Citations

Background: Presence of atherosclerotic disease in more than one vascular bed (polyvascular disease) is associated with an increased risk of long-term vascular events. In the setting of asymptomatic carotid stenosis, the predictors of disease in other vascular beds is not well delineated. Objective: To identify the frequency and predictors of disease in other vascular beds the CREST 2 randomized trial population with hemodynamically significant stenosis. Methods: Recorded baseline characteristics among CREST 2 participants included: demographics, past medical history, lifestyle factors, and laboratory studies. Each variable was tested against three potential definitions of disease in other beds (cardiac, peripheral arterial disease (PAD) or disease in cardiac + PAD). Statistical analysis was done with Chi square and t tests as appropriate. Results: Data from 1447 patients were available for analysis. In these subjects with carotid disease, 51% also had cardiac disease, 24% also had PAD, and 16% had disease in in both cardiac and PAD. There was no relationship between age or race and presence of disease in other beds. Those with cardiac disease were more likely to be male. Diabetes, hypertension, hypercholesterolemia, and former history of smoking were all more common in those with either cardiac and PAD (TABLE). Elevated triglyceride and low HDL levels were also associated with all three definitions of disease in other beds. Those with either PAD or cardiac + PAD were more likely to be current smokers. Conclusions: Among CREST 2 participants, several medical conditions and lifestyle factors were associated with an increased frequency of disease in other vascular beds. Smoking, in particular, appears to be more common in those with PAD. Future analyses will address whether those with disease in other beds have higher rates of stroke or death.

Baseline Differences in Risk Factor Control and Medication Use Between 2 Trials Employing Intensive Medical Management (SAMMPRIS & CREST2) Background: The CREST2 trial Intensive Medical Management (IMM) protocol was adapted from the SAMMPRIS trial. However, since the 2011 publication of initial results of SAMMPRIS, there has been a greater appreciation for the importance of risk factor control in patients at risk of stroke associated with atherosclerosis. Therefore, we sought to determine differences in baseline risk factor control and medication use between SAMMPRIS and CREST2. Methods: Baseline risk factor and medication use data from 451 patients enrolled in SAMMPRIS (2008-2011) with severe symptomatic intracranial atherosclerosis and 1473 patients enrolled in CREST2 (2014-2019) with severe asymptomatic carotid stenosis were compared using the Chi-square test and t-test. Results: The Table shows baseline risk factor values and medications. SAMMPRIS patients were younger but had significantly worse risk factor control than CREST2 patients for all measures. There was no significant difference in statin use at baseline, but the mean SAMMPRIS subjects’ LDL was 16.1 mg/dL higher than in CREST2. CREST2 patients had higher rates of use of angiotensin receptor blockers (ARB), calcium channel blockers (CCB), and thiazides, but lower rates of use of angiotensin converting enzyme (ACE) inhibitors. Conclusions: Despite being older, CREST2 patients have significantly better baseline risk factor profiles than SAMMPRIS patients. This could be due to greater appreciation of the importance of risk factor control and healthy lifestyle habits for stroke prevention or more aggressive treatment targets in guideline recommendations. Although risk factor control appears to be improving since SAMMPRIS, many CREST2 patients are still not meeting recommended risk factor goals at baseline and may benefit from IMM protocols.

Introduction: Using pooled data from randomized trials of symptomatic patients assigned to carotid artery stenting (CAS) versus carotid endarterectomy (CEA), we have previously shown age to be an effect modifier, with increasing risk at older ages for CAS but not for CEA. To extend assessment of age as an effect modifier to the asymptomatic population, we combined the asymptomatic patients from CREST with the patients from ACT I. Methods: We analyzed data from 2544 subjects with >= 70% carotid stenosis randomized to CAS or CEA in addition to standard management of cardiovascular risk factors. CREST enrolled 1091 (548 CAS, 543 CEA) and ACT I enrolled 1453 (1089 CAS, 364 CEA) asymptomatic patients less than 80 years old (upper age eligibility in ACT I). We examined the impact of age on risk within CAS-treated and CEA-treated patients using Kaplan-Meier methods. Age was considered in three strata (< 65, 65 to 74, and 75+). The pre-specified, primary composite endpoint was stroke, myocardial infarction, or death during the periprocedural period or any ipsilateral stroke within 4 years after randomization. Results: For patients assigned to CAS, risk differed between the age strata (p <0.0001) where relative to those under age 65, there was no difference in risk for those aged 65 to 74 (HR = 1.3 ; 95% CI: 0.7, 2.3, p=0.38), but those aged 75+ were at substantially higher risk (HR = 2.9; 95% CI: 1.5, 5.5, p=0.001). In contrast, risk did not differ by age strata (p = 0.80) for those assigned to CEA. Conclusions: Age-related risk factors, e.g. carotid anatomy and underlying cerebral pathology, should be considered before selecting patients aged 75+ for CAS.

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.

Background: Data from the CDC show that approximately one-quarter of adults have elevated triglyceride (TG) levels. Recent trials have demonstrated that pharmacologic treatment of high TG levels, in patients already on statin therapy, reduces the rate of major vascular events such as myocardial infarction and stroke (REDUCE-IT trial). We sought to assess how often patients with asymptomatic carotid stenosis (CS) have elevated TG levels and factors associated with high TG values. Methods: Patients enrolled in the Carotid Revascularization and Medical Management for Asymptomatic Carotid Stenosis Trial (CREST 2) were analyzed. Baseline lipid profiles were evaluated to determine high TG treatment eligibility as per the REDUCE-IT trial. We also evaluated baseline use of pharmacologic treatment for high TG levels. Demographic factors and baseline medical conditions were studied in relation to high (>150 mg/dl) TG values. Chi square and t tests were used to assess baseline factors and abnormal TG values. Results: As of August 10, 2020, 1655 of 1689 randomized patients (mean age 69.7 years, 61% men) had baseline lipid profiles suitable for analysis. Treatment eligibility according to REDUCE-IT (LDL 41-100 mg/dl, TG>150 mg/dl) was present in 21% (345) of subjects. In these patients, the median TG value was 205 (IQR 93) mg/dl. Fibrate medications were used at baseline in 4.5% of patients. Analysis of demographic and medical history factors and TG values greater than 150 mg/dl is found in the Table. There was significant positive correlation between baseline hemoglobin A1C and triglyceride values (p<0.0001) Conclusions: One in five patients in CREST 2 has TG values that potentially justify pharmacologic treatment. Elevated TG levels are most correlated with diabetes, hypertension, obesity, decreased physical activity, and heart disease. Clinicians should investigate treatment of elevated TG levels as a component of intensive medical therapy for stroke prevention.

Introduction: Previous analyses of randomized trials comparing carotid artery stenting (CAS) versus carotid endarterectomy (CEA) have revealed varying sex-associated risk. To better understand sex as an effect modifier in the asymptomatic population, we combined the asymptomatic patients from CREST with the asymptomatic patients from ACT I. Methods: We analyzed data from 2544 subjects with ≥ 70% carotid stenosis randomized to CAS or CEA in addition to standard management of cardiovascular risk factors. CREST enrolled 1091 (548 CAS, 543 CEA) and ACT I enrolled 1453 (1089 CAS, 364 CEA) asymptomatic patients less than 80 years old (upper age eligibility in ACT I). We examined the impact of sex on risk within CAS-treated and CEA-treated patients using Kaplan-Meier methods. The pre-specified, primary composite endpoint was stroke, myocardial infarction, or death during the periprocedural period (within 30 days of randomization) or any ipsilateral stroke within 4 years after randomization. Results: For patients assigned to CAS, there was no difference in risk between the sexes (female-to-male HR = 1.04, 95% CI 0.65 -- 1.66, P = 0.87). For patients assigned to CEA, the difference in risk detected was not significant (female-to-male HR = 1.43, 95% CI 0.77 - 2.67, P = 0.26). Conclusions: Sex-differences in risk were not significant for those assigned CAS nor those assigned CEA in this largest pooled analysis of asymptomatic patients comparing CAS to CEA.

Background and Purpose: CREST (Carotid Revascularization Endarterectomy Versus Stenting Trial) reported a higher periprocedural risk for any stroke, death, or myocardial infarction for women randomized to carotid artery stenting (CAS) compared with women randomized to carotid endarterectomy (CEA). No difference in risk by treatment was detected for women relative to men in the 4-year primary outcome. We aimed to conduct a pooled analysis among symptomatic patients in large randomized trials to provide more precise estimates of sex differences in the CAS-to-CEA risk for any stroke or death during the 120-day periprocedural period and ipsilateral stroke thereafter. Methods: Data from the Carotid Stenosis Trialists’ Collaboration included outcomes from symptomatic patients in EVA-3S (Endarterectomy Versus Angioplasty in Patients With Symptomatic Severe Carotid Stenosis), SPACE (Stent-Protected Angioplasty Versus Carotid Endarterectomy in Symptomatic Patients), ICSS (International Carotid Stenting Study), and CREST. The primary outcome was any stroke or death within 120 days after randomization and ipsilateral stroke thereafter. Event rates and relative risks were estimated using Poisson regression; effect modification by sex was assessed with a sex-by-treatment-by-trial interaction term, with significant interaction defined a priori as P ≤0.10. Results: Over a median 2.7 years of follow-up, 433 outcomes occurred in 3317 men and 1437 women. The CAS-to-CEA relative risk of the primary outcome was significantly lower for women compared with men in 1 trial, nominally lower in another, and nominally higher in the other two. The sex-by-treatment-by-trial interaction term was significant ( P =0.065), indicating heterogeneity among trials. Contributors to this heterogeneity are primarily differences in periprocedural period. When the trials are nevertheless pooled, there were no significant sex differences in risk in any follow-up period. Conclusions: There were significant differences between trials in the magnitude of sex differences in treatment effect (CAS-to-CEA relative risk), indicating pooling data from these trials to estimate sex differences might not be valid. Whether sex is acting as an effect modifier of the CAS-to-CEA treatment effect in symptomatic patients remains uncertain. Registration: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT00190398 (EVA-3S) and NCT00004732 (CREST). URL: https://www.isrctn.com ; Unique identifier: ISRCTN57874028 (SPACE) and ISRCTN25337470 (ICSS).

Abstract Purpose: Irinotecan/5-fluorouracil (5-FU; FOLFIRI) or oxaliplatin/5-FU (FOLFOX), combined with bevacizumab or cetuximab, are approved, first-line treatments for metastatic colorectal cancer (mCRC). We aimed at identifying germline variants associated with survival in patients with mCRC treated with these regimens in Cancer and Leukemia Group B/SWOG 80405. Experimental Design: Patients with mCRC receiving either FOLFOX or FOLFIRI were randomized to either cetuximab or bevacizumab. DNA from peripheral blood was genotyped for approximately 700,000 SNPs. The association between SNPs and overall survival (OS) was tested in 613 patients of genetically estimated European ancestry using Cox proportional hazards models. Results: The four most significant SNPs associated with OS were three haplotypic SNPs between microsomal glutathione S-transferase 1 (MGST1) and LIM domain only 3 (LMO3, representative HR, 1.56; P = 1.30 × 10−6), and rs11644916 in AXIN1 (HR, 1.39, P = 4.26 × 10−6). AXIN1 is a well-established tumor suppressor gene in colorectal cancer, and rs11644916 (G&gt;A) conferred shorter OS. Median OS for patients with the AA, AG, or GG genotypes was 18.4, 25.6, or 36.4 months, respectively. In 90 patients with stage IV colorectal cancer from The Cancer Genome Atlas (TCGA), rs11649255 in AXIN1 [in almost complete linkage disequilibrium (LD) with rs11644916], was associated with shorter OS (HR, 2.24, P = 0.0096). Using rs11648673 in AXIN1 (in very high LD with rs11644916 and with functional evidence), luciferase activity in three colorectal cancer cell lines was reduced. Conclusions: This is the first large genome-wide association study ever conducted in patients with mCRC treated with first-line standard treatment in a randomized phase III trial. A common SNP in AXIN1 conferred worse OS and the effect was replicated in TCGA. Further studies in colorectal cancer experimental models are required.

Background and Purpose: The CREST2 trial (Carotid Revascularization and Medical Management for Asymptomatic Carotid Stenosis) is comparing intensive medical management (IMM) alone to IMM plus revascularization with carotid endarterectomy or transfemoral carotid artery stenting for preventing stroke or death within 44 days after randomization or ipsilateral ischemic stroke thereafter. There are extensive clinical trial data on outcomes after revascularization of asymptomatic carotid stenosis, but not for IMM. As such, the experimental treatment in CREST2 is IMM, which is described in this article. Methods: IMM consists of aspirin 325 mg/day and intensive risk factor management, primarily targeting systolic blood pressure <130 mm Hg (initially systolic blood pressure <140 mm Hg) and LDL (low-density lipoprotein) cholesterol <70 mg/dL. Secondary risk factor targets focus on tobacco smoking, non-HDL (high-density lipoprotein), HbA1c (hemoglobin A1c), physical activity, and weight. Risk factor management is performed by site personnel and a lifestyle coaching program delivered by telephone. We report interim risk factor data on 1618 patients at baseline and last follow-up through 24 months. Results: The mean baseline LDL of 80.5 mg/dL improved to 66.7 mg/dL. The mean baseline systolic blood pressure of 139.7 mm Hg improved to 130.3 mm Hg. The proportion of patients in-target improved from 43% to 61% for systolic blood pressure <130 mm Hg and from 45% to 67% for LDL<70 mg/dL (both changes P <0.001). Conclusions: The rigorous multimodal approach to intensive stroke risk factor management in CREST2 has resulted in significant improvements in risk factor control that will enable a comparison of cutting-edge medical care to revascularization in patients with asymptomatic carotid stenosis. Registration: URL: https://www.clinicaltrials.gov . Unique identifier: NCT02089217.