Cost-effectiveness in the contemporary management of critical limb ischemia with tissue loss

Efficacy and Durability of Percutaneous Deep Vein Arterialization: A Systematic Review

BACKGROUND

Endovascular deep vein arteriaization (DVA) is a novel technique aimed at salvaging peripheral arterial disease unamenable to conventional surgical intervention. This study aims to review contemporary literature on the efficacy, safety, and durability of DVA on patients with no-option critical limb ischemia (NO-CLI).

METHODS

The study was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement, using predefined search terms of "percutaneous deep vein arterialization" or "percutaneous deep venous arterialization" in PubMed, Web of Sciences, OvidSP, and Embase. Only studies with 5 or more patients were included, and studies involving open or hybrid DVA were excluded. The primary outcomes included technical success and primary amputation rates. Secondary outcomes included rates of wound healing, complication, reintervention, and all-cause mortality.

RESULTS

Ten studies encompassing a total of 233 patients were included. Patients were primarily those deemed to have NO-CLI. The median follow-up period was 12 months (range 1-63 months). The technical success rate was 97% (95% confidence interval [CI] 96.2%-97.9%) and the major amputation rate was 21.8% (95% 21.1%-22.4%). The wound healing rate was 69.5% (95% CI 67.9-71.0%), complication rate was 13.8% (95% CI 11.7%-15.9%), reintervention rate was 37.4% (95% CI 34.9%-39.9%), and all-cause mortality rate was 15.7% (95% CI 14.1%-17.2%).

CONCLUSIONS

Our study showed that endovascular DVA is safe for patients with NO-CLI. Nonetheless, studies were small with follow-up period of less than 1 year. There is currently lack of level 1 evidence to recommend routine use in patients with NO-CLI.

Secondary interventions following open vs endovascular revascularization for chronic limb threatening ischemia in the BEST-CLI trial

OBJECTIVES

Patients undergoing revascularization for chronic limb-threatening ischemia experience a high burden of target limb reinterventions. We analyzed data from the Best Endovascular versus Best Surgical Therapy in Patients with Critical Limb Ischemia (BEST-CLI) randomized trial comparing initial open bypass (OPEN) and endovascular (ENDO) treatment strategies, with a focus on reintervention-related study endpoints.

METHODS

In a planned secondary analysis, we examined the rates of major reintervention, any reintervention, and the composite of any reintervention, amputation, or death by intention-to-treat assignment in both trial cohorts (cohort 1 with suitable single-segment great saphenous vein [SSGSV], n = 1434; cohort 2 lacking suitable SSGSV, n = 396). We also compared the cumulative number of major and all index limb reinterventions over time. Comparisons between treatment arms within each cohort were made using univariable and multivariable Cox regression models.

RESULTS

In cohort 1, assignment to OPEN was associated with a significantly reduced hazard of a major limb reintervention (hazard ratio [HR], 0.37; 95% confidence interval [CI], 0.28-0.49; P < .001), any reintervention (HR, 0.63; 95% CI, 0.53-0.75; P < .001), or any reintervention, amputation, or death (HR, 0.68; 95% CI, 0.60-0.78; P < .001). Findings were similar in cohort 2 for major reintervention (HR, 0.53; 95% CI, 0.33-0.84; P = .007) or any reintervention (HR, 0.71; 95% CI, 0.52-0.98; P = .04). In both cohorts, early (30-day) limb reinterventions were notably higher for patients assigned to ENDO as compared with OPEN (14.7% vs 4.5% of cohort 1 subjects; 16.6% vs 5.6% of cohort 2 subjects). The mean number of major (mean events per subject ratio [MR], 0.45; 95% CI, 0.34-0.58; P < .001) or any target limb reinterventions (MR, 0.67; 95% CI, 0.57-0.80; P < .001) per year was significantly less in the OPEN arm of cohort 1. The mean number of reinterventions per limb salvaged per year was lower in the OPEN arm of cohort 1 (MR, 0.45; 95% CI, 0.35-0.57; P < .001 and MR, 0.66; 95% CI, 0.55-0.79; P < .001 for major and all, respectively). The majority of index limb reinterventions occurred during the first year following randomization, but events continued to accumulate over the duration of follow-up in the trial.

CONCLUSIONS

Reintervention is common following revascularization for chronic limb-threatening ischemia. Among patients deemed suitable for either approach, initial treatment with open bypass, particularly in patients with available SSGSV conduit, is associated with a significantly lower number of major and minor target limb reinterventions.

Contemporary outcomes of initial treatment strategy of endovascular intervention or bypass in patients with critical limb ischemia

OBJECTIVE

The optimal management for revascularization after critical limb ischemia (CLI) is controversial due to limited studies comparing long-term results of endovascular and open techniques. This study compares long-term outcomes after initial management of CLI via lower extremity bypass (LEB) and percutaneous vascular intervention (PVI).

METHODS

This retrospective cohort study investigates outcomes of patients who underwent endovascular or open surgical management for CLI at a single institution from 2013-2018. All patients with diagnosis of CLI were included and separated based on initial therapy of PVI or LEB. Demographic, procedural, and follow-up data were assessed. Primary endpoints included major adverse limb events (MALE), specifically the need for major amputation and reintervention. Secondary endpoints included mortality at 30 days and one year. A multivariable Cox Proportional Hazard regression model was used to assess the relationship between Surgery group and time to MALE/death while controlling for confounding variables.

RESULTS

This study identified 338 patients with an initial diagnosis of CLI who underwent either LEB (n = 108, 32%) or PVI (n = 230, 68%). The average age was 71.4, 54.4% were male, 30% were African American, 53.6% were diabetic, and 93.2% had hypertension. Patients who underwent LEB were more predominantly smokers (p = .003) and less predominantly on dialysis at time of surgery (p = .01). Re-intervention rates in the bypass group (11%) were not significantly different than the PVI group (9%; p = .95). In the bypass group, 20 (19%) patients had a major amputation with a median time of 189.5 days compared to 23 (10%) patients at a median time of 113 days in the PVI group; however, this difference was not significant (p = .16). There was no significant difference in 1-year mortality between the LEB (2%) and PVI group (4%; p = .2). The cumulative incidence of MALE/death at 30 days was 4.0% in the bypass group and 3.7% in the PVI group (p = .2). Incidences of MALE/death were 21.1% and 48.5% in the bypass group and 19.7 and 45.9% in the PVI group at one and 2 years, respectively. Intervention type was not found to be significantly associated with MALE/death after controlling for possible confounders (HR = 0.82, p = .43).

CONCLUSIONS

In the initial management of CLI, there is no significant difference in long-term outcomes in terms of major amputation, need for reintervention, limb-salvage, and 1-year mortality.

Outcomes and use of healthcare resources after an intervention for chronic limb-threatening ischaemia

BACKGROUND

The fate of patients with chronic limb-threatening ischaemia undergoing revascularization or a primary amputation is unclear. The aim of this study was to assess the postoperative outcomes and post-procedural healthcare resource use/costs over 1 year after revascularization or a primary amputation for chronic limb-threatening ischaemia.

METHODS

The UK Kent Integrated Dataset, which links primary, community, and secondary care for 1.6 million people, was interrogated. All patients with a new diagnosis of chronic limb-threatening ischaemia undergoing revascularization or a major amputation between January 2016 and January 2019 (3 years) were identified. Postoperative events across all healthcare settings and post-procedure healthcare resource use were analysed over 1 year (until the end of 2019).

RESULTS

Overall, 4252 patients with a new diagnosis of chronic limb-threatening ischaemia were identified (65 per cent were male and the mean age was 73 years) between January 2016 and January 2019, of whom 579 (14 per cent) underwent an intervention (studied population); 296 (7 per cent) had an angioplasty, 75 (2 per cent) had bypass surgery, 141 (3 per cent) had a primary major lower limb amputation, 11 had a thrombo-embolectomy (0.3 per cent), and 56 had an endarterectomy (1.3 per cent). Readmissions (median of 2) were similar amongst different procedures within 1 year; bypass surgery was associated with more hospital appointments (median of 4 versus 2; P = 0.002). Patients undergoing a primary amputation had the highest number of cardiovascular events and 1-year mortality. In a linear regression model, index procedure type and Charlson co-morbidity index score were not predictors of appointments in primary/secondary care, community care visits, or readmissions after discharge. There were no statistically significant differences regarding post-procedural healthcare costs between procedures over 1 year.

CONCLUSION

Revascularization is not associated with more hospital, primary/community care appointments or increased post-procedural healthcare costs over 1 year when compared with primary amputation, in people with chronic limb-threatening ischaemia.

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.

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.

A Systematic Review of Cost-Utility Analyses in Chronic Limb-Threatening Ischemia

BACKGROUND

To review and describe the available literature on cost-utility analysis of revascularization and non-revascularization treatment approaches in chronic limb-threatening ischemia.

METHODS

A systematic review was performed on cost-utility analysis studies evaluating revascularization (open surgery or endovascular), major lower extremity amputation, or conservative management in adult chronic limb-threatening ischemia patients. Six bibliographic databases and online registries were searched for English language articles up to August 2021. The outcome for cost-utility analysis was quality-adjusted in life years. Procedures were compared using incremental cost-effectiveness ratios which were converted to 2021 United States dollars. Study reporting quality was assessed using the 2022 Consolidated Health Economic Evaluation Reporting Standards statement. The study was registered in International Prospective Register of Systematic Reviews (CRD42021273602).

RESULTS

Three trial-based and five model-based studies were included for review. Studies met between 14/28 and 20/28 criteria of the Consolidated Health Economic Evaluation Reporting Standards CHEERS statement. Only one study was written according to standardized reporting guidelines. Most studies evaluated infrainguinal disease, and adopted a health care provider perspective. There was a large variation in the incremental cost-effectiveness ratios presented across studies. Open surgical revascularization (incremental cost-effectiveness ratios: $3,678, $58,828, and $72,937), endovascular revascularization (incremental cost-effectiveness ratios: $52,036, $125,329, and $149,123), and mixed open or endovascular revascularization (incremental cost-effectiveness ratio: $8,094) maybe more cost-effective than conservative management.

CONCLUSIONS

The application of cost-utility analyses in chronic limb-threatening ischemia is in its infancy. Revascularization in infrainguinal disease may be favored over major lower extremity amputation or conservative management. However, data is inadequate to support recommendations for a specific treatment. This review identifies short and long-term considerations to address the current state of evidence. Cost-utility analysis is an important tool in healthcare policy and should be encouraged amongst the vascular surgical community.

A narrative review of the epidemiology and economics of chronic wounds

Chronic wounds have a debilitating effect on the quality of life of many individuals, and the large economic impact on health system budgets warrants greater attention in policy making and condition management than is currently evident. The aim of this narrative review is to summarize the nature and extent of the chronic wound problem that confronts health systems across the world. The first section is used to highlight the underlying epidemiology relating to chronic wounds, while the second explores the economic costs associated with them and the relative efficiency of measures designed to manage them.

Cost-effectiveness analysis of domiciliary topical sevoflurane for painful leg ulcers

Objectives

The general anesthetic sevoflurane is being repurposed as a topical analgesic for painful chronic wounds. We conducted a Bayesian cost-effectiveness analysis (CEA) comparing the addition of domiciliary topical sevoflurane to conventional analgesics (SEVOFLURANE, n = 38) versus conventional analgesics alone (CONVENTIONAL, n = 26) for the treatment of nonrevascularizable painful leg ulcers in an outpatient Pain Clinic of a Spanish tertiary hospital.

Methods

We used real-world data collected from charts to conduct this CEA from a public healthcare perspective and with a one-year time horizon. Costs of analgesics, visits and admissions were considered, expressed in €2016. Analgesic effectiveness was measured with SPID (Sum of Pain Intensity Difference). A Bayesian regression model was constructed, including “treatment” and baseline characteristics for patients (“arterial hypertension”) and ulcers (“duration”, “number”, “depth”, “pain”) as covariates. The findings were summarized as a cost-effectiveness plane and a cost-effectiveness acceptability curve. One-way sensitivity analyses, a re-analysis excluding those patients who died or suffered from leg amputation, and an extreme scenario analysis were conducted to reduce uncertainty.

Results

Compared to CONVENTIONAL, SEVOFLURANE was associated with a 46% reduction in costs, and the mean incremental effectiveness (28.15±3.70 effectiveness units) was favorable to SEVOFLURANE. The estimated probability for SEVOFLURANE being dominant was 99%. The regression model showed that costs were barely influenced by any covariate, whereas effectiveness was noticeably influenced by “treatment”. All sensitivity analyses showed the robustness of the model, even in the extreme scenario analysis against SEVOFLURANE.

Conclusions

SEVOFLURANE was dominant over CONVENTIONAL as it was less expensive and much more effective.

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.

Healthcare disparities in vascular surgery: A critical review

Health disparities in vascular surgical care have existed for decades. Persons categorized as Black undergo a nearly twofold greater risk-adjusted rate of leg amputations. Persons categorized as Black, Latinx, and women have hemodialysis initiated via autogenous fistula less often than male persons categorized as White. Persons categorized as Black, Latino, Latina, or Latinx, and women are less likely to undergo carotid endarterectomy for symptomatic carotid stenosis and repair of abdominal aortic aneurysms. New approaches are needed to address these disparities. We suggest surgeons use data to identify groups that would most benefit from medical care and then partner with community organizations or individuals to create lasting health benefits. Surgeons alone cannot rectify the structural inequalities present in American society. However, all surgeons should contribute to ensuring that all people have access to high-quality vascular surgical care.

National Trends for Peripheral Artery Disease and End Stage Renal Disease From the National Inpatient Sample Database

Peripheral artery disease (PAD), and subsequent chronic limb-threatening ischemia (CLTI), are frequently encountered among patients with end-stage renal disease (ESRD). Their coexistence is less favorable in comparison to patients with ESRD alone. We sought to investigate trends, comorbidities, determinants for cost, and prognostic outcomes in patients with concomitant ESRD and PAD. A retrospective analysis was performed using data from the National Inpatient Sample database from the years 2005-2014. ICD-9 codes were used to identify patients with diagnoses of PAD, CLTI, and ESRD. Pearson’s Chi-square, T-test, ANOVA, and multivariate binary logistic regression were used in this analysis. 7,214,843 patients with ESRD were identified. Of these, 123,499 patients were diagnosed with PAD and 102,447 with CLTI. Compared to ESRD alone, mortality rates increased with PAD and CLTI (5.7% vs. 13.9% vs. 15.9%, P < 0.001). Length of stay in days (7.3 vs. 10.2 vs. 11.1, P < 0.001) and in-hospital costs (59,872 vs. 85,866 vs. 89,016, P < 0.001) were higher with PAD and CLTI, respectively. CLTI demonstrated the highest independent predictor of mortality [OR = 6.93 (6.43-7.46), P < 0.001]. A decreasing trend in the rate of PAD (2005: 1.9% vs. 2014: 1.4%, P < 0.001) and CLTI (2005: 1.6% vs. 2014: 1.1%, P < 0.001) was noted. The presence of coexisting PAD, and furthermore CLTI, in patients with ESRD significantly raised in-hospital mortality, cost, and length of stay. A negative trend in rates of PAD and CLTI were observed. Proactive identification of this high-risk population may lead to accurate diagnosis and tailored therapeutic strategies.

Randomized, Double-Blind, Placebo-Controlled Trial to Evaluate Safety and Therapeutic Efficacy of Angiogenesis Induced by Intraarterial Autologous Bone Marrow-Derived Stem Cells in Patients with Severe Peripheral Arterial Disease

PURPOSE

To evaluate safety and efficacy of angiogenesis induced by intraarterial autologous bone marrow-derived stem cell (BMSC) injection in patients with severe peripheral arterial disease (PAD).

MATERIALS AND METHODS

Eighty-one patients with severe PAD (77 men), including 56 with critical limb ischemia (CLI) and 25 with severe claudication, were randomized to receive sham injection (group A) or intraarterial BMSC injection at the site of occlusion (group B). Primary endpoints included improvement in ankle-brachial index (ABI) of > 0.1 and transcutaneous pressure of oxygen (TcPO₂) of > 15% at mid- and lower foot at 6 mo. Secondary endpoints included relief from rest pain, > 30% reduction in ulcer size, and reduction in major amputation in patients with CLI and > 50% improvement in pain-free walking distance in patients with severe claudication.

RESULTS

Technical success was achieved in all patients, without complications. At 6 mo, group B showed more improvements in ABI of > 0.1 (35 of 41 [85.37%] vs 13 of 40 [32.50%]; P < .0001) and TcPO₂ of > 15% at the midfoot (35 of 41 [85.37%] vs 17 of 40 [42.50%]; P = .0001] and lower foot (37 of 41 [90.24%] vs 19 of 40 [47.50%]; P < .0001). No patients with CLI underwent major amputation in group B, compared with 4 in group A (P = .0390). No significant difference was observed in relief from rest pain or > 30% reduction in ulcer size among patients with CLI or in > 50% improvement in pain-free walking distance among patients with severe claudication.

CONCLUSIONS

Intraarterial delivery of autologous BMSCs is safe and effective in the management of severe PAD.

Impact of prior endovascular interventions on outcomes of lower limb bypass surgery: A systematic review and meta-analysis

The aim of this meta-analysis was to evaluate the mortality, amputation and complication rates in patients with peripheral lower limb arterial disease undergoing bypass surgery with or without a prior history of endovascular operation. A systematic literature screen was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines on four academic databases, Medline, Scopus, Embase and Cochrane Central Register of Controlled Trials. Out of 1,072 records, six articles involving 11,420 patients (mean age, 68.1±2.0 years) met the inclusion criteria. The findings presented a 2b level of evidence (i.e. overall evidence represents data from individual cohort study or low quality randomized controlled trials) and suggested lower mortality, amputation and complication rates for patients undergoing bypass surgery without any history of endovascular operation, compared with those with a history of prior endovascular operation. Moreover, a random-effect meta-analysis suggested a small, positive reduction in mortality (Hedge's g=0.08), amputation (Hedge's g=0.18) and complication rates (Hedge's g=0.05) for patients undergoing bypass surgery without any history of endovascular operation. Nevertheless, owing to the scarcity of high-quality data, further studies and randomized clinical trials are needed to confirm these effects.

Dehydrated human amnion and chorion allograft versus standard of care alone in treatment of Wagner 1 diabetic foot ulcers: a trial-based health economics study

AIMS

The aim of this health economics study was to estimate the cost-utility of an aseptically processed, dehydrated human amnion and chorion allograft (dHACA) plus standard of care (SOC) (group 1) versus SOC alone (group 2) based on a published randomized controlled trial in which patients who had an eligible Wagner 1 diabetic foot ulcer wound were randomized to either of these treatments.

MATERIALS AND METHODS

A Markov microsimulation was used to project trial results out to a 1-year horizon time with a third-party payer perspective. The starting health state was an unhealed non-infected ulcer with other health states of healed ulcer, infected non-healed ulcer, cellulitis, osteomyelitis, and absorbing states of dead or amputation. All patients started with unhealed non-infected ulcers at cycle 0. Costs were incurred by patients for procedures at hospital outpatient wound care provider-based departments (PBDs) and hospitals (if complications occurred) and were calculated using time-based activity costing methods. Effectiveness units were quality-adjusted life years (QALYs) computed from literature utility values. One-way and probabilistic sensitivity analysis (PSA) were also conducted.

RESULTS

After 1 year, the calculated incremental cost-effectiveness ratio (ICER) for group 1 versus group 2 was -$4,373 with group 1 (dHACA) being dominant over group 2 (SOC). PSA demonstrated that group 1 had 69.2% lower cost values with increased positive incremental effectiveness for 94.9% of values. A willingness to pay (WTP) curve showed that about 92% of interventions were cost effective for group 1 when $50,000 was paid.

CONCLUSIONS

The results of this study demonstrated that dHACA added to SOC compared to SOC alone was extremely cost-effective in the defined trial population.

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.

The Role of Lower Extremity Amputation in Chronic Limb-Threatening Ischemia

Chronic limb-threatening ischemia (CLTI) is a severe form of peripheral artery disease associated with high rates of limb loss. The primary goal of treatment in CLTI is limb salvage via revascularization. Multidisciplinary teams provide improved care for those with CLTI and lead to improved limb salvage rates. Not all patients are candidates for revascularization, and a subset will require major amputation. This article highlights the role of amputations in the management of CLTI, and describes the patients who should be offered primary amputation.

Defining the 90-day cost structure of lower extremity revascularization for alternative payment model assessment

BACKGROUND

The U.S. healthcare system is undergoing a broad transformation from the traditional fee-for-service model to value-based payments. The changes introduced by the Medicare Quality Payment Program, including the establishment of Alternative Payment Models, ensure that the practice of vascular surgery is likely to face significant reimbursement changes as payments transition to favor these models. The Society for Vascular Surgery Alternative Payment Model taskforce was formed to explore the opportunities to develop a physician-focused payment model that will allow vascular surgeons to continue to deliver the complex care required for peripheral arterial disease (PAD).

METHODS

A financial analysis was performed based on Medicare beneficiaries who had undergone qualifying index procedures during fiscal year 2016 through the third quarter of 2017. Index procedures were defined using a list of Healthcare Common Procedural Coding (HCPC) procedure codes that represent open and endovascular PAD interventions. Inpatient procedures were mapped to three diagnosis-related group (DRG) families consistent with PAD conditions: other vascular procedures (codes, 252-254), aortic and heart assist procedures (codes, 268, 269), and other major vascular procedures (codes, 270-272). Patients undergoing outpatient or office-based procedures were included if the claims data were inclusive of the HCPC procedure codes. Emergent procedures, patients with end-stage renal disease, and patients undergoing interventions within the 30 days preceding the index procedure were excluded. The analysis included usage of postacute care services (PACS) and 90-day postdischarge events (PDEs). PACS are defined as rehabilitation, skilled nursing facility, and home health services. PDEs included emergency department visits, observation stays, inpatient readmissions, and reinterventions.

RESULTS

A total of 123,180 cases were included. Of these 123,180 cases, 82% had been performed in the outpatient setting. The Medicare expenditures for all periprocedural services provided at the index procedure (ie, professional, technical, and facility fees) were higher in the inpatient setting, with an average reimbursement per index case of $18,755, $34,600, and $25,245 for DRG codes 252 to 254, DRG codes 268 and 269, and DRG codes 270 to 272, respectively. Outpatient facility interventions had an average reimbursement of $11,458, and office-based index procedures had costs of $11,533. PACS were more commonly used after inpatient index procedures. In the inpatient setting, PACS usage and reimbursement were 58.6% ($5338), 57.2% ($4192), and 55.9% ($5275) for DRG codes 252 to 254, DRG codes 268 and 269, and DRG codes 270 to 272, respectively. Outpatient facility cases required PACS for 13.7% of cases (average cost, $1352), and office-based procedures required PACS in 15% of cases (average cost, $1467). The 90-day PDEs were frequent across all sites of service (range, 38.9%-50.2%) and carried significant costs. Readmission was associated with the highest average PDE expenditure (range, $13,950-$18.934). The average readmission Medicare reimbursement exceeded that of the index procedures performed in the outpatient setting.

CONCLUSIONS

The cost of PAD interventions extends beyond the index procedure and includes relevant spending during the long postoperative period. Despite the analysis challenges related to the breadth of vascular procedures and the site of service variability, the data identified potential cost-saving opportunities in the management of costly PDEs. Because of the vulnerability of the PAD patient population, alternative payment modeling using a bundled value-based approach will require reallocation of resources to provide longitudinal patient care extending beyond the initial intervention.

Bayesian Regression Model for a Cost-Utility and Cost-Effectiveness Analysis Comparing Punch Grafting Versus Usual Care for the Treatment of Chronic Wounds

Punch grafting is a traditional technique used to promote epithelialization of hard-to-heal wounds. The main purpose of this observational study was to conduct a cost-utility analysis (CUA) and a cost-effectiveness analysis (CEA) comparing punch grafting (n = 46) with usual care (n = 34) for the treatment of chronic wounds in an outpatient specialized wound clinic from a public healthcare system perspective (Spanish National Health system) with a three-month time horizon. CUA outcome was quality-adjusted life years (QALYs) calculated from EuroQoL-5D, whereas CEA outcome was wound-free period. One-way sensitivity analyses, extreme scenario analysis, and re-analysis by subgroups were conducted to fight against uncertainty. Bayesian regression models were built to explore whether differences between groups in costs, wound-free period, and QALYs could be explained by other variables different to treatment. As main results, punch grafting was associated with a reduction of 37% in costs compared to usual care, whereas mean incremental utility (0.02 ± 0.03 QALYs) and mean incremental effectiveness (7.18 ± 5.30 days free of wound) were favorable to punch grafting. All sensitivity analyses proved the robustness of our models. To conclude, punch grafting is the dominant alternative over usual care because it is cheaper and its utility and effectiveness are greater.

BEST Endovascular Versus Best Surgical Therapy in Patients with Critical Limb Ischemia (BEST-CLI) Trial

The Best Endovascular versus Best Surgical Therapy in Patients with Critical Limb Ischemia trial (BEST-CLI) is an international, prospective, multicentre, multidisciplinary and pragmatic, open-label, superiority-based, comparative-effectiveness randomised controlled trial designed to address the knowledge gap in choosing the appropriate therapy for the treatment of critical limb ischaemia (CLI). This study compares the effectiveness of the best available surgical treatment with the best available endovascular treatment in adults with CLI who are eligible for both treatment options. The study has completed its enrolment phase and patients included in the study are currently being followed up to 50 months. Results of the study promise to provide us with answers to several questions regarding treatment options for patients with CLI, more recently referred to as chronic limb-threatening ischaemia.

Diagnostic and Therapeutic Approaches in the Management of Infrapopliteal Arterial Disease

Chronic limb-threatening ischemia represents end-stage peripheral artery disease. It is underdiagnosed; it relies on clinical symptoms and traditional noninvasive tests, which significantly underestimate the severity of disease. Innovative techniques, approaches, technologies, and risk-assessment tools have significantly improved our ability to treat these patients and to better understand their complex disease process. For patients with chronic limb-threatening ischemia considered without options, the reengineering of deep venous arterialization procedures has shown promising results. Finally, the creation of interactive and multidisciplinary teams in centers of excellence is of paramount importance to significantly improve the care and outcomes of these patients.

Analysis of the Peri-Operative Cost of Non-Traumatic Major Lower Extremity Amputation in Jordan

Purpose

Non-traumatic major lower extremity amputation (NMLEA) is a commonly performed procedure that presents a substantial cost burden. Patients who undergo NMLEA are usually considered as a high-risk group with significant comorbidities, which translates into a protracted peri-operative course and increased health-care costs. The primary aim of this study was therefore to perform a contemporary peri-operative cost analysis of NMLEA performed in our center. We are a major tertiary referral hospital that provides vascular surgery services to the entire northern counties in Jordan. We also aimed to assess the various factors that influence the cost of NMLEA in less economically developed countries.

Methods

Records of all patients who underwent NMLEA at King Abdullah University Hospital between January 2012 and December 2017 were retrieved. Total inpatient cost was calculated and analyzed against different patients' variables.

Results

A total of 140 patients underwent NMLEA between 2012 and 2017 in our facility. Below-knee amputations accounted for 110 cases, while above-knee amputations included 30 patients. Approximately two-thirds of the cases (61.4%) were males, with average age of the patients being approximately 62.9 years. The commonest comorbidities were diabetes mellitus and hypertension, which were recorded in 89.3% and 80.3% of the patients, respectively. The average operative time was 133.0 ± 10.8 mins, and the average length of stay (LOS) was 6.7±0.4 days. The mean cost for amputations was 4904.7± 429.3 United States dollars. Multiple linear regression analysis demonstrated that LOS and admission-to-operation time were the independent predictors of cost.

Conclusion

Delayed amputations and prolonged LOS remain the most important determinants for the peri-operative cost of NMLEA. When amputation is deemed inevitable, an expedited multidisciplinary approach may possibly reduce undue delays and result in cost-effective delivery of this age-old remedy.

Evaluation of machine learning methodology for the prediction of healthcare resource utilization and healthcare costs in patients with critical limb ischemia-is preventive and personalized approach on the horizon?

Background

Critical limb ischemia (CLI) is a severe stage of peripheral arterial disease and has a substantial disease and economic burden not only to patients and families, but also to the society and healthcare systems. We aim to develop a personalized prediction model that utilizes baseline patient characteristics prior to CLI diagnosis to predict subsequent 1-year all-cause hospitalizations and total annual healthcare cost, using a novel Bayesian machine learning platform, Reverse Engineering Forward Simulation™ (REFS™), to support a paradigm shift from reactive healthcare to Predictive Preventive and Personalized Medicine (PPPM)-driven healthcare.

Methods

Patients ≥ 50 years with CLI plus clinical activity for a 6-month pre-index and a 12-month post-index period or death during the post-index period were included in this retrospective cohort of the linked Optum-Humedica databases. REFS™ built an ensemble of 256 predictive models to identify predictors of all-cause hospitalizations and total annual all-cause healthcare costs during the 12-month post-index interval.

Results

The mean age of 3189 eligible patients was 71.9 years. The most common CLI-related comorbidities were hypertension (79.5%), dyslipidemia (61.4%), coronary atherosclerosis and other heart disease (42.3%), and type 2 diabetes (39.2%). Post-index CLI-related healthcare utilization included inpatient services (14.6%) and ≥ 1 outpatient visits (32.1%). Median annual all-cause and CLI-related costs per patient were $30,514 and $2196, respectively. REFS™ identified diagnosis of skin and subcutaneous tissue infections, cellulitis and abscess, use of nonselective beta-blockers, other aftercare, and osteoarthritis as high confidence predictors of all-cause hospitalizations. The leading predictors for total all-cause costs included region of residence and comorbid health conditions including other diseases of kidney and ureters, blindness of vision defects, chronic ulcer of skin, and chronic ulcer of leg or foot.

Conclusions

REFS™ identified baseline predictors of subsequent healthcare resource utilization and costs in CLI patients. Machine learning and model-based, data-driven medicine may complement physicians' evidence-based medical services. These findings also support the PPPM framework that a paradigm shift from post-diagnosis disease care to early management of comorbidities and targeted prevention is warranted to deliver a cost-effective medical services and desirable healthcare economy.

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.

Cost-effectiveness of the treatments for critical limb ischemia in the elderly population

OBJECTIVE

The treatment of critical limb ischemia (CLI), with the intention to prevent limb loss, is often an intensive and expensive therapy. The aim of this study was to examine the cost-effectiveness of endovascular and conservative treatment of elderly CLI patients unsuitable for surgery.

METHODS

In this prospective observational cohort study, data were gathered in two Dutch peripheral hospitals. CLI patients aged 70 years or older were included in the outpatient clinic. Exclusion criteria were malignant disease, lack of language skills, and cognitive impairment; 195 patients were included and 192 patients were excluded. After a multidisciplinary vascular conference, patients were divided into three treatment groups (endovascular revascularization, surgical revascularization, or conservative therapy). Subanalyses based on age were made (70-79 years and ≥80 years). The follow-up period was 2 years. Cost-effectiveness of endovascular and conservative treatment was quantified using incremental cost-effectiveness ratios (ICERs) in euros per quality-adjusted life-years (QALYs).

RESULTS

At baseline, patients allocated to surgical revascularization had better health states, but the health states of endovascular revascularization and conservative therapy patients were comparable. With an ICER of €38,247.41/QALY (∼$50,869/QALY), endovascular revascularization was cost-effective compared with conservative therapy. This is favorable compared with the Dutch applicable threshold of €80,000/QALY (∼$106,400/QALY). The subanalyses also established that endovascular revascularization is a cost-effective alternative for conservative treatment both in patients aged 70 to 79 years (ICER €29,898.36/QALY; ∼$39,765/QALY) and in octogenarians (ICER €56,810.14/QALY; ∼$75,557/QALY).

CONCLUSIONS

Our study has shown that endovascular revascularization is cost-effective compared with conservative treatment of CLI patients older than 70 years and also in octogenarians. Given the small absolute differences in costs and effects, physicians should also consider individual circumstances that can alter the outcome of the intervention. Cost-effectiveness remains one of the aspects to take into consideration in making a clinical decision.

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.

SDF-1 plasmid treatment for patients with peripheral artery disease (STOP-PAD): Randomized, double-blind, placebo-controlled clinical trial

The efficacy of biologic therapies in critical limb ischemia (CLI) remains elusive, in part, due to limitations in trial design and patient selection. Using a novel design, we examined the impact of complementing revascularization therapy with intramuscular JVS-100 – a non-viral gene therapy that activates endogenous regenerative repair pathways. In this double-blind, placebo-controlled, Phase 2B trial, we randomized 109 patients with CLI (Rutherford class V or VI) to 8 mg or 16 mg intramuscular injections of placebo versus JVS-100. Patients were eligible if they persistently had reduced forefoot perfusion, by toe–brachial index (TBI) or skin perfusion pressure (SPP), following successful revascularization with angiographic demonstration of tibial arterial flow to the ankle. The primary efficacy end point was a 3-month wound healing score assessed by an independent wound core laboratory. The primary safety end point was major adverse limb events (MALE). Patients’ mean age was 71 years, 33% were women, 79% had diabetes, and 8% had end-stage renal disease. TBI after revascularization was 0.26, 0.27, and 0.26 among the three groups (placebo, 8 mg, and 16 mg injections, respectively). Only 26% of wounds completely healed at 3 months, without any differences between the three groups (26.5%, 26.5%, and 25%, respectively). Similarly, there were no significant changes in TBI at 3 months. Three (2.8%) patients died and two (1.8%) had major amputations. Rates of MALE at 3 months were 8.8%, 20%, and 8.3%, respectively. While safe, JVS-100 failed to improve wound healing or hemodynamic measures at 3 months. Only one-quarter of CLI wounds healed at 3 months despite successful revascularization, highlighting the need for additional research in therapies that can improve microcirculation in these patients. ClinicalTrials.gov Identifier: NCT02544204

Why Is Calculating the "True" Cost-to-Heal Wounds So Challenging?

Objective: The aim of the study was to illustrate the differences in the cost-to-heal wounds using two methods: (1) reimbursement-based costing and (2) activity-based costing (ABC). Approach: A small cohort (100 patients with multiple wounds of which 1 was a diabetic foot ulcer [DFU]) was randomly selected from the U.S. Wound Registry to be representative of all patients with DFUs in the registry. Unit costs, resource utilization, and total costs were estimated through both methods. For the ABC method, costs were calculated in ranges: low, mid, and high. Results: The mean cost to heal through the reimbursement-based costing method was US$20,618 compared with a range of US$18,627-US$35,185 for the ABC method. About 20% of DFUs that cost US$10,000-US$20,000 to heal with the reimbursement-based costing method shifted to much higher values based on the ABC method. The percentage of costs represented by inpatient procedures was much lower for the reimbursement method compared with the ABC method. Innovation and Conclusions: The results show that (1) the "true" cost-to-heal DFUs strongly depend on the method used to calculate the costs, and (2) the reimbursement-based costing method may not accurately reflect real costs. The concept of aggregating episodes of care to obtain a single value equating to cost to heal is likely to remain a challenging exercise for the foreseeable future. A better approach may be to provide a range of cost values that are dependent on specific methods, such as the ABC method.

Trends of the treatment of Critical Limb Ischemia during the last two decades

In this review 14 studies were identified reporting the treatment strategy in 4891 patients with Critical Limb Ischemia (CLI) with the aim to investigate if the strategy of treatment of the first episode of CLI has changed during the last 15-20 years. A computer research has been performed on PubMed and Scopus databases on November 2016. The used terms for the investigation about studies evaluating the strategy of treatment of CLI at the first-time presentation, have been "critical leg ischemia", "critical limb ischemia", "critical lower limb ischemia" along with the terms "placebo", "medical treatment" and/or "conservative" revascularisation, surgical revascularisation, endovascular revascularisation, hybrid revascularisation and primary amputation. Studies were included if they were either retrospective or prospective and reporting the rate of patients who underwent to any form of revascularization, conservative treatment and primary amputation. The one-year limb and life survival rates have been reported as major outcomes. The pooled rate of revascularization was 72.5% (95% CI 80-64.96) of which 54.5%, surgical, 38.3% endovascular and 7.1% hybrid. The bivariate regression of revascularisation procedures has been with not significant increase, from 68% in 1993 to 88% in 2015. The endovascular procedures have shown a significant increase of the trend, from 2% to more the 50% (p 0.007), while surgical and hybrid procedures have not. The pooled rate of conservative treatment was 18% (95% CI 11.6-24.5%) with a not significant increasing trend and primary amputation pooled rate was 8.7% (95% CI 12.0-5,4) with a significant decreasing trend (p 0.009). The one-year limb survival rate was 75,4% (95% CI 81.5-69.3%) and the life survival was 76%. (95% CI 85.4-66.1%) both with a not significant increasing trend. In conclusion, this review highlights how the treatment strategy of the first CLI manifestation has changed over the last 15-20 years. It has shown an increase of the rate of revascularization procedures, particularly for endovascular and a significant reduction of the rate of primary amputations. The rate of patients treated conservatively appears to be unchanged and maybe influencing the rate of limb and life survival, that have remained unchanged.

Cell Therapy for Chronic Limb-Threatening Ischemia: Current Evidence and Future Directions

Cell‐based therapies have gained interest as a potential treatment method in cardiovascular disease in the past two decades, peripheral artery disease amongst others. Initial pre‐clinical and small pilot clinical studies showed promising effects of cell therapy in peripheral artery disease and chronic limb‐threatening ischemia in particular. However, these promising results were not corroborated in larger high quality blinded randomized trials. This has led to a shift of the field towards more sophisticated cell products, especially mesenchymal stromal cells. Mesenchymal stromal cells have some important benefits, making these cells ideal for regenerative medicine, e.g., potential for allogeneic application, loss of disease‐mediated cell dysfunction, reduced production costs, off‐the‐shelf availability. Future high quality and large clinical studies have to prove the efficacy of mesenchymal stromal cells in the treatment of peripheral artery disease. Stem Cells Translational Medicine2018;7:842–846

Preventing Major Amputations in Patients with Critical Limb Ischemia

PURPOSE OF REVIEW

This review summarizes the risks of lower extremity amputation associated with critical limb ischemia (CLI) and discusses current therapies that can prevent amputation in CLI.

RECENT FINDINGS

CLI remains an under-recognized condition associated with high rates of major amputation and disparities in care. Optimal medical therapy can reduce the risk of major adverse cardiovascular and limb events, but revascularization combined with close wound care remains the cornerstone of amputation prevention. Endovascular revascularization has become more common over time and has been associated with a reduction in amputation rates. Ongoing clinical trials will help inform best practices for revascularization strategies and techniques. Vascular care is inconsistent across the USA, with significant variation in access to care revascularization rates and rates of major amputation. Major amputation can be prevented in patients with CLI when optimal medical therapy, lifestyle modification, and revascularization are provided in a multidisciplinary setting.

A Unique All-Payer Rate-Setting System Controls the Cost but Not the Racial Disparity in Lower Extremity Revascularization Procedures

BACKGROUND

Patients with peripheral arterial disease often have high comorbidity burden that may complicate post-interventional course and drive increased health-care expenditures. Racial disparity had been observed in lower extremity revascularization (LER) patterns and outcomes. In 2014, Maryland adopted an all-payer rate-setting system to limit the rising hospitalization costs. This resulted in an aggregate payment system in which hospital compensation takes place as an overall per capita expenditure for hospital services. We sought to examine racial differences and other patient-level factors that might lead to discrepancies in LER hospital costs in the State of Maryland.

METHODS

We used International Classification of Diseases, Ninth Revision codes to identify patients who underwent infrainguinal open bypass (open) and endovascular repair (endo) in the Maryland Health Services Cost Review Commission database (2009-2015). Multivariable generalized linear model regression analysis was conducted to report cost differences adjusting for patient-specific demographics, comorbidities, and insurance status. Logistic regression analysis was used to assess quality metrics: intensive care unit (ICU) admission, 30-day readmission, protracted length of stay (pLOS) (endo: pLOS >9, open: pLOS > 10 days) and in-hospital mortality.

RESULTS

Among patients undergoing open, costs were higher for nonwhite patients (African-American [AA]: $6,092 [4,682-7,501], other: $3,324 [437-6,212]; both P ≤ 0.024), diabetics ($2,058 [837-3,279]; P < 0.001), and patients with Medicaid had an increased cost over Medicare patients by $4,325 (1,441-7,209). Critical limb ischemia (CLI) was associated with $5,254 (4,014-6,495) risk-adjusted cost increment. In addition, AA patients demonstrated higher risk-adjusted odds of ICU admission (adjusted odds ratio [aOR] [95% confidence interval {CI}]:1.65 [1.46-1.86]; P < 0.001) and pLOS (aOR [95% CI]: 1.56 [1.37-1.79]; P < 0.001) than their white counterparts. For patients undergoing endo, costs were higher for nonwhite patients (AA: $2,642 [1,574-3,711], other: $4,124 [2,091-6,157]; both P < 0.001). Patients with CLI and heart failure had increased costs after endo. AA patients were more likely to be readmitted or stayed longer after endo (1.16 [1.03-1.29], 1.34 [1.21-1.49]; both P < 0.010, respectively). The overall cost trend was rapidly increasing before all-payer rate policy implementation but it dramatically plateaued after 2014.

CONCLUSIONS

This study showed that the all-payer rate-setting system has curbed the LER rising costs, but these costs remained disproportionally higher for disadvantaged populations such as AA and Medicaid communities. This underpins the existing racial disparity in LER. AA patients had higher LER costs, most likely driven by extended hospitalization and ICU admission. Efforts could be directed to evaluate the contributing socioeconomic factors, invest in primary prevention of comorbid conditions that had shown to be associated with prohibitive costs, and identify mechanisms to overcome the existing racial disparity in LER within the promising cost-saving payment system at the State of Maryland.

Risk of major amputation or death among patients with critical limb ischemia initially treated with endovascular intervention, surgical bypass, minor amputation, or conservative management

AIMS

Patients with critical limb ischemia (CLI) have an increased risk of major amputation. The initial treatment approach for CLI may significantly impact the subsequent risk of major amputation or death. The objective of this study was to describe the initial treatment approaches of patients with CLI and the limb outcomes associated with each approach.

METHODS

Data from MarketScan Commercial and Medicare Supplemental Databases from January 2006-December 2014 was utilized. Cohorts of CLI patients were defined as follows: (1) peripheral vascular intervention (PVI); (2) peripheral vascular surgery (PVS); (3) minor amputation without concomitant PVI or PVS (MinAMP); and (4) Patients without PVI, PVS, or MinAMP (conservative therapy). The odds of major amputation or inpatient death were estimated using the Cox proportional hazards model. For those patients requiring a major amputation, the incremental expenditures per member per month (PMPM) were estimated using a gamma log-link model.

RESULTS

Conservative therapy was associated with significantly higher odds of major amputation or inpatient death compared to patients who underwent minor amputation (1.59-times), PVI (2.08-times), or PVS (2.12-times). Patients treated with an initial strategy of minor amputation also had higher odds of major amputation or inpatient death compared to PVS (1.31-times) or PVI (1.33-times). The estimated incremental expenditures PMPM for patients with a major amputation was $5,165.

CONCLUSIONS

Revascularization reduces the risk of a major amputation or inpatient death for patients with CLI when compared to conservative therapy. Major amputation is also associated with significantly higher healthcare expenditures.

Hospital cost impact of orbital atherectomy with angioplasty for critical limb ischemia treatment: a modeling approach

AIM

The incremental cost of peripheral orbital atherectomy system (OAS) plus balloon angioplasty (BA) versus BA-only for critical limb ischemia was estimated.

MATERIALS & METHODS

A deterministic simulation model used clinical and healthcare utilization data from the CALCIUM 360° trial and current cost data. Incremental cost of OAS + BA versus BA-only included differential utilization during the procedure and adverse-event costs at 3, 6 and 12-months.

RESULTS

For every 100 procedures, incremental annual costs to the hospital were US$350,930 lower with OAS + BA compared with BA-only. Despite higher upfront costs, savings were realized due to reduced need for revascularization, amputation and end-of-life care over 6-12-month postoperative period.

CONCLUSION

Atherectomy with OAS prior to BA was associated with cost savings to the hospital.

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.

Treating Peripheral Artery Disease in the Wake of Rising Costs and Protracted Length of Stay

BACKGROUND

There has been growing scrutiny in the treatment of patients with peripheral artery disease due to the utilization of resources to manage this complex patient population. The purpose of this study was to determine the factors associated with prolonged length of stay (LOS > 7 days) following lower extremity bypass using data from the Vascular Quality Initiative as well as to define the additional costs incurred due to prolonged LOS in our health system.

METHODS

Summary statistics were performed of patients undergoing lower extremity bypass from 2010 to 2015. Student's t-tests and χ² tests were performed to compare those with and without prolonged LOS. Multivariable logistic regression was then performed to determine the independent predictors for increased LOS. We then compared our institutional LOS with that of representative institutions from the University Health System Consortium and evaluated the impact of prolonged LOS on limb salvage and survival.

RESULTS

This study included 334 patients with a mean age of 66.4 ± 12.4 years, 64.7% males, 58.5% of white race, 11.1% on dialysis, 80.5% smokers, and 53.6% with diabetes. The mean LOS was 15.7 ± 12.2 days. Prolonged LOS was associated with transfer (15.4% vs. 2.3%, P = 0.001), diabetes (58.3% vs. 40.2%, P = 0.004), critical limb ischemia (71.3% vs. 49.4%, P < 0.001), preoperative need for ambulatory assistance (44.5% vs. 16.1%, P < 0.001), prior ipsilateral bypass (6.9% vs. 1.1%, P = 0.042), urgent surgery (39.7% vs. 9.8%, P < 0.001), tibial or distal target vessel (52.7% vs. 28.0%, P < 0.001), use of vein (65.4% vs. 46.3%, P = 0.002), return to operating room (42.6% vs. 1.2%, P < 0.001), ambulatory assistance (65.0% vs. 34.1%, P < 0.001) as well as discharge anticoagulant (22.8% vs. 9.8%, P = 0.010). Multivariable logistic regression identified urgency (odds ratio [OR] = 5.09, 95% confidence interval [CI] 2.16-12.02, P < 0.001), critical limb ischemia (OR = 3.12, 95% CI 1.65-5.90, P < 0.001), return to OR (OR = 40.30, 95% CI 5.36-303.20, P < 0.001), use of vein (OR = 2.19, 95% CI 1.18-4.07, P = 0.013), and the need for anticoagulation at discharge (OR = 2.56, 95% CI 1.03-6.33, P = 0.043) as independent predictors of LOS > 7 days. Prolonged hospital stays accounted for an additional $40,561.64 in total cost and $26,028 in direct costs incurred. Despite these increased costs, limb salvage and overall survival were not adversely impacted in the prolonged LOS group in follow-up.

CONCLUSIONS

Lower extremity bypass is associated with a longer than expected LOS in our health system, much of which can be attributed to return to the OR for minor amputations and wound issues. This led to added total and direct costs, where the majority of this increase was attributable to prolonged LOS. Limb salvage and overall survival were preserved, however, in this subset of patients in follow-up. These findings suggest that lower extremity bypass patients are a resource-intensive population of patients, but that these costs are worthwhile in the setting of preserved limb salvage and overall survival.

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.

Ghrelin, MicroRNAs, and Critical Limb Ischemia: Hungering for a Novel Treatment Option

Critical limb ischemia (CLI) is the most severe manifestation of peripheral artery disease. It is characterized by chronic pain at rest, skin ulcerations, and gangrene tissue loss. CLI is a highly morbid condition, resulting in a severely diminished quality of life and a significant risk of mortality. The primary goal of therapy for CLI is to restore blood flow to the affected limb, which is only possible by surgery, but is inadvisable in up to 50% of patients. This subset of patients who are not candidates for revascularisation are referred to as "no-option" patients and are the focus of investigation for novel therapeutic strategies. Angiogenesis, arteriogenesis and vasculogenesis are the processes whereby new blood vessel networks form from the pre-existing vasculature and primordial cells, respectively. In therapeutic angiogenesis, exogenous stimulants are administered to promote angiogenesis and augment limb perfusion, offering a potential treatment option for "no option" patients. However, to date, very few clinical trials of therapeutic angiogenesis in patients with CLI have reported clinically significant results, and it remains a major challenge. Ghrelin, a 28-amino acid peptide, is emerging as a potential novel therapeutic for CLI. In pre-clinical models, exogenous ghrelin has been shown to induce therapeutic angiogenesis, promote muscle regeneration, and reduce oxidative stress via the modulation of microRNAs (miRs). miRs are endogenous, small, non-coding ribonucleic acids of ~20-22 nucleotides which regulate gene expression at the post-transcriptional level by either translational inhibition or by messenger ribonucleic acid cleavage. This review focuses on the mounting evidence for the use of ghrelin as a novel therapeutic for CLI, and highlights the miRs which orchestrate these physiological events.

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.