Socioeconomic and hospital-related predictors of amputation for critical limb ischemia

The association between socioeconomic distress communities index and amputation among patients with peripheral artery disease

Background

Socioeconomic factors have been shown to be associated with amputation in peripheral artery disease (PAD); however, analyses have normally focused on insurance status, race, or median income. We sought to determine whether community-level socioeconomic distress was associated with major amputation and if that association differed by race.

Materials and methods

Community-level socioeconomic distress was measured using the distressed communities index (DCI). The DCI is a zip code level compositive socioeconomic score (0-100) that accounts for unemployment, education level, poverty rate, median income, business growth, and housing vacancies. A distressed community was defined as a zip code with DCI of 40 or greater. We calculated one-year risk of major amputation by DCI score for individuals with peripheral artery disease in South Carolina, 2012-2017. Treating death as competing event, we reported Fine and Gray subdistribution hazards ratios (sdHR), adjusted for patient demographic and clinical comorbidities associated with amputation. Further analyses were completed to identify potential differences in outcomes within strata of race and DCI.

Results

Among 82,848 individuals with peripheral artery disease, the one-year incidence of amputation was 3.5% (95% CI: 3.3%, 3.6%) and was significantly greater in distressed communities than non-distressed communities (3.9%; 95% CI: 3.8%, 4.1% vs. 2.4%; 95% CI: 2.2%, 2.6%). After controlling for death and adjusting for covariates, we found an increased hazard of amputation among individuals in a distressed community (sdHR: 1.25; 95% CI: 1.14, 1.37), which persisted across racial strata. However, regardless of DCI score, Black individuals had the highest incidence of amputation.

Conclusion

Socioeconomic status is independently predictive of limb amputation after controlling for demographic characteristics and clinical comorbidities. Race continues to be an important risk factor, with Black individuals having higher incidence of amputation, even in non-distressed communities, than White individuals had in distressed communities.

Neurorehabilitation in Adults With Traumatic Upper Extremity Amputation: A Scoping Review

BACKGROUND

Most of the current literature around amputation focuses on lower extremity amputation or engineering aspects of prosthetic devices. There is a need to more clearly understand neurobehavioral mechanisms related to upper extremity amputation and how such mechanisms might influence recovery and utilization of prostheses.

OBJECTIVE

This scoping review aims to identify and summarize the current literature on adult traumatic upper limb amputation in regard to recovery and functional outcomes and how neuroplasticity might influence these findings.

METHODS

We identified appropriate articles using Academic Search Complete EBSCO, OVID Medline, and Cochrane databases. The resulting articles were then exported, screened, and reviewed based on Preferred Reporting Items for Systematic Reviews and Meta-Analyses for Scoping Reviews (PRISMA-ScR) guidelines.

RESULTS

Eleven (11) studies met the study criteria. Of these studies, 7 focused on sensory involvement, 3 focused on neuroplastic changes post-amputation related to functional impact, and 1 study focused on motor control and learning post-amputation. Overall, these studies revealed an incomplete understanding of the neural mechanisms involved in motor rehabilitation in the central and peripheral nervous systems, while also demonstrating the value of an individualized approach to neurorehabilitation in upper limb loss.

CONCLUSIONS

There is a gap in our understanding of the role of neurorehabilitation following amputation. Overall, focused rehabilitation parameters, demographic information, and clarity around central and peripheral neural mechanisms are needed in future research to address neurobehavioral mechanisms to promote functional recovery following traumatic upper extremity amputation.

Social determinants of diabetes-related foot disease among older adults in New South Wales, Australia: evidence from a population-based study

BACKGROUND

Diabetes-related foot is the largest burden to the health sector compared to other diabetes-related complications in Australia, including New South Wales (NSW). Understanding of social determinants of diabetes-related foot disease has not been definitive in Australian studies. This study aimed to investigate the social determinants of diabetes-related foot disease in NSW.

METHODOLOGY

The first wave of the 45 and Up Study survey data was linked with NSW Admitted Patient Data Collection, Emergency Department Data Collection, and Pharmaceutical Benefits Scheme data resulting in 28,210 individuals with diabetes aged 45 years and older in NSW, Australia. Three outcome variables were used: diabetes-related foot disease (DFD), diabetic foot ulcer (DFU), and diabetic foot infection (DFI). They were classified as binary, and survey logistic regression was used to determine the association between each outcome measure and associated factors after adjusting for sampling weights.

RESULTS

The prevalence of DFD, DFU and DFI were 10.8%, 5.4% and 5.2%, respectively, among people with diabetes. Multivariate analyses revealed that the common factors associated with DFD, DFU and DFI were older age (75 years or more), male, single status, background in English speaking countries, and coming from lower-income households (less than AUD 20,000 per year). Furthermore, common lifestyle and health factors associated with DFD, DFU, and DFI were low physical activity (< 150 min of moderate-to-vigorous physical activity per week), history of diabetes for over 15 years, and having cardiovascular disease.

CONCLUSION

Our study showed that about 1 in 10 adults with diabetes aged 45 years and older in NSW reported DFD. Interventions, including the provision of related health services aimed at reducing all forms of DFD in NSW, are recommended to target older individuals with a long history of diabetes, and coming from lower-income households.

Social Deprivation and the Association With Survival Following Fenestrated Endovascular Aneurysm Repair

BACKGROUND

Social deprivation is associated with poor clinical outcomes. It is known to have an impact on length of stay and post-operative mortality across a number of other surgical specialties. This study evaluates the impact of social deprivation on outcomes following fenestrated endovascular aneurysm repair (FEVAR).

METHODS

All elective FEVARs performed between 2010 and 2018 at a tertiary vascular center were analyzed. Deprivation (index of multiple deprivation [IMD]) data was sourced from the English indices of deprivation 2019, by postcode. Primary outcome was overall survival by Kaplan-Meier. Secondary outcomes included length of hospital stay (LOS) and complications. Cox-proportional hazard analyses were conducted.

RESULTS

Some 132 FEVAR patients were followed-up for 3.7 (SD 2.2) years. Fifty-seven patients lived in areas with high levels of deprivation (IMD 1-3), 34 in areas with moderate deprivation (IMD 4-6) and 41 in areas with the lowest level (IMD 7-10) of deprivation. Groups were comparable for Age, BMI, AAA diameter and co-morbidity. A higher proportion of patients from deprived areas had renal failure (15% [26.3%] vs. 9% [11.8%] P = 0.019) but no overall difference in procedure time was observed (200 min [155-250] vs. 180 min [145-240] P = 0.412). Kaplan-Meier analysis demonstrated significantly poorer survival for patients living in areas with high levels of deprivation (IMD 1-3) (P = 0.03). Mortality was comparable for IMD 4-6 and 7-10 groups. Patients from the most deprived areas had longer hospital stay (6 days [4-9] vs. 5 [3-7] P = 0.005) and higher all-cause complication rates (21 [36.8%] vs. 14 [18.4%] P = 0.02). Decreasing IMD was associated with worse survival (HR -0.85 [0.75-0.97] [P = 0.02]).

CONCLUSIONS

Social deprivation was associated with increased mortality, length of stay and all-cause complication rates in patients undergoing FEVAR for complex abdominal aortic aneurysm (AAA). These results may help direct preoptimization measures to improve outcomes in higher risk sub-groups.

Racial disparities in surgical management and outcomes of acute limb ischemia in the United States

Background

Although significant racial disparities in the surgical management of lower extremity critical limb threatening ischemia have been previously reported, data on disparities in lower extremity acute limb ischemia are lacking.

Methods

The 2012–2018 National Inpatient Sample was queried for all adult hospitalizations for acute limb ischemia (N = 225,180). Hospital-specific observed-to-expected rates of major lower extremity amputation were tabulated. Multivariable logistic and linear models were developed to assess the impact of race on amputation and revascularization.

Results

Nonwhite race was associated with significantly increased odds of overall (adjusted odds ratio: 1.16, 95% confidence interval 1.06–1.28) and primary (adjusted odds ratio: 1.34, 95% confidence interval 1.17–1.53) major amputation, decreased odds of revascularization (adjusted odds ratio 0.79, 95% confidence interval 0.73–0.85), but decreased in-hospital mortality (adjusted odds ratio: 0.86, 95% confidence interval 0.74–0.99). The nonwhite group incurred increased adjusted index hospitalization costs (β: +$4,810, 95% confidence interval 3,280-6,350), length of stay (β: + 1.09 days, 95% confidence interval 0.70–1.48), and nonhome discharge (adjusted odds ratio: 1.15, 95% confidence interval 1.06–1.26).

Conclusion

Significant racial disparities exist in the management of and outcomes of lower extremity acute limb ischemia despite correction for variations in hospital amputation practices and other relevant hospital and patient characteristics. Whether the etiology lies primarily in patient, institution, or healthcare provider–specific factors has not yet been determined. Further studies of race-based disparities in management and outcomes of acute limb ischemia are warranted to provide effective and equitable care to all.

The influence of socioeconomic status on outcomes of lower extremity arterial reconstruction

OBJECTIVE

Although it has been shown that patient socioeconomic status (SES) is associated with the surgical treatments chosen for severe peripheral arterial disease (PAD), the association between SES and outcomes of arterial reconstruction have not been well-studied. The objective of this study was to determine if SES is associated with outcomes following lower extremity arterial reconstruction.

METHODS

Patients 40 years and older who had surgical revascularization for severe lower extremity PAD were identified in the Nationwide Readmissions Database, 2010 to 2014. Measures of SES including median household income (MHI) quartiles of patients' residential ZIP codes were extracted. Factors associated with repeat revascularization, subsequent major amputations, hospital mortality, and 30-day all-cause readmission were evaluated using multivariable regression analyses.

RESULTS

Of the 131,529 patients identified, the majority (61%) were male, and the average age was 69 years. On unadjusted analyses, subsequent amputations were higher among patients in the lowest MHI quartile compared with patients in the highest MHI quartile (13% vs 10%; overall P < .001). On multivariable analyses, compared with patients in the lowest quartile, those in the highest quartile had lower amputation (adjusted odds ratio [aOR], 0.70; 95% confidence interval (CI), 0.63-0.77; overall P < .001) and readmission (aOR, 0.91; 95% CI, 0.84-0.99; overall P = .028) rates. However, subsequent revascularization (aOR, 1.04; 95% CI, 0.94-1.15) and mortality (aOR, 1.01; 95% CI, 0.79-1.28) rates were not different across the groups.

CONCLUSIONS

Lower SES is associated with disproportionally worse outcomes following lower extremity arterial reconstruction for severe PAD. These data suggest that improving outcomes of lower extremity arterial reconstruction may involve addressing socioeconomic disparities.

Geographic and Socioeconomic Disparities in Major Lower Extremity Amputation Rates in Metropolitan Areas

Background Rates of major lower extremity amputation in patients with peripheral artery disease are higher in rural communities with markers of low socioeconomic status, but most Americans live in metropolitan areas. Whether amputation rates vary within US metropolitan areas is unclear, as are characteristics of high amputation rate urban communities. Methods and Results We estimated rates of major lower extremity amputation per 100 000 Medicare beneficiaries between 2010 and 2018 at the ZIP code level among ZIP codes with ≥100 beneficiaries. We described demographic characteristics of high and low amputation ZIP codes, and the association between major amputation rate and 3 ZIP code-level markers of socioeconomic status-the proportion of patients with dual eligibility for Medicaid, median household income, and Distressed Communities Index score-for metropolitan, micropolitan, and rural ZIP code cohorts. Between 2010 and 2018, 188 995 Medicare fee-for-service patients living in 31 391 ZIP codes with ≥100 beneficiaries had a major lower extremity amputation. The median (interquartile range) ZIP code-level number of amputations per 100 000 beneficiaries was 262 (75-469). Though nonmetropolitan ZIP codes had higher rates of major amputation than metropolitan areas, 78.2% of patients undergoing major amputation lived in metropolitan areas. Compared with ZIP codes with lower amputation rates, top quartile amputation rate ZIP codes had a greater proportion of Black residents (4.4% versus 17.5%, P<0.001). In metropolitan areas, after adjusting for clinical comorbidities and demographics, every $10 000 lower median household income was associated with a 4.4% (95% CI, 3.9-4.8) higher amputation rate, and a 10-point higher Distressed Communities Index score was associated with a 3.8% (95% CI, 3.4%-4.2%) higher amputation rate; there was no association between the proportion of patients eligible for Medicaid and amputation rate. These findings were comparable to the associations identified across all ZIP codes. Conclusions In metropolitan areas, where most individuals undergoing lower extremity amputation live, markers of lower socioeconomic status and Black race were associated with higher rates of major lower extremity amputation. Development of community-based tools for peripheral artery disease diagnosis and management targeted to communities with high amputation rates in urban areas may help reduce inequities in peripheral artery disease outcomes.

Association of Cost Sharing With Delayed and Complicated Presentation of Acute Appendicitis or Diverticulitis

Question

Does an association exist between high cost-sharing insurance plans and patient presentation with and surgical management of acute appendicitis or acute diverticulitis?

Findings

In this cohort study of 151 852 patients, higher patient cost sharing was associated with lower odds of presenting with early, uncomplicated disease, receiving optimal surgical care, and receiving minimally invasive surgery.

Meaning

Policymakers should be aware of the clinical and financial implications of patient health care behaviors associated with increased cost sharing.

Importance

Treatment delays are associated with increased morbidity and cost of disease, although the extent to which cost sharing influences timely presentation and management of acute surgical disease remains unknown. Given recent policy changes using cost sharing to modify health care behavior, this study examines the association of cost sharing with the health of the patient at presentation and with receipt of optimal or minimally invasive surgery.

Objective

To assess whether cost sharing is associated with the likelihood of early, uncomplicated patient presentation or with surgical management of 2 representative emergency general surgery diagnoses: acute appendicitis and acute diverticulitis.

Design, Setting, and Participants

This cohort study used Health Care Cost Institute claims from January 1, 2013, through December 31, 2017, to analyze data of commercially insured individuals hospitalized for acute appendicitis or diverticulitis. In total, 151 852 patients in the data set aged 18 to 64 years and presenting with acute appendicitis or diverticulitis were included as identified using the International Classification of Diseases, Ninth Revision and the International Statistical Classification of Diseases and Related Health Problems, Tenth Revision. Data were analyzed from January 2020 through February 2021.

Exposures

The primary exposure was patient total cost sharing incurred for the index hospitalization, defined as their summed deductible, copayments, and coinsurance.

Main Outcomes and Measures

The primary outcome was early, uncomplicated disease presentation. Secondary outcomes were receipt of optimal surgical care and minimally invasive surgery if undergoing an operation. Analyses were conducted with multivariable logistic regression models to adjust for patient characteristics and community-level socioeconomic and geographic factors. High cost sharing was defined as quartile 4 (>$3082), and low cost sharing as quartile 1 ($0-$502).

Results

Among 151 852 patients, 52.4% were men, and the total cost-sharing median was $1725 (interquartile range, $503-$3082). Higher cost sharing was associated with lower odds of early, uncomplicated disease presentation (odds ratio, 0.63; 95% CI, 0.61-0.65). Patients with higher cost sharing were less likely to receive optimal surgical care (odds ratio, 0.96; 95% CI, 0.93-0.99) or minimally invasive surgery (odds ratio, 0.89; 95% CI, 0.84-0.95).

Conclusions and Relevance

The findings of this cohort study suggest that, as policymakers debate the degree of cost sharing in public and private insurance plans, attention should be given to the clinical and financial implications associated with care delays.

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.

Association between socioeconomic position and diabetic foot ulcer outcomes: a population-based cohort study in South Korea

Background

Low socioeconomic position (SEP) is associated with a high incidence of diabetic foot ulcers (DFUs). However, reports on the association between SEP and DFU outcomes are limited. Therefore, in this study, we investigated this association and determined the prognostic factors of DFU outcomes.

Methods

The total cohort comprised 976,252 individuals. Using probability sampling, we randomly selected a sample of patients by reviewing the data from the Health Insurance Review and Assessment Service database of South Korea during 2011–2015. Residence, household income, and insurance type represented SEP. The primary outcome was amputation, and the secondary outcome was mortality. A multivariate model was applied to identify the predictive factors. Amputation-free survival and overall survival were calculated using the Kaplan-Meier method.

Results

Among 976,252 individuals in the cohort, 1362 had DFUs (mean age 62.9 ± 12.2 years; 42.9% were women). Overall amputation and mortality rates were 4.7 and 12.3%, respectively. Male sex (hazard ratio [HR], 2.41; p < 0.01), low SEP (HR 5.13, 5.13; p = 0.018), ophthalmopathy (HR, 1.89; p = 0.028), circulatory complications (HR, 2.14; p = 0.020), and institutional type (HR, 1.78; p = 0.044) were prognostic factors for amputation. Old age (HR, 1.06; p < 0.01), low SEP (HR, 2.65; p < 0.01), ophthalmopathy (HR, 1.74; p < 0.01), circulatory complications (HR, 1.71; p < 0.01), and institution type (HR 1.84; p < 0.01) were predictors of mortality.

Conclusions

DFU patients with a low SEP are strongly associated with increased amputation and mortality rates. Along with age and comorbidities, SEP could provide the basis for risk assessment of adverse outcomes in DFU. Providing targeted care for this population considering SEP may improve the prognosis.

Racial and Ethnic Disparities in Peripheral Artery Disease

Peripheral artery disease is an obstructive, atherosclerotic disease of the lower extremities causing significant morbidity and mortality. Black Americans are disproportionately affected by this disease while they are also less likely to be diagnosed and promptly treated. The consequences of this disparity can be grim as Black Americans bear the burden of lower extremity amputation resulting from severe peripheral artery disease. The risk factors of peripheral artery disease and how they differentially affect certain groups are discussed in addition to a review of pharmacological and nonpharmacological treatment modalities. The purpose of this review is to highlight health care inequities and provide a review and resource of available recommendations for clinical management of all patients with peripheral artery disease.

Racial and ethnic disparities in coronary, vascular, structural, and congenital heart disease

Cardiovascular disease (CVD) remains the leading cause of death in the United States. However, percutaneous interventional cardiovascular therapies are often underutilized in Blacks, Hispanics, and women and may contribute to excess morbidity and mortality in these vulnerable populations. The Society for Cardiovascular Angiography and Interventions (SCAI) is committed to reducing racial, ethnic, and sex-based treatment disparities in interventional cardiology patients. Accordingly, each of the SCAI Clinical Interest Councils (coronary, peripheral, structural, and congenital heart disease [CHD]) participated in the development of this whitepaper addressing disparities in diagnosis, treatment, and outcomes in underserved populations. The councils were charged with summarizing the available data on prevalence, treatment, and outcomes and elucidating potential reasons for any disparities. Given the huge changes in racial and ethnic composition by age in the United States (Figure 1), it was difficult to determine disparities in rates of diagnosis and we expected to find some racial differences in prevalence of disease. For example, since the average age of patients undergoing transcatheter aortic valve replacement (TAVR) is 80 years, one may expect 80% of TAVR patients to be non-Hispanic White. Conversely, only 50% of congenital heart interventions would be expected to be performed in non-Hispanic Whites. Finally, we identified opportunities for SCAI to advance clinical care and equity for our patients, regardless of sex, ethnicity, or race.

Anxiety and Depression Scores in Patients Subjected to Arterial Revascularization for Critical Limb Ischemia

OBJECTIVES

This study aims to examine the changes in anxiety and depression scores in 138 patients with critical limb ischemia (rest pain or gangrene) who had no previous psychiatric history, at 30 days and 6 months after surgical revascularization.

METHODS

Patients were submitted to a questionnaire-based evaluation using the Beck Anxiety and Depression Inventories before surgery (no more than three days before surgery) ("Pre-Op"), 30 days after surgical revascularization ("Early PO") and at least 6 months after surgical revascularization ("Late PO"). The cut-off scores for depression were (1) < 10, no depression or minimal depression; (2) 10‒18, mild to moderate depression; (3) 19‒29, moderate to severe depression; and (4) 30‒63, severe depression. The cut-off scores for anxiety were (1) < 8, no anxiety or minimal anxiety; (2) 8‒15, mild anxiety; (3) 16‒25, moderate anxiety; and (4) 26‒63, severe anxiety.

RESULTS

No perioperative mortality was observed 30 days after surgical revascularization. Thirty-nine (28.2%) patients underwent major (above-ankle) amputation within 30 days. Mean anxiety and depression scores, respectively, declined from 12.48 ± 9.74 (mean ± SD) and 16.92 ± 12.48 preoperatively to 4.89 ± 7.04 and 6.52 ± 9.36 postoperatively (P<0.001, both). Anxiety and depression scores were not significantly affected by preoperative comorbidities (systemic arterial hypertension, diabetes mellitus, previous stroke, and smoking), affected arterial territory (aortoiliac, femoropopliteal, or infrapopliteal), or surgical technique (open surgery vs endovascular therapy). Only patients undergoing amputation within 30 days showed no improvement in depressive symptoms.

CONCLUSIONS

Patients with critical limb ischemia have a high incidence of anxiety and depressive symptoms, which improve considerably after successful surgical revascularization. Major amputation was associated with a lack of improvement in depression scores. A formal psychiatric evaluation may be beneficial in patients who show no improvement in depressive symptoms.

Reducing Nontraumatic Lower-Extremity Amputations by 20% by 2030: Time to Get to Our Feet: A Policy Statement From the American Heart Association

Nontraumatic lower-extremity amputation is a devastating complication of peripheral artery disease (PAD) with a high mortality and medical expenditure. There are ≈150 000 nontraumatic leg amputations every year in the United States, and most cases occur in patients with diabetes. Among patients with diabetes, after an ≈40% decline between 2000 and 2009, the amputation rate increased by 50% from 2009 to 2015. A number of evidence-based diagnostic and therapeutic approaches for PAD can reduce amputation risk. However, their implementation and adherence are suboptimal. Some racial/ethnic groups have an elevated risk of PAD but less access to high-quality vascular care, leading to increased rates of amputation. To stop, and indeed reverse, the increasing trends of amputation, actionable policies that will reduce the incidence of critical limb ischemia and enhance delivery of optimal care are needed. This statement describes the impact of amputation on patients and society, summarizes medical approaches to identify PAD and prevent its progression, and proposes policy solutions to prevent limb amputation. Among the actions recommended are improving public awareness of PAD and greater use of effective PAD management strategies (eg, smoking cessation, use of statins, and foot monitoring/care in patients with diabetes). To facilitate the implementation of these recommendations, we propose several regulatory/legislative and organizational/institutional policies such as adoption of quality measures for PAD care; affordable prevention, diagnosis, and management; regulation of tobacco products; clinical decision support for PAD care; professional education; and dedicated funding opportunities to support PAD research. If these recommendations and proposed policies are implemented, we should be able to achieve the goal of reducing the rate of nontraumatic lower-extremity amputations by 20% by 2030.

Disparities in amputation in patients with peripheral arterial disease

BACKGROUND

To describe peripheral arterial disease-related amputation as a marker for health disparities.

Epidemiology of peripheral artery disease

Peripheral artery disease (PAD) is the clinical manifestation of atherosclerosis that primarily affects peripheral arteries within the lower extremities. In this brief review, we describe the epidemiology and burden of disease of PAD within the United States, particularly among high-risk populations. Although the prevalence of PAD continues to increase and is typically higher among the elderly as well as men, women in lower socioeconomic strata are affected at rates two times that of men. Among racial/ethnic groups, Black and African-American patients both experience higher rates of disease as well as lower rates of access to preventative care. Moreover, despite an overall decrease in amputation rates among all patients with PAD, high-risk populations remain disproportionally affected. Specifically, patients in rural areas, African-American and Native-American patients, and those of low socioeconomic status carry the highest risk of amputation. Efforts to improve care among PAD patients should target these high-risk populations and offer comprehensive, evidence-based preventative care. Wide adoption and integration of these practices into comprehensive care models may help to mitigate amputation in the highest-risk populations. As our treatment pathways continue to evolve, we must place further emphasis on patient input and quality of life as we work toward continual improvement in the care of patients with PAD.

Association between race/ethnicity and the risk of amputation of lower extremities among medicare beneficiaries with diabetic foot ulcers and diabetic foot infections

INTRODUCTION

This study aimed to examine the association of race and ethnicity on the risk of lower extremity amputations among Medicare beneficiaries with diabetic foot ulcers (DFUs) and diabetic foot infections (DFIs).

RESEARCH DESIGN AND METHODS

A retrospective study included 2011-2015 data of a 5% sample of fee-for-service Medicare beneficiaries with a newly diagnosed DFU and/or DFI. The primary outcome was the time to the first major amputation episode after a DFU and/or DFI were identified using the diagnosis and procedure codes. We used multivariable Cox proportional hazards models to estimate the risk of time to the first major amputation across races, adjusting for sociodemographic and health status factors. Adjusted hazard ratios (aHRs) with a 95% CI were reported.

RESULTS

Among 92 929 Medicare beneficiaries newly diagnosed with DFUs and/or DFIs, 77% were whites, 14.3% African Americans (AAs), 3.3% Hispanics, 0.7% Native Americans (NAs), and 4.0% were other races. The incidence rates of major amputation were 0.02 person-years for NAs, 0.02 person-years for AAs, 0.01 person-years for Hispanics, 0.01 person-years for other races, and 0.01 person-years for whites (p<0.05). Multivariable analysis showed that AAs (aHR=1.9, 95% CI 1.7 to 2.2, p<0.0001) and NAs (aHR=1.8, 95% CI 1.3 to 2.6, p=0.001) were associated with an increased risk of major amputation compared with whites. Beneficiaries with DFUs and/or DFIs diagnosed by a podiatrist or primary care physician (aHR=0.7, 95% CI 0.6 to 0.8, p<0.0001, specialists as reference) or at an outpatient visit (aHR=0.3, 95% CI 0.3 to 0.3, p<0.0001, inpatient stay as reference) were associated with a decreased risk of major amputation.

CONCLUSIONS

Racial and ethnic disparities in the risk of lower extremity amputations appear to exist among fee-for-service Medicare beneficiaries with diabetic foot problems. AAs and NAs with DFUs and/or DFIs were associated with an increased risk of major amputations compared with white Medicare beneficiaries.

Epidemiology and Risk of Amputation in Patients With Diabetes Mellitus and Peripheral Artery Disease

Peripheral artery disease (PAD) stems from atherosclerosis of lower extremity arteries with resultant arterial narrowing or occlusion. The most severe form of PAD is termed chronic limb-threatening ischemia and carries a significant risk of limb loss and cardiovascular mortality. Diabetes mellitus is known to increase the incidence of PAD, accelerate disease progression, and increase disease severity. Patients with concomitant diabetes mellitus and PAD are at high risk for major complications, such as amputation. Despite a decrease in the overall number of amputations performed annually in the United States, amputation rates among those with both diabetes mellitus and PAD have remained stable or even increased in high-risk subgroups. Within this cohort, there is significant regional, racial/ethnic, and socioeconomic variation in amputation risk. Specifically, residents of rural areas, African-American and Native American patients, and those of low socioeconomic status carry the highest risk of amputation. The burden of amputation is severe, with 5-year mortality rates exceeding those of many malignancies. Furthermore, caring for patients with PAD and diabetes mellitus imposes a significant cost to the healthcare system-estimated to range from $84 billion to $380 billion annually. Efforts to improve the quality of care for those with PAD and diabetes mellitus must focus on the subgroups at high risk for amputation and the disparities they face in the receipt of both preventive and interventional cardiovascular care. Better understanding of these social, economic, and structural barriers will prove to be crucial for cardiovascular physicians striving to better care for patients facing this challenging combination of chronic diseases.

Digital Subtraction Angiography Prior to an Amputation for Critical Limb Ischemia (CLI): An Expert Recommendation Statement From the CLI Global Society to Optimize Limb Salvage

Despite recent guideline updates on peripheral artery disease (PAD) and critical limb ischemia (CLI) treatment, the optimal treatment for CLI is still being debated. As a result, care is inconsistent, with many CLI patients undergoing an amputation prior to what many consider to be mandatory: consultation with an interdisciplinary specialty care team and a comprehensive imaging assessment. More importantly, quality imaging is critical in CLI patients with below-the-knee disease. Therefore, the CLI Global Society has put forth an interdisciplinary expert recommendation for superselective digital subtraction angiography (DSA) that includes the ankle and foot in properly indicated CLI patients to optimize limb salvage. A recommended imaging algorithm for CLI patients is included.

One-Year Outcomes of Peripheral Endovascular Device Intervention in Critical Limb Ischemia Patients: Sub-Analysis of the LIBERTY 360 Study

Background

High-risk patients with advanced peripheral artery disease (PAD), including critical limb ischemia (CLI), are often excluded from peripheral endovascular device intervention clinical trials, leading to difficulty in translating trial results into real-world practice. There is a need for prospectively assessed studies to evaluate peripheral endovascular device intervention outcomes in CLI patients.

Methods

LIBERTY 360 is a prospective, observational, multi-center study designed to evaluate the procedural and long-term clinical outcomes of peripheral endovascular device intervention in real-world patients with symptomatic lower-extremity PAD. One thousand two hundred and four patients were enrolled and stratified based on Rutherford Classification (RC): RC2-3 (N=501), RC4-5 (N=603), and RC6 (N=100). For this sub-analysis, RC5 and RC6 patients (RC5-6; N=404) were pooled and 1-year outcomes were assessed.

Results

Procedural complications rarely (1.7%) resulted in post-procedural hospitalization and 89.1% of RC5-6 patients were discharged to home. Considering the advanced disease state in RC5-6 patients, there was a high freedom from 1-year major adverse event rate of 65.5% (defined as target vessel revascularization, death to 30 days, and major target limb amputation). At 1 year, freedom from major amputation was 89.6%. Wounds identified at baseline on the target limb had completely healed in 172/243 (70.8%) of the RC5-6 subjects by 1 year. Additionally, the overall quality of life, as measured by VascuQoL, improved from baseline to 1 year.

Conclusion

LIBERTY investigated real-world PAD patients with independent oversight of outcomes. This analysis of LIBERTY RC5-6 patients demonstrates that peripheral endovascular device intervention can be successful in CLI patients, with low rates of major amputation and improvement in wound healing and quality of life through 1-year follow-up.

LIBERTY 360, https://clinicaltrials.gov/ct2/show/NCT01855412, ClinicalTrials.gov Identifier: NCT01855412.

The effect of rurality on the risk of primary amputation is amplified by race

OBJECTIVE

Primary amputation (ie, without attempted revascularization) is a devastating complication of peripheral artery disease. Racial disparities in primary amputation have been described; however, rural disparities have not been well investigated. The purpose of this study was to examine the impact of rurality on risk of primary amputation and to explore the effect of race on this relationship.

METHODS

The national Vascular Quality Initiative amputation data set was used for analyses (N = 6795). The outcome of interest was primary amputation. Independent variables were race/ethnicity (non-Latinx whites vs nonwhites) and rural residence. Multivariable logistic regression examined impact of rurality and race/ethnicity on primary amputation after adjustment for relevant covariates and included an interaction for race/ethnicity by rural status.

RESULTS

Primary amputation occurred in 49% of patients overall (n = 3332), in 47% of rural vs 49% of urban patients (P = .322), and in 46% of whites vs 53% of nonwhites (P < .001). On multivariable analysis, nonwhites had a 21% higher odds of undergoing primary amputation overall (adjusted odds ratio [AOR], 1.21; 95% confidence interval [CI], 1.05-1.39). On subgroup analysis, rural nonwhites had two times higher odds of undergoing primary amputation than rural whites (AOR, 2.06; 95% CI, 1.53-2.78) and a 52% higher odds of undergoing primary amputation than urban nonwhites (AOR, 1.52; 95% CI, 1.19-1.94). In the urban setting, nonwhites had a 21% higher odds of undergoing primary amputation than urban whites (AOR, 1.21; 95% CI, 1.05-1.39).

CONCLUSIONS

In these analyses, rurality was associated with greater odds for primary amputation in nonwhite patients but not in white patients. The effect of race on primary amputation was significant in both urban and rural settings; however, the effect was significantly stronger in rural settings. These findings suggest that race/ethnicity has a compounding effect on rural health disparities and that strategies to improve health of rural communities need to consider the particular needs of nonwhite residents to reduce disparities.

Potentials, challenges, and limitations of the analysis of administrative data on vascular limb amputations in health care

Although more and more data on lower limb amputations are becoming available by leveraging the widening access to health care administrative databases, the applicability of these data for public health decisions is still limited. Problems can be traced back to methodological issues, how data are generated and to conceptual issues, namely, how data are interpreted in a multidimensional environment. The present review summarised all of the steps from converting the claims data of administrative databases into the analytical data and reviewed the wide array of sources of potential biases in the analysis of such data. The origins of uncertainty of administrative data analysis include uncontrolled confounding due to a lack of clinical data, the left- and right-censored nature of data collection, the non-standardized diagnosis/procedure-based data extraction methods (i.e., numerator/denominator problems) and additional methodological problems associated with temporal and spatial analyses. The existence of these methodological challenges in the administrative data-based analysis should not deter the analysts from using these data as a powerful tool in the armamentarium of clinical research. However, it must be done with caution and a thorough understanding and respect of the methodological limitations. In addition to this requirement, there is a profound need for pursuing further research on methodology and widening the search for other indicators (structural, process or outcome) that allow a deeper insight how the quality of vascular care may be assessed. Effective research using administrative data is based on strong collaboration in three domains, namely expertise in claims data handling and processing, the clinical field, and statistical analysis. The final interpretations of results and the countermeasures on the level of vascular care ought to be grounded on the integrity of research, open discussions and institutionalized mechanisms of science arbitration and honest brokering.

Is there a role for hyperbaric oxygen therapy in the treatment of refractory wounds of rare etiology?

INTRODUCTION

Delayed wound healing indicates wounds that have failed to respond to more than 4-6 weeks of comprehensive wound care. Wounds with delayed healing are a major source of morbidity and a major cost to hospital and community healthcare providers. Hyperbaric oxygen therapy (HBOT) is a treatment designed to increase the supply of oxygen to wounds and has been applied to a variety of wound types. This article reviews the place of HBOT in the treatment of non-healing vasculitic, calcific uremic arteriolopathy (CUA), livedoid vasculopathy (LV), pyoderma gangrenosum (PG) ulcers.

METHODS

We searched electronic databases for research and review studies focused on HBOT for the treatment of delayed healing ulcers with rare etiologies. We excluded HBOT for ulcers reviewed elsewhere.

RESULTS

We included a total of three case series and four case reports including 63 participants. Most were related to severe, non-healing ulcers in patients with vasculitis, CUA, LV, and PG. There was some evidence that HBOT may improve the healing rate of wounds by increasing nitric oxide (NO) levels and the number of endothelial progenitor cells in the wounds. HBOT may also improve pain in these ulcers.

CONCLUSION

We recommend the establishment of comprehensive and detailed wound care registries to rapidly collect prospective data on the use of HBOT for these problem wounds. There is a strong case for appropriately powered, multi-centre randomized trials to establish the true efficacy and cost-effectiveness of HBOT especially for vasculitis ulcers that have not improved following immunosuppressive therapy.

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.

The effect of income and insurance on the likelihood of major leg amputation

BACKGROUND

Although it has been suggested that individuals of low socioeconomic status and those with Medicaid or no insurance may be more likely to have their peripheral artery disease treated by leg amputation rather than by limb-saving revascularization, it is not clear if this disparity occurs consistently on a national basis, and if it does so in a linear fashion, such that poorer individuals are at progressively greater risk for amputation.

OBJECTIVE

We undertook this study to determine if lower median household income and Medicaid/no insurance status are associated with a higher risk for amputation, and if this occurs in a progressively linear fashion.

METHODS

The National (Nationwide) Inpatient Sample Database was queried to identify patients who were admitted with a diagnosis of critical limb ischemia from 2005 to 2014 and underwent either a major amputation or a revascularization procedure during that admission. Patients were stratified according to their insurance status and their median household income into four income quartiles. Multivariate logistic regression was performed to determine the effect of income and insurance status on the odds of undergoing amputation vs leg revascularization.

RESULTS

Across the different insurance types, there was a significant decrease in the odds ratios for amputation as one progressed from one MHI quartile to a higher one: namely, Medicare (2.23, 1.87, 1.65, and 1.42 for the first, second, third, and fourth MHI quartiles); Medicaid (2.50, 2.28, 2.04, and 1.80 for the first, second, third, and fourth MHI quartiles); private insurance (1.52, 1.21, 1.16, and 1.00 for the first, second, third, and fourth MHI quartiles), and uninsured (1.91, 1.64, 1.10, and 1.22, for the first, second, third, and fourth MHI quartiles).

CONCLUSIONS

Lower MHI, Medicaid insurance, and uninsured status are associated with a greater likelihood of amputation and a lower likelihood of undergoing limb-saving revascularization. These disparities are exacerbated in stepwise fashion, such that lower income quartiles are at progressively greater risk for amputation.

One-Year Results of the LIBERTY 360 Study: Evaluation of Acute and Midterm Clinical Outcomes of Peripheral Endovascular Device Interventions

Purpose: To report the 1-year results of a multicenter study of peripheral artery disease (PAD) treatment with a variety of endovascular treatment strategies employed in routine practice. Materials and Methods: The LIBERTY trial (ClinicalTrials.gov identifier NCT01855412) is a prospective, observational, core laboratory–assessed, multicenter study of endovascular device intervention in 1204 subjects (mean age 69.8±10.7 years; 770 men) stratified by Rutherford category (RC): claudicants (RC2,3; n=501) and critical limb ischemia (CLI) with no/minimal tissue loss (RC4,5; n=603) or significant tissue loss (RC6; n=100). Key outcomes included quality of life (QoL) measures (VascuQol and EuroQol) and freedom from major adverse events (MAE), defined as death (within 30 days), major amputation, and target vessel revascularization based on Kaplan-Meier analysis. Results: Successful revascularization was beneficial, with RC improvement noted across all groups. Thirty-day freedom from MAE estimates were high across all groups: 99.2% in RC2,3, 96.1% in RC4,5, and 90.8% in RC6. At 12 months, the freedom from MAE was 82.6% in RC2,3, 73.2% in RC4,5, and 59.3% in RC6 patients. Estimates for freedom from major amputation at 12 months were 99.3%, 96.0%, and 81.7%, respectively. QoL scores improved significantly across all domains in all groups with 12-month VascuQol total scores of 5.3, 5.0, and 4.8 for RC2,3, RC4,5, and RC6, respectively. Conclusion: The results indicate that peripheral endovascular intervention is a viable treatment option for RC2,3, RC4,5, and RC6 patients as evidenced by the high freedom from major amputation, as well as the improvement in QoL and the RC at 12 months. Furthermore, primary unplanned amputation is often not necessary in RC6.

Disparities in outcomes of patients admitted with diabetic foot infections

Objective

The purpose of this study was to evaluate the disparities in the outcomes of White, African American (AA) and non-AA minority (Hispanics and Native Americans (NA)), patients admitted in the hospitals with diabetic foot infections (DFIs).

Research design and methods

The HCUP-Nationwide Inpatient Sample (2002 to 2015) was queried to identify patients who were admitted to the hospital for management of DFI using ICD-9 codes. Outcomes evaluated included minor and major amputations, open or endovascular revascularization, and hospital length of stay (LOS). Incidence for amputation and open or endovascular revascularization were evaluated over the study period. Multivariable regression analyses were performed to assess the association between race/ethnicity and outcomes.

Results

There were 150,701 admissions for DFI, including 98,361 Whites, 24,583 AAs, 24,472 Hispanics, and 1,654 Native Americans (NAs) in the study cohort. Overall, 45,278 (30%) underwent a minor amputation, 9,039 (6%) underwent a major amputation, 3,151 underwent an open bypass, and 8,689 had an endovascular procedure. There was a decreasing incidence in major amputations and an increasing incidence of minor amputations over the study period (P < .05). The risks for major amputation were significantly higher (all p<0.05) for AA (OR 1.4, 95%CI 1.4,1.5), Hispanic (OR 1.3, 95%CI 1.3,1.4), and NA (OR 1.5, 95%CI 1.2,1.8) patients with DFIs compared to White patients. Hispanics (OR 1.3, 95%CI 1.2,1.5) and AAs (OR 1.2, 95%CI 1.1,1.4) were more likely to receive endovascular intervention or open bypass than Whites (all p<0.05). NA patients with DFI were less likely to receive a revascularization procedure (OR 0.6, 95%CI 0.3, 0.9, p = 0.03) than Whites. The mean hospital length of stay (LOS) was significantly longer for AAs (9.2 days) and Hispanics (8.6 days) with DFIs compared to Whites (8.1 days, p<0.001).

Conclusion

Despite a consistent incidence reduction of amputation over the past decade, racial and ethnic minorities including African American, Hispanic, and Native American patients admitted to hospitals with DFIs have a consistently significantly higher risk of major amputation and longer hospital length of stay than their White counterparts. Native Americans were less likely to receive revascularization procedures compared to other minorities despite exhibiting an elevated risk of an amputation. Further study is required to address and limit racial and ethnic disparities and to further promote equity in the treatment and outcomes of these at-risk patients.

Efficacy of Community-Based Exercise Therapy Among African American Patients With Peripheral Artery Disease: A Randomized Clinical Trial

IMPORTANCE

African American individuals are 2 times more likely than non-Hispanic white individuals to have peripheral artery disease (PAD). Structured community-based exercise therapy improves walking distance among patients with PAD, but these patients require motivation to adhere to therapy.

OBJECTIVE

To assess whether motivational interviewing (MI) is more efficacious than Patient-Centered Assessment and Counseling for Exercise (PACE) or control to improve walking distance in African American patients with PAD.

DESIGN, SETTING, AND PARTICIPANTS

In this 3-group randomized clinical trial, 174 African American patients with PAD were studied from May 1, 2012, to November 30, 2016, at health care centers, churches, and health fairs in Wichita, Kansas; Kansas City, Kansas, and Kansas City, Missouri.

INTERVENTIONS

Patients were randomized in a 1:1:1 fashion to 1 of 3 groups (57 to MI, 57 to PACE, and 60 to control). The 2 counseling interventions were delivered biweekly for 3 months and monthly for 3 months followed by a 6-month maintenance phase with limited contact. Control participants received a mailing at 3 and 9 months.

MAIN OUTCOMES AND MEASURES

The primary outcome was 6-month change in 6-minute walking performance. Secondary outcomes included 12-month change in walking performance and 6- and 12-month changes in quality of life.

RESULTS

A total of 174 African American patients (mean [SD] age, 64.2 [11.2] years; 128 [74.0%] female) were studied. At 6 months, mean (SE) change in walking distance by group was as follows: MI, -3.42 (4.55) m; PACE, 2.74 (6.00) m; and control, -0.18 (4.40) m. At 12 months, mean (SE) change in walking distance by group was as follows: MI, -7.75 (5.50) m; PACE, 13.75 (6.13) m; and control, -1.08 (5.73) m. Comparing each of the intervention arms (MI and PACE) with the control arm, no statistically significant increases in walking distance at 6 months (MI: change, -2.10 m; 95% CI, -16.54 to 12.35 m; PACE: change, 2.31 m; 95% CI, -11.36 to 15.97 m) or 12 months (MI: change, -5.56 m; 95% CI, -21.18 to 10.06 m; PACE: change, 14.24 m; 95% CI, -1.85 to 30.34 m) were found. Compared with MI, PACE resulted in a statistically significant increase in walking distance at 12 months of 19.80 m (95% CI, 3.33-36.28 m).

CONCLUSIONS AND RELEVANCE

In a cohort of African American patients with PAD, MI was not efficacious in improving walking distance at 6 or 12 months. The results of this study do not support the use of MI to improve walking performance in African American patients with PAD.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT01321086.

Racial Differences in the Effect of Granulocyte Macrophage Colony-Stimulating Factor on Improved Walking Distance in Peripheral Artery Disease: The PROPEL Randomized Clinical Trial

Background The effects of race on response to medical therapy in people with peripheral artery disease ( PAD ) are unknown. Methods and Results In the PROPEL (Progenitor Cell Release Plus Exercise to Improve Functional Performance in PAD) Trial, PAD participants were randomized to 1 of 4 groups for 6 months: supervised treadmill exercise+granulocyte-macrophage colony-stimulating factor ( GM - CSF ) (Group 1), exercise+placebo (Group 2), attention control+ GM - CSF (Group 3), or attention control+placebo (Group 4). Change in 6-minute walk distance was measured at 12- and 26-week follow-up. In these exploratory analyses, groups receiving GM - CSF (Groups 1 and 3), placebo (Groups 2 and 4), exercise (Groups 1 and 2), and attention control (Groups 2 and 4) were combined, maximizing statistical power for studying the effects of race on response to interventions. Of 210 PAD participants, 141 (67%) were black and 64 (30%) were white. Among whites, GM - CSF improved 6-minute walk distance by +22.0 m (95% CI : -4.5, +48.5, P=0.103) at 12 weeks and +44.4 m (95% CI : +6.9, +82.0, P=0.020) at 26 weeks, compared with placebo. Among black participants, there was no effect of GM - CSF on 6-minute walk distance at 12-week ( P=0.26) or 26-week (-5.0 m [-27.5, +17.5, P=0.66]) follow-up, compared with placebo. There was an interaction of race on the effect of GM - CSF on 6-minute walk change at 26-week follow-up ( P=0.018). Exercise improved 6-minute walk distance in black ( P=0.006) and white ( P=0.034) participants without interaction. Conclusions GM - CSF improved 6-minute walk distance in whites with PAD but had no effect in black participants. Further study is needed to confirm racial differences in GM - CSF efficacy in PAD . Clinical Trial Registration URL : http://www.clinicaltrials.gov . Unique identifier: NCT 01408901.

Risk Factors for Thirty-Day Readmissions After Lower Extremity Amputation in Patients With Vascular Disease

BACKGROUND

Understanding risk factors associated with readmission after lower extremity amputation may indicate targets for reducing readmission.

OBJECTIVE

To evaluate factors associated with all-cause 30-day readmission after lower extremity amputation procedures.

DESIGN

Retrospective cohort study.

SETTING

Inpatient.

PATIENTS

A total of 2480 patients who had lower extremity amputations between 2008 and 2014 were selected from national electronic medical record database, Cerner Health Facts.

METHODS

Univariate analysis of demographics, diagnoses, postoperative medications, and laboratory results were examined. Multivariate logistic regression models were used to identify characteristics independently associated with readmission overall and by amputation location-above the knee (AKA) or below the knee (BKA).

MAIN OUTCOME MEASUREMENT

Readmission within 30 days of discharge.

RESULTS

More than one half of patients (1403, 57%) underwent BKA and 1077 (43%) underwent AKA. Readmission within 30 days was 22% (24.1% BKA versus 19.4% AKA, P = .005). In multivariable logistic regression, factors associated with 30-day readmission after any amputation included BKA (odds ratio [OR] 1.41, 95% confidence interval [CI] 1.15-1.74, P = .001), hypertension (OR 1.70, 95% CI 1.33-2.16), surgical-site infections (OR 1.44, 95% CI 1.02-2.04), heart failure (OR 1.39, 95% CI 1.10-1.75), discharge to a skilled nursing facility (OR 1.88, 95% CI 1.41-2.51), and emergency/urgent procedures (OR 1.32, 95% CI 1.04-1.67). At readmission, 13.3% of patients with a BKA required an AKA revision, and 21.3% had a diagnosis of surgical-site infection.

CONCLUSIONS

Risk factors for readmission after any amputation included cardiac comorbidities, associated postoperative medications, and discharge to a skilled nursing facility. The finding that acute arterial embolism or thrombosis and a BKA during the index admission was highly associated with readmission, combined with the high rates of 30-day conversion to an AKA when readmitted, suggests these patients more often develop stump complications or may be undertreated during the initial hospitalization.

LEVEL OF EVIDENCE

III.

Association of Treatment for Critical Limb Ischemia with Gender and Hospital Volume

Critical limb ischemia (CLI) is a frequent and major vascular problem and can lead to amputation and death despite surgical revascularization. Women have been shown to have 3 to 4 per cent lower revascularization rates for CLI compared with men as well as inferior outcomes. We hypothesize that this difference is a result of women being more likely admitted to low-volume hospitals, which in turn perform fewer revascularizations. Prospective cohort study. Data from the Nationwide Inpatient Sample 2007 to 2010 were used to identify admissions with primary International Classification of Diseases-9 codes for CLI (International Classification of Diseases-9 codes: 440.22, 440.23, 440.24, 707.1, 707.10–707.15, or 707.19). Hospitals were grouped in quintiles by annual revascularization procedures. Bivariate analyses were performed and multivariable logistic regression was used to analyze the odds of revascularization, amputation, and mortality while controlling for patient and hospital-level factors. Of 113,631 admissions, 54,370 (47.8%) were women, who were more likely admitted to low-volume hospitals (very low: 49.6% vs very high: 47.1%; P < 0.001). Revascularization rates were lower in women (31.6% vs 35.1%, P < 0.001) across all volume quintiles, whereas the difference was greatest in the use of open surgical revascularization (12.5% vs 16.0%, P < 0.001). In multivariable analysis, female gender [odds ratio (OR) 0.87, 95% confidence interval (CI) 0.83–0.92, P < 0.001] and very-low hospital volume (OR 0.21, 95% CI 0.17–0.26, P < 0.001) were both significantly associated with lower rates of revascularization. Women had lower odds of major amputation compared with men (OR 0.75, 95% CI 0.69–0.82, P < 0.001), whereas treatment in a very high-volume hospital was associated with increased odds for amputation (OR 1.37, 95% CI 1.09–1.73, P = 0.008). Neither gender nor hospital volume were independently associated with in-hospital mortality in the multivariable regression model. Women are more likely to be admitted to low-volume hospitals for treatment of CLI. Because of this, they are less likely to undergo revascularization, although they also had lower rates of major amputation.

Racial and Socioeconomic Disparities After Carotid Procedures

Background:

Race has been associated with inferior outcomes after multiple procedures, but the association of socioeconomic status with procedures for cerebrovascular disease is not well established.

Materials and Methods:

Elective carotid artery stenting (CAS) and carotid endarterectomy (CEA) procedures were identified in the National Inpatient Sample, 2012 to 2014. Median household income was estimated from patient ZIP codes. Chi-square and multivariable logistic regression analysis evaluated outcomes, accounting for age, race, gender, comorbidities, procedure, income, insurance, and hospital characteristics.

Results:

We identified 234 825 carotid procedures (205 835 CEA and 28 990 CAS). Blacks and Hispanics were more likely to be among the lowest quartile income patients (LQIPs) compared to whites (53.5% and 38.7% vs 27.0%, respectively; P < .0002). Compared to highest income quartile patients, LQIP had lower rates of private insurance (16.3% vs 22.0%) and higher Medicaid use (4.7% vs 2.0%; all P < .0002). Lowest quartile income patients were more likely to receive CAS (odds ratio [OR] = 1.32, 95% confidence interval [CI]: 1.27-1.37), as were blacks and Hispanics (OR = 1.09, 95% CI: 1.02-1.26; OR = 1.31, 95% CI: 1.24-1.40, respectively). In multivariable regression, postoperative stroke was associated with LQIP, black race, and Hispanic ethnicity (OR = 1.16, 95% CI: 1.06-1.28; OR = 1.52, 95% CI: 1.33-1.73; OR = 1.43, 95% CI: 1.24-1.64, respectively). Subgroup analysis demonstrated that whites also had higher odds of stroke in the lower income quartile (OR = 1.2, 95% CI: 1.1-1.4). Mortality was associated with LQIP (OR = 1.6, 95% CI: 1.2-2.1), black race (OR = 1.8, 95% CI: 1.4-2.5), and CAS (OR = 1.3, 95% CI: 1.1-1.6). Length of stay in the lowest income quartile was longer than in patients with the highest income ( P < .0001).

Conclusions:

Race was associated with increased hospital mortality, postoperative stroke, and overall complications after carotid procedures. Lower income was significantly associated with increased stroke and mortality irrespective of race. Disparate utilization and outcomes for carotid procedures are multifactorial. Efforts to reduce disparities will need to focus on race and other socioeconomic factors.

Association of Human Immunodeficiency Virus Infection and Risk of Peripheral Artery Disease

BACKGROUND

The effect of human immunodeficiency virus (HIV) on the development of peripheral artery disease (PAD) remains unclear. We investigated whether HIV infection is associated with an increased risk of PAD after adjustment for traditional atherosclerotic risk factors in a large cohort of HIV-infected (HIV+) and demographically similar HIV-uninfected veterans.

METHODS

We studied participants in the Veterans Aging Cohort Study from April 1, 2003 through December 31, 2014. We excluded participants with known prior PAD or prevalent cardiovascular disease (myocardial infarction, stroke, coronary heart disease, and congestive heart failure) and analyzed the effect of HIV status on the risk of incident PAD events after adjusting for demographics, PAD risk factors, substance use, CD4 cell count, HIV-1 ribonucleic acid, and antiretroviral therapy. The primary outcome is incident peripheral artery disease events. Secondary outcomes include mortality and amputation in subjects with incident PAD events by HIV infection status, viral load, and CD4 count.

RESULTS

Among 91 953 participants, over a median follow up of 9.0 years, there were 7708 incident PAD events. Rates of incident PAD events per 1000 person-years were higher among HIV+ (11.9; 95% confidence interval [CI], 11.5-12.4) than uninfected veterans (9.9; 95% CI, 9.6-10.1). After adjustment for demographics, PAD risk factors, and other covariates, HIV+ veterans had an increased risk of incident PAD events compared with uninfected veterans (hazard ratio [HR], 1.19; 95% CI, 1.13-1.25). This risk was highest among those with time-updated HIV viral load >500 copies/mL (HR, 1.51; 95% CI, 1.38-1.65) and CD4 cell counts <200 cells/mm³ (HR, 1.91; 95% CI, 1.71-2.13). In contrast, HIV+ veterans with time updated CD4 cell count ≥500 cells/mm³ had no increased risk of PAD (HR, 1.03; 95% CI, 0.96-1.11). Mortality rates after incident PAD events are high regardless of HIV status. HIV infection did not affect rates of amputation after incident PAD events.

CONCLUSIONS

Infection with HIV is associated with a 19% increased risk of PAD beyond that explained by traditional atherosclerotic risk factors. However, for those with sustained CD4 cell counts <200 cells/mm³, the risk of incident PAD events is nearly 2-fold higher whereas for those with sustained CD4 cell counts ≥500 cells/mm³ there is no excess risk of incident PAD events compared with uninfected people.

The relation between household income and surgical outcome in the Dutch setting of equal access to and provision of healthcare

Background

The impact of socioeconomic disparities on surgical outcome in the absence of healthcare inequality remains unclear. Therefore, we set out to determine the association between socioeconomic status (SES), reflected by household income, and overall survival after surgery in the Dutch setting of equal access and provision of care. Additionally, we aim to assess whether SES is associated with cause-specific survival and major 30-day complications.

Methods

Patients undergoing surgery between March 2005 and December 2006 in a general teaching hospital in the Netherlands were prospectively included. Adjusted logistic and cox regression analyses were used to assess the independent association of SES–quantified by gross household income–with major 30-day complications and long-term postoperative survival.

Results

A total of 3929 patients were included, with a median follow-up of 6.3 years. Low household income was associated with worse survival in continuous analysis (HR: 1.05 per 10.000 euro decrease in income, 95% CI: 1.01–1.10) and in income quartile analysis (HR: 1.58, 95% CI: 1.08–2.31, first [i.e. lowest] quartile relative to the fourth quartile). Similarly, low income patients were at higher risk of cardiovascular death (HR: 1.26 per 10.000 decrease in income, 95% CI: 1.07–1.48, first income quartile: HR: 3.10, 95% CI: 1.04–9.22). Household income was not independently associated with cancer-related mortality and major 30-day complications.

Conclusions

Low SES, quantified by gross household income, is associated with increased overall and cardiovascular mortality risks among surgical patients. Considering the equality of care provided by this study setting, the associated survival hazards can be attributed to patient and provider factors, rather than disparities in healthcare. Increased physician awareness of SES as a risk factor in preoperative decision-making and focus on improving established SES-related risk factors may improve surgical outcome of low SES patients.

Race and Socioeconomic Status Independently Affect Risk of Major Amputation in Peripheral Artery Disease

Background

Black race has been shown to be a risk factor for amputation in peripheral artery disease (PAD); however, race has been argued to be a marker for socioeconomic status (SES) rather than true disparity. The aim of this study is to study the impact of race and SES on amputation risk in PAD patients.

Methods and Results

Patients with incident PAD in the national Veterans Affairs Corporate Data Warehouse were identified from 2003 to 2014 (N=155 647). The exposures were race and SES (measured by median income in residential ZIP codes). The outcome was incident major amputation. Black veterans were significantly more likely to live in low‐SES neighborhoods and to present with advanced PAD. Black patients had a higher amputation risk in each SES stratum compared with white patients. In Cox models (adjusting for covariates), black race was associated with a 37% higher amputation risk compared with white race (hazard ratio: 1.37; 95% confidence interval, 1.30–1.45), whereas low SES was independently predictive of increased risk of amputation (hazard ratio: 1.12; 95% confidence interval, 1.06–1.17) and showed no evidence of interaction with race. In predicted amputation risk analysis, black race and low SES continued to be significant risk factors for amputation regardless of PAD presentation.

Conclusions

Black race significantly increases the risk of amputation within the same SES stratum compared with white race and has an independent effect on limb loss after controlling for comorbidities, severity of PAD at presentation, and use of medications.

RACIAL AND GEOGRAPHIC VARIATION IN LEG AMPUTATIONS AMONG TEXANS

BACKGROUND

The existence of racial and ethnic disparities in leg amputations rates is well documented. Despite this, approaches to addressing these alarming disparities have been hampered by the inability to identify at-risk individuals in a region and design targeted interventions. We undertook this study to identify small geographic areas in which efforts focused on high-risk individuals with peripheral artery disease (PAD) could address disparities in leg amputation rates.

METHODS

We used de-identified Texas state admission data to identify PAD-related admissions associated with an initial revascularization (leg angioplasty or leg bypass) or an primary leg (above-ankle) amputation between from 2004 through 2009.

RESULTS

21,273 major initial procedures were performed in Texas from 2004 through 2009 for PAD-related diagnoses, including 16,898 revascularizations and 4,375 leg amputations. A multivariate logistic regression demonstrated that an initial leg amputations done without revascularization was significantly associated with, among other variables: people categorized as black (odds ratio [OR] 1.79) or Hispanic (OR 1.42); those with Medicaid coverage (OR 1.89); and those treated at low volume hospitals (OR 1.78; p<0.001 for all). Four geographic regions were identified with significantly higher risk-adjusted leg amputation rates. Of the 349 Texas hospitals performing major procedures, 72 (21%) reported no revascularization procedures during the six year period studied.

CONCLUSIONS

Prevention efforts directed at specific geographic areas may be more likely to reach at-risk people with PAD and thereby reduce leg amputations disparities in Texas. Such efforts might also find strategies to direct patients toward higher volume centers with higher revascularization rates.

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.

Controversies and evidence for cardiovascular disease in the diverse Hispanic population

OBJECTIVE

Hispanics account for approximately 17% of the U.S.

POPULATION

They are one of the fastest growing racial/ethnic groups, second only to Asians. This heterogeneous population has diverse socioeconomic conditions, making the prevention, diagnosis, and management of vascular disease difficult. This paper discusses the cultural, racial, and social aspects of the Hispanic community in the United States and assesses how they affect vascular disease within this population. Furthermore, it explores risk factors, medical and surgical treatments, and outcomes of vascular disease in the Hispanic population; generational evolution of these conditions; and the phenomenon called the Hispanic paradox.

METHODS

A systematic search of the literature was performed to identify all English-language publications from 1991 to 2014 using PubMed, which draws from the National Institutes of Health and U.S. National Library of Medicine, with the words "cardiovascular disease," "prevalence," "vascular," and "Hispanic." An additional search was performed using "cardiovascular disease and Mexico," "cardiovascular disease and Cuba," "cardiovascular disease and Puerto Rico," and "cardiovascular disease and Latin America" as well as for complications, management, outcomes, surgery, vascular disease, and Hispanic paradox. The resulting publications were queried for generational data (spanning multiple well-defined age groups) regarding cardiovascular disease, and cross-references were obtained from their bibliographies. Results are segmented by country of origin.

RESULTS

Compared with non-Hispanic whites, Hispanics face higher risks of cardiovascular diseases because of a high prevalence of high blood pressure, obesity, diabetes mellitus, and ischemic stroke. However, the incidence of peripheral arterial disease and carotid disease appears to be significantly lower than in whites. The Hispanic paradox (lower mortality in spite of higher cardiovascular risk factors) may relate to challenges in ascribing life expectancy and cause of death in this diverse population. Low socioeconomic status and high prevalence of concomitant diseases negatively influence the outcomes of all patients, independent of being Hispanic.

CONCLUSIONS

Understanding the cultural diversity in Hispanics is important in terms of targeting preventive measures to modify cardiovascular risk factors, which affect development and outcomes of vascular disease. The available literature regarding vascular disease in the Hispanic population is limited, and further longitudinal study is warranted to improve health care delivery and outcomes in this group.

Hospital readmissions after elective lower extremity vascular procedures

Background This study evaluated risk factors associated with 30-day readmission after open and endovascular lower extremity revascularization. Methods Patients admitted with peripheral artery disease and lower extremity procedures were selected from national electronic medical record data, Cerner Health Facts® (2008-2014). Thirty-day readmission was determined. Logistic regression models identified characteristics independently associated with readmission. Results There were 2781 open and 2611 endovascular procedures. Readmission was 10.9% (9.6% open versus 12.3% endovascular, p<.0001). Greater disease severity was associated with readmission for both groups. Readmission factors for lower extremity bypass: blood transfusions (OR 2.25, 95% CI 1.62-3.13), hyponatremia (OR 1.72, 95% CI 1.15-2.57), heart failure (OR 1.57, 95% CI 1.07-2.29), bronchodilators (OR 1.50, 95% CI 1.13-2.00), black race (OR 1.43, 95% CI 1.03-1.99), and hypokalemia (OR 0.43, 95% CI 0.20-0.95). Readmission factors for endovascular procedures: vasodilators (OR 1.63, 95% CI 1.22-2.16), end-stage renal disease (OR 1.43, 95% CI 1.02-2.01), fluid and electrolyte disorders (OR 1.44, 95% CI 1.00-2.06), hypertension (OR 1.33, 95% CI 0.99-1.76), coronary artery disease (OR 1.31, 95% CI 1.02-1.67), and diuretics (OR 1.30, 95% CI 1.01-1.70). Conclusions Readmission after lower extremity revascularization is associated with disease severity for both procedures. Factors associated with readmission following lower extremity bypass included heart failure, transfusions, hyponatremia, black race, and bronchodilator use. Risk factors for endovascular readmissions were often chronic conditions including coronary artery disease, kidney disease, hypertension, and hypertensive medications. Awareness of risk factors may help providers identify high-risk patients who may benefit from increased surveillance and programs to lower readmission.

Racial differences in functional decline in peripheral artery disease and associations with socioeconomic status and education

OBJECTIVE

The objective of this study was to determine whether blacks with lower extremity peripheral artery disease (PAD) have faster functional decline than whites with PAD.

METHODS

Participants with ankle-brachial index <0.90 were identified from Chicago medical centers and observed longitudinally. Mobility impairment and the 6-minute walk were assessed at baseline and every 6 to 12 months. Mobility loss was defined as becoming unable to walk up and down a flight of stairs or to walk ¼ mile without assistance.

RESULTS

Of 1162 PAD participants, 305 (26%) were black. Median follow-up was 46.0 months. Among 711 PAD participants who walked 6 minutes continuously at baseline, black participants were more likely to become unable to walk 6 minutes continuously during follow-up (64/171 [37.4%] vs 156/540 [28.9%]; log-rank, P = .006). Black race was associated with becoming unable to walk 6 minutes continuously, adjusting for age, sex, ankle-brachial index, comorbidities, and other confounders (hazard ratio, 1.45; 95% confidence interval, 1.05-1.99; P = .022). This association was attenuated after adjustment for income and education (P = .229). Among 844 participants without baseline mobility impairment, black participants had a higher rate of mobility loss (64/209 [30.6%] vs 164/635 [25.8%]; log-rank, P = .009). Black race was associated with increased mobility loss, adjusting for potential confounders (hazard ratio, 1.42; 95% confidence interval, 1.04-1.94; P = .028). This association was attenuated after additional adjustment for income and education (P = .392) and physical activity (P = .113). There were no racial differences in average annual declines in 6-minute walk, usual-paced 4-meter walking velocity, or fast-paced 4-meter walking velocity.

CONCLUSIONS

Black PAD patients have higher rates of mobility loss and becoming unable to walk for 6 minutes continuously. These differences appear related to racial differences in socioeconomic status and physical activity.

Outcomes for critical limb ischemia are driven by lower extremity revascularization volume, not distance to hospital

OBJECTIVE

The objective of this study was to identify relationships among geographic access to care, vascular procedure volume, limb preservation, and survival in patients diagnosed with critical limb ischemia (CLI).

METHODS

Using New York State administrative data from 2000 to 2013, we identified a patient's first presentation with CLI defined by International Classification of Diseases, Ninth Revision diagnosis and procedure codes. Distance from the patient's home to the index hospital was calculated using the centroids of the respective ZIP codes. A multivariable logistic regression model was employed to estimate the impact of distance, major lower extremity amputation (LEA) volume, and lower extremity revascularization (LER) volume on major amputation and 30-day mortality. Volumes and distances were analyzed in quintiles. The farthest distance quintile and the highest procedure volume quintiles were used as references for generating odds ratios (ORs).

RESULTS

There were 49,576 patients identified with an initial presentation of CLI. The median age was 73 years, 35,829 (73.2%) had Medicare as a primary insurer, 11,395 (23.0%) had a major amputation, and 4249 (8.6%) died within 30 days of admission. Patients in the closest distance quintile were more likely to undergo amputation (OR, 1.53 [1.39-1.68]; P < .0001). Patients who visited hospitals in the lowest LER volume quintile with at least one procedure per year faced higher 30-day mortality rates (OR, 2.05 [1.67-2.50]; P < .0001) and greater odds of amputation (OR, 9.94 [8.5-11.63]; P < .0001). Patients who visited hospitals in the lowest LEA volume quintile had lower odds of 30-day mortality (OR, 0.66 [0.50-0.87]; P = .0033) and lower odds of amputation (OR, 0.180 [0.142-0.227]; P < .0001).

CONCLUSIONS

Rates of major amputation are inversely associated with distance from the index hospital, whereas rates of both major amputation and mortality are inversely associated with LER volume. Rates of major amputation and mortality are directly associated with LEA volume. We believe that unless it is otherwise contraindicated, these data support consideration for selective referral of CLI patients to high-volume centers for LER regardless of distance. Within the context of value-based health care delivery, policy supporting regionalization of CLI care into centers of excellence may improve outcomes for these patients.

Phase Ib Safety, Two-Dose Study of MultiGeneAngio in Patients with Chronic Critical Limb Ischemia

Critical limb ischemia (CLI) is the most severe presentation of peripheral arterial disease. We developed cell-based therapy entailing intra-arterial injection of autologous venous endothelial cells (ECs) modified to express angiopoietin 1, combined with autologous venous smooth muscle cells (SMCs) modified to express vascular endothelial growth factor. This combination promoted arteriogenesis in animal models and was safe in patients with limiting claudication. In an open-label, phase Ib study, we assessed the safety and efficacy of this therapy in CLI patients who failed or were unsuitable for surgery or intravascular intervention. Of 23 patients enrolled, 18 with rest pain or non-healing ulcers (Rutherford categories 4 and 5) were treated according to protocol, and 5 with significant tissue loss (Rutherford 6) were treated under compassionate treatment. Patients were assigned randomly to receive 1 × 10⁷ or 5 × 10⁷ (EC-to-SMC ratio, 1:1) of the cell combination. One-year amputation-free survival rate was 72% (13/18) for Rutherford 4 and 5 patients; all 5 patients with Rutherford 6 underwent amputation. Of the 12 with unhealing ulcers at dosing, 6 had complete healing and 2 others had >66% reduction in ulcer size. Outcomes did not differ between the dose groups. No severe adverse events were observed related to the therapy.