the angiogenic potency of MSCs and mast cells (MC) in angiogenesis. The aim of this study was to evaluate the ability of MCs and MSCs to induce angiogenesis in a rat model of ischemic hind limb injury on a background of a tissue engineered hydrogel scaffold. Thirty rats were randomly divided into six control and experimental groups as follows: (a) Control healthy (b) Ischemic positive control with right femoral artery transection, (c) ischemia with hydrogel scaffold, (d) ischemia with hydrogel plus MSC, (e) ischemia with hydrogel plus MC and (f) ischemia with hydrogel plus MSC and MCs. 106 of each cell type, isolated from bone marrow stroma, was injected into the transected artery used to induce hind limb ischemia. The other hind limb served as a non-ischemic control. After 14 days, capillary density, vascular diameter, histomorphometry and immunohistochemistry at the transected location and in gastrocnemius muscles were evaluated. Capillary density and number of blood vessels in the region of the femoral artery transection in animals receiving MSCs and MCs was increased compared to control groups (P < 0.05). Generally the effect of MCs and MSCs was similar although the combined MC/MSC therapy resulted in a reduced, rather than enhanced, effect. In the gastrocnemius muscle, immunohistochemical and histomorphometric observation showed a great ratio of capillaries to muscle fibers in all the cell-receiving groups (P < 0.05). The data indicates that the combination of hydrogel and cell therapy generates a greater angiogenic potential at the ischemic site than cell therapy or hydrogels alone.

A single center's 15-year experience with palliative limb care for chronic limb threatening ischemia in frail patients

OBJECTIVE

Our institution's multidisciplinary Prevention of Amputation in Veterans Everywhere (PAVE) program allocates veterans with critical limb threatening ischemia (CLTI) to immediate revascularization, conservative, primary amputation or palliative limb care based on previously published criteria. These four groups align with the approaches outlined by the Global Guidelines for management of CLTI. The current study delineates the natural history of the palliative limb care group of patients and quantifies procedural risks and outcomes.

METHODS

Veterans prospectively enrolled into the palliative limb cohort of our PAVE program between January 2005 and January 2020 were analyzed. The primary outcome was mortality. Secondary outcomes included overall and limb-related readmissions, limb loss and wound healing. Clinical Frailty Score (CFS) was calculated and 5-year expected mortalities were estimated using the Veterans Administration Quality Enhancement Research Initiative (VA QUERI) tool. Regression analysis was performed to establish associations among the following variables: mortality, WIfI score, Clinical Frailty Score, overall admissions and limb-related admissions.

RESULTS

The PAVE program enrolled 1158 limbs over 15 years. 157 (13.5%) limbs in 145 patients were allocated to the palliative limb care group. The overall mortality of the group was 88.2% (median 3.5 months; range 0-91 months). Of the patients that expired, 50% (n=64) died within 3 months of enrollment. The predicted 5-year mortality for the group was 66%. The average frailty score of the group was 6.2, denoting someone who is moderately to severely frail. Based on CFS, 106 patients were considered frail while 39 were considered not frail. There was no difference in mortality between frail and non- frail patients, however there was a statistically significant difference in early mortality (<3 months), 56.2% vs 37.5% (p = 0.032), respectively. The 30-day limb-related readmission rate was 4.7%. Eventual major amputation was necessary in 18 (11.5%) limbs. Wound healing occurred in 30 patients (20.6%). Regression analysis demonstrated no association between frailty score and mortality (r = 0.55, p = 0.159) or between WIfI score and mortality (r = 0.0165, p = 0.98). There was a significant association between WIfI score and limb-related admissions (r = 0.97, p <0.001).

CONCLUSION

Frail, chronic limb threatening ischemia patients have a high early mortality and a low risk of limb-related complications. They also have a low incidence of deferred primary amputation or limb-related readmissions. In our cohort, the vast majority of patients died within a few months of enrollment without needing an amputation. A comprehensive approach to the management of CLTI patients should include a palliative limb care option as a significant proportion of these patients have limited survival and can potentially avoid unnecessary surgery or major amputation.

Procedural and 12-month in-hospital costs of primary infra-popliteal bypass surgery, infra-popliteal best endovascular treatment, and major lower limb amputation for chronic limb threatening ischemia

OBJECTIVE

Chronic limb-threatening ischemia (CLTI) is a growing global problem due to the widespread use of tobacco and increasing prevalence of diabetes. Although the financial consequences are considerable, few studies have compared the relative cost-effectiveness of different CLTI management strategies. The Bypass vs Angioplasty in Severe Ischaemia of the Leg (BASIL)-2 trial is randomizing patients with CLTI to primary infra-popliteal (IP) vein bypass surgery (BS) or best endovascular treatment (BET) and includes a comprehensive within-trial cost-utility analysis. The aim of this study is to compare over a 12-month time horizon, the costs of primary IP BS, IP best endovascular treatment (BET), and major limb major amputation (MLLA) to inform the BASIL-2 cost-utility analysis.

METHODS

We compared procedural human resource (HR) costs and total in-hospital costs for the index admission, and over the following 12-months, in 60 consecutive patients undergoing primary IP BS (n = 20), IP BET (n = 20), or MLLA (10 transfemoral and 10 transtibial) for CLTI within the BASIL prospective cohort study.

RESULTS

Procedural HR costs were greatest for BS (BS £2551; 95% confidence interval [CI], £1934-£2807 vs MLLA £1130; 95% CI, £1046-£1297 vs BET £329; 95% CI, £242-£390; P < .001, Kruskal-Wallis) due to longer procedure duration and greater staff requirement. With regard to the index admission, MLLA was the most expensive due to longer hospital stay (MLLA £13,320; 95% CI, £8986-£18,616 vs BS £8714; 95% CI, £6097-£11,973 vs BET £4813; 95% CI, £3529-£6097; P < .001, Kruskal-Wallis). The total cost of the index admission and in-hospital care over the following 12 months remained least for BET (MLLA £26,327; 95% CI, £17,653-£30,458 vs BS £20,401; 95% CI, £12,071-£23,926 vs BET £12,298; 95% CI, £6961-£15,439; P < .001, Kruskal-Wallis).

CONCLUSIONS

Over a 12-month time horizon, MLLA and IP BS are more expensive than IP BET in terms of procedural HR costs and total in-hospital costs. These economic data, together with quality of life data from BASIL-2, will inform the calculation of incremental cost-effectiveness ratios for different CLTI management strategies within the BASIL-2 cost-utility analysis.

Risk assessments and structured care interventions for prevention of foot ulceration in diabetes: development and validation of a prognostic model

BACKGROUND

Diabetes-related foot ulcers give rise to considerable morbidity, generate a high monetary cost for health and social care services and precede the majority of diabetes-related lower extremity amputations. There are many clinical prediction rules in existence to assess risk of foot ulceration but few have been subject to validation.

OBJECTIVES

Our objectives were to produce an evidence-based clinical pathway for risk assessment and management of the foot in people with diabetes mellitus to estimate cost-effective monitoring intervals and to perform cost-effectiveness analyses and a value-of-information analysis.

DESIGN

We developed and validated a prognostic model using predictive modelling, calibration and discrimination techniques. An overview of systematic reviews already completed was followed by a review of randomised controlled trials of interventions to prevent foot ulceration in diabetes mellitus. A review of the health economic literature was followed by the construction of an economic model, an analysis of the transitional probability of moving from one foot risk state to another, an assessment of cost-effectiveness and a value-of-information analysis.

INTERVENTIONS

The effects of simple and complex interventions and different monitoring intervals for the clinical prediction rules were evaluated.

MAIN OUTCOME MEASURE

The main outcome was the incidence of foot ulceration. We compared the new clinical prediction rules in conjunction with the most effective preventative interventions at different monitoring intervals with a 'treat-all' strategy.

DATA SOURCES

Data from an electronic health record for 26,154 people with diabetes mellitus in one Scottish health board were used to estimate the monitoring interval. The Prediction Of Diabetic foot UlcerationS (PODUS) data set was used to develop and validate the clinical prediction rule.

REVIEW METHODS

We searched for eligible randomised controlled trials of interventions using search strategies created for Ovid® (Wolters Kluwer, Alphen aan den Rijn, the Netherlands), MEDLINE, EMBASE and the Cochrane Central Register of Controlled Trials. Randomised controlled trials in progress were identified via the International Standard Randomised Controlled Trial Number Registry and systematic reviews were identified via PROSPERO. Databases were searched from inception to February 2019.

RESULTS

The clinical prediction rule was found to accurately assess the risk of foot ulceration. Digital infrared thermometry, complex interventions and therapeutic footwear with offloading devices were found to be effective in preventing foot ulcers. The risk of developing a foot ulcer did not change over time for most people. We found that interventions to prevent foot ulceration may be cost-effective but there is uncertainty about this. Digital infrared thermometry and therapeutic footwear with offloading devices may be cost-effective when used to treat all people with diabetes mellitus regardless of their ulcer risk.

LIMITATIONS

The threats to the validity of the results in some randomised controlled trials in the review and the large number of missing data in the electronic health record mean that there is uncertainty in our estimates.

CONCLUSIONS

There is evidence that interventions to prevent foot ulceration are effective but it is not clear who would benefit most from receiving the interventions. The ulceration risk does not change over an 8-year period for most people with diabetes mellitus. A change in the monitoring interval from annually to every 2 years for those at low risk would be acceptable.

FUTURE WORK RECOMMENDATIONS

Improving the completeness of electronic health records and sharing data would help improve our knowledge about the most clinically effective and cost-effective approaches to prevent foot ulceration in diabetes mellitus.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42016052324.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 24, No. 62. See the NIHR Journals Library website for further project information.

2D perfusion DSA with an open-source, semi-automated, color-coded software for the quantification of foot perfusion following infrapopliteal angioplasty: a feasibility study

BACKGROUND

Foot perfusion has been recently implemented as a new tool for optimizing outcomes of peripheral endovascular procedures. A custom-made, two-dimensional perfusion digital subtraction angiography (PDSA) algorithm has been implemented to quantify outcomes of endovascular treatment of critical limb ischemia (CLI), assist intra-procedural decision-making, and enhance clinical outcomes.

METHODS

The study was approved by the Hospital's Ethics Committee. This prospective, single-center study included seven consecutive patients scheduled to undergo infrapopliteal endovascular treatment of CLI. Perfusion blood volume (PBV), mean transit time (MTT), and perfusion blood flow (PBF) maps were extracted by analyzing time-intensity curves and signal intensity on the perfused vessel mask. Mean values calculated from user-specified regions of interest (ROIs) on perfusion maps were employed to evaluate pre- and post-endovascular treatment condition. Measurements were performed immediately after final PDSA.

RESULTS

In total, five patients (aged 54 ± 16 years, mean ± standard deviation) were analyzed, as two patients were excluded due to significant motion artifacts. Post-procedural MTT presented a mean decrease of 19.1% for all patients and increased only in 1 of 5 patients, demonstrating in 4/5 patients an increase in tissue perfusion after revascularization. Overall mean PBF and PBV values were also analogously increased following revascularization (446% and 69.5% mean, respectively) and in the majority of selected ROIs (13/15 and 12/15 ROIs, respectively).

CONCLUSIONS

Quantification of infrapopliteal angioplasty outcomes using this newly proposed, custom-made, intra-procedural PDSA algorithm was performed using PBV, MTT, and PBF maps. Further studies are required to determine its role in peripheral endovascular procedures ( ClinicalTrials.gov Identifier: NCT04356092).

Quality of Life and Traditional Outcome Results at 1 Year in Elderly Patients Having Critical Limb Ischemia and the Role of Conservative Treatment

Introduction:

Revascularization is the cornerstone of the treatment of critical limb ischemia (CLI), but the number of elderly frail patients increase. Revascularization is not always possible in these patients and conservative therapy seems to be an option. The goals of this study are to analyze the 1-year quality of life (QoL) results and mortality rates of elderly patients with CLI and to investigate if conservative treatment could be an acceptable treatment option.

Methods:

Patients with CLI ≥70 years old were included in a prospective observational cohort study in 2 hospitals in the Netherlands between 2012 and 2016 and were divided over 3 treatment modalities: endovascular therapy, surgical revascularization, and conservative treatment. The World Health Organization Quality of Life (WHOQoL-Bref) instrument, a generic QoL assessment tool that includes components of physical, psychological, social relationships and environment, was used to evaluate QoL at baseline, 6 months, and 1 year.

Results:

In total, 195 patients (56% male, 33% Rutherford 4, mean age of 80) were included. Physical QoL significantly increased after surgical (10.4 vs 14.9, P < .001), endovascular (10.9 vs 13.7, P < .001), and conservative therapy (11.6 vs 13.2, P = .01) at 1 year. One-year mortality was relatively low after surgery (10%) compared to endovascular (40%) and conservative therapy (37%).

Conclusion:

The results of this study could not be used to designate the superior treatment used in elderly patients with CLI. Conservative treatment could be an acceptable treatment option in selected patients with CLI unfit for revascularization. Treatment of choice in elderly patients with CLI is based on multiple factors and should be individualized in a shared decision-making process.

The burden of critical limb ischemia: a review of recent literature

Peripheral arterial disease is a chronic vascular disease characterized by impaired circulation to the lower extremities. Its most severe stage, known as critical limb ischemia (CLI), puts patients at an increased risk of cardiovascular events, amputation, and death. The objective of this literature review is to describe the burden of disease across a comprehensive set of domains—epidemiologic, clinical, humanistic, and economic—focusing on key studies published in the last decade. CLI prevalence in the United States is estimated to be approximately 2 million and is likely to rise in the coming years given trends in important risk factors such as age, diabetes, and smoking. Hospitalization for CLI patients is common and up to 60% are readmitted within 6 months. Amputation rates are unacceptably high with a disproportionate risk for certain demographic and socioeconomic groups. In addition to limb loss, CLI patients also have reduced life expectancy with mortality typically exceeding 50% by 5 years. Given the poor clinical prognosis, it is unsurprising that the quality of life burden associated with CLI is significant. Studies assessing quality of life in CLI patients have used a variety of generic and disease-specific measures and all document a substantial impact of the disease on the patient’s physical, social, and emotional health status compared to population norms. Finally, the poor clinical outcomes and increased medical resource use lead to a considerable economic burden for national health care systems. However, published cost studies are not comprehensive and, therefore, likely underestimate the true economic impact of CLI. Our summary documents a sobering assessment of CLI burden—a poor clinical prognosis translating into diminished quality of life and high costs for millions of patients. Continued prevention efforts and improved treatment strategies are the key to ameliorating the substantial morbidity and mortality associated with this disease.

Advances in the Management of Peripheral Artery Disease

PURPOSE OF REVIEW

This paper provides a concise update on the management of peripheral artery disease (PAD).

RECENT FINDINGS

PAD continues to denote a population at high risk for mortality but represents a threat for limb loss only when associated with foot ulcers, gangrene, or infections. Performing either angiogram or non-invasive testing for all patients with foot ulcers, gangrene, or foot infections will help increase the detection of PAD, and refined revascularization strategies may help optimize wound healing in this patient group. Structured exercise programs are becoming available to more patients with claudication as methods to improve adherence to community-based exercise programs will improve. Finally, ensuring more patients with PAD receive aspirin therapy and statins may improve long-term survival, while further research will help determine if adding newer antiplatelet or anticoagulant medications may reduce leg amputations in selected patients. Clinicians should have a low threshold to obtain an angiogram and to pursue revascularization in patients with foot ulcers, gangrene, or foot infections. In patients with claudication, clinicians should maximize the benefits derived from exercise therapy and medical management before offering percutaneous or surgical revascularization.

The burden of amputation in patients with peripheral arterial disease in the Netherlands

INTRODUCTION

Peripheral arterial disease (PAD) can lead to severe cases of critical limb ischemia (CLI), which in turn might lead to amputation. Amputation can have substantial consequences for patients. This publication aims to give a better understanding of the amputation-related burden in patients with PAD in the Netherlands.

EVIDENCE ACQUISITION

A systematic review and grey literature searches were conducted followed by qualitative interviews with a multidisciplinary team of clinical experts in amputation. Subsequently, IQVIA's Dutch hospital claims data were analyzed.

EVIDENCE SYNTHESIS

Twenty-seven publications were identified. Dutch claims data identified claims for 2328 patients after amputation for PAD. Data for the following topics were found: incidence, mortality, complications, mobility, daily functioning, quality of life, utilities, length of stay (LoS), costs, and resource use. Annually, 90% of the 3300 amputations carried out in the Netherlands were due to vascular disease. One-year mortality in patients with an amputation ranged from 49.6% (above-the-knee amputation) to 9% (specialized care). Patients' quality of life was substantially affected and utility of post-major amputation for PAD was 0.54. LoS after amputation varied from 11.4 (general rehabilitation) to 53.4 days (amputation of the leg). Total budget incurred based on frequently claimed DBC's from Dutch claims data in patients with PAD undergoing an amputation over 2012 to 2016 was € 136,651,374. Mean cost per patient was € 17,821.

CONCLUSIONS

Amputation leads to substantial burden in patients with PAD in the Netherlands. Identified results give a better understanding of the specific Dutch burden of amputation.

Long-Term Wound Palliation to Manage Exposed Hardware in the Setting of Peripheral Arterial Disease

Exposed orthopedic hardware in the lower extremity complicated by peripheral arterial disease typically demands multiple operative procedures by several disciplines to maintain skeletal integrity and achieve complete wound healing. For ambulatory patients that are either not candidates for lower extremity revascularization or prefer not to pursue surgical attempts at limb preservation, wound palliation is a potential management strategy. We discuss a patient with a history of severe peripheral arterial disease and a left pilon fracture previously treated with open reduction and internal fixation. He presented with a 2-month history of open wounds and exposed hardware over his left tibia. Though he initially underwent surgical revascularization to improve circulation to his lower extremity, the arterial bypass occluded within 6 months of the operation. At that point, the patient decided to forego any additional surgical intervention, including hardware removal, in favor of local wound care and expectant management. Remarkably, the wound remained stable in size over the next 14 years, he remained ambulatory, and never developed a deep wound infection. Though palliative wound care alone is understandably not the recommended first-line therapy for managing nonhealing wounds, it may be a safe and potentially durable alternative to major lower extremity amputation when revascularization and soft-tissue coverage cannot be achieved.

Efficient Differentiation of Bone Marrow Mesenchymal Stem Cells into Endothelial Cells in Vitro

OBJECTIVE

Endothelial cells (ECs) play an important role in neovascularisation, but are too limited in number for adequate therapeutic applications. Mesenchymal stem cells (MSCs) have the potential to differentiate into endothelial lineage cells, which makes them attractive candidates for therapeutic angiogenesis. The aim of this study was to investigate efficient differentiation of MSCs into ECs by inducing medium in vitro.

METHODS

MSCs were isolated from bone marrow by density gradient centrifugation. The characterisation of the MSCs was determined by their cluster of differentiation (CD) marker profile. Inducing medium containing vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), insulin like growth factor (IGF), epidermal growth factor (EGF), ascorbic acid, and heparin was applied to differentiate the MSCs into ECs. Endothelial differentiation was quantitatively evaluated using flow cytometry. Real time quantitative PCR (qRT-PCR) was used to analyse mRNA expression of endothelial markers. Tube formation assay was further performed to examine the functional status of the differentiated MSCs.

RESULTS

Flow cytometry analysis demonstrated that CD31⁺ and CD34⁺ cells increased steadily from 12% at 3 days, to 40% at 7 days, and to 60% at 14 days. Immunofluorescence staining further confirmed the expression of CD31 and CD34. qRT-PCR showed that expression of von Willebrand factor (vWF), vascular endothelial cadherin (VE-cadherin) and vascular endothelial growth factor receptor-2 (VEGFR-2) were significantly higher in the induced MSCs group compared with the uninduced MSCs group. The functional behavior of the differentiated cells was tested by tube formation assay in vitro on matrigel. Induced MSCs were capable of developing capillary networks, and progressive formation of vessel like structures was associated with increased EC population.

CONCLUSIONS

These results provide a method to efficiently promote differentiation of MSCs into ECs in vitro for potential application in the treatment of peripheral arterial disease.

Regional variation in the cost of infrainguinal lower extremity bypass surgery in the United States

BACKGROUND

Lower extremity bypass (LEB) remains the gold standard revascularization procedure in patients with peripheral arterial disease. The cost of LEB substantially varies based on patient's characteristics and comorbidities. The aim of this study was to assess regional variation in infrainguinal LEB cost and to identify the specific health care expenditures per service that are associated with the highest cost in each region.

METHODS

We identified adult patients who underwent infrainguinal LEB in the Premier database between June 2009 and March 2015. Generalized linear regression models were used to report differences between regions in total in-hospital cost and service-specific cost adjusting for patient's demographics, clinical characteristics, and hospital factors.

RESULTS

A total of 50,131 patients were identified. The median in-hospital cost was $13,259 (interquartile range, $9308-$19,590). The cost of LEB was significantly higher in West and Northeast regions with a median cost of nearly $16,000. The high cost in the Northeast region was driven by the fixed (indirect) cost, whereas the driver of the high cost in the West region was the variable (direct) cost. The adjusted total in-hospital cost was significantly higher in all regions compared with the South (mean difference, West, $3752 [95% confidence interval (CI), 3477-4027]; Northeast, $2959 [95% CI, 2703-3216]; Midwest, 1586 [95% CI, 1364-1808]).

CONCLUSIONS

In this study, we show the marked regional variability in LEB costs. This disparity was independent from patient clinical condition and hospital factors. Cost inequality across the US represents a financial burden on both the patient and the health system.

A nationwide analysis of 30-day readmissions related to critical limb ischemia

Objectives There is paucity of information regarding critical limb ischemia-related readmission rates in patients admitted with critical limb ischemia. We studied 30-day critical limb ischemia-related readmission rate, its predictors, and clinical outcomes using a nationwide real-world dataset. Methods We did a secondary analysis of the 2013 Nationwide Readmissions Database. We included all patients with a primary diagnosis of extremity rest pain, ulceration, and gangrene secondary to peripheral arterial disease. From this group, all patients readmitted with similar diagnosis within 30 days were recorded. Results Of the total 25,111 index hospitalization for critical limb ischemia, 1270 (5%) were readmitted with a primary diagnosis of critical limb ischemia within 30 days. The readmission rate was highest (9.5%) for the group that did not have any intervention (revascularization or major amputation) and was lowest for surgical revascularization and major amputation groups (2.6% and 1.3%, P value <0.001 for all groups). Severity of critical limb ischemia at index admission was associated with a significantly higher rate of 30-day readmission. Critical limb ischemia-related readmission was associated with a higher rate of major amputation (29.6% vs. 16.2%, P<0.001), a lower rate of any revascularization procedure (46% vs. 62.6%, P<0.001), and a higher likelihood of discharge to a skilled nursing facility (43.2% vs. 32.2%, P<0.001) compared to index hospitalization. Conclusions In patients with primary diagnosis of critical limb ischemia, 30-day critical limb ischemia-related readmission rate was affected by initial management strategy and the severity of critical limb ischemia. Readmission was associated with a significantly higher rate of amputation, increased length of stay, and a more frequent discharge to an alternate care facility than index admission and thus may serve as a useful quality of care metric in critical limb ischemia patients.

A model to estimate cost-savings in diabetic foot ulcer prevention efforts

BACKGROUND

Sustained efforts at preventing diabetic foot ulcers (DFUs) and subsequent leg amputations are sporadic in most health care systems despite the high costs associated with such complications. We sought to estimate effectiveness targets at which cost-savings (i.e. improved health outcomes at decreased total costs) might occur.

METHODS

A Markov model with probabilistic sensitivity analyses was used to simulate the five-year survival, incidence of foot complications, and total health care costs in a hypothetical population of 100,000 people with diabetes. Clinical event and cost estimates were obtained from previously-published trials and studies. A population without previous DFU but with 17% neuropathy and 11% peripheral artery disease (PAD) prevalence was assumed. Primary prevention (PP) was defined as reducing initial DFU incidence.

RESULTS

PP was more than 90% likely to provide cost-savings when annual prevention costs are less than $50/person and/or annual DFU incidence is reduced by at least 25%. Efforts directed at patients with diabetes who were at moderate or high risk for DFUs were very likely to provide cost-savings if DFU incidence was decreased by at least 10% and/or the cost was less than $150 per person per year.

CONCLUSIONS

Low-cost DFU primary prevention efforts producing even small decreases in DFU incidence may provide the best opportunity for cost-savings, especially if focused on patients with neuropathy and/or PAD. Mobile phone-based reminders, self-identification of risk factors (ex. Ipswich touch test), and written brochures may be among such low-cost interventions that should be investigated for cost-savings potential.

Ambulation and independence among Veterans with nontraumatic bilateral lower-limb loss

In describing functional outcomes and independent living in a cohort of bilateral major amputees, we sought to provide current estimates of function and independence after a second major amputation in an elderly Veteran population with peripheral arterial disease and/or diabetes. After retrospectively reviewing and excluding the electronic health records of those failing to meet the inclusion criteria, we identified 40 patients with a history of unilateral major amputation who underwent a second major amputation during the defined study period. Of these, 43% (17) were bilateral transfemoral amputations (TFAs); bilateral transtibial amputations (TTAs) and TFA-TTA accounted for the rest (33% and 25%, respectively). Of the 19 (48%) patients who were ambulatory prior to bilateral amputation, only 2 (11%) remained ambulatory after the second amputation, while 17 (89%) patients lost ambulatory capabilities. Compared with those who were </=65 yr, those between 66 and 79 yr were 18% less likely to ambulate precontralateral amputation (p = 0.03). All patients with bilateral TFA were nonambulatory. Independence postcontralateral amputation decreased from 88% (35) to 53% (21). When data were available (58%), pre and post Functional Independence Measure scores showed a decrease in 74% of patients, while 22% showed an increase. In conclusion, bilateral lower-limb amputation among dysvascular Veterans is highly associated with a loss of ambulation.

An endovascular model of ischemic myopathy from peripheral arterial disease

OBJECTIVE

Peripheral arterial disease (PAD) is a significant age-related medical condition with limited pharmacologic options. Severe PAD, termed critical limb ischemia, can lead to amputation. Skeletal muscle is the end organ most affected by PAD, leading to ischemic myopathy and debility of the patient. Currently, there are not any therapeutics to treat ischemic myopathy, and proposed biologic agents have not been optimized owing to a lack of preclinical models of PAD. Because a large animal model of ischemic myopathy may be useful in defining the optimal dosing and delivery regimens, the objective was to create and to characterize a swine model of ischemic myopathy that mimics patients with severe PAD.

METHODS

Yorkshire swine (N = 8) underwent acute right hindlimb ischemia by endovascular occlusion of the external iliac artery. The effect of ischemia on limb function, perfusion, and degree of ischemic myopathy was quantified by weekly gait analysis, arteriography, hindlimb blood pressures, femoral artery duplex ultrasound scans, and histologic examination. Animals were terminated at 5 (n = 5) and 6 (n = 3) weeks postoperatively. Ossabaw swine (N = 8) fed a high-fat diet were used as a model of metabolic syndrome for comparison of arteriogenic recovery and validation of ischemic myopathy.

RESULTS

There was persistent ischemia in the right hindlimb, and occlusion pressures were significantly depressed compared with the untreated left hindlimb out to 6 weeks (systolic blood pressure, 31 ± 21 vs 83 ± 15 mm Hg, respectively; P = .0007). The blood pressure reduction resulted in a significant increase of ischemic myopathy in the gastrocnemius muscle in the treated limb. Gait analysis revealed a functional deficit of the right hindlimb immediately after occlusion that improved rapidly during the first 2 weeks. Peak systolic velocity values in the right common femoral artery were severely diminished throughout the entire study (P < .001), and the hemodynamic environment after occlusion was characterized by low and oscillatory wall shear stress. Finally, the internal iliac artery on the side of the ischemic limb underwent significant arteriogenic remodeling (1.8× baseline) in the Yorkshire but not in the Ossabaw swine model.

CONCLUSIONS

This model uses endovascular technology to produce the first durable large animal model of ischemic myopathy. Acutely (first 2 weeks), this model is associated with impaired gait but no tissue loss. Chronically (2-6 weeks), this model delivers persistent ischemia, resulting in ischemic myopathy similar to that seen in PAD patients. This model may be of use for testing novel therapeutics including biologic therapies for promoting neovascularization and arteriogenesis.

Cost-effectiveness of supervised exercise therapy compared with endovascular revascularization for intermittent claudication

Background

Current guidelines recommend supervised exercise therapy (SET) as the preferred initial treatment for patients with intermittent claudication. The availability of SET programmes is, however, limited and such programmes are often not reimbursed. Evidence for the long-term cost-effectiveness of SET compared with endovascular revascularization (ER) as primary treatment for intermittent claudication might aid widespread adoption in clinical practice.

Methods

A Markov model was constructed to determine the incremental costs, incremental quality-adjusted life-years (QALYs) and incremental cost-effectiveness ratio of SETversus ER for a hypothetical cohort of patients with newly diagnosed intermittent claudication, from the Dutch healthcare payer's perspective. In the event of primary treatment failure, possible secondary interventions were repeat ER, open revascularization or major amputation. Data sources for model parameters included original data from two RCTs, as well as evidence from the medical literature. The robustness of the results was tested with probabilistic and one-way sensitivity analysis.

Results

Considering a 5-year time horizon, probabilistic sensitivity analysis revealed that SET was associated with cost savings compared with ER (−€6412, 95 per cent credibility interval (CrI) –€11 874 to –€1939). The mean difference in effectiveness was −0·07 (95 per cent CrI −0·27 to 0·16) QALYs. ER was associated with an additional €91 600 per QALY gained compared with SET. One-way sensitivity analysis indicated more favourable cost-effectiveness for ER in subsets of patients with low quality-of-life scores at baseline.

Conclusion

SET is a more cost-effective primary treatment for intermittent claudication than ER. These results support implementation of supervised exercise programmes in clinical practice.

Cost-Effectiveness of Meningococcal Vaccination Among Men Who Have Sex With Men in New York City

BACKGROUND

To control an outbreak of invasive meningococcal disease (IMD) among men who have sex with men (MSM) in New York City, the New York City Department of Health and Mental Hygiene recommended vaccination of all HIV-infected MSM and at-risk HIV-uninfected MSM in October 2012.

METHODS

A decision-analytic model estimated the cost-effectiveness of meningococcal vaccination compared with no vaccination. Model inputs, including IMD incidence of 20.5 per 100,000 HIV-positive MSM (42% fatal) and 7.6 per 100,000 HIV-negative MSM (20% fatal), were from Department of Health and Mental Hygiene reported data and published sources. Outcomes included costs (2012 US dollars), IMD cases averted, IMD deaths averted, quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratios (ICERs; $/QALY). Scenarios with and without herd immunity were considered, and sensitivity analyses were performed on key inputs.

RESULTS

Compared with no vaccination, the targeted vaccination campaign averted an estimated 2.7 IMD cases, 1.0 IMD deaths, with an ICER of $66,000/QALY when herd immunity was assumed. Without herd immunity, vaccination prevented 1.1 IMD cases, 0.4 IMD deaths, with an ICER of $177,000/QALY. In one-way sensitivity analyses, variables that exerted the greatest influence on results in order of effect were the magnitude of herd immunity, IMD case fatality ratio, and IMD incidence. In probabilistic sensitivity analyses, at a cost-effectiveness threshold of $100,000/QALY, vaccination was preferred in 97% of simulations with herd immunity and 20% of simulations without herd immunity.

CONCLUSIONS

Vaccination during an IMD outbreak among MSM with and without HIV infection was projected to avert IMD cases and deaths and could be cost-effective depending on IMD incidence, case fatality, and herd immunity.

Expansion and angiogenic potential of mesenchymal stem cells from patients with critical limb ischemia

BACKGROUND

Critical limb ischemia (CLI) is a life- and limb-threatening condition affecting 1% to 10% of the population with peripheral arterial disease. Traditional revascularization options are not possible for up to 50% of CLI patients, in which case, the use of cellular therapies, such as bone marrow-derived mesenchymal stem cells (MSCs), hold great promise as an alternative revascularization therapy. However, no randomized, controlled phase 3 trials to date have demonstrated an improvement in limb salvage with cellular therapies. This may be due to poor cell quality (ie, inability to generate a sufficient number of angiogenic MSCs) or to the inadequate retention and viability of MSCs after delivery, or both. Because concerns remain about the expansion and angiogenic potential of autologous MSCs in the CLI population, the objective of this study was to examine the effect of our novel culture media supplement, pooled human platelet lysate (PL), in lieu of the standard fetal bovine serum (FBS), to improve the expansion potential of MSCs from CLI patients. We also characterized the in vitro angiogenic activity of MSCs from the tibia of amputated CLI limbs compared with MSCs from healthy donors.

METHODS

MSCs were obtained from the tibia of four CLI patients (ISC) and four ISC patients with diabetes mellitus (ISC+DM) undergoing major amputation. Healthy MSCs were aspirated from the iliac crest of four young and healthy donors. MSCs were isolated and expanded in culture with PL or FBS. MSCs from passage 3 to 6 were used for phenotypic marker expression and for adipogenic and osteogenic differentiation and were tested for their in vitro angiogenic activity on human microdermal endothelial cells. In parallel MSCs were cultured to passage 11 for population-doubling calculations.

RESULTS

MSCs from ISC and ISC+DM patients and from healthy patients exhibited appropriate expression of cell surface markers and differentiation capacity. Population doublings were significantly greater for PL-stimulated compared with FBS-stimulated MSCs in all groups. Biologically active amounts of angiogens were identified in the secretome of all MSCs without consistent trends among groups. PL expansion did not adversely affect the angiogenic activity of MSCs compared with FBS. The ISC and ISC+DM MSCs demonstrated angiogenic effects on endothelial cells similar to those of healthy and ISC MSCs.

CONCLUSIONS

PL promotes the rapid expansion of MSCs from CLI and healthy persons. Importantly, MSCs expanded from CLI patients demonstrate the desired angiogenic activity compared with their healthy counterparts. We conclude that autologous MSCs from CLI patients can be sufficiently expanded with PL and be expected to deliver requisite angiogenic effects in vivo. We expect the improved expansion of ISC and ISC+DM with PL to be helpful in improving the successful delivery of autologous MSCs to patients with CLI.

Preventable Complications Driving Rising Costs in Management of Patients with Critical Limb Ischemia

BACKGROUND

This study aimed to identify factors that drive increasing health-care costs associated with the management of critical limb ischemia in elective inpatients.

METHODS

Patients with a primary diagnosis code of critical limb ischemia (CLI) were identified from the 2001-2011 Nationwide Inpatient Sample. Demographics, CLI management, comorbidities, complications (bleeding, surgical site infection [SSI]), length of stay, and median in-hospital costs were reviewed. Statistical analysis was completed using Students' t-test and Mann-Kendall trend analysis. Costs are reported in 2011 US dollars corrected using the consumer price index.

RESULTS

From 2001 to 2011, there were a total of 451,823 patients who underwent open elective revascularization as inpatients for CLI. Costs to treat CLI increased by 63% ($12,560 in 2001 to $20,517 in 2011, P < 0.001 in trend analysis). Endovascular interventions were 20% more expensive compared with open surgery ($19,566 vs. $16,337, P < 0.001). Age, gender, and insurance status did not affect the cost of care. From 2001 to 2011, the number of patient comorbidities (7.56-12.40) and percentage of endovascular cases (13.4% to 27.4%) increased, accounting for a 6% annual increase in total cost despite decreased median length of stay (6 to 5 days). Patients who developed SSI had total costs 83% greater than patients without SSIs ($30,949 vs. $16,939; P < 0.001). Patients who developed bleeding complications had total costs 41% greater than nonbleeding patients ($23,779 vs. $16,821, P < 0.001). Overall, there was a 32% reduction in SSI rates but unchanged rates of bleeding complications during this period.

CONCLUSIONS

The cost of CLI treatment is increasing and driven by rising endovascular use, SSI, and bleeding in the in-patient population. Further efforts to reduce complications in this patient population may contribute to a reduction in health care-associated costs of treating CLI.

Cost-effectiveness of revascularization for limb preservation in patients with end-stage renal disease

BACKGROUND

Limb revascularization in patients with end-stage renal disease (ESRD) has been criticized because of the low rates of limb preservation and overall survival that characterize this patient population. We undertook a formal cost-utility analysis to evaluate the role of revascularization in the ESRD population.

METHODS

A probabilistic Markov model was used to simulate the clinical outcomes and long-term outcomes after six different strategies for the management of nonhealing foot wounds in patients with critical limb ischemia and ESRD. All scenarios considered all-cause mortality and major amputation for failure of limb salvage. Parameter estimates of the costs, clinical events, and functional outcomes used in the model were derived from primary data or published literature. Costs are reported in 2011 U.S. dollars.

RESULTS

Local wound care alone had the lowest long-term total cost of the management strategies evaluated; primary amputation had the highest. Purely endovascular intervention yielded the highest limb salvage rates. Endovascular intervention had a cost of $15,403 per additional year of ambulation beyond that by local wound care alone. Endovascular intervention had the potential for cost-savings (ie, better health benefits at lower cost) only with very high 1-year wound healing rates. The 5-year survival rates ranged from 17% to 34% in all management strategies.

CONCLUSIONS

Endovascular intervention may be a cost-effective alternative to local wound care alone for patients with ESRD and ischemic foot wounds, but with small marginal health benefits at considerable cost. Local wound care alone may be preferable to primary amputation.

The system of care for the diabetic foot: objectives, outcomes, and opportunities

Most cases of lower extremity limb loss in the United States occur among people with diabetes who have a diabetic foot ulcer (DFU). These DFUs and the associated limb loss that may occur lead to excess healthcare costs and have a large negative impact on mobility, psychosocial well-being, and quality of life. The strategies for DFU prevention and management are evolving, but the implementation of these prevention and management strategies remains challenging. Barriers to implementation include poor access to primary medical care; patient beliefs and lack of adherence to medical advice; delays in DFU recognition; limited healthcare resources and practice heterogeneity of specialists. Herein, we review the contemporary outcomes of DFU prevention and management to provide a framework for prioritizing quality improvement efforts within a resource-limited healthcare environment.

A cost-effectiveness analysis of infrainguinal bypass in the absence of great saphenous vein conduit

BACKGROUND

Good-quality great saphenous vein (GSV) is the preferred conduit for infrainguinal surgical revascularizations, but it is not available in all patients. We sought to identify the alternative conduit that would maximize cost-effectiveness in the context of infrapopliteal bypass for critical limb ischemia and nonhealing foot wounds.

METHODS

A Markov model was used to create a detailed simulation of 10-year outcomes in a hypothetical Edifoligide for the Prevention of Infrainguinal Vein Graft Failure (PREVENT) III-type patient cohort undergoing infrainguinal bypass for nonhealing foot wounds. The following management options were evaluated: (1) conservative therapy (local wound care, amputation as needed); (2) primary amputation; (3) bypass with autologous alternative vein (AAV), including arm or lesser saphenous vein; (4) bypass with GSV <3 mm in diameter; (5) bypass with polytetrafluoroethylene (PTFE); (6) cryopreserved venous allograft; and (7) cryopreserved arterial allograft. Estimates of 10-year total costs were incorporated into the model. Cost-effectiveness was measured in terms of incremental United States dollars per additional year of ambulation.

RESULTS

Bypass with AAV had the highest effectiveness as measured in median years of ambulation. After primary amputation, bypass with PTFE had the lowest total costs. With incremental cost-effectiveness ratios of $5325 and $21,228, bypass with PTFE or AAV appeared to be cost-effective alternatives to conservative therapy for nonhealing ischemic wounds. Primary amputation, GSV <3 mm, and allograft options were dominated (ie, more costly and less effective). Primary amputation was weakly dominated.

CONCLUSIONS

Bypass with PTFE or AAV appears to be a cost-effective option for the management of critical limb ischemia and nonhealing foot wounds when good-quality GSV is not available.