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.

Variability in guideline-directed medical therapy across sites and operators and long-term mortality and amputation outcomes risk in patients undergoing peripheral vascular interventions.

BACKGROUND: The use of guideline-directed medical therapy (GDMT) in patients undergoing peripheral vascular interventions (PVIs) decreases the risk of death and amputation and may decrease hospital readmissions. The variability of GDMT prescription across sites and operators and the proportionality of risk is not well understood. We aimed to study the association between variability of GDMT prescription at the site and operator level and outcomes (including 90-day readmissions and 24-month all-cause mortality and major amputation). METHODS: We examined GDMT discharge rates in PVIs performed between 2017 and 2018 using Medicare-linked Vascular Quality Initiative registry. GDMT included a statin, antiplatelet therapy, and angiotensin-converting enzyme inhibitor/angiotensin receptor blocker (ACE-i/ARB) if hypertensive. Quartiles (Q1-4) of GDMT rates were documented by operators and sites and variability was quantified using median odds ratios (MOR) and intraclass correlation (ICC). The association between lower GDMT rates (per 10%) by sites and operators with 90-day readmission were calculated using logistic regression, and with 24-month mortality and major amputation using parametric survival model. Models were adjusted for patient-level factors and included sites and operators nested within sites as 2 random effects. RESULTS: GDMT rates for 17,147 patients across 223 sites and 1,263 operators ranged from 0% to 38% (Q1, MOR 1.43, 95%CI 1.39-1.47, P ≤ .001) to 57%-100% (Q4, MOR 1.48, 95%CI 1.44-1.51, P ≤ .001). Four percent of variance in GDMT use was explained by sites (ICC 3.9, 95%CI 2.9-5.3) and operators (ICC 4.1, 95%CI 3.1-5.4). A dose-response relationship was noted between lower GDMT rates and increased risk of 90-day readmission risk by sites (P = .021) and operators (P < .001). Lower GDMT prescription by site was associated with higher risk of 24-month mortality (HR = 1.07, 95%CI 1.02-1.13) and major amputation (HR = 1.08, 95%CI 1.01-1.15). Similar associations were found for GDMT use by provider (mortality HR = 1.05, 95%CI 1.02-1.08 and amputation HR = 1.04, 95%CI 1.00-1.08). CONCLUSION: Both at the operator and health system level, there was significant variability in GDMT prescription following PVI, proportionally translating into risk for readmission, mortality, and major amputation. Targeted quality efforts should prioritize both operator and site levels to improve GDMT use and outcomes for patients undergoing PVI.

Psychosocial and socioeconomic factors are most predictive of health status in patients with claudication.

BACKGROUND: As a key treatment goal for patients with symptomatic peripheral artery disease (PAD), improving health status has also become an important end point for clinical trials and performance-based care. An understanding of patient factors associated with 1-year PAD health status is lacking in patients with PAD. METHODS: The health status of 1073 consecutive patients with symptomatic PAD in the international multicenter PORTRAIT (Patient-Centered Outcomes Related to Treatment Practices in Peripheral Arterial Disease: Investigating Trajectories) registry was measured at baseline and 1 year with the Peripheral Artery Questionnaire (PAQ). The association of 47 patient characteristics with 1-year PAQ scores was assessed using a random forest algorithm. Variables of clinical significance were retained and included in a hierarchical multivariable linear regression model predicting 1-year PAQ summary scores. RESULTS: The mean age of patients was 67.7 ± 9.3 years, and 37% were female. Variables with the highest importance ranking in predicting 1-year PAQ summary score were baseline PAQ summary score, Patient Health Questionnaire-8 depression score, Generalized Anxiety Disorder-2 anxiety score, new onset symptom presentation, insurance status, current or prior diagnosis of depression, low social support, initial invasive treatment, duration of symptoms, and race. The addition of 19 clinical variables in an extended model marginally improved the explained variance in 1-year health status (from R2 0.312 to 0.335). CONCLUSIONS: Patients' 1-year PAD-specific health status, as measured by the PAQ, can be predicted from 10 mostly psychosocial and socioeconomic patient characteristics including depression, anxiety, insurance status, social support, and symptoms. These characteristics should be validated and tested in other PAD cohorts so that this model can inform risk adjustment and prediction of PAD health status in comparative effectiveness research and performance-based care.

A state-of-the-art review of quality-of-life assessment in venous disease.

OBJECTIVE: Chronic venous disease is a common condition and has a significant impact on patients' health status. Validated patient-reported outcome measures (PROMs) used to assess health status are needed to measure health status. This state-of-the-art review summarizes the current validation evidence for disease-specific PROMs for chronic venous disease and provides a framework for their use in the clinical setting. METHODS: A literature search in OVID Embase and Medline was conducted to identify relevant English-language studies of chronic venous disease that used disease-specific PROMs between January 1, 1993, and June 30, 2022. Abstracts and titles from identified studies were screened by four investigators, and full-text articles were subsequently screened for eligibility. Data on validation of disease-specific PROMs was abstracted from each included article. Classical test theory was used as a framework to examine a priori defined validation criteria for content validity, reliability (construct validity, internal reliability, and test-retest reliability), responsiveness, and expansion of the validation evidence base (use in randomized controlled trials and comparative effectiveness research, cultural or linguistic translations, predictive validity, or establishing the minimal clinically important difference threshold, defined as smallest amount an outcome or measure is perceived as a meaningful change to patients). The PROMs were categorized into three groups based on the manifestations of disease of the population for which they were developed. The overall validity of each PROM was assessed across three stages of validation including content validity (phase 1); construct validity, reliability, and responsiveness (phase 2); and expansion of the validation evidence base (phase 3). RESULTS: Of 2338 unique studies screened, 112 studies (4.8%) met inclusion criteria. The eight disease-specific PROMs identified were categorized into three groups: (1) overall chronic venous disease (C1 to C6); (2) C1 to C4 disease; and (3) C5 to C6 disease. Assessed by group, the Chronic Venous Insufficiency Questionnaire met criteria for validation at all three phases for patients with C1 to C4 disease, and the Charing Cross Venous Ulcer Questionnaire met criteria for validation at all three phases for patients with C5 to C6 disease. There were no PROMs that met all criteria for validation for use in overall chronic venous disease (C1 to C6). CONCLUSIONS: Of the eight PROMs assessed in this review, only two met prespecified criteria at each phase for validation. The Chronic Venous Insufficiency Questionnaire and Charing Cross Venous Ulcer Questionnaire should be considered for use in patients with chronic venous disease without venous ulcers and with venous ulcers, respectively.

Comparison of lower extremity bypass and peripheral vascular intervention for chronic limb-threatening ischemia in the Medicare-linked Vascular Quality Initiative.

OBJECTIVE: There is a relative lack of comparative effectiveness research on revascularization for patients with chronic limb-threatening ischemia (CLTI). We examined the association between lower extremity bypass (LEB) vs peripheral vascular intervention (PVI) for CLTI and 30-day and 5-year all-cause mortality and 30-day and 5-year amputation. METHODS: Patients undergoing LEB and PVI of the below-the-knee popliteal and infrapopliteal arteries between 2014 and 2019 were queried from the Vascular Quality Initiative, and outcomes data were obtained from the Medicare claims-linked Vascular Implant Surveillance and Interventional Outcomes Network database. Propensity scores were calculated on 15 variables using a logistic regression model to control for imbalances between treatment groups. A 1:1 matching method was used. Kaplan-Meier survival curves and hierarchical Cox proportional hazards regression with a random intercept for site and operator nested in site to account for clustered data compared 30-day and 5-year all-cause mortality between groups. Thirty-day and 5-year amputation were subsequently compared using competing risk analysis to account for the competing risk of death. RESULTS: There was a total of 2075 patients in each group. The overall mean age was 71 ± 11 years, 69% were male, and 76% were white, 18% were black, and 6% were of Hispanic ethnicity. Baseline clinical and demographic characteristics in the matched cohort were balanced between groups. There was no association between all-cause mortality over 30 days and LEB vs PVI (cumulative incidence, 2.3% vs 2.3% by Kaplan Meier; log-rank P-value = .906; hazard ratio [HR], 0.95; 95% confidence interval [CI], 0.62-1.44; P-value = .80). All-cause mortality over 5 years was lower for LEB vs PVI (cumulative incidence, 55.9% vs 60.1% by Kaplan Meier; log-rank P-value < .001; HR, 0.77; 95% CI, 0.70-0.86; P-value < .001). Accounting for competing risk of death, amputation over 30 days was also lower in LEB vs PVI (cumulative incidence function, 1.9% vs 3.0%; Fine and Gray P-value = .025; subHR, 0.63; 95% CI, 0.42-0.95; P-value = .025). There was no association between amputation over 5 years and LEB vs PVI (cumulative incidence function, 22.6% vs 23.4%; Fine and Gray P-value = .184; subHR, 0.91; 95% CI, 0.79-1.05; P-value = .184). CONCLUSIONS: In the Vascular Quality Initiative-linked Medicare registry, LEB vs PVI for CLTI was associated with a lower risk of 30-day amputation and 5-year all-cause mortality. These results will serve as a foundation to validate recently published randomized controlled trial data, and to broaden the comparative effectiveness evidence base for CLTI.

Obesity prevalence and variability in management practices for patients with symptomatic peripheral artery disease.

Obesity has been associated with poor disease outcomes in patients with lower extremity peripheral arterial disease (PAD). Given evolving treatments for obesity, evaluating its prevalence and treatment practices are key to develop a holistic management of PAD. We aimed to examine prevalence of obesity and variability of management strategies in symptomatic PAD patients enrolled in the international multicenter PORTRAIT registry from 2011 to 2015. Obesity management strategies studied included weight and/or dietary counseling and prescription of weight loss medications (orlistat, lorcaserin, phentermine-topiramate, naltrexone-buproprion, and liraglutide). Use frequency of obesity management strategies were calculated by country and compared across centers using adjusted median odds ratios (MOR). Of 1002 patients included, 36 % had obesity. No patients received weight loss medications. Weight and/or dietary counseling was prescribed in only 20 % of patients with obesity with significant variability in practices between centers (range 0.0-39.7 %; MOR 3.6, 95 % CI 2.04-9.95, p = < 0.001). In conclusion, obesity is a prevalent modifiable comorbidity in PAD that is hardly addressed during PAD management, with significant variability across practices. As obesity prevalence rates are growing, along with treatment modalities to treat it, especially in those with PAD, building systems to integrate systematic evidence-based weight and dietary management strategies in PAD are essential to close this gap in care.

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.

Drug-Coated Balloon and Drug-Eluting Stent Safety in Patients With Femoropopliteal and Severe Chronic Kidney Disease.

Background Patients with severe-stage chronic kidney disease (CKD) were excluded from femoropopliteal disease trials evaluating drug-coated balloons (DCBs) and drug-eluting stents (DESs) versus plain balloon angioplasty (POBA) and bare metal stents (BMSs). We examined the interaction between CKD status and device type for the association with 24-month all-cause mortality and major amputation risk. Methods and Results We studied patients undergoing femoropopliteal interventions (September 2016-December 2018) from Medicare-linked VQI (Vascular Quality Initiative) registry data. We compared outcomes for: (1) early-stage CKD (stages 1-3) receiving DCB/DES, (2) early-stage CKD receiving POBA/BMS, (3) severe-stage (4 and 5) CKD receiving DCB/DES, and (4) severe-stage CKD receiving POBA/BMS. We studied 8799 patients (early-stage CKD: 94%; severe-stage: 6%). DCB/DES use was 57% versus 51% in patients with early-stage versus severe-stage CKD. Twenty-four-month mortality risk for patients with early-stage CKD receiving DCB/DES (reference) was 21% versus 28% (hazard ratio [HR], 1.47 [95% CI, 1.31-1.65]) for those receiving POBA/BMS; patients with severe-stage CKD: those receiving DCB/DES had a 49% (HR, 2.61 [95% CI, 2.06-3.31]) mortality risk versus 52% (HR, 3.64 [95% CI, 2.91-4.55]) for those receiving POBA/BMS (interaction P<0.001). Adjusted analyses attenuated these results. For severe-stage CKD, DCB/DES versus POBA/BMS mortality risk was not significant at 24 months (post hoc comparison P=0.06) but was higher for the POBA/BMS group at 18 months (post hoc P<0.05). Patients with early-stage CKD receiving DCB/DES had the lowest 24-month amputation risk (6%), followed by 11% for early-stage CKD-POBA/BMS, 15% for severe-stage CKD-DCB/DES, and 16% for severe-stage CKD-POBA/BMS (interaction P<0.001). DCB/DES versus POBA/BMS amputation rates in patients with severe-stage CKD did not differ (post hoc P=0.820). Conclusions DCB/DES versus POBA/BMS use in patients with severe-stage CKD was associated with lower mortality and no difference in amputation outcomes.

Guideline-Directed Medical Therapy and Long-Term Mortality and Amputation Outcomes in Patients Undergoing Peripheral Vascular Interventions.

BACKGROUND: Lack of guideline-directed medical therapy (GDMT) in patients undergoing peripheral vascular interventions (PVIs) may increase mortality and amputation risk. OBJECTIVES: The authors sought to study the association between GDMT and mortality/amputation and to examine GDMT variability among providers and health systems. METHODS: We performed an observational study using patients in the Vascular Quality Initiative registry undergoing PVI between 2017 and 2018. Two-year all-cause mortality and major amputation data were derived from Medicare claims data. Compliance with GDMT was defined as receiving a statin, antiplatelet therapy, and angiotensin-converting enzyme inhibitor/angiotensin receptor blocker if hypertensive. Propensity 1:1 matching was applied for GDMT vs no GDMT and survival analyses were performed to compare outcomes between groups. RESULTS: Of 15,891 patients undergoing PVIs, 48.8% received GDMT and 6,120 patients in each group were matched. Median follow-up was 9.6 (IQR: 4.5-16.2) months for mortality and 8.4 (IQR: 3.5-15.4) for amputation. Mean age was 72.0 ± 9.9 years. Mortality risk was higher among patients who did not receive GDMT versus those on GDMT (31.2% vs 24.5%; HR: 1.37, 95% CI: 1.25-1.50; P < 0.001), as well as, risk of amputation (16.0% vs 13.2%; HR: 1.20; 95% CI: 1.08-1.35; P < 0.001). GDMT rates across sites and providers ranging from 0% to 100%, with lower performance translating into higher risk. CONCLUSIONS: Almost one-half of the patients receiving PVI in this national quality registry were not on GDMT, and this was associated with increased risk of mortality and major amputation. Quality improvement efforts in vascular care should focus on GDMT in patients undergoing PVI.

Patient-level and external factors in the use of drug-coated balloons and drug-eluting stents in femoropopliteal endovascular interventions.

OBJECTIVE: Drug-coated balloons (DCB) and drug-eluting stents (DES) have been rapidly adopted for femoropopliteal endovascular interventions due to their favorable patency rates. It is unclear whether choice of using drug coated devices versus bare metal stents (BMS) or plain balloon angioplasty (POBA) as primary treatment in femoropopliteal disease is mostly associated with patient-level factors, safety concerns, or by operator preferences. This study sought to evaluate factors associated with their use in a contemporary dataset. METHODS: All femoropopliteal lesions treated with endovascular interventions between 2016 and 2019 from the Vascular Quality Initiative registry were included. For each procedure, a primary treatment was identified based on the following hierarchy: DES > DCB > BMS > POBA. A hierarchical logistic regression model predicting DCB or DES use included patient-level characteristics, key events (period after Centers for Medicare and Medicaid Services reimbursement change, January 2018 [vs before] and period after Katsanos meta-analysis December 2018 [vs before]), and random effects for site and operator. Operator-level variability for DCB and DES use was summarized with an adjusted median odds ratio (MOR). RESULTS: A total of 57,753 femoropopliteal endovascular procedures were included. Poor functional status (odds ratio [OR], 0.92; 95% confidence interval [CI], 0.90-0.94), prior anticoagulant use (OR, 0.92; 95% CI, 0.87-0.97), higher Rutherford classification (OR, 0.86; 95% CI, 0.84-0.88), chronic kidney disease stage 4 or 5 (OR, 0.92; 95% CI, 0.86-0.98), and the period after the Katsanos meta-analysis publication (OR, 0.3; 95% CI, 0.29-0.32) were associated with a lower odds of DCB or DES use; whereas female sex (OR, 1.12; 95% CI,1.08-1.17), prior lesion treatment (OR, 1.17; 95% CI, 1.11-1.22), diabetes (OR, 1.07; 95% CI, 1.02-1.12), Trans-Atlantic Inter-Society Consensus class B (OR, 1.16; 95% CI, 1.09-1.24) and C (OR, 1.2; 95% CI, 1.12-1.28), and the period after the Centers for Medicare and Medicaid Services reimbursement change (OR, 1.08; 95% CI, 1.03-1.14) were associated with a higher odds of DCB or DES use. Significant variability in use was found across operators (adjusted MOR, 2.70; 95% CI, 2.55-2.85) and centers (adjusted MOR, 2.89; 95% CI, 2.50-3.27). CONCLUSIONS: DCB or DES use in femoropopliteal disease demonstrates wide variability across operators and is linked strongly with external factors, followed by anatomic lesion characteristics and a history of previous interventions. Future work needs to focus on tailoring DCB or DES use to patient and lesion characteristics and to develop appropriate use guidelines integrating these factors.

The shifting care and outcomes for patients with endangered limbs - Critical limb ischemia (SCOPE-CLI) registry overview of study design and rationale.

BACKGROUND: Critical limb ischemia (CLI), the most severe form of peripheral artery disease, is associated with pain, poor wound healing, high rates of amputation, and mortality (>20% at 1 year). Little is known about the processes of care, patients' preferences, or outcomes, as seen from patients' perspectives. The SCOPE-CLI study was co-designed with patients to holistically document patient characteristics, treatment preferences, patterns of care, and patient-centered outcomes for CLI. METHODS: This 11-center prospective observational registry will enroll and interview 816 patients from multispecialty, interdisciplinary vascular centers in the United States and Australia. Patients will be followed up at 1, 2, 6, and 12 months regarding their psychosocial factors and health status. Hospitalizations, interventions, and outcomes will be captured for 12 months with vital status extending to 5 years. Pilot data were collected between January and July of 2021 from 3 centers. RESULTS: A total of 70 patients have been enrolled. The mean age was 68.4 ± 11.3 years, 31.4% were female, and 20.0% were African American. CONCLUSIONS: SCOPE-CLI is uniquely co-designed with patients who have CLI to capture the care experiences, treatment preferences, and health status outcomes of this vulnerable population and will provide much needed information to understand and address gaps in the quality of CLI care and outcomes.ClinicalTrials.gov identifier (NCT Number): NCT04710563 https://clinicaltrials.gov/ct2/show/NCT04710563.