Citations

Introduction: Inclusion of asymptomatic patients in randomized trials comparing revascularization to medical therapy has been questioned if they have been previously symptomatic. Hypothesis: Duration of asymptomatic status is not associated with better outcomes following endarterectomy (CEA) or stenting (CAS). Methods: Patients in CREST were classified as asymptomatic if they had not had a TIA or stroke ipsilateral to the study artery within 6 months prior to randomization. We compared those patients who had always been asymptomatic (AA) to those who had been previously symptomatic (PS) ≥ 6 months prior to randomization. Proportional hazards models adjusting for age and treatment were used to assess risk of 30-day stroke or death (S+D), and risk of any 30-day S+D plus ipsilateral stroke at 4 years by asymptomatic status Results: Among the 1056 asymptomatic patients who received the assigned procedure within 30 days of randomization, 977 (93%) were AA and 79 (7%) were PS. There was no difference in the 30-day and 4 year outcomes (Table). Conclusion: In CREST, 93% of the asymptomatic patients were always asymptomatic. Similar outcomes for the previously symptomatic patients (7%) supports the inclusion of such patients in randomized trials comparing CEA and CAS to medical treatment.

Background: Carotid revascularization was addressed by NASCET and ACAS. NASCET showed a 2-year stroke and death of 32.3% in medical patients and a 15.8% incidence in surgical patients (16.5% absolute/51% relative reduction). Similarly, ACAS revealed an 11% 5-year risk in medical patients and 5.1% in surgical patients (5.9% absolute reduction/53% relative reduction). Absolute risk (rather than relative risk) reduction is of prime interest to the patient. However, in these studies, treatment efficacy was assessed on a relative basis, and these procedures were equally efficacious (51% vs. 53% relative risk). The higher event rates in the symptomatic patients resulted in a larger absolute risk reduction in NASCET (16.5% vs. 5.9%). CREST is the only carotid revascularization study to include both symptomatic and asymptomatic patients undergoing CEA or carotid artery stenting (CAS), and we looked at absolute and relative risks associated with both procedures. Methods: Treatment differences in CREST by symptomatic status were reviewed and interaction terms analyzed. Results: Symptomatic periprocedural stroke and death rates were 6% for CAS vs. 3.2% for CEA (2.8% absolute/47% relative difference/p = 0.02), and were 2.5% for CAS vs. 1.4% for CEA (1.2% absolute/53% relative difference/p = 0.15) for asymptomatic. While treatment differences in periprocedural rates were significant for symptomatic but not asymptomatic patients, there was no difference in treatment efficacy as determined by relative risk reduction. Even the most prominent interaction terms were clearly not significant, p > 0.38. Discussion: There is no evidence of a CAS-CEA difference in treatment efficacy by symptomatic status in CREST. There are significant findings in symptomatic patients. This is likely a product of an increased background rate of events in this strata. While symptomatic status can identify a subgroup with an increased background rate, other factors (e.g. age or stenosis) could identify subgroups of asymptomatic patients with high event rates and large absolute treatment differences.

Background: Stroke symptoms in the general population are common (≈18% of adults 45+) and are associated with future stroke. These symptoms may also identify a broad spectrum of clinically-undetected vascular conditions. Methods: Stroke symptoms (sudden weakness, numbness, unilateral or general loss of vision, and loss of ability to communicate or understand) and time to self-reported hospitalization for any cardiovascular (CVD) reason (heart, stroke, or TIA) or stroke were assessed in the REGARDS Study (a national, population-based, longitudinal study of 30,239 African-American and white adults > 45 years enrolled 2003-2007). The symptom-hospitalization association was assessed by proportional hazards analysis in persons stroke/TIA-free at baseline, with adjustment for demographics (age, race and sex), further adjustment for SES (income and education), CVD risk factors (smoking, hypertension, diabetes, dyslipidemia, atrial fibrillation and heart disease), and “perceived health status.” Results: Over an average follow-up of 5.6 years, presence of any stroke symptom was associated with greater risk of hospitalization for stroke (11% versus 6%; HR = 1.68; 95% CI: 1.52 - 1.85), a risk only modestly attenuated by adjustment for SES (HR = 1.59; 95% CI: 1.44 - 1.76), risk factors (HR = 1.44; 95% CI: 1.29 - 1.60), and perceived health (HR = 1.37; 95% CI: 1.23 - 1.53). However, presence of any stroke symptom was more strongly related to hospitalization for CVD (42% vs. 24%; HR = 1.92; 95 CI: 1.82 - 2.03), only modestly mediated by adjustment for SES (HR = 1.82; 95% CI: 1.73 - 1.93), risk factors (HR = 1.66; 95% CI: 1.57 - 1.76), and perceived health (HR = 1.57; 95% CI: 1.48 - 1.66). Conclusions: Stroke symptoms appear to be a marker not only for stroke risk, but also for general CVD. Simple questions can identify 18% of the general population that have over a 40% chance of hospitalization for CVD over a 5-year horizon. Implications for potential intervention to reduce risk are profound.

Background: CREST, a randomized trial comparing carotid artery stenting (CAS) with endarterectomy (CEA) in symptomatic and asymptomatic patients, reported in 2010 that the two procedures were similar for the composite endpoint of stroke, myocardial infarction, or death. Data on temporal trends in the use of these procedures in the US are limited, particularly by sex, race, and geographic region. We reviewed trends in utilization of CAS and CEA for ischemic stroke patients. Methods: Ischemic stroke hospitalizations (ICD-9 433, 434, 436) were identified for patients aged ≥18 years from the Nationwide Inpatient Sample 2007-2011 (N=480,375). Annual trends of CAS and CEA were estimated using mixed models that adjusted for patient age and comorbidities. Models were stratified by sex, race (white, black, other), and 9 geographic regions. Results: Overall, the proportion of stroke patients who received CAS remained relatively stable over time (2.7% in 2007 to 2.8% in 2011) while the proportion who received CEA decreased (from 21.0% to 16.3%). CAS rates increased in the three Central Regions (East North, East South, and West South) but decreased in New England; CEA declines were similar across regions. In adjusted analyses, CAS rates increased slightly for white men, decreased for men and women of other race, but remained stable for the remaining groups (Figure); CEA rates decreased for all sex-race groups. These patterns by sex and race subgroups were generally consistent across geographic regions. Conclusions: The proportion of hospitalized stroke patients receiving CEA decreased over time while CAS rates remained relatively stable, with slight increases seen in the Central regions of the US. There are sex-race differences in the proportion of patients who receive these procedures, but these patterns are largely similar across regions.

Purpose: The safety of revascularization for asymptomatic carotid stenosis, and the efficacy of medical therapy for stroke prevention have improved. Therefore, results of prior randomized trials may not apply to current treatment decisions. The NINDS-funded CREST-2 will compare carotid endarterectomy and intensive medical therapy (IMT) versus IMT alone (n=1240), and carotid stenting and IMT versus IMT alone (n=1240) in asymptomatic patients with≥70% stenosis. Materials & Methods: CREST-2 consists of two parallel randomized clinical trials to be conducted at a target of ≈120 centers, including within NINDS StrokeNet. The composite primary outcome is stroke or death during the peri-procedural period or ipsilateral ischemic stroke thereafter up to 4 years. Blinded assessment of cognition will be done periodically. Centrally directed IMT includes tight control of blood pressure (systolic target <140 mm Hg) and cholesterol (LDL target <70 mg/dl) as well as lifestyle coaching. Results: As of June 12, 2015, 94 centers have been approved by the Site Selection Committee. Credentialing is ongoing, with 198 approved surgeons and 64 approved interventionists; 124 additional conditionally approved interventionists will be able to submit additional cases for review under the CREST-2 Registry. The Centers for Medicare and Medicaid will offer CAS reimbursement for Registry enrollees. As of June 12, 2015, there are 39 actively enrolling centers, and 37 patients have been randomized. Conclusion: CREST-2 is designed to identify the best approach for asymptomatic carotid stenosis. The first patient was randomized in December, 2014. An update will be provided regarding the numbers of patients randomized, centers certified, as well as surgeons and interventionists fully approved. Registration: ClinicalTrials.gov Identifier: NCT02089217

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: Careful selection and timely activation of clinical sites in multicenter clinical trials is critical for successful enrollment, subject safety, and generalizability of results. Methods: In the Carotid Revascularization and Medical Management for Asymptomatic Carotid Stenosis Trial (CREST-2), a multidisciplinary Site Selection Committee evaluated applicants referred via participation in CREST, CREST principal investigators (PIs) and other investigators, StrokeNet and industry partners. Data for consideration included performance metrics in CREST and other carotid trials and a site selection questionnaire containing information on the investigators as well as quantitative data on carotid procedures performed. Any FDA warning letters were reviewed. Results: The Committee met bi-weekly for 36 months (n=64 meetings). Applications from 176 sites between March 2014 and July 2016 were evaluated: 153 were approved, 7 are under Committee review, 5 were approved but withdrew, 5 were placed on a waiting list, and 6 were rejected. One-hundred-four sites have completed the regulatory and training requirements to randomize: 51 (49%) academic medical centers, 31 (30%) private hospital-based centers, 16 (15%) private office-based practices, and 6 (6%) Veterans Administration medical centers. The mean times from application-to- approval was 5.2 weeks (interquartile range, 1.9, 6.2), and from approval-to-randomization status was 46.7 weeks (interquartile range, 35.4, 51.7). Specialties of the 104 site PIs are vascular surgery for 35 (33.7%), cardiology for 30 (28.8%), neurology for 25 (24%), neurosurgery for 8 (7.7%), interventional radiology for 4 (3.8%), and interventional neuroradiology for 2 (1.9%). Conclusions: Careful site selection is time-consuming for prospective sites and for trial leadership. Times from application-to-site-approval were modest (mean = 5.2 weeks), in contrast to the times for completing regulatory and training requirements (mean = 46.7 weeks). However, subject enrollment by teams from a wide range of medical centers led by a multi-disciplinary cohort of PIs will promote the generalizability of trial results.

Background: Concern for underrepresentation of minorities in clinical trials has focused on enrollment proportions and generalizability. The interplay of trial event-rates with diversity has not been emphasized. Methods: The Carotid Revascularization Endarterectomy vs Stent Trial (CREST) randomized 2502 patients and compared them by race, ethnicity, baseline characteristics, and primary outcome (any peri-procedural stroke, death or MI and subsequent ipsilateral stroke up to 10 years); those with unknown race or ethnicity were excluded. Proportional hazards models adjusting for age, sex, symptomatic status and treatment were used to test for a treatment by race/ethnicity interaction. Results: One-hundred-nine patients (4.4%) were black, 32 (1.3%) Asian, 2332 (93.4%) white, 11 (0.4%) other by self-report, and 18 (0.7%) unknown; 90 (3.6%) were Hispanic, 2377 (95%) non-Hispanic, and 35 (1.4%) unknown. Compared to whites, racial minorities were younger (mean age 67±8.9 vs 69±8.8, p=0.004), more often female (44% vs 34%, p=0.01), symptomatic (63 vs 52%, p=0.01), and diabetic (51% vs 29%, p<0.0001), but less often dyslipidemic (76% vs 85%, p=0.004), current smokers (19% vs 27%, p=0.04), or had a history of cardiovascular disease (34% vs 46%, p=0.007). Hispanics were more often diabetic (48% vs 30%, p=0.0002). The rate of the primary endpoint was 10.9%±0.9% at 10 years, and did not differ by race or ethnicity (p inter >0.24). In the context of this low rate, even if minority recruitment were increased to represent 50% of study participants, and if the treatment difference in one race were a greater hazard of HR = 1.49 (anticipated alternative hypothesis), then the hazard ratio in the other group would need to be <0.73, or >3.31, to have 90% power of detection. Conclusions: The proportion of racial and ethnicity participation in CREST was suboptimal at < 10%. Primary outcomes did not differ by minority or ethnic status. However, in low event-rate trials very high and even unrealistic enrollment goals for diversity, for example ≥50%, may still be insufficient for detection of outcome differences by race or ethnicity.

OBJECTIVES: To characterize the pediatric super-refractory status epilepticus population by describing treatment variability in super-refractory status epilepticus patients and comparing relevant clinical characteristics, including outcomes, between super-refractory status epilepticus, and nonsuper-refractory status epilepticus patients. DESIGN: Retrospective cohort study with prospectively collected data between June 2011 and January 2019. SETTING: Seventeen academic hospitals in the United States. PATIENTS: We included patients 1 month to 21 years old presenting with convulsive refractory status epilepticus. We defined super-refractory status epilepticus as continuous or intermittent seizures lasting greater than or equal to 24 hours following initiation of continuous infusion and divided the cohort into super-refractory status epilepticus and nonsuper-refractory status epilepticus groups. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: We identified 281 patients (157 males) with a median age of 4.1 years (1.3–9.5 yr), including 31 super-refractory status epilepticus patients. Compared with nonsuper-refractory status epilepticus group, super-refractory status epilepticus patients had delayed initiation of first nonbenzodiazepine-antiseizure medication (149 min [55–491.5 min] vs 62 min [33.3–120.8 min]; p = 0.030) and of continuous infusion (495 min [177.5–1,255 min] vs 150 min [90–318.5 min]; p = 0.003); prolonged seizure duration (120 hr [58–368 hr] vs 3 hr [1.4–5.9 hr]; p < 0.001) and length of ICU stay (17 d [9.5–40 d] vs [1.8–8.8 d]; p < 0.001); more medical complications (18/31 [58.1%] vs 55/250 [22.2%] patients; p < 0.001); lower return to baseline function (7/31 [22.6%] vs 182/250 [73.4%] patients; p < 0.001); and higher mortality (4/31 [12.9%] vs 5/250 [2%]; p = 0.010). Within the super-refractory status epilepticus group, status epilepticus resolution was attained with a single continuous infusion in 15 of 31 patients (48.4%), two in 10 of 31 (32.3%), and three or more in six of 31 (19.4%). Most super-refractory status epilepticus patients (30/31, 96.8%) received midazolam as first choice. About 17 of 31 patients (54.8%) received additional treatments. CONCLUSIONS: Super-refractory status epilepticus patients had delayed initiation of nonbenzodiazepine antiseizure medication treatment, higher number of medical complications and mortality, and lower return to neurologic baseline than nonsuper-refractory status epilepticus patients, although these associations were not adjusted for potential confounders. Treatment approaches following the first continuous infusion were heterogeneous, reflecting limited information to guide clinical decision-making in super-refractory status epilepticus.