Association Between Diagnosis-to-Limb Revascularization Time and Clinical Outcomes in Outpatients With Chronic Limb-Threatening Ischemia: Insights From the CLIPPER Cohort.

BACKGROUND: The extent and consequences of ischemia in patients with chronic limb-threatening ischemia (CLTI) may change rapidly, and delays from diagnosis to revascularization may worsen outcomes. We sought to describe the association between time from diagnosis to endovascular lower extremity revascularization (diagnosis-to-limb revascularization [D2L] time) and clinical outcomes in outpatients with CLTI. METHODS AND RESULTS: In the CLIPPER cohort, comprising patients between 66 and 86 years old diagnosed with CLTI betweeen 2010 and 2019, we used Medicare claims data to identify patients who underwent outpatient endovascular revascularization within 180 days of diagnosis. We described the risk-adjusted association between D2L time and clinical outcomes. Among 1 130 065 patients aged between 66 and 86 years with CLTI, 99 221 (8.8%) underwent outpatient endovascular lower extremity revascularization within 180 days of their CLTI diagnosis. Among patients with D2L time <30 days, there was no association between D2L time and all-cause death or major lower extremity amputation. However, among patients with D2L time >30 days, each additional 10-day increase in D2L time was associated with a 2.5% greater risk of major amputation (hazard ratio, 1.025 [95% CI, 1.014-1.036]). There was no association between D2L time and all-cause death. CONCLUSIONS: A delay of >30 days from CLTI diagnosis to lower extremity endovascular revascularization was associated with an increased risk of major lower extremity amputation among patients undergoing outpatient endovascular revascularization. Improving systems of care to reduce D2L time could reduce amputations.

Inter-Rater Reliability for the Amputation Endpoint in the National Vascular Quality Initiative.

BACKGROUND: National quality reporting efforts after revascularization for peripheral artery disease (PAD) are ongoing. Validation of endpoints are necessary in national quality registries. OBJECTIVES: This study sought to examine the interrater reliability for the endpoint of major amputation at 1 year in the Vascular Quality Initiative (VQI) registry and the Medicare-linked Vascular Quality Initiative registry (VQI-VISION) against electronic health record (EHR) review. METHODS: Surgical or endovascular revascularization procedures between January 1, 2010, and December 31, 2017, in the VQI registry and VQI-VISION for 2 academic health systems were queried. Major amputation data were abstracted by trained data collectors for the VQI and derived from Current Procedural Terminology codes for VQI-VISION. Cases underwent protocolized adjudication for the endpoint of major amputation by EHR review. Paired tests were used to evaluate the sensitivity and specificity. Spearman's ρ and Cohen's κ were used to evaluate interrater reliability. RESULTS: Amputation endpoints for 1,936 revascularizations were examined. Compared with major amputation data in EHR review, the sensitivity for the VQI registry was 35.9% and the specificity was 99.4% (ρ = 0.53; κ = 0.48). For VQI-VISION, sensitivity was 67.7% and specificity was 98.9% (ρ = 0.75; κ = 0.74). For any amputation in VQI data, sensitivity was 35.3% and specificity was 99.3% (ρ = 0.53; κ = 0.46), and for VQI-VISION, they were 71.6% and 97.7%, respectively (ρ = 0.75; κ = 0.74). CONCLUSIONS: Almost two-thirds of the amputations in the VQI registry and one-third of amputations in VQI-VISION were missing at 1 year compared against adjudicated EHR review. In preparing for national reporting systems for major amputation tracking, data collection system reform is needed.

Evaluation of short-term mortality in patients with Medicare undergoing endovascular interventions for chronic limb-threatening ischemia.

INTRODUCTION: Patients with chronic limb-threatening ischemia (CLTI) have high mortality rates after revascularization. Risk stratification for short-term outcomes is challenging. We aimed to develop machine-learning models to rank predictive variables for 30-day and 90-day all-cause mortality after peripheral vascular intervention (PVI). METHODS: Patients undergoing PVI for CLTI in the Medicare-linked Vascular Quality Initiative were included. Sixty-six preprocedural variables were included. Random survival forest (RSF) models were constructed for 30-day and 90-day all-cause mortality in the training sample and evaluated in the testing sample. Predictive variables were ranked based on the frequency that they caused branch splitting nearest the root node by importance-weighted relative importance plots. Model performance was assessed by the Brier score, continuous ranked probability score, out-of-bag error rate, and Harrell's C-index. RESULTS: A total of 10,114 patients were included. The crude mortality rate was 4.4% at 30 days and 10.6% at 90 days. RSF models commonly identified stage 5 chronic kidney disease (CKD), dementia, congestive heart failure (CHF), age, urgent procedures, and need for assisted care as the most predictive variables. For both models, eight of the top 10 variables were either medical comorbidities or functional status variables. Models showed good discrimination (C-statistic 0.72 and 0.73) and calibration (Brier score 0.03 and 0.10). CONCLUSION: RSF models for 30-day and 90-day all-cause mortality commonly identified CKD, dementia, CHF, need for assisted care at home, urgent procedures, and age as the most predictive variables as critical factors in CLTI. Results may help guide individualized risk-benefit treatment conversations regarding PVI.

Investigating the impact of suboptimal prescription of preoperative antiplatelets and statins on race and ethnicity-related disparities in major limb amputation.

BACKGROUND: Non-Hispanic Black and Hispanic patients with symptomatic PAD may receive different treatments than White patients with symptomatic PAD. The delivery of guideline-directed medical treatment may be a modifiable upstream driver of race and ethnicity-related disparities in outcomes such as limb amputation. The purpose of our study was to investigate the prescription of preoperative antiplatelets and statins in producing disparities in the risk of amputation following revascularization for symptomatic peripheral artery disease (PAD). METHODS: We used data from the Vascular Quality Initiative, a vascular procedure-based registry in the United States (2011-2018). We estimated the probability of preoperative antiplatelet and statin prescriptions and 1-year incidence of amputation. We then estimated the amputation risk difference between race/ethnicity groups that could be eliminated under a hypothetical intervention. RESULTS: Across 100,579 revascularizations, the 1-year amputation risk was 2.5% (2.4%, 2.6%) in White patients, 5.3% (4.9%, 5.6%) in Black patients, and 5.3% (4.7%, 5.9%) in Hispanic patients. Black (57.5%) and Hispanic patients (58.7%) were only slightly less likely than White patients (60.9%) to receive antiplatelet and statin therapy. However, the effect of antiplatelets and statins was greater in Black and Hispanic patients such that, had all patients received these medications, the estimated risk difference comparing Black to White patients would have reduced by 8.9% (-2.9%, 21.9%) and the risk difference comparing Hispanic to White patients would have been reduced by 17.6% (-0.7%, 38.6%). CONCLUSION: Even though guideline-directed care appeared evenly distributed by race/ethnicity, increasing access to such care may decrease health care disparities in major limb amputation.

Implementing methods in the ELEGANCE registry to increase diversity in clinical research.

OBJECTIVE: Women and underrepresented minorities (URMs) who are at an increased risk of presenting with severe peripheral artery disease (PAD) and have different responses to treatment compared with non-Hispanic White males yet are underrepresented in PAD research. METHODS: ELEGANCE is a global, prospective, multi-center, post-market registry of PAD patients treated with drug-eluting device that aims to enroll at least 40% women and 40% URMs. The study design incorporates strategies to increase enrollment of women and URMs. Inclusion criteria are age ≥18 years and treatment with any commercially available Boston Scientific Corporation drug-eluting device marketed for peripheral vasculature lesions; exclusion criterion is life expectancy <1 year. RESULTS: Of 750 patients currently enrolled (951 lesions) across 39 sites, 324 (43.2%) are female and 350 (47.3%) are URMs (21.6% Black, 11.2% Asian, 8.5% Hispanic/Latino, and 5.3% other). Rutherford classification is distributed differently between sexes (P = .019). Treatment indication differs among race/ethnicity groups (P = .003). Chronic limb-threatening ischemia was higher for Black (38.3%) and Hispanic/Latino (28.1%) patients compared with non-Hispanic White (21.8%) and Asian patients (21.4%). De-novo stenosis was higher in Asian patients (92.3%) compared with Black, non-Hispanic White, and Hispanic/Latino patients (72.2%, 68.7%, and 77.8%, respectively; P < .001). Mean lesion length was longest for Black patients (162.7 mm), then non-Hispanic White (135.2 mm), Asian (134.8 mm), and Hispanic/Latino patients (128.1 mm; P = .008). CONCLUSIONS: Analyses of data from the ELEGANCE registry show that differences exist in baseline disease characteristics by sex and race/ethnicity; these may be the result of other underlying factors, including time to diagnosis, burden of undermanaged comorbidities, and access to care.

A systematic review and meta-analysis on the influence of sociodemographic factors on amputation in patients with peripheral arterial disease.

OBJECTIVE: To identify disparities in sociodemographic factors that are associated with major lower limb amputation in patients with peripheral arterial disease (PAD). METHODS: A systematic review of the literature was performed to identify studies that reported major lower limb amputation rates in patients with PAD among different sociodemographic groups. Data that compared amputation rates on the basis of sex, race, ethnicity, income, insurance, geography, and hospital type were collected and described. Outcomes were then aggregated and standardized, and a meta-analysis was performed to synthesis data into single odds ratios (ORs). RESULTS: Forty-one studies were included in the review. There was no association found between males and females (OR, 0.95; 95% confidence interval [CI], 0.90-1.00). Compared with Whites, higher rates of amputation were seen among Blacks/African Americans (OR, 2.02; 95% CI, 1.81-2.26) and Native Americans (OR, 1.22; 95% CI, 1.04-1.45). No significant association was found between Whites and Asians, Native Hawaiians, or Pacific Islanders (OR, 1.15; 95% CI, 1.00-1.33). Hispanics had higher rates of amputation compared with non-Hispanics (OR, 1.36; 95% CI, 1.22-1.52). Compared with private insurance, higher rates of amputation were seen among Medicare patients (OR, 1.38; 95% CI, 1.27-1.50), Medicaid patients (OR, 1.59; 95% CI, 1.44-1.76), and noninsured patients (OR, 1.41; 95% CI, 1.02-1.95). Compared with the richest income quartile, higher rates of amputation were seen among the second income quartile (OR, 1.10; 95% CI, 1.05-1.15), third income quartile (OR, 1.20; 95% CI, 1.07-1.35), and bottom income quartile (OR, 1.36; 95% CI, 1.24-1.49). There was no association found between rural and urban populations (OR, 1.35; 95% CI, 0.92-1.97) or between teaching and nonteaching hospitals (OR, 1.01; 95% CI, 0.91-1.12). CONCLUSIONS: Our study has identified a number of disparities and quantified the influence of sociodemographic factors on major lower limb amputation rates owing to PAD between groups. We believe these findings can be used to better target interventions aimed at decreasing amputation rates, although further research is needed to better understand the mechanisms behind our findings.

Role of Hemodynamic Assessment and Limitations in Ankle-Brachial Pressure Index, Toe- Brachial Pressure Index to Predict Wound Healing After Revascularization.

Chronic limb-threatening ischemia (CLTI) represents one of the most severe forms of peripheral arterial disease implying impaired wound healing and tissue loss at the same time posing a significant impact on the quality of life of patients and a serious economic burden on healthcare systems around the world. A major challenge in the management of patients with CLTI is the validity and role of non-invasive hemodynamic parameters in assessing their clinical status before and after revascularization. Traditionally, the diagnosis of CLTI is routinely based on clinical symptoms and confirmed by measurements of non-invasive limb hemodynamics including ankle-brachial pressure index (ABPI) and toe-brachial pressure index (TBPI). However, whether these indices alone can provide definitive treatment or be used as adjunctive tool along with the implementation of novel techniques to help guide revascularization for CLI patients still remains unclear.

Impact of Intensity of Vascular Care Preceding Major Amputation Among Patients With Chronic Limb-Threatening Ischemia.

BACKGROUND: Lower-limb amputation rates in patients with chronic limb-threatening ischemia vary across the United States, with marked disparities in amputation rates by gender, race, and income status. We evaluated the association of patient, hospital, and geographic characteristics with the intensity of vascular care received the year before a major lower-limb amputation and how intensity of care associates with outcomes after amputation. METHODS: Using Medicare claims data (2016-2019), beneficiaries diagnosed with chronic limb-threatening ischemia who underwent a major lower-limb amputation were identified. We examined patient, hospital, and geographic characteristics associated with the intensity of vascular care received the year before amputation. Secondary objectives evaluated all-cause mortality and adverse events following amputation. RESULTS: Of 33 036 total Medicare beneficiaries undergoing major amputation, 7885 (23.9%) were due to chronic limb-threatening ischemia; of these, 4988 (63.3%) received low-intensity and 2897 (36.7%) received high-intensity vascular care. Mean age, 76.6 years; women, 38.9%; Black adults, 24.5%; and of low income, 35.2%. After multivariable adjustment, those of low income (odds ratio, 0.65 [95% CI, 0.58-0.72]; P<0.001), and to a lesser extent, men (odds ratio, 0.89 [95% CI, 0.81-0.98]; P=0.019), and those who received care at a safety-net hospital (odds ratio, 0.87 [95% CI, 0.78-0.97]; P=0.012) were most likely to receive low intensity of care before amputation. High-intensity care was associated with a lower risk of all-cause mortality 2 years following amputation (hazard ratio, 0.79 [95% CI, 0.74-0.85]; P<0.001). CONCLUSIONS: Patients who were of low-income status, and to a lesser extent, men, or those cared for at safety-net hospitals were most likely to receive low-intensity vascular care. Low-intensity care was associated with worse long-term event-free survival. These data emphasize the continued disparities that exist in contemporary vascular practice.

Racial Disparities in Treatment Indications and Outcomes for Limb Ischemia.

BACKGROUND: Studies suggest that the Affordable Care Act (ACA) of 2014 has improved access to vascular care and vascular outcomes among patients suffering from peripheral arterial disease (PAD). We sought to examine the racial disparities that exist in patients with PAD who have undergone lower extremity bypass (LEB) or a peripheral vascular intervention (PVI) using the Vascular Quality initiative (VQI) database. METHODS: The VQI infrainguinal and PVI datasets were queried for patients receiving elective and urgent LEB or PVI between 2016, 2 years after ACA implementation, and in 2021. Patients undergoing interventions urgently/emergently or for aneurysm were excluded. The primary outcome was major adverse limb event (MALE-defined as any vascular reintervention or above-ankle amputation) free survival at 1 year. Standard statistical methods were utilized as appropriate. RESULTS: A total of 17,455 LEB and 87,475 PVIs were included in this analysis. Black persons present at a younger age when compared to non-Hispanic White persons (NHW) and are more likely to have diabetes, hypertension, end-stage renal disease (ESRD), and higher rates of prior amputation. Black persons are more likely to present with chronic limb-threatening ischemia (CLTI) rather than claudication, and in a more urgent setting. Postoperative outcomes show higher rates of major amputations among racial minorities, specifically Black persons for both LEB (1.8% vs. 0.8% P < 0.001) and PVI (20.8% vs. 16.8% P < 0.001). Black persons are at higher risk of 1-year MALE for LEB (36.7% vs. 29.9% P < 0.001) and PVI (31.0% vs. 21.7%; P < 0.001). Even after adjusting for confounding variables, Black persons have a higher risk of 1-year MALE for LEB, with an adjusted hazard ratio (aHR) of 1.15 (95% CI [1.05-1.26], P = 0.003) and PVI (aHR 1.18 95% CI [1.12-1.24], P < 0.001). Other major determinates of 1-year MALE on multivariate Cox regression included CLTI (LEB aHR 1.57 95% CI [1.43-1.72], P < 0.001; PVI aHR 2.29 95% CI [2.20-2.39], P < 0.001) and history of prior amputation (LEB aHR 1.35 95% CI [1.17-1.56], P < 0.001; PVI aHR 1.5 95% CI [1.4-1.6], P < 0.001). CONCLUSIONS: Compared to NHW persons, Black persons present with more advanced vascular disease regardless of the operative indication. Black persons are also at significantly higher risk of 1-year MALE. Despite some advances in more accessible care through the ACA of 2014, our observations suggest that Black persons still have significantly worse outcomes due to variety of variables that need further investigation.

Association between readmission care fragmentation and outcomes after interventions for peripheral arterial disease.

OBJECTIVE: Lower extremity revascularization (LER) for peripheral artery disease is complicated by the frequent need for readmission. However, it is unclear if readmission to a nonindex LER facility (ie, a facility different from the one where the LER was performed) compared with the index LER facility is associated with worse outcomes. METHODS: This was a national cohort study of older adults who underwent open, endovascular, or hybrid LER for peripheral artery disease (January 1, 2010, to December 31, 2018) in the Vascular Quality Initiative who were readmitted within 90 days of their vascular procedure. This dataset was linked to Medicare claims and the American Hospital Association Annual Survey. The primary outcome was 90-day mortality and the secondary outcome was major amputation at 90 days after LER. The primary exposure was the location of the first readmission after LER (categorized as occurring at the index LER facility vs a nonindex LER facility). Generalized estimating equations logistic regression models were used to assess the association between readmission location and 90-day mortality and amputation. RESULTS: Among 42,429 patients who underwent LER, 33.0% were readmitted within 90 days. Of those who were readmitted, 27.3% were readmitted to a nonindex LER facility, and 42.2% of all readmissions were associated with procedure-related complications. Compared with patients readmitted to the index LER facility, those readmitted to a nonindex facility had a lower proportion of procedure-related reasons for readmission (21.5% vs 50.1%; P < .001). Most of the patients readmitted to a nonindex LER facility lived further than 31 miles from the index LER facility (39.2% vs 19.6%; P < .001) and were readmitted to a facility with a total bed size of <250 (60.1% vs 11.9%; P < .001). Readmission to a nonindex LER facility was not associated with 90-day mortality or 90-day amputation. However, readmission for a procedure-related complication was associated with major amputation (90-day amputation: adjusted odds ratio, 3.33; 95% confidence interval, 2.89-3.82). CONCLUSIONS: Readmission after LER for a procedure-related complication is associated with subsequent amputation. This finding suggests that quality improvement efforts should focus on understanding various types of procedure-related failure after LER and its role in limb salvage.

Area Deprivation Index is not predictive of worse outcomes after open lower extremity revascularization.

OBJECTIVE: Prior research has shown that socioeconomic status (SES) is associated with higher rates of diabetes, peripheral vascular disease, and amputation. We sought to determine whether SES or insurance type increases the risk of mortality, major adverse limb events (MALE), or hospital length of stay (LOS) after open lower extremity revascularization. METHODS: We conducted a retrospective analysis of patients who underwent open lower extremity revascularization at a single tertiary care center from January 2011 to March 2017 (n = 542). SES was determined using state Area Deprivation Index (ADI), a validated metric determined by income, education, employment, and housing quality by census block group. Patients undergoing amputation in this same time period (n = 243) were included to compare rates of revascularization to amputation by ADI and insurance status. For patients undergoing revascularization or amputation procedures on both limbs, each limb was treated individually for this analysis. We performed a multivariate analysis of the association between ADI and insurance type with mortality, MALE, and LOS using Cox proportional hazard models, including confounding variables such as age, gender, smoking status, body mass index, hyperlipidemia, hypertension, and diabetes. The cohort with an ADI quintile of 1, meaning least deprived, and the Medicare cohort were used for reference. P values of <.05 were considered statistically significant. RESULTS: We included 246 patients undergoing open lower extremity revascularization and 168 patients undergoing amputation. Controlling for age, gender, smoking status, body mass index, hyperlipidemia, hypertension, and diabetes, ADI was not an independent predictor of mortality (P = .838), MALE (P = .094), or hospital LOS (P = .912). Controlling for the same confounders, uninsured status was independently predictive of mortality (P = .033), but not MALE (P = .088) or hospital LOS (P = .125). There was no difference in the distribution of revascularizations or amputations by ADI (P = .628), but there was higher proportion of uninsured patients undergoing amputation compared with revascularization (P < .001). CONCLUSIONS: This study suggests that ADI is not associated with an increased risk of mortality or MALE in patients undergoing open lower extremity revascularization, but that uninsured patients are at higher risk of mortality after revascularization. These findings indicate that individuals undergoing open lower extremity revascularization at this single tertiary care teaching hospital received similar care, regardless of their ADI. Further study is warranted to understand the specific barriers that uninsured patients face.

Trends of Concomitant Diabetes and Peripheral Artery Disease and Lower Extremity Amputation in US Medicare Patients, 2007 to 2019.

BACKGROUND: Previous studies demonstrate geographic and racial/ethnic variation in diagnosis and complications of diabetes and peripheral artery disease (PAD). However, recent trends for patients diagnosed with both PAD and diabetes are lacking. We assessed the period prevalence of concurrent diabetes and PAD across the United States from 2007 to 2019 and regional and racial/ethnic variation in amputations among Medicare patients. METHODS: Using Medicare claims from 2007 to 2019, we identified patients with both diabetes and PAD. We calculated period prevalence of concomitant diabetes and PAD and incident cases of diabetes and PAD for every year. Patients were followed to identify amputations, and results were stratified by race/ethnicity and hospital referral region. RESULTS: 9 410 785 patients with diabetes and PAD were identified (mean age, 72.8 [SD, 10.94] years; 58.6% women, 74.7% White, 13.2% Black, 7.3% Hispanic, 2.8% Asian/API, and 0.6% Native American). Period prevalence of diabetes and PAD was 23 per 1000 beneficiaries. We observed a 33% relative decrease in annual new diagnoses throughout the study. All racial/ethnic groups experienced a similar decline in new diagnoses. Black and Hispanic patients had on average a 50% greater rate of disease compared with White patients. One- and 5-year amputation rates remained stable at ≈1.5% and 3%, respectively. Native American, Black, and Hispanic patients were at greater risk of amputation compared with White patients at 1- and 5-year time points (5-year rate ratio range, 1.22-3.17). Across US regions, we observed differential amputation rates, with an inverse relationship between the prevalence of concomitant diabetes and PAD and overall amputation rates. CONCLUSIONS: Significant regional and racial/ethnic variation exists in the incidence of concomitant diabetes and PAD among Medicare patients. Black patients in areas with the lowest rates of PAD and diabetes are at disproportionally higher risk for amputation. Furthermore, areas with higher prevalence of PAD and diabetes have the lowest rates of amputation.

ZILVERPASS Study: ZILVER PTX Stent vs. Bypass Surgery in Femoropopliteal Lesions, 3 year results and economic analysis.

BACKGROUND: To report the 3-year safety and effectiveness results of a multicenter, prospective, randomized controlled trial comparing the ZILVER PTX paclitaxel-eluting stent to surgical bypass and to conduct a health economic analysis up to 3-year follow-up of the two treatment modalities. METHODS: This is a study in symptomatic TransAtlantic Inter-Society Consensus (TASC) C and D femoropopliteal lesions comparing endovascular ZILVER PTX stenting vs. surgical bypass surgery using a prosthetic graft (ClinicalTrials.gov identifier NCT01952457). Between October 2013 and July 2017, 220 patients (mean age 68.6±10.5 years; 159 men) were enrolled and randomized to the ZILVER PTX treatment group (113, 51.40%) or the bypass treatment group (107, 48.60%). One of the secondary outcomes was primary patency at 3-year, defined as no evidence of binary restenosis or occlusion within the target lesion or bypass graft based on a duplex ultrasound peak systolic velocity ratio <2.4 and no clinically-driven target lesion revascularization (TLR) in endovascular cases or reintervention to restore flow in the bypass. An economic analysis was conducted to analyze the cost differences between ZILVER PTX and bypass, which shows the perspective of the public authority/organization that pays for healthcare in the two countries (payor), Germany and USA. RESULTS: The 3-year primary patency rate was 53.30% (95% CI 61.40% to 45.20%) for the ZILVER PTX group vs. 58.20% (95% CI 67.10% to 49.30%) for the bypass arm (P=0.9721). Freedom from TLR at 3-year was 62.80% (95% CI 72.60% to 53%) for the ZILVER PTX group vs. 65.30% (95% CI 75.40% to 55.20%) for the bypass group (P=0.635). There was also no significant difference (P=0.358) in survival rate at 3-year between the ZILVER PTX group 78.50%, (95% CI to 87.70% to 69.30%) and the bypass group 87.40% (95% CI 97.6% to 77.2%). None of the deaths was categorized as related to the procedure or device. The economic analysis, taking into account procedural-, hospitalization- and reintervention costs, showed a clear cost-benefit for Zilver PTX in both investigated countries up to 3-year follow-up: Germany (Bypass €9446 per patient versus ZILVER PTX €5755) and USA (Bypass $26,373 per patient versus ZILVER PTX $19,186). CONCLUSIONS: The non-inferior safety and effectiveness results of the ZILVER PTX stent were associated with lower costs for the payer and confirmed that ZILVER PTX stent treatment can be considered as a valid alternative for bypass surgery in long and complex femoropopliteal lesions.

Association of Health Care Utilization and Access to Care With Vascular Assessment Before Major Lower Extremity Amputation Among US Veterans.

Importance: Patient-level characteristics alone do not account for variation in care among US veterans with peripheral artery disease (PAD). Presently, the extent to which health care utilization and regional practice variation are associated with veterans receiving vascular assessment prior to major lower extremity amputation (LEA) is unknown. Objective: To assess whether demographics, comorbidities, distance to primary care, the number of ambulatory clinic visits (primary and medical specialty care), and geographic region are associated with receipt of vascular assessment prior to LEA. Design, Setting, and Participants: This national cohort study used US Department of Veterans Affairs' Corporate Data Warehouse data from March 1, 2010, to February 28, 2020, for veterans aged 18 or older who underwent major LEA and who received care at Veterans Affairs facilities. Exposures: The number of ambulatory clinic visits (primary and medical specialty care) in the year prior to LEA, geographic region of residence, and distance to primary care. Main Outcomes and Measures: The main outcome was receipt of a vascular assessment (vascular imaging study or revascularization procedure) in the year prior to LEA. Results: Among 19 396 veterans, the mean (SD) age was 66.78 (10.20) years and 98.5% were male. In the year prior to LEA, 8.0% had no primary care visits and 30.1% did not have a vascular assessment. Compared with veterans with 4 to 11 primary care clinic visits, those with fewer visits were less likely to receive vascular assessment in the year prior to LEA (1-3 visits: adjusted odds ratio [aOR], 0.90; 95% CI, 0.82-0.99). Compared with veterans who lived less than 13 miles from the closest primary care facility, those who lived 13 miles or more from the facility were less likely to receive vascular assessment (aOR, 0.88; 95% CI, 0.80-0.95). Veterans who resided in the Midwest were most likely to undergo vascular assessment in the year prior to LEA than were those living in other regions. Conclusions and Relevance: In this cohort study, health care utilization, distance to primary care, and geographic region were associated with intensity of PAD treatment before LEA, suggesting that some veterans may be at greater risk of suboptimal PAD care practices. Development of clinical programs, such as remote patient monitoring and management, may represent potential opportunities to improve limb preservation rates and the overall quality of vascular care for veterans.

Interruption of Insurance Coverage and the Risk of Amputation in Patients with Pre-Existing Commercial Health Insurance and Peripheral Artery Disease.

BACKGROUND: Peripheral artery disease (PAD) is linked with an increased risk of lower extremity amputation and multiple socioeconomic factors attenuate this risk. Prior studies have demonstrated increased rates of amputation in PAD patients with suboptimal or no insurance coverage. However, the impact of insurance loss in PAD patients with pre-existing commercial insurance coverage is unclear. In this study, we evaluated the outcomes of PAD patients who lose commercial insurance coverage. METHODS: The Pearl Diver all-payor insurance claims database was used to identify adult patients (>18 years) with a PAD diagnosis from 2010 to 2019. The study cohort included patients with pre-existing commercial insurance and at least 3 years continuous enrollment after diagnosis of PAD. Patients were stratified based on whether they had an interruption of commercial insurance coverage over time. Patients who transitioned from commercial insurance to Medicare and other government-sponsored insurance during follow up were excluded. Adjusted comparison (1:1 ratio) was performed using propensity matching for age, gender, the Charlson Comorbidity Index (CCI), and relevant comorbidities. The main outcomes were major amputation and minor amputation. Cox proportional hazards ratios and Kaplan-Meier estimate were used to examine the association between loss of insurance and outcomes. RESULTS: Among the 214,386 patients included, 43.3% (n = 92,772) had continuous commercial insurance coverage and 56.7% (n = 121,614) had interruption of coverage (transition to uninsured or Medicaid coverage) during follow up. In the crude cohort and matched cohort, interruption of coverage was associated with lower major amputation-free survival on Kaplan Meier estimate (P < 0.001). In the crude cohort, interruption of coverage was associated with 77% increased risk of major amputation (OR 1.77, 95% CI 1.49-2.12) and a 41% high risk of minor amputation (OR 1.41, 95% CI 1.31-1.53). In the matched cohort, interruption of coverage was associated with 87% increased risk of major amputation (OR 1.87, 95% CI 1.57-2.25) and a 104% increased risk of minor amputation (OR 1.47, 95% CI 1.36-1.60). CONCLUSIONS: Interruption of insurance coverage in PAD patients with pre-existing commercial health insurance was associated with increased risks of lower extremity amputation.

Technical success and associated economic implications of conventional re-entry devices in subintimal recanalization of femoro-popliteal chronic total occlusions.

PURPOSE: Re-entry devices contribute to the high success rate of subintimal recanalization of chronic total occlusions (CTO). However, to date, there are no studies comparing the available conventional re-entry devices concerning the impact of their technical success on economic aspects, as these devices differ greatly in their acquisition costs. This prospective observational study intends to contribute to this question. METHODS: Prior to the start of the prospective study, all previous applications of the Outback® in femoro-popliteal CTO since its introduction to our hospital were analyzed retrospectively (n = 31). From June 2018 until January 2020, all patients with femoro-popliteal CTO treated with clear subintimal recanalization were included (n = 109). In the case of failed spontaneous re-entry, either the OffRoad® (study arm I, n = 20) or the Enteer® catheter (study arm II, n = 20) was used. If assisted re-entry failed, the Outback® device was used as a bailout. Baseline demographic and clinical data, morphologic characteristics, and technical success were documented. Additional per-patient costs due to the use of re-entry devices were analyzed. RESULTS: A retrospective evaluation of all Outback® applications revealed a technical success rate of 97% (30/31). In the prospective study, 63% (68/109) were successfully treated without using re-entry devices. The overall procedural success was 95% (103/109). In study arm I, the OffRoad® achieved a success rate of 45% (9/20), with a subsequent successful application of the Outback® in 80% (8/10) of the failed cases. In study arm II, the Enteer® was successfully employed in 60% (12/20) of cases, and the Outback® was then used successfully in a further 62% (5/8) of cases. Too large a distance between the device and the target lumen was a knockout criterion for all tested devices, leading to a subgroup analysis with the exclusion of three cases, resulting in a success rate of 47% for the OffRoad® and 67% for the Enteer® device. Furthermore, in severe calcification, only the Outback® reliably enabled revascularization. Significant savings of almost €600 were only achieved in study arm II according to German prices. CONCLUSION: With proper patient selection, a gradual approach with the Enteer® as the primarily used device, with the Outback® used additionally in case of failure, leads to significant savings and can be recommended. In severe calcification, the Outback® should be used as the primary device.

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.

Increased Medicaid eligibility of Affordable Care Act: Evidence of improved outcomes for patients with peripheral artery disease.

Peripheral artery disease (PAD) is a debilitating disease that disproportionately affects people of low socioeconomic status and racial minority individuals. These groups also tend to have lower rates of revascularization and worse outcomes, including higher rates of major amputation. In 2010, the Affordable Care Act (ACA) was signed into law, providing better opportunities for health care access to millions of uninsured Americans, although the implementation of different components started at a later date. Political issues led to uneven adaptation by states of the different ACA components. In states that adopted Medicaid expansion under the ACA, similar to that under the Massachusetts Health Care Reform Law of 2006, patients of low socioeconomic status and racial minority patients gained better access to health care. This review article will examine the disparities that exist in peripheral artery disease outcomes, as well as the effects of the ACA and Medicaid expansion on revascularization, limb salvage, and major amputation rates.

Community distress and risk of adverse outcomes after peripheral vascular intervention.

INTRODUCTION: Community distress is associated with adverse outcomes in patients with cardiovascular disease; however, its impact on clinical outcomes after peripheral vascular intervention (PVI) is uncertain. The Distressed Communities Index (DCI) is a composite measure of community distress measured at the zip code level. We evaluated the association between community distress, as measured by the DCI, and 24-month mortality and major amputation after PVI. METHODS: We used the Vascular Quality Initiative database, linked with Medicare claims data, to identify patients who underwent initial femoropopliteal PVI between 2017 and 2018. DCI scores were assigned using patient-level zip code data. The primary outcomes were 24-month mortality and major amputation. We used time-dependent receiver operating characteristic curve analysis to determine an optimal DCI value to stratify patients into risk categories for 24-month mortality and major amputation. Mixed Cox regression models were constructed to estimate the association of DCI with 24-month mortality and major amputation. RESULTS: The final cohort consisted of 16,864 patients, of whom 4734 (28.1%) were classified as having high community distress (DCI ≥70). At 24 months, mortality was elevated in patients with high community distress (30.7% vs 29.5%, P = .02), as was major amputation (17.2% vs 13.1%, P <.001). After adjusting for demographic and clinical characteristics, a 10-point higher DCI score was associated with increased risk of mortality (hazard ratio: 1.01; 95% confidence interval: 1.00-1.03) and major amputation (hazard ratio: 1.02; 95% confidence interval: 1.00-1.04). CONCLUSIONS: High community distress is associated with increased risk of mortality and major amputation after PVI.