Sex Differences in Management and Outcomes of Critical Limb Ischemia in the Medicare Population

Health Disparities Across the Spectrum of Amputation Care: A Review of Literature

Limb loss is a common and disabling experience for patients, frequently caused by critical limb ischemia or deterioration of chronic wounds. Disparities in outcomes for prevention of amputation, level of amputation, and postamputation outcomes have been described. Understanding the nature of these disparities and the populations most affected can help clinicians and policymakers target interventions and programs. This article reviews existing literature regarding disparities in amputation care, including prevention methods, surgical outcomes, and postamputation outcomes. The authors identified several potential racial, socioeconomic, and gender disparities, particularly affecting Black, Native American, and Latino/a/x patients, female gender, and those in rural settings.

Addressing Psychosocial Care Needs in Women with Peripheral Artery Disease

PURPOSE OF REVIEW

Peripheral artery disease (PAD) is a growing global epidemic. Women with PAD are at elevated risk of experiencing psychosocial stressors that influence the diagnosis, management, and course of their illness due to unique sex- and gender-based factors.

RECENT FINDINGS

We review existing evidence for increased psychosocial risk in women with PAD with a focus on mood disorders, chronic stress, pain experiences, substance use disorders, health behaviors and illness perceptions, and healthcare access. We discuss how these factors exacerbate PAD symptomatology and lead to adverse outcomes. Existing gaps in women's vascular care are reviewed and potential solutions to bridge these gaps through psychosocial care integration are proposed. Current care paradigms for women's vascular care do not adequately screen for and address psychosocial comorbidities. Clinician education, integration of evidence-based psychological care strategies, implementation of workflows for the management of individuals with PAD and mental health comorbidities, reform to reimbursement structures, and further advocacy are needed in this space. This review provides a construct for integrated behavioral health care for women with PAD and advocates for further integration of care.

Impact of hyperuricemia on 5-year clinical outcomes in patients with critical limb ischemia following percutaneous transluminal angioplasty

BACKGROUND

A growing evidence on the correlation between hyperuricemia and cardiovascular disease (CVD) has been previously reported. However, there have been limited data on the impact of hyperuricemia on long-term clinical outcomes in patients with critical limb ischemia (CLI) who underwent percutaneous transluminal angioplasty (PTA).

METHODS

A total of 425 peripheral artery disease patients who underwent PTA for CLI were enrolled. The patients were divided into the hyperuricemia group (n = 101) and the normal group (n = 324). The primary endpoint was major adverse cerebral and cardiovascular event (MACCE), including death, myocardial infarction, any coronary revascularization, and stroke, up to 5 years. The secondary endpoint was a major adverse limb event (MALE), including any repeated PTA, and target extremity surgery. Inverse probability weighting (IPTW) analysis, derived from the logistic regression model, was performed to adjust for potential confounders.

RESULTS

After IPTW matching analysis, compared to the normal group, the hyperuricemia group was associated with a higher incidence of MACCE (20.7% vs. 13.6%, hazard ratio [HR], 1.65; 95% confidence interval [CI], 1.15-2.38, P  = 0.006) including non-cardiac death (11.7% vs. 6.3%, HR: 1.95, 95% CI: 1.19-3.19, P  = 0.006) and MALE (47.7% vs. 36.0%, HR: 1.62, 95% CI: 1.23-2.13, P  = 0.001) including non-target extremity revascularization (15.0% vs. 6.8%, HR: 2.42, 95% CI: 1.52-3.84, P  < 0.001).

CONCLUSION

In the present study, hyperuricemia was associated with worse clinical outcomes in patients with CLI following PTA during 5-year clinical follow-up. Efficacy of controlling hyperuricemia in improving clinical outcomes should be evaluated in further studies.

Prescriber decision-making on antithrombotic therapy after endovascular intervention for peripheral artery disease: a protocol for a discrete choice experiment

INTRODUCTION

Peripheral artery disease (PAD) is a major risk factor for cardiovascular morbidity and mortality, despite surgical and endovascular treatments. Emerging evidence supports the use of immediate antithrombotic medications after endovascular intervention for PAD, however, there is a lack of consensus regarding choice and duration of antithrombotic therapy. Prescriber decision-making is a complex process, with prior studies demonstrating patient factors can influence variability in antithrombotic therapy for PAD. However, it remains unclear the relative contribution of these factors. This paper describes a planned study that aims to (1) determine the influence of patient factors on clinician preference for antithrombotic therapy following endovascular intervention and (2) compare differences in prescribing preferences between consultant vascular surgeons and trainees.

METHODS AND ANALYSIS

This cross-sectional survey will evaluate antithrombotic prescribing choices using a discrete choice experiment (DCE) that has been developed and piloted for this study. A list of attributes and levels was generated using a mixed-methods approach. This included an extensive literature review and semistructured interviews with prescribing clinicians. Following final selection of included attributes, specialised software was used to construct a D-efficient design for the DCE questionnaire. The electronic questionnaire will be administered to vascular trainees and consultant surgeons across Australia. These data will be analysed using multinomial logistic regression, treating the decision to prescribe antithrombotic therapy as a function of both the attributes of the two alternatives, as well as characteristics of the respondent. Latent class analysis will be used to explore heterogeneity of responses.

ETHICS AND DISSEMINATION

Ethics approval was obtained from the University of Sydney Human Ethics committee (2023/474). The results of this study will be published in peer-reviewed journals and presented at national vascular surgical conferences. These results will be used to improve understanding how clinicians make prescribing decisions and to inform future strategy to enhance guideline-directed prescribing.

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

OBJECTIVE

To identify disparities in sociodemographic factors that are associated with major lower limb amputation in patients with peripheral arterial disease (PAD).

METHODS

A systematic review of the literature was performed to identify studies that reported major lower limb amputation rates in patients with PAD among different sociodemographic groups. Data that compared amputation rates on the basis of sex, race, ethnicity, income, insurance, geography, and hospital type were collected and described. Outcomes were then aggregated and standardized, and a meta-analysis was performed to synthesis data into single odds ratios (ORs).

RESULTS

Forty-one studies were included in the review. There was no association found between males and females (OR, 0.95; 95% confidence interval [CI], 0.90-1.00). Compared with Whites, higher rates of amputation were seen among Blacks/African Americans (OR, 2.02; 95% CI, 1.81-2.26) and Native Americans (OR, 1.22; 95% CI, 1.04-1.45). No significant association was found between Whites and Asians, Native Hawaiians, or Pacific Islanders (OR, 1.15; 95% CI, 1.00-1.33). Hispanics had higher rates of amputation compared with non-Hispanics (OR, 1.36; 95% CI, 1.22-1.52). Compared with private insurance, higher rates of amputation were seen among Medicare patients (OR, 1.38; 95% CI, 1.27-1.50), Medicaid patients (OR, 1.59; 95% CI, 1.44-1.76), and noninsured patients (OR, 1.41; 95% CI, 1.02-1.95). Compared with the richest income quartile, higher rates of amputation were seen among the second income quartile (OR, 1.10; 95% CI, 1.05-1.15), third income quartile (OR, 1.20; 95% CI, 1.07-1.35), and bottom income quartile (OR, 1.36; 95% CI, 1.24-1.49). There was no association found between rural and urban populations (OR, 1.35; 95% CI, 0.92-1.97) or between teaching and nonteaching hospitals (OR, 1.01; 95% CI, 0.91-1.12).

CONCLUSIONS

Our study has identified a number of disparities and quantified the influence of sociodemographic factors on major lower limb amputation rates owing to PAD between groups. We believe these findings can be used to better target interventions aimed at decreasing amputation rates, although further research is needed to better understand the mechanisms behind our findings.

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

BACKGROUND

Lower-limb amputation rates in patients with chronic limb-threatening ischemia vary across the United States, with marked disparities in amputation rates by gender, race, and income status. We evaluated the association of patient, hospital, and geographic characteristics with the intensity of vascular care received the year before a major lower-limb amputation and how intensity of care associates with outcomes after amputation.

METHODS

Using Medicare claims data (2016-2019), beneficiaries diagnosed with chronic limb-threatening ischemia who underwent a major lower-limb amputation were identified. We examined patient, hospital, and geographic characteristics associated with the intensity of vascular care received the year before amputation. Secondary objectives evaluated all-cause mortality and adverse events following amputation.

RESULTS

Of 33 036 total Medicare beneficiaries undergoing major amputation, 7885 (23.9%) were due to chronic limb-threatening ischemia; of these, 4988 (63.3%) received low-intensity and 2897 (36.7%) received high-intensity vascular care. Mean age, 76.6 years; women, 38.9%; Black adults, 24.5%; and of low income, 35.2%. After multivariable adjustment, those of low income (odds ratio, 0.65 [95% CI, 0.58-0.72]; P<0.001), and to a lesser extent, men (odds ratio, 0.89 [95% CI, 0.81-0.98]; P=0.019), and those who received care at a safety-net hospital (odds ratio, 0.87 [95% CI, 0.78-0.97]; P=0.012) were most likely to receive low intensity of care before amputation. High-intensity care was associated with a lower risk of all-cause mortality 2 years following amputation (hazard ratio, 0.79 [95% CI, 0.74-0.85]; P<0.001).

CONCLUSIONS

Patients who were of low-income status, and to a lesser extent, men, or those cared for at safety-net hospitals were most likely to receive low-intensity vascular care. Low-intensity care was associated with worse long-term event-free survival. These data emphasize the continued disparities that exist in contemporary vascular practice.

A systematic review of disparities in the medical management of atherosclerotic cardiovascular disease in females

Atherosclerotic cardiovascular disease (ASCVD) is the leading cause of death in the United States and worldwide. Medical management of known modifiable risk factors, such as dyslipidemia, hypertension, and diabetes, is a key aspect to its treatment. Unfortunately, there are substantial sex-based differences in the treatment of ASCVD that result in poor medical management and worse clinical outcomes. The objective of this systematic review was to summarize known disparities in the medical management of ASCVD in females. We included prior studies with specific sex- and sex-based analyses regarding the medical treatment of the following three major disease entities within ASCVD: cerebrovascular disease, coronary artery disease, and peripheral artery disease. A total of 43 articles met inclusion criteria. In our analysis, we found that females were less likely to receive appropriate treatment of dyslipidemia or be prescribed antithrombotic medications. However, treatment differences for diabetes and hypertension by sex were not as clearly represented in the included studies. In addition to rectifying these disparities in the medical management of ASCVD, this systematic review highlights the need to address larger issues, such as underrepresentation of females in clinical trials, decreased access to care, and underdiagnosis of ASCVD to improve overall care for females.

Peripheral artery disease: Update on etiology, pathophysiology, diagnosis and treatment

Peripheral artery disease (PAD) is a condition related to atherosclerosis affecting >200 million people worldwide, and it increases cardiovascular morbidity (mainly from myocardial infarction and stroke) and mortality. Indeed, PAD patients are classified as patients at very high cardiovascular risk. The most common manifestation of PAD is intermittent claudication, which is associated with reduced mobility and leg pain. Nevertheless, asymptomatic PAD is the most frequent form of PAD worldwide; therefore, it remains underdiagnosed and undertreated. The major risk factors for PAD are smoking, diabetes mellitus, hyperlipidemia, hypertension, overweight/obesity, age, male sex, and black race. Hence, the first and most relevant approach in PAD treatment is lifestyle management, with measures such as smoking cessation, healthy diet, weight loss, and regular physical exercise. This should also be supported by an optimal pharmacological approach including lipid-lowering drugs, antihypertensive drugs, antidiabetic agents, and antithrombotics.

Gender Differences and Amputation Risk in Peripheral Artery Disease-A Single-Center Experience

Background and Objectives: Peripheral artery disease (PAD) affects both genders, but the knowledge of clinical and therapeutic aspects particular to each gender has a prognostic value, modulating the risk of amputation and helping to reduce the risk of death or the occurrence of an acute vascular event secondary to optimal management. Materials and Methods: We conducted a retrospective, descriptive study that included 652 patients with PAD who were evaluated at "St. Spiridon" Hospital's Cardiology Department and divided into two groups according to gender: women (100 cases) and men (552 cases). We evaluated demographics, anthropometric data, as well as clinical and paraclinical parameters in the two groups. Results: Men had a lower mean age (p < 0.001), higher mean BMI (p = 0.049) and were more frequent smokers. (p = 0.008). Hypercholesterolemia (p = 0.026), obesity (p = 0.009), concomitant cerebrovascular (p = 0.005) and chronic kidney disease (p = 0.046) were more common in women, while coronary artery disease (p = 0.033) was more common in men. The number of angiographic stenotic lesions (p = 0.037) is a statistically significant parameter in our study, with both genders predominantly associated with stenotic lesions. In addition, directly proportional relationships were found between smoking, uric acid, inflammatory markers, and the number of stenotic lesions and thromboses or the ankle-brachial index (ABI). In the subgroup of men, the number of stenotic and thrombosed lesions positively correlated with the ABI value (p < 0.001). The presence of more than three cardiovascular risk factors (p = 0.001) and serum triglyceride levels (p = 0.019) significantly correlated with the number of angiographically detected lesions. We applied several risk scores (PREVENT III, Finnvasc Score, or GermanVasc risk score) in our study group for prognostic purposes, without showing statistically significant differences between genders. Men, rest pain, gangrene, smoking status, the presence of more than three cardiovascular risk factors, or a serum HDL-cholesterol level below 40 mg/dL (p < 0.001 for all parameters) are independent predictors associated with amputation in our study group. Conclusions: In our study, we demonstrated that several clinical-paraclinical particularities guide the diagnosis, providing the clinician with prognostic and therapeutic tools to choose the optimal management with maximum benefits.

Sex-Related Differences in Patient Characteristics, Risk Factors, and Symptomatology in Older Adults with Pulmonary Embolism: Findings from the SERIOUS-PE Study

Sex-specific factors are implicated in pulmonary embolism (PE) presentation in young patients, as indicated by increased risk in pregnancy. Whether sex differences exist in PE presentation, comorbidities, and symptomatology in older adults, the age group in which most PEs occur, remains unknown. We identified older adults (aged ≥65 years) with PE in a large international PE registry replete with information about relevant clinical characteristics (RIETE registry, 2001-2021). To provide national data from the United States, we assessed sex differences in clinical characteristics and risk factors of Medicare beneficiaries with PE (2001-2019). The majority of older adults with PE in RIETE (19,294/33,462, 57.7%) and in the Medicare database (551,492/948,823, 58.7%) were women. Compared with men, women with PE less frequently had atherosclerotic diseases, lung disease, cancer, or unprovoked PE, but more frequently had varicose veins, depression, prolonged immobility, or history of hormonal therapy (p < 0.001 for all). Women less often presented with chest pain (37.3 vs. 40.6%) or hemoptysis (2.4 vs. 5.6%) but more often with dyspnea (84.6 vs. 80.9%) (p < 0.001 for all). Measures of clot burden, PE risk stratification, and use of imaging modalities were comparable between women and men. PE is more common in elderly women than in men. Cancer and cardiovascular disease are more common in men, whereas transient provoking factors including trauma, immobility, or hormone therapy are more common in elderly women with PE. Whether such differences correlate with disparities in treatment or differences in short- or long-term clinical outcomes warrants further investigation.

Contemporary Treatment and Outcome of Patients with Ischaemic Lower Limb Amputation: A Focus on Sex Differences

OBJECTIVE

Chronic limb threatening ischaemia (CLTI) has a devastating prognosis with high rates of lower limb amputation (LLA) and deaths. This is an illustration of contemporary management and the long term fate of patients after ischaemic LLA, particularly with respect to sex, using real world data.

METHODS

This was a multisectoral cross sectional and longitudinal analysis of health claims data from the largest German health insurance database (AOK). Data of 39 796 propensity score matched patients hospitalised for ischaemic LLA between 2010 and 2018 were analysed for cardiovascular comorbidities, treatment, and for subsequent cardiovascular and limb events, with a distinct focus on sex. Matching was performed, to ensure that the rate of major amputations and the age distribution were equal in both groups (in both sexes). An observation period of two years before index and a follow up (FU) period until 2019 were included.

RESULTS

Before index amputation, 68% of patients had received any kind of peripheral revascularisation. The use of statins (37.0% vs. 42.6%) and antithrombotic substances (54.9% vs. 61.8%) was lower in women than in men (p < .001). During two year FU, cardiovascular and limb events occurred among women and men as follows: limb re-amputation (26.7% vs. 31.2%), myocardial infarction (10.9% vs. 14.5%), stroke (20.8% vs. 20.7%), and death from any cause (51.0% vs. 53.3%, p < .001 except for stroke). After adjustment for cardiovascular comorbidities and vascular procedures, female sex was associated with a higher probability of death (HR 1.04, 95% CI 1.04 - 1.04).

CONCLUSION

Patients undergoing ischaemic LLA still have a poor prognosis marked by high rates of recurrent cardiovascular and limb events resulting in a > 50% mortality rate within two years. The continuous lack of guideline recommended therapies, particularly in women, may be associated with the persisting poor outcome, necessitating urgent further investigation.

Amputation-free survival in the long-term follow-up and gender-related characteristics in patients revascularized for critical limb ischemia

OBJECTIVE

Patients with Critical Limb Ischemia (CLI) present a high risk of cardiovascular events and death. Revascularization is the cornerstone of therapy to relieve ischemic pain and prevent limb loss. Literature data suggest that women tend to present with worse outcomes after revascularization. The aim of the present study is to determine amputation-free survival in a long-term follow-up in women and men following endovascular revascularization procedure for CLI.

METHODS

From November 2013 to December 2020, 357 consecutive patients were retrospectively included. Clinical and biological parameters were recorded at baseline before endovascular revascularization. During follow-up until February 2023, overall survival and amputation-free survival (freedom from major amputation) were analysed using the Kaplan-Meier method. Univariate and multivariate analyses were performed to study the parameters associated with amputation-free survival. A P<0.05 was considered as statistically significant.

RESULTS

A total of 357 consecutive patients were included, 189 men and 168 women with CLI, with a mean age of 78.6±12 years. Treated hypertension (79%), diabetes mellitus (48%), coronary artery disease (39%) and protein malnutrition (61%) were the most prevalent comorbidities. Women were older than men with a mean age of 82.4±11.4 years (versus 75.4±11 years in men) and presented more frequently with protein malnutrition (70% of women). Prevalence of diabetes, tobacco use and history of coronary heart disease were significantly higher in men. During the 10-year follow-up period, 241 patients had died (68%) and 38 (11%) underwent major amputation, of whom 22 patients were still alive on February 2023. Median survival was 35.5 months [IQR: 29.5; 43] in the overall population, 38.5 [32; 50.4] months in women and 33.5 months [24.7; 43.5] in men. No gender-related differences were noted according to peri-procedural complications, survival probability and amputation-free survival. In multivariate analysis for amputation-free survival, age, previous coronary heart disease, C-reactive protein level, left ventricular ejection fraction (LVEF)<60% and albumin level<35g/L were correlated with poor outcome. In particular, protein malnutrition, as a treatable risk factor, appears significantly correlated with poor outcome in both men and women (HR=2.50 [1.16;5.38], P=0.0196 in men; HR=1.77 [1.00;3.13], P=0.049 in women).

CONCLUSION

The present results highlight that mortality in patients after endovascular revascularization remains high with a mortality rate of 28% at 1 year, 40% at 2 years and 51% at 3 years. Women represented a distinct population, almost 10-year older than their male counterparts, with more prevalent protein malnutrition. However, no gender-related difference was noted according to amputation-free survival on the long-term follow-up. Associated risk factors are mainly age, a history of coronary heart disease, pre-procedural inflammatory syndrome and protein malnutrition. Correction of malnutrition could have the potential to improve functional and general long-term prognosis in patients with CLI together with optimal medical and interventional management.

Sex-Related Differences and Factors Associated with Peri-Procedural and 1 Year Mortality in Chronic Limb-Threatening Ischemia Patients from the CLIMATE Italian Registry

BACKGROUND

Identifying sex-related differences/variables associated with 30 day/1 year mortality in patients with chronic limb-threatening ischemia (CLTI).

METHODS

Multicenter/retrospective/observational study. A database was sent to all the Italian vascular surgeries to collect all the patients operated on for CLTI in 2019. Acute lower-limb ischemia and neuropathic-diabetic foot are not included.

FOLLOW-UP

One year. Data on demographics/comorbidities, treatments/outcomes, and 30 day/1 year mortality were investigated.

RESULTS

Information on 2399 cases (69.8% men) from 36/143 (25.2%) centers. Median (IQR) age: 73 (66-80) and 79 (71-85) years for men/women, respectively (p < 0.0001). Women were more likely to be over 75 (63.2% vs. 40.1%, p = 0.0001). More men smokers (73.7% vs. 42.2%, p < 0.0001), are on hemodialysis (10.1% vs. 6.7%, p = 0.006), affected by diabetes (61.9% vs. 52.8%, p < 0.0001), dyslipidemia (69.3% vs. 61.3%, p < 0.0001), hypertension (91.8% vs. 88.5%, p = 0.011), coronaropathy (43.9% vs. 29.4%, p < 0.0001), bronchopneumopathy (37.1% vs. 25.6%, p < 0.0001), underwent more open/hybrid surgeries (37.9% vs. 28.8%, p < 0.0001), and minor amputations (22% vs. 13.7%, p < 0.0001). More women underwent endovascular revascularizations (61.6% vs. 55.2%, p = 0.004), major amputations (9.6% vs. 6.9%, p = 0.024), and obtained limb-salvage if with limited gangrene (50.8% vs. 44.9%, p = 0.017). Age > 75 (HR = 3.63, p = 0.003) is associated with 30 day mortality. Age > 75 (HR = 2.14, p < 0.0001), nephropathy (HR = 1.54, p < 0.0001), coronaropathy (HR = 1.26, p = 0.036), and infection/necrosis of the foot (dry, HR = 1.42, p = 0.040; wet, HR = 2.04, p < 0.0001) are associated with 1 year mortality. No sex-linked difference in mortality statistics.

CONCLUSION

Women exhibit fewer comorbidities but are struck by CLTI when over 75, a factor associated with short- and mid-term mortality, explaining why mortality does not statistically differ between the sexes.

End-stage renal disease, calcification patterns and clinical outcomes after TAVI

BACKGROUND

Patients with chronic hemodialysis due to end-stage renal disease (ESRD) or severely impaired kidney function (CKD) constitute a relevant share of patients undergoing trans-catheter aortic valve implantation (TAVI). However, data on specific challenges and outcomes remain limited.

AIM

We aimed to characterize this patient population, evaluate clinical results and assess the significance of calcification patterns.

METHODS

This retrospective single-center analysis evaluated 2,712 TAVI procedures (2012-2019) according to baseline renal function: GFR < 30 ml/min/1.73m2 (CKD; n = 210), chronic hemodialysis (ESRD; n = 119) and control (CTRL; n = 2383). Valvular and vascular calcification patterns were assessed from contrast-enhanced multi-detector computed tomography. Outcomes were evaluated in accordance with the VARC-2 definitions.

RESULTS

Operative risk was higher in ESRD and CKD vs. CTRL (STS-score 8.4% and 7.6% vs. 3.9%, p < 0.001) and patients with ESRD had more severe vascular calcifications (49.1% vs. 33.9% and 29.0%, p < 0.01). Immediate procedural results were similar but non-procedure-related major/life-threatening bleeding was higher in ESRD and CKD (5.0% and 5.3% vs. 1.6%, p < 0.01). 3-year survival was impaired in patients with ESRD and CKD (33.3% and 35.3% vs. 65.4%, p < 0.001). Multivariable analysis identified ESRD (HR 1.60), CKD (HR 1.79) and vascular calcifications (HR 1.29) as predictors for 3-year and vascular calcifications (HR 1.51) for 30-day mortality.

CONCLUSION

Patients with ESRD and CKD constitute a vulnerable patient group with extensive vascular calcifications. Immediate procedural results were largely unaffected by renal impairment, yielding TAVI a particularly valuable treatment option in these high-risk operative patients. Mid-term survival was determined by underlying renal disease, cardiovascular comorbidities, and vascular calcifications as a novel risk marker.

Medial Arterial Calcification: A Significant and Independent Contributor of Peripheral Artery Disease

Over 200 million individuals worldwide are estimated to have peripheral artery disease (PAD). Although the term peripheral can refer to any outer branch of the vasculature, the focus of this review is on lower-extremity arteries. The initial sequelae of PAD often include movement-induced cramping pain in the hips and legs or loss of hair and thinning of the skin on the lower limbs. PAD progresses, sometimes rapidly, to cause nonhealing ulcers and critical limb ischemia which adversely affects mobility and muscle tone; acute limb ischemia is a medical emergency. PAD causes great pain and a high risk of amputation and ultimately puts patients at significant risk for major adverse cardiovascular events. The negative impact on patients' quality of life, as well as the medical costs incurred, are huge. Atherosclerotic plaques are one cause of PAD; however, emerging clinical data now shows that nonatherosclerotic medial arterial calcification (MAC) is an equal and distinct contributor. This ATVB In Focus article will present the recent clinical findings on the prevalence and impact of MAC in PAD, discuss the known pathways that contribute specifically to MAC in the lower extremity, and highlight gaps in knowledge and tools that limit our understanding of MAC pathogenesis.

Sex Differences in Peripheral Artery Disease

Peripheral artery disease (PAD) is a prevalent condition that confers substantial morbidity and mortality and remains underdiagnosed as well as undertreated in the overall population. Although PAD prevalence is similar or higher in women compared with men, associations of traditional and nontraditional risk factors with PAD and clinical manifestations of PAD differ by sex and may contribute to delayed or lack of diagnosis in women. Such sex-based differences in the manifestation of PAD may arise from sexual dimorphism in the vascular substrate in health as well as sex variation in the responses to vascular stressors. Despite the availability of proven therapies for improving symptoms and reducing risk of ischemic cardiovascular and limb events among patients with diagnosed PAD, important sex differences in treatment and outcomes have been observed. We provide an overview of current knowledge regarding sex differences in the epidemiology, pathophysiology, clinical presentation, and management of PAD.

OUP accepted manuscript

Aims

The prevalence of chronic limb-threatening ischaemia (CLTI) is increasing and available data often derive from cohorts with various selection criteria. In the present study, we included CLTI patients and studied sex-related differences in their risk profile, vascular procedures, and long-term outcome.

Methods and results

We analysed 199 953 unselected patients of the largest public health insurance in Germany (AOK: Local healthcare funds), hospitalized between 2010 and 2017 for a main diagnosis of CLTI. A baseline period of 2 years before index hospitalization to assess comorbidities and previous procedures, and a follow-up period until 2018 were included. Female CLTI patients were older (median 81.4 vs. 73.8 years in males; P < 0.001) and more often diagnosed with hypertension, atrial fibrillation, chronic heart failure, and chronic kidney disease. Male patients suffered more frequently from diabetes mellitus, dyslipidaemia, smoking, cerebrovascular disease, and chronic coronary syndrome (all P < 0.001). Within hospitalized CLTI patients, females represent the minority (43% vs. 57%; P < 0.001) and during index hospitalization, women underwent less frequently diagnostic angiographies (67 vs. 70%) and revascularization procedures (61 vs. 65%; both P < 0.001). Moreover, women received less frequently guideline-recommended drugs like statins (35 vs. 43%) and antithrombotic therapy (48 vs. 53%; both P < 0.001) at baseline. Interestingly, after including age and comorbidities in a Cox regression analysis, female sex was associated with increased overall-survival (OS) [hazard ratio (HR) 0.95; 95% confidence interval (CI) 0.94–0.96] and amputation-free survival (AFS) (HR 0.84; 95% CI 0.83–0.85; both P < 0.001).

Conclusion

Female patients with CLTI were older, underwent less often vascular procedures, and received less frequently guideline-recommended medication. Nevertheless, female sex was independently associated with better OS and AFS during follow-up.

Medical Management of Peripheral Arterial Disease: Deciphering the Intricacies of Therapeutic Options

Due to the pathophysiology of atherosclerosis, the management for coronary artery disease and peripheral arterial disease (PAD) were considered homogenous, with therapies focused on the use of lipid-lowering medications, antiplatelet therapy, glucose control, and blood pressure management. However, more recently, studies have supported the use of tailored therapeutics and medical targets for patients with PAD that sometimes differ from those for coronary artery disease. Moreover, we are now witnessing large randomized PAD-specific trials that have altered therapeutic regimens and targets. Given these updates, dissemination of knowledge is lacking, as evidenced by discordant guideline recommendations. This comprehensive review provides an overview of contemporary therapeutic options for secondary prevention for patients with PAD.

Racial differences in the limb skeletal muscle transcriptional programs of patients with critical limb ischemia

Critical limb ischemia (CLI) is the most severe manifestation of peripheral artery disease (PAD) and is characterized by high rates of morbidity and mortality. As with most severe cardiovascular disease manifestations, Black individuals disproportionately present with CLI. Accordingly, there remains a clear need to better understand the reasons for this discrepancy and to facilitate personalized therapeutic options specific for this population. Gastrocnemius muscle was obtained from White and Black healthy adult volunteers and patients with CLI for whole transcriptome shotgun sequencing (WTSS) and enrichment analysis was performed to identify alterations in specific Reactome pathways. When compared to their race-matched healthy controls, both White and Black patients with CLI demonstrated similar reductions in nuclear and mitochondrial encoded genes and mitochondrial oxygen consumption across multiple substrates, indicating a common bioenergetic paradigm associated with amputation outcomes regardless of race. Direct comparisons between tissues of White and Black patients with CLI revealed hemostasis, extracellular matrix organization, platelet regulation, and vascular wall interactions to be uniquely altered in limb muscles of Black individuals. Among traditional vascular growth factor signaling targets, WTSS revealed only Tie1 to be significantly altered from White levels in Black limb muscle tissues. Quantitative reverse transcription polymerase chain reaction validation of select identified targets verified WTSS directional changes and supports reductions in MMP9 and increases in NUDT4P1 and GRIK2 as unique to limb muscles of Black patients with CLI. This represents a critical first step in better understanding the transcriptional program similarities and differences between Black and White patients in the setting of amputations related to CLI and provides a promising start for therapeutic development in this population.

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.