Race as a predictor of morbidity, mortality, and neurologic events after carotid endarterectomy

Non-White Patients Have a Higher Risk of Stroke Following Transcarotid Artery Revascularization

INTRODUCTION

Carotid artery revascularization has traditionally been performed by either a carotid endarterectomy or carotid artery stent. Large data analysis has suggested there are differences in perioperative outcomes with regards to race, with non-White patients (NWP) having worse outcomes of stroke, restenosis and return to the operating room (RTOR). The introduction of transcarotid artery revascularization (TCAR) has started to shift the paradigm of carotid disease treatment. However, to date, there have been no studies assessing the difference in postoperative outcomes after TCAR between racial groups.

METHODS

All patients from 2016 to 2021 in the Vascular Quality Initiative who underwent TCAR were included in our analysis. Patients were split into two groups based on race: individuals who identified as White and a second group that comprised all other races. Demographic and clinical variables were compared using Student's t-Test and chi-square test of independence. Logistic regression analysis was performed to determine the impact of race on perioperative outcomes of stroke, myocardial infarction (MI), death, restenosis, RTOR, and transient ischemic attack (TIA).

RESULTS

The cohort consisted of 22,609 patients: 20,424 (90.3%) White patients and 2185 (9.7%) NWP. After adjusting for sex, diabetes, hypertension, coronary artery disease, history of prior stroke or TIA, symptomatic status, and high-risk criteria at time of TCAR, there was a significant difference in postoperative stroke, with 63% increased risk in NWP (odds ratio = 1.63, 95% confidence interval: 1.11-2.40, P = 0.014). However, we found no significant difference in the odds of MI, death, postoperative TIA, restenosis, or RTOR when comparing NWP to White patients.

CONCLUSIONS

This study demonstrates that NWP have increased risk of stroke but similar outcomes of death, MI, RTOR and restenosis following TCAR. Future studies are needed to elucidate and address the underlying causes of racial disparity in carotid revascularization.

Systematic review and meta-analysis to assess the racial disparities in the outcomes of carotid endarterectomy in the United States

OBJECTIVE

Race-based disparities in health care have been related to a myriad of prevailing factors among minorities in the United States. This study aims to study the race-based differences in the outcomes of carotid endarterectomy (CEA).

METHODS

The PROSPERO database registered the review protocol (CRD42023428253). A systematic English literature review was performed using literature databases PubMed and Scopus from inception till June 2023. The review was designed on the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines and included studies reporting mortality, stroke, or composite outcome of mortality and stroke after CEA for carotid artery disease, regardless of any degree of stenosis including both symptomatic and asymptomatic patients. The risk of bias was evaluated utilizing the Risk of Bias in Non-randomized Studies - of Interventions (ROBINS-I) tool. A pooled odds ratio (OR) for the overall mortality was computed, and a P value of < .05 was designated as statistically significant. Interstudy heterogeneity was evaluated by Q-metric and quantified using Higgins I2 statistics.

RESULTS

Twelve studies were identified which included a total of 574,055 patients who underwent CEA from 1998 to 2022. Eleven of 12 studies reported 30-day mortality as an outcome for patients undergoing CEA in which 524,708 patients (92.5%) were White and 42,797 (7.5%) were non-White. The overall pooled OR indicated a statistical significance in 30-day mortality between White and non-White patients undergoing CEA (OR, 1.73; 95% confidence interval [CI], 1.37-2.18; P = .011) with substantial heterogeneity (I2 = 56.3%). Eleven of 12 studies reported stroke as an outcome for patients undergoing CEA in which 524,708 patients (92.5%) were White and 42,801 (7.5%) were non-White. The overall pooled OR indicated no statistical significance in stroke between White and non-White patients undergoing CEA (OR, 1.46; 95% CI, 1.28-1.65; P = .111) with moderate heterogeneity (I2 = 35.9%). Five of 12 studies reported composite mortality or stroke as an outcome for patients undergoing CEA. The overall pooled OR indicated no statistical significance in composite mortality or stroke between White and non-White patients undergoing CEA (OR, 1.40; 95% CI, 1.24-1.59; P = .467) with no heterogeneity (I2 = 0.0%).

CONCLUSIONS

Non-White patients have a relatively higher risk of mortality; however, no significant difference was observed between the racial groups in terms of stroke or a composite outcome of mortality or stroke. The odds of mortality in non-White patients have been persistent throughout recent studies.

Socioeconomic status fails to account for worse outcomes in non-Hispanic black patients undergoing carotid revascularization

OBJECTIVE

Previous studies have reported an association of Black race with worse carotid revascularization outcomes, but rarely include socioeconomic status as a confounding covariate. We aimed to assess the association of race and ethnicity with in-hospital and long-term outcomes following carotid revascularization before and after accounting for socioeconomic status.

METHODS

We identified non-Hispanic Black and non-Hispanic white patients who underwent carotid endarterectomy, transfemoral carotid stenting, or transcarotid artery revascularization between 2003 and 2022 in the Vascular Quality Initiative. Primary outcomes were in-hospital stroke/death and long-term stroke/death. Multivariable logistic regression and Cox proportional hazards models were used to assess the association of race with perioperative and long-term outcomes after adjusting for baseline characteristics using a sequential model approach without and with consideration of Area Deprivation Index (ADI), a validated composite marker of socioeconomic status.

RESULTS

Of 201,395 patients, 5.1% (n = 10,195) were non-Hispanic Black, and 94.9% (n = 191,200) were non-Hispanic white. Mean follow-up time was 3.4±0.01 years. A disproportionately high percentage of Black patients were living in more socioeconomically deprived neighborhoods relative to their white counterparts (67.5% vs 54.2%; P < .001). After adjusting for demographic, comorbidity, and disease characteristics, Black race was associated with greater odds of in-hospital (adjusted odds ratio [aOR], 1.24; 95% confidence interval [CI], 1.10-1.40) and long-term stroke/death (adjusted hazard ratio [aHR], 1.13; 95% CI, 1.04-1.23). These associations did not substantially change after additionally adjusting for ADI; Black race was persistently associated with greater odds of in-hospital (aOR, 1.23; 95% CI, 1.09-1.39) and long-term stroke/death (aHR, 1.12; 95% CI, 1.03-1.21). Patients living in the most deprived neighborhoods were at greater risk of long-term stroke/death compared with patients living in the least deprived neighborhoods (aHR, 1.19; 95% CI, 1.05-1.35).

CONCLUSIONS

Non-Hispanic Black race is associated with worse in-hospital and long-term outcomes following carotid revascularization despite accounting for neighborhood socioeconomic deprivation. There appears to be unrecognized gaps in care that prevent Black patients from experiencing equitable outcomes following carotid artery revascularization.

Bias in artificial intelligence in vascular surgery

Application of artificial intelligence (AI) has revolutionized the utilization of big data, especially in patient care. The potential of deep learning models to learn without a priori assumption, or without prior learning, to connect seemingly unrelated information mixes excitement alongside hesitation to fully understand AI's limitations. Bias, ranging from data collection and input to algorithm development to finally human review of algorithm output affects AI's application to clinical patient presents unique challenges that differ significantly from biases in traditional analyses. Algorithm fairness, a new field of research within AI, aims to mitigate bias by evaluating the data at the preprocessing stage, optimizing during algorithm development, and evaluating algorithm output at the postprocessing stage. As the field continues to develop, being cognizant of the inherent biases and limitations related to black box decision making, biased data sets agnostic to patient-level disparities, wide variation of present methodologies, and lack of common reporting standards will require ongoing research to provide transparency to AI and its applications.

Racial and ethnic differences in presentation severity and postoperative outcomes in vascular surgery

BACKGROUND

We assessed the effect of race and ethnicity on presentation severity and postoperative outcomes in those with abdominal aortic aneurysms (AAAs), carotid artery stenosis (CAS), peripheral arterial disease (PAD), and type B aortic dissection (TBAD).

METHODS

MEDLINE, Embase, and Cochrane Central Register of Controlled Trials from inception until December 2020. Two reviewers independently selected randomized controlled trials and observational studies reporting race and/or ethnicity and presentation severity and/or postoperative outcomes for adult patients who had undergone major vascular procedures. They independently extracted the study data and assessed the risk of bias using the Newcastle-Ottawa scale. The meta-analysis used random effects models to derive the odds ratios (ORs) and risk ratios (RRs) and their corresponding 95% confidence intervals (CIs). The primary outcome was presentation severity stratified by the proportion of patients with advanced disease, including ruptured vs nonruptured AAA, symptomatic vs asymptomatic CAS, chronic limb-threatening ischemia vs claudication, and complicated vs uncomplicated TBAD. The secondary outcomes included postoperative all-cause mortality and disease-specific outcomes.

RESULTS

A total of 81 studies met the inclusion criteria. Black (OR, 4.18; 95% CI, 1.31-13.26), Hispanic (OR, 2.01; 95% CI, 1.85-2.19), and Indigenous (OR, 1.97; 95% CI, 1.39-2.80) patients were more likely to present with ruptured AAAs than were White patients. Black and Hispanic patients had had higher symptomatic CAS (Black: OR, 1.20; 95% CI, 1.04-1.38; Hispanic: OR, 1.32; 95% CI, 1.20-1.45) and chronic limb-threatening ischemia (Black: OR, 1.67; 95% CI, 1.14-2.43; Hispanic: OR, 1.73; 95% CI 1.13-2.65) presentation rates. No study had evaluated the effect of race or ethnicity on complicated TBAD. All-cause mortality was higher for Black (RR, 1.23; 95% CI, 1.01-1.51), Hispanic (RR, 1.90; 95% CI, 1.57-2.31), and Indigenous (RR, 1.24; 95% CI, 1.12-1.37) patients after AAA repair. Postoperatively, Black (RR, 1.54; 95% CI, 1.19-2.00) and Hispanic (RR, 1.54; 95% CI, 1.31-1.81) patients were associated with stroke/transient ischemic attack after carotid revascularization and lower extremity amputation (RR, 1.90; 95% CI, 1.76-2.06; and RR, 1.69; 95% CI, 1.48-1.94, respectively).

CONCLUSIONS

Certain visible minorities were associated with higher morbidity and mortality across various vascular surgery presentations. Further research to understand the underpinnings is required.

Risk Factors for Surgical Site Infections After Lower Extremity Open Revascularization

BACKGROUND

Surgical site infection (SSI) is a serious complication of lower extremity open revascularization and is associated with increased morbidity, increased healthcare costs, and decreased postoperative quality of life. The objective of this study was to determine factors associated with an increased risk of developing postoperative SSI in patients undergoing lower extremity revascularization. Associations between SSI and postoperative complications were also identified.

METHODS

Patients who underwent lower extremity open revascularization from 2014-2017 were identified using the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP). A multivariate logistic regression analysis was used to determine risk factors associated with SSIs within 30 days of the operation and postoperative complications. Odds ratios (ORs) were adjusted for demographics, preoperative comorbidities, procedure type, and intraoperative variables.

RESULTS

Ten thousand nine hundred ten patients who underwent lower extremity open revascularization were identified, with a mean age of 67.24 years and of whom 7,318 (67%) were male. Of the 10,910 patients, 922 (8.45%) had an SSI within 30 days of the operation. Risk factors associated with developing SSI included body mass index 25-29.9 (OR, 1.34; 95% confidence interval [CI], 1.08-1.67), body mass index ≥ 30 (OR, 2.12; 95% CI, 1.71-2.62), history of severe chronic obstructive pulmonary disease (OR, 1.47; 95% CI, 1.18-1.84), preprocedural beta-blocker use (OR, 1.25; CI 95%, 1.05-1.49), procedure time > 214 minutes (OR, 1.44; 95% CI, 1.22-1.70), and creatinine > 1.2 (OR 1.03; 95% CI, 0.87-1.21). One factor associated with a decreased risk of developing SSI was male gender (OR, 0.71; 95% CI, 0.60-0.84). Patients who developed an SSI were more likely to have adverse outcomes such as myocardial infarction/stroke, major amputation, bleeding requiring transfusion or secondary procedure, or require a reintervention in the treated segment.

CONCLUSIONS

There are various patient-related and operative factors that increase the likelihood of developing an SSI after lower extremity open revascularization. These findings indicate that addressing modifiable perioperative SSI risk factors may be beneficial in decreasing rates of SSI and improving postoperative outcomes.

Association between Race and Perioperative Outcomes after Carotid Endarterectomy for Asymptomatic Carotid Artery Stenosis in NSQIP

BACKGROUND

Previous studies have documented that Black patients have worse outcomes after lower extremity revascularization procedures compared with White patients. However, the association of race on carotid endarterectomy (CEA) outcomes is not well described. The aim of this study was to compare perioperative outcomes of CEA for Black vs White patients with asymptomatic carotid artery stenosis.

STUDY DESIGN

All patients who underwent CEA for asymptomatic carotid stenosis in the ACS-NSQIP targeted vascular database (2011-2019) were included. Perioperative (30-day) outcomes were compared for Black vs White patients using multivariable logistic regression adjusting for age/sex, comorbidities, and disease characteristics.

RESULTS

Of 16,764 asymptomatic CEA patients, 95.2% (N = 15,960) were White and 4.8% (N = 804) were Black. Black patients were slightly younger (mean age 71.4 ± 0.1 vs 69.9 ± 0.3 years, P < 0.001) and more frequently had high-grade carotid artery stenosis compared to White patients (79.5% vs 74.0%, p = 0.001). Comorbidities including hypertension, diabetes, kidney disease, congestive heart failure, and coronary artery disease were all more prevalent among Black patients (p ≤ 0.01). Crude perioperative stroke (2.4% vs 1.3%, p = 0.007) and stroke/death (2.6% vs 1.4%, p = 0.003) were higher for Black patients, but myocardial infarction (1.7% vs 1.5%, p = 0.67) and death (0.4% vs 0.2%, p = 0.12) were similar. After adjusting for baseline differences between groups, the risk of perioperative stroke (odds ratio 1.66, 95% CI 1.01 to 2.73) and stroke/death (odds ratio 1.75, 95% CI 1.10 to 2.81) remained significantly higher for Black patients compared with White patients.

CONCLUSIONS

Black patients undergoing CEA for asymptomatic carotid artery stenosis had more severe stenosis, more comorbidities, and worse perioperative outcomes compared to White patients. Overall, our data suggest substantial differences in the treatment and outcomes of asymptomatic carotid artery stenosis based on race.

Disparities in the Surgical Treatment of Cerebrovascular Pathologies: A Contemporary Systematic Review

INTRODUCTION

This systematic review analyzes contemporary literature on racial/ethnic, insurance, and socioeconomic disparities within cerebrovascular surgery in the United States to determine areas for improvement.

METHODS

We conducted an electronic database search of literature published between January 1990 and July 2020 using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines for studies analyzing a racial/ethnic, insurance, or socioeconomic disparity within adult cerebrovascular surgery.

RESULTS

Of 2873 articles screened for eligibility by title and abstract, 970 underwent full-text independent review by 3 authors. Twenty-seven additional articles were identified through references to generate a final list of 47 included studies for analysis. Forty-six were retrospective reviews and 1 was a prospective observational cohort study, thereby comprising Levels III and IV of evidence. Studies investigated carotid artery stenting (11/47, 23%), carotid endarterectomy (22/47, 46.8%), mechanical thrombectomy (8/47, 17%), and endovascular aneurysm coiling or surgical aneurysm clipping (20/47, 42.6%). Minority and underinsured patients were less likely to receive surgical treatment. Non-White patients were more likely to experience a postoperative complication, although this significance was lost in some studies using multivariate analyses to account for complication risk factors. White and privately insured patients generally experienced shorter length of hospital stay, had lower rates of in-hospital mortality, and underwent routine discharge. Twenty-five papers (53%) reported no disparities within at least one examined metric.

CONCLUSIONS

This comprehensive contemporary systematic review demonstrates the existence of disparity gaps within the field of adult cerebrovascular surgery. It highlights the importance of continued investigation into sources of disparity and efforts to promote equity within the field.

Gender, racial and ethnic disparities in index hospitalization operations for symptomatic carotid stenosis in Texas hospitals

BACKGROUND

Recent literature and societal recommendations support early revascularization of symptomatic carotid patients over the traditional six-week period. Nonetheless, the timing of these interventions can vary widely among populations. The goal of this study is to identify any factors influencing carotid revascularization during the index hospitalization for patients with symptomatic disease.

METHODS

The Texas Department of State Health Services database was queried to identify all patients > 45 years old admitted to nonfederal Texas Hospitals between 2009 to 2013 with an admission diagnosis of carotid artery stenosis and either transient ischemic attack (TIA), cerebrovascular accident (CVA), or amaurosis fugax. Diagnoses codes and demographic data were also used to adjust for clinical, social, and demographic factors (including area of residence and treatment). Descriptive statistics and multivariable logistic regression were used to identify significant factors for index admission revascularization.

RESULTS

A total of 29,046 symptomatic patients were identified among the 153,484 patients who had an eligible admission diagnosis. This included 16,244 (55.9%) males and 12,802 (44.1%) females. Only 4,594 (15.8%) patients were revascularized during the index hospitalization. The majority of these patients presented with amaurosis (OR 5.58; 95% CI 4.84-6.44) instead of CVAs (OR 0.48; 95% CI 0.45-0.51) or TIAs . Adjusting for hospital volume, insurance coverage, residence, and other clinical factors, rates of index admission carotid intervention remained significantly lower for women (OR 0.85; 95% CI 0.79-0.91), persons categorized as black (OR 0.60; 95% CI 0.53-0.69), and persons categorized as Hispanic (OR 0.77; 95% CI 0.70-0.86).

CONCLUSIONS

Gender, race and ethnicity appear to correlate with rates of carotid intervention at index hospitalization despite thorough risk adjustment for clinical, social and demographic factors. Efforts should be directed towards reducing these disparities.

Differences in Perioperative Outcomes after Carotid Revascularization between White and Non-white Patients

BACKGROUND

Racial disparities in carotid endarterectomy (CEA) and carotid artery stenting (CAS) continue to persist. We aimed to provide a large-scale analysis of racial disparities in perioperative outcomes of carotid revascularization in a nationally representative cohort of patients, with sub-analyses stratifying by procedure type and symptomatic status.

METHODS

We studied all patients undergoing carotid revascularization between 2011 and 2018 in the American College of Surgeons (ACS) National Surgical Quality Improvement Program (NSQIP) Database. Univariate methods were used to compare patients' demographic and medical characteristics. Multivariable logistic regression analysis was used to compare adjusted perioperative outcomes between white patients (WP) and non-white patients (NWP). Sub-analysis was performed stratifying by method of revascularization and symptomatic status.

RESULTS

A total of 31,356 carotid revascularizations were performed in 26,550 (84.7%) white patients and 4,806 (15.3%) non-white patients. On adjusted analysis, NWP had increased odds of stroke (OR:1.2, 95%CI:1.1-1.5, P = 0.0496), unplanned return to the OR (OR:1.4, 95%CI:1.1-1.6, P < 0.001) and restenosis (OR:2.6, 95%CI:1.7-3.9, P < 0.001). On sub-analysis, NWP undergoing CAS had increased odds of stroke/death (OR:2.2, 95%CI:1.1-4.3, P = 0.025), stroke (OR:2.9, 95%CI:1.3-6.0, P = 0.007), and stroke/TIA (OR:2.1, 95%CI:1.0-4.2, P = 0.025). NWP undergoing CEA had increased odds of unplanned return to the OR (OR:1.4, 95%CI:1.2-1.6, P < 0.001) and restenosis (OR:2.7, 95%CI:1.7-4.0, P < 0.001).

CONCLUSION

NWP had higher rates of 30-day stroke, driven primarily by higher rates of perioperative stroke/death in NWP undergoing CAS. NWP undergoing CEA did not have higher rates of stroke/death after adjusted analysis, although they had higher rates of unplanned return to OR and restenosis. Upon stratification for symptomatic status, the stroke/death rate between NWP and WP was shown to be non-significant.

Management of patients with asymptomatic carotid stenosis may need to be individualized: a multidisciplinary call for action. Republication of J Stroke 2021;23:202-212

The optimal management of patients with asymptomatic carotid stenosis (ACS) is the subject of extensive debate. According to the 2017 European Society for Vascular Surgery guidelines, carotid endarterectomy should (Class IIa; Level of Evidence: B) or carotid artery stenting may be considered (Class IIb; Level of Evidence: B) in the presence of one or more clinical/imaging characteristics that may be associated with an increased risk of late ipsilateral stroke (e.g. silent embolic infarcts on brain computed tomography/magnetic resonance imaging, progression in the severity of ACS, a history of contralateral transient ischemic attack/stroke, microemboli detection on transcranial Doppler, etc.), provided documented perioperative stroke/death rates are <3% and the patient's life expectancy is >5 years. Besides these clinical/imaging characteristics, there are additional individual, ethnic/racial or social factors that should probably be evaluated in the decision process regarding the optimal management of these patients, such as individual patient needs/patient choice, patient compliance with best medical treatment, patient sex, culture, race/ethnicity, age and comorbidities, as well as improvements in imaging/operative techniques/outcomes. The present multispecialty position paper will present the rationale why the management of patients with ACS may need to be individualized.

Creatine kinase and bleeding in patients with acute coronary syndromes

BACKGROUND

The association between elevated creatine kinase (CK) and bleeding in patients with acute coronary syndrome (ACS) remains incompletely investigated. We undertook this study to assess whether there is an association between elevated CK activity and the risk for bleeding in contemporary patients with ACS.

MATERIALS AND METHODS

This post hoc analysis of a randomized trial included 3368 patients with ACS undergoing percutaneous coronary intervention. CK was measured serially in all patients until hospital discharge. The main outcome was 30-day incidence of major bleeding (type 3 to 5 bleeding according to the Bleeding Academic Research Consortium criteria).

RESULTS

Patients were categorized in groups according to the peak CK tertiles: 1st tertile (CK ≤259 U/L; n = 1127 patients), 2nd tertile (CK ≥260 to 990 U/L; n = 1119 patients), and 3rd tertile (CK ≥ 991 U/L; n = 1122 patients). Peak CK activity was higher in patients with bleeding than those without bleeding (771 [316-1845] U/L vs. 496 [190-1357] U/L; P <.001). Bleeding occurred in 26 patients (2.3%) with peak CK within 1st tertile, 39 patients (3.5%) with peak CK within 2nd tertile, and 54 patients (4.8%) with peak CK within 3rd tertile (univariable hazard ratio [HR]=1.39, 95% confidence interval [CI] 1.08 to 1.81, P =.012, per tertile increment in CK values). After adjustment, peak CK activity remained significantly associated with the 30-day bleeding (HR = 1.67 [1.16-2.41]; P =.006 per unit increment in logarithmic CK values). The C statistic of the multivariable model with CK activity was 0.807 [0.770-0.842].

CONCLUSIONS

In patients with ACS, peak CK activity was independently associated with increased 30-day incidence of bleeding.

Race Differences in High-Grade Carotid Artery Stenosis

Background and Purpose

Despite a higher incidence of stroke and a more adverse cardiovascular risk factor profile in Blacks and Hispanics compared with Whites, carotid artery revascularization is performed less frequently among these subpopulations. We assessed racial differences in high-grade (≥70% diameter-reducing) carotid stenosis.

Methods

Consecutive clients in a Nationwide Life Line for-Profit Service to screen for vascular disease, 2005 to 2019 were evaluated in a cross-sectional study. The prevalence of high-grade stenosis, defined by a carotid ultrasound peak systolic velocity of ≥230 cm/s, was assessed. Participants self-identified as White, Black, Hispanic, Asian, Native American, or other. Race/ethnic differences were assessed using Poisson regression. The number of individuals in the United States with high-grade stenosis was estimated by applying prevalence estimates to 2015 US Census population estimates.

Results

The prevalence of high-grade carotid stenosis was estimated in 6 130 481 individuals. The prevalence of high-grade stenosis was higher with increasing age in all race-sex strata. Generally, Blacks and Hispanics had a lower prevalence of high-grade stenosis compared with Whites, while Native Americans had a higher prevalence. For example, for men aged 55 to 65, the relative risk of stenosis compared with Whites was 0.40 (95% CI, 0.29–0.55) and 0.61 (95% CI, 0.46–0.81) for Blacks and Hispanics, respectively; and 1.53 (95% CI, 1.12–2.10) for Native Americans. When these prevalence estimates were applied to the Census estimates of the US population, an estimated 327 721 individuals have high-grade stenosis, of whom 7% are Black, 7% Hispanic, and 43% women.

Conclusions

Despite their having a more adverse cardiovascular risk profile, there was a lower prevalence of high-grade carotid artery stenosis for both the Black and Hispanic relative to the White clients. This lower prevalence of high-grade stenosis is a potential contributor to the lower use of carotid revascularization procedures in these minority populations.

Management of Patients with Asymptomatic Carotid Stenosis May Need to Be Individualized: A Multidisciplinary Call for Action

The optimal management of patients with asymptomatic carotid stenosis (ACS) is the subject of extensive debate. According to the 2017 European Society for Vascular Surgery guidelines, carotid endarterectomy should (Class IIa; Level of Evidence: B) or carotid artery stenting may be considered (Class IIb; Level of Evidence: B) in the presence of one or more clinical/imaging characteristics that may be associated with an increased risk of late ipsilateral stroke (e.g., silent embolic infarcts on brain computed tomography/magnetic resonance imaging, progression in the severity of ACS, a history of contralateral transient ischemic attack/stroke, microemboli detection on transcranial Doppler, etc.), provided documented perioperative stroke/death rates are <3% and the patient’s life expectancy is >5 years. Besides these clinical/imaging characteristics, there are additional individual, ethnic/racial or social factors that should probably be evaluated in the decision process regarding the optimal management of these patients, such as individual patient needs/patient choice, patient compliance with best medical treatment, patient sex, culture, race/ethnicity, age and comorbidities, as well as improvements in imaging/operative techniques/outcomes. The present multispecialty position paper will present the rationale why the management of patients with ACS may need to be individualized.

Socioeconomic Disparities in Carotid Revascularization Procedures

OBJECTIVES

Several studies have demonstrated healthcare disparities in postoperative outcomes after carotid endarterectomy and carotid artery stenting, including increased hospital mortality, postoperative stroke, and readmission rates. The objective of the present study was to examine the intersectionality between race/ethnicity, insurance status, and postoperative outcomes in carotid procedures.

DESIGN

Records of adults from 2007 to 2014 were retrospectively identified, and patients with appropriate International Classification of Diseases Ninth Revision Clinical Modification codes for carotid endarterectomy or carotid artery stenting were identified. Primary outcomes were unadjusted rates and adjusted odds ratios (aORs) of postoperative in-hospital mortality, stroke, combined stroke/mortality, and cardiovascular complications.

SETTING

Data were sourced from the State Inpatient Databases data from California, Florida, Kentucky, Maryland, and New York during the years 2007 to 2014.

PARTICIPANTS

Patients undergoing carotid revascularization procedures.

INTERVENTIONS

The effects of race and insurance status as independent variables and as effect modifiers on postoperative outcomes.

MEASUREMENTS AND MAIN RESULTS

Multivariable logistic regression models were used to examine the associations between race and/or insurance status with respect to study outcomes. Race, but not payer status, was significantly associated with adverse outcomes after carotid artery procedures, with blacks, Hispanics, and other non-Caucasian races demonstrating a significantly greater risk of postoperative stroke and mortality (aOR range 1.24-1.59). This relationship persisted even when stratified by procedure type (aOR range 1.25-1.56) and symptomatology (aOR range 1.51-1.63).

CONCLUSIONS

These results suggest that disparities in postoperative outcomes after carotid artery procedures are associated with race but not with primary insurance status. Multiple contributing factors exist, including racial inequities in prevalence of comorbidities, health literacy, and procedure type performed.

Race and sex-based disparities associated with carotid endarterectomy in the Atherosclerosis Risk in Communities (ARIC) study

BACKGROUND AND AIMS

The indications for carotid endarterectomy (CEA) are well established. The aim of the current study was to investigate sex and race-based disparities in the incidence of CEA after adjusting for carotid artery stenosis risk factors.

METHODS

We conducted a prospective cohort analysis of 14,492 black and white participants in the Atherosclerosis Risk in Communities (ARIC) study without prevalent stroke at baseline (1987-1989). We used Kaplan-Meier curves and Cox proportional hazards models adjusting for sociodemographic, cardiovascular, and disease severity risk factors to quantify the associations of sex and race with incident CEA.

RESULTS

CEA was performed in 330 of 14,492 ARIC participants during a median of 27 years of follow-up [incidence rate 1.00 (95% CI 0.90-1.12) per 1000 persons-years]. The crude incidence of CEA varied significantly by sex [female vs. male: HR 0.60 (95% CI 0.48-0.74)] and race [black vs. white: HR 0.65 (95% CI 0.49-0.86)]. Adjustment for sociodemographic and cardiovascular risk factors, carotid intima-media thickness, and symptomatic status attenuated the association of sex with CEA [females vs. males HR 0.96 (0.76-1.22)], but black participants had a lower risk of incident CEA after adjustment [HR 0.68 (95% CI 0.49-0.95)].

CONCLUSIONS

We found significant variation in the incidence of CEA procedures based on race that was independent of traditional risk factors and carotid IMT. Whether this disparity is a reflection of differences in disease presentation or access to care deserves investigation.

Risk Scoring Systems to Predict Long-Term Mortality After Carotid Endarterectomy in Asymptomatic Patients: A Systematic Review

The present review was conducted to describe current published risk scoring systems to predict late mortality after carotid endarterectomy (CEA). The aim of the study is to identify simple, clinical, and reproducible tools to predict life expectancy in patients with asymptomatic carotid artery stenosis candidates to CEA and therefore which patients may benefit from surgery, reaching the goal of life expectancy >3 to 5 years, recommended by guidelines. Advantages, disadvantages, feasibility, simplicity, and reproducibility of each selected score were analyzed. Rigorous statistical analysis and validation of the score are essential components to produce a calibrated and usable score. Future studies should address the impact of using these tools in CEA candidates for asymptomatic disease.

Creatine kinase, energy reserve, and hypertension: from bench to bedside

We hypothesized that human variation in the activity of the ATP regenerating enzyme creatine kinase (CK) activity affects hypertension and cardiovascular disease risk. CK is tightly bound close to ATP-utilizing enzymes including Ca2+-ATPase, myosin ATPase, and Na+/K+-ATPase, where it rapidly regenerates ATP from ADP, H+, and phosphocreatine. Thus, relatively high CK was thought to enhance ATP-demanding processes including resistance artery contractility and sodium retention, and reduce ADP-dependent functions. In a series of studies of our group and others, CK was linked to hypertension and bleeding risk. Plasma CK after rest, used as a surrogate measure for tissue CK, was associated with high blood pressure and failure of antihypertensive therapy in case-control and population studies. Importantly, high tissue CK preceded hypertension in animal models and in humans, and human vascular tissue CK gene expression was strongly associated with clinical blood pressure. In line with this, CK inhibition substantially reduced the contractility of human resistance arteries ex vivo. We also presented evidence that plasma CK reduced ADP-dependent platelet aggregation. In subsequent intervention studies, the oral competitive CK inhibitor beta-guanidinopropionic acid (GPA) reduced blood pressure in spontaneously hypertensive rats (SHRs), and a 1-week trial of sub-therapeutic dose GPA in healthy men was uneventful. Thus, based on theoretical concepts, evidence was gathered in laboratory, case-control, and population studies that high CK is associated with hypertension and with bleeding risk, potentially leading to a new mode of cardiovascular risk reduction with CK inhibition.

The impact of race on outcomes after carotid endarterectomy in the United States

OBJECTIVE

Black patients undergoing carotid endarterectomy (CEA) in the United States are more often symptomatic at presentation and have more comorbidities compared with white patients. However, the impact of race on outcomes after CEA is largely unknown.

METHODS

We identified CEA patients in the Vascular Quality Initiative registry (2012-2017) and compared them by race (black vs white). All other nonwhite races (891 [1.4%]) and Hispanics (2222 [3.4%]) were excluded. We used multilevel logistic regression to account for differences in demographics and comorbidities. We assessed long-term survival using multivariable Cox regression. The primary outcome was perioperative stroke/death, with long-term survival as a secondary outcome.

RESULTS

We included 57,622 CEA patients; 2909 (5.0%) were black, of whom 983 (34%) were symptomatic. Of the 54,713 white patients, 16,132 (30%) were symptomatic. Black patients, compared with white patients, had a higher vascular disease burden and were less likely to be operated on in a high-volume hospital or by a high-volume surgeon. In addition, black symptomatic patients, compared with white symptomatic patients, were more often operated on <2 weeks after the index neurologic symptom (47% vs 40%; P < .001). Perioperative stroke/death was comparable between black and white patients (symptomatic, 2.8% vs 2.2% [P = .2]; asymptomatic, 1.6% vs 1.3% [P = .2]), as was unadjusted survival at 3 years (93% vs 93%; P = .7). However, after adjustment, black patients did experience better long-term survival compared with white patients (hazard ratio, 0.8; 95% confidence interval, 0.7-0.9; P = .01). On multilevel logistic regression, race was not associated with perioperative stroke/death (odds ratio, 1.0; 95% confidence interval, 0.8-1.3; P = .98).

CONCLUSIONS

Despite the greater prevalence of vascular risk factors in black patients and racial inequalities in surgical treatment, rates of perioperative stroke/death and unadjusted survival were similar between white and black patients. Moreover, black patients experienced better adjusted long-term survival after CEA.

Black patients present with more severe vascular disease and a greater burden of risk factors than white patients at time of major vascular intervention

BACKGROUND

Although many studies have demonstrated racial disparities after major vascular surgery, few have identified the reasons for these disparities, and those that did often lacked clinical granularity. Therefore, our aim was to evaluate differences in initial vascular intervention between black and white patients.

METHODS

We identified black and white patients' initial carotid, abdominal aortic aneurysm (AAA), and infrainguinal peripheral artery disease (PAD) interventions in the Vascular Quality Initiative (VQI) registry from 2009 to 2014. We excluded nonblack or nonwhite patients as well as those with Hispanic ethnicity, asymptomatic PAD, or a history of prior ipsilateral interventions. We compared baseline characteristics and disease severity at time of intervention on a national and regional level.

RESULTS

We identified 76,372 patients (9% black), including 35,265 carotid (5% black), 17,346 AAA (5% black), and 23,761 PAD interventions (18% black). For all operations, black patients were younger, more likely female, and had more insulin-dependent diabetes, hypertension, congestive heart failure, renal dysfunction, and dialysis dependence. Black patients were less likely to be on a statin before AAA (62% vs 69%; P < .001) or PAD intervention (61% vs 67%; P < .001) and also less likely to be discharged on an antiplatelet and statin regimen after these procedures (AAA, 60% vs 64% [P = .01]; PAD, 64% vs 67% [P < .001]). Black patients presented with more severe disease, including higher proportions of symptomatic carotid disease (36% vs 31%; P < .001), symptomatic or ruptured AAA (27% vs 16%; P < .001), and chronic limb-threatening ischemia (73% vs 62%; P < .001). Black patients more often presented with concurrent iliac artery aneurysms at the time of AAA repair (elective open AAA repair, 46% vs 26% [P < .001]; elective endovascular aneurysm repair, 38% vs 23% [P < .001]).

CONCLUSIONS

Black patients present with more advanced disease at the time of initial major vascular operation. Efforts to control risk factors, identify and treat arterial disease in a timely fashion, and optimize medical management among black patients may provide opportunity to improve current disparities.

Carotid Endarterectomy and Carotid Artery Stenting in the US Medicare Population, 1999-2014

IMPORTANCE

Carotid endarterectomy and carotid artery stenting are the leading approaches to revascularization for carotid stenosis, yet contemporary data on trends in rates and outcomes are limited.

OBJECTIVE

To describe US national trends in performance and outcomes of carotid endarterectomy and stenting among Medicare beneficiaries from 1999 to 2014.

DESIGN, SETTING, AND PARTICIPANTS

Serial cross-sectional analysis of Medicare fee-for-service beneficiaries aged 65 years or older from 1999 to 2014 using the Medicare Inpatient and Denominator files. Spatial mixed models adjusted for age, sex, and race were fit to calculate county-specific risk-standardized revascularization rates. Mixed models were fit to assess trends in outcomes after adjustment for demographics, comorbidities, and symptomatic status.

EXPOSURES

Carotid endarterectomy and carotid artery stenting.

MAIN OUTCOMES AND MEASURES

Revascularization rates per 100 000 beneficiary-years of fee-for-service enrollment, in-hospital mortality, 30-day stroke or death, 30-day stroke, myocardial infarction, or death, 30-day all-cause mortality, and 1-year stroke.

RESULTS

During the study, 937 111 unique patients underwent carotid endarterectomy (mean age, 75.8 years; 43% women) and 231 077 underwent carotid artery stenting (mean age, 75.4 years; 49% women). There were 81 306 patients who underwent endarterectomy in 1999 and 36 325 in 2014; national rates per 100 000 beneficiary-years decreased from 298 in 1999-2000 to 128 in 2013-2014 (P < .001). The number of patients who underwent stenting ranged from 10 416 in 1999 to 22 865 in 2006 (an increase per 100 000 beneficiary-years from 40 in 1999-2000 to 75 in 2005-2006; P < .001); by 2014, there were 10 208 patients who underwent stenting and the rate decreased to 38 per 100 000 beneficiary-years (P < .001). Outcomes improved over time despite increases in vascular risk factors (eg, hypertension prevalence increased from 67% to 81% among patients who underwent endarterectomy and from 61% to 70% among patients who underwent stenting) and the proportion of symptomatic patients (all P < .001). There were adjusted annual decreases in 30-day ischemic stroke or death of 2.90% (95% CI, 2.63% to 3.18%) among patients who underwent endarterectomy and 1.13% (95% CI, 0.71% to 1.54%) among patients who underwent stenting; an absolute decrease from 1999 to 2014 was observed for endarterectomy (1.4%; 95% CI, 1.2% to 1.5%) but not stenting (-0.1%; 95% CI, -0.5% to 0.4%). Rates for 1-year ischemic stroke decreased after endarterectomy (absolute decrease, 3.5% [95% CI, 3.2% to 3.7%]; adjusted annual decrease, 2.17% [95% CI, 2.00% to 2.34%]) and stenting (absolute decrease, 1.6% [95% CI, 1.2% to 2.1%]; adjusted annual decrease, 1.86% [95% CI, 1.45%-2.26%]). Additional improvements were noted for in-hospital mortality, 30-day stroke, myocardial infarction, or death, and 30-day all-cause mortality as well as within demographic subgroups.

CONCLUSIONS AND RELEVANCE

Among fee-for-service Medicare beneficiaries, the performance of carotid endarterectomy declined from 1999 to 2014, whereas the performance of carotid artery stenting increased until 2006 and then declined from 2007 to 2014. Outcomes improved despite increases in vascular risk factors.

Ethnicity, Race, and Postoperative Stroke Risk Among 53,593 Patients with Asymptomatic Carotid Stenosis Undergoing Revascularization

BACKGROUND

The incidence of postoperative stroke after carotid endarterectomy is an uncommon event, and differences by racial and ethnic subgroups are not described fully in the literature.

OBJECTIVE

To investigate the impact of race and ethnicity on postoperative stroke risk among patients with asymptomatic carotid stenosis undergoing carotid endarterectomy.

METHODS

The American College of Surgeons National Surgical Quality Improvement Program database was searched for patients between the dates 2008 and 2015 to identify patients undergoing carotid endarterectomy with no history of stroke. Four racial and ethnic subgroups were included: non-Hispanic white, Hispanic white, non-Hispanic back, and non-Hispanic Asian. In addition to a descriptive statistical analysis, univariate and multivariate regression models were created to adjust for cardiovascular and perioperative risk factors and corrected for multiple comparisons.

RESULTS

Among the 53,593 patients identified meeting the inclusion criteria, 788 (1.45%) patients experienced a stroke within 30 days. The non-Hispanic white group compared with the minority subgroups had a lower risk of postoperative stroke (1.43% vs. 1.67%, P = 0.18). The greatest difference was between the non-Hispanic white and Hispanic white groups, but this was not significant on multivariable analysis (odds ratio 1.40, 95% confidence interval 0.97-2.02, P = 0.08) after adjustment for risk stroke factors. The strongest predictors of postoperative stroke were perioperative blood transfusion, dependent functional status, and longer operative time.

CONCLUSIONS

There was no difference between the racial and ethnic groups and the proportion of postoperative stroke among patients undergoing revascularization for asymptomatic carotid stenosis.

Race as a predictor of delay from diagnosis to endarterectomy in clinically significant carotid stenosis

OBJECTIVE

Prompt carotid endarterectomy (CEA) in clinically significant carotid stenosis is important in the prevention of neurologic sequelae. The greatest benefit from surgery is obtained by prompt revascularization on diagnosis. It has been demonstrated that black patients both receive CEA less frequently than white patients do and experience worse postoperative outcomes. We sought to test our hypothesis that black race is an independent risk factor for a prolonged time from sonographic diagnosis of carotid stenosis warranting surgery to the day of operation (TDO).

METHODS

From 1998 to 2013 at a single institution, 166 CEA patients were retrospectively reviewed using Synthetic Derivative, a de-identified electronic medical record. Factors potentially affecting TDO, including demographics, preoperative cardiac stress testing, degree of stenosis, smoking status, and comorbidities, were noted. Multivariate analysis was performed on variables that trended with prolonged TDO on univariate analysis (P < .10) to determine independent (P < .05) predictors of TDO. Subgroup analyses were further performed on the symptomatic and asymptomatic stenosis cohorts.

RESULTS

There were 32 black patients and 134 white patients studied; the mean TDO was 78 ± 17 days vs 33 ± 3 days, respectively (P < .001). In addition to the need for preoperative cardiac stress testing, black race was the only variable that demonstrated a trend with (P < .10) or was an independent risk factor for (P < .05) prolonged TDO among all patients (B = 42 days; P < .001) and within the symptomatic (B = 35 days; P = .08) and asymptomatic (B = 35 days; P = .003) cohorts. On Kaplan-Meier analysis, black patients in each stratum of symptomatology (all, symptomatic, and asymptomatic patients) experienced prolonged TDO (log-rank, P < .03 for all three groups).

CONCLUSIONS

Black race is a risk factor for a temporal delay in CEA for carotid stenosis. Awareness of this disparity may help surgeons avoid undesirable delays in operation for their black patients.

Creatine kinase inhibits ADP-induced platelet aggregation

Bleeding risk with antiplatelet therapy is an increasing clinical challenge. However, the inter-individual variation in this risk is poorly understood. We assessed whether the level of plasma creatine kinase, the enzyme that utilizes ADP and phosphocreatine to rapidly regenerate ATP, may modulate bleeding risk through a dose-dependent inhibition of ADP-induced platelet activation. Exogenous creatine kinase (500 to 4000 IU/L, phosphocreatine 5 mM) added to human plasma induced a dose-dependent reduction to complete inhibition of ADP-induced platelet aggregation. Accordingly, endogenous plasma creatine kinase, studied in 9 healthy men (mean age 27.9 y, SE 3.3; creatine kinase 115 to 859 IU/L, median 358), was associated with reduced ADP-induced platelet aggregation (Spearman's rank correlation coefficient, -0.6; p < 0.05). After exercise, at an endogenous creatine kinase level of 4664, ADP-induced platelet aggregation was undetectable, normalizing after rest, with a concomitant reduction of creatine kinase to normal values. Thus, creatine kinase reduces ADP-induced platelet activation. This may promote bleeding, in particular when patients use platelet P2Y12 ADP receptor inhibitors.