Strokes Averted by Intravenous Thrombolysis: A Secondary Analysis of a Prospective, Multicenter, Controlled Trial of Mobile Stroke Units.

OBJECTIVE: This study was undertaken to examine averted stroke in optimized stroke systems. METHODS: This secondary analysis of a multicenter trial from 2014 to 2020 compared patients treated by mobile stroke unit (MSU) versus standard management. The analytical cohort consisted of participants with suspected stroke treated with intravenous thrombolysis. The main outcome was a tissue-defined averted stroke, defined as a final diagnosis of stroke with resolution of presenting symptoms/signs by 24 hours attributed to thrombolysis and no acute infarction/hemorrhage on imaging. An additional outcome was stroke with early symptom resolution, defined as a final diagnosis of stroke with resolution of presenting symptoms/signs by 24 hours attributed to thrombolysis. RESULTS: Among 1,009 patients with a median last known well to thrombolysis time of 87 minutes, 159 (16%) had tissue-defined averted stroke and 276 (27%) had stroke with early symptom resolution. Compared with standard management, MSU care was associated with more tissue-defined averted stroke (18% vs 11%, adjusted odds ratio [aOR] = 1.82, 95% confidence interval [CI] = 1.13-2.98) and stroke with early symptom resolution (31% vs 21%, aOR = 1.74, 95% CI = 1.12-2.61). The relationships between thrombolysis treatment time and averted/early recovered stroke appeared nonlinear. Most models indicated increased odds for stroke with early symptom resolution but not tissue-defined averted stroke with earlier treatment. Additionally, younger age, female gender, hyperlipidemia, lower National Institutes of Health Stroke Scale, lower blood pressure, and no large vessel occlusion were associated with both tissue-defined averted stroke and stroke with early symptom resolution. INTERPRETATION: In optimized stroke systems, 1 in 4 patients treated with thrombolysis recovered within 24 hours and 1 in 6 had no demonstrable brain injury on imaging. ANN NEUROL 2024;95:347-361.

Outcomes of patients with pre-existing disability managed by mobile stroke units: A sub-analysis of the BEST-MSU study.

BACKGROUND: Few data exist on acute stroke treatment in patients with pre-existing disability (PD) since they are usually excluded from clinical trials. A recent trial of mobile stroke units (MSUs) demonstrated faster treatment and improved outcomes, and included PD patients. AIM: To determine outcomes with tissue plasminogen activator (tPA), and benefit of MSU versus management by emergency medical services (EMS), for PD patients. METHODS: Primary outcomes were utility-weighted modified Rankin Scale (uw-mRS). Linear and logistic regression models compared outcomes in patients with versus without PD, and PD patients treated by MSU versus standard management by EMS. Time metrics, safety, quality of life, and health-care utilization were compared. RESULTS: Of the 1047 tPA-eligible ischemic stroke patients, 254 were with PD (baseline mRS 2-5) and 793 were without PD (baseline mRS 0-1). Although PD patients had worse 90-day uw-mRS, higher mortality, more health-care utilization, and worse quality of life than non-disabled patients, 53% returned to at least their baseline mRS, those treated faster had better outcome, and there was no increased bleeding risk. Comparing PD patients treated by MSU versus EMS, 90-day uw-mRS was 0.42 versus 0.36 (p = 0.07) and 57% versus 46% returned to at least their baseline mRS. There was no interaction between disability status and MSU versus EMS group assignment (p = 0.67) for 90-day uw-mRS. CONCLUSION: PD did not prevent the benefit of faster treatment with tPA in the BEST-MSU study. Our data support inclusion of PD patients in the MSU management paradigm.

Golden Hour Treatment With tPA (Tissue-Type Plasminogen Activator) in the BEST-MSU Study.

BACKGROUND: Treatment of patients with acute ischemic stroke on mobile stroke units (MSUs) improves outcomes compared with management by standard emergency medical services ambulances and is associated with more patients treated with intravenous tPA (tissue-type plasminogen activator) in the first golden hour after last known normal. We explored the predictors and outcomes of first-hour treatment (FHT) compared with later treatment in an alternating-week cluster-controlled trial of MSUs. METHODS: We analyzed all patients treated with intravenous tPA in the BEST-MSU Study (Benefits of Stroke Treatment Delivered by a Mobile Stroke Unit Compared to Standard Management by Emergency Medical Services). After stratifying by treatment timeframe, we identified factors associated with FHT. We performed adjusted analyses of the association between FHT and clinical outcome and modeled the shape of the relationship between last known normal-to-treatment time and excellent outcome. RESULTS: Among 941 tPA-treated patients, 206 (21.8%) had lytic started within 60 minutes. Treatment on the MSU, older age, male sex, alert by 911, faster arrival on-scene and imaging, more severe stroke, atrial fibrillation, and absence of heart failure and pretreatment antihypertensive treatment were associated with FHT. Compared with later treatment, FHT was associated with higher adjusted odds ratio for 90-day modified Rankin Scale score of 0 to 1 (odds ratio, 1.87 [95% CI, 1.25-2.84]; P=0.003). Among FHT patients, 68% achieved a 90-day modified Rankin Scale of 0 or 1 or returned to their baseline status. FHT was not associated with higher risk of hemorrhage and was associated with reduced risk of treating neurovascular mimics. CONCLUSIONS: FHT almost doubles the odds of excellent clinical outcome without increased risk compared with later treatment, which supports the use of MSUs.

Prospective, Multicenter, Controlled Trial of Mobile Stroke Units.

BACKGROUND: Mobile stroke units (MSUs) are ambulances with staff and a computed tomographic scanner that may enable faster treatment with tissue plasminogen activator (t-PA) than standard management by emergency medical services (EMS). Whether and how much MSUs alter outcomes has not been extensively studied. METHODS: In an observational, prospective, multicenter, alternating-week trial, we assessed outcomes from MSU or EMS management within 4.5 hours after onset of acute stroke symptoms. The primary outcome was the score on the utility-weighted modified Rankin scale (range, 0 to 1, with higher scores indicating better outcomes according to a patient value system, derived from scores on the modified Rankin scale of 0 to 6, with higher scores indicating more disability). The main analysis involved dichotomized scores on the utility-weighted modified Rankin scale (≥0.91 or <0.91, approximating scores on the modified Rankin scale of ≤1 or >1) at 90 days in patients eligible for t-PA. Analyses were also performed in all enrolled patients. RESULTS: We enrolled 1515 patients, of whom 1047 were eligible to receive t-PA; 617 received care by MSU and 430 by EMS. The median time from onset of stroke to administration of t-PA was 72 minutes in the MSU group and 108 minutes in the EMS group. Of patients eligible for t-PA, 97.1% in the MSU group received t-PA, as compared with 79.5% in the EMS group. The mean score on the utility-weighted modified Rankin scale at 90 days in patients eligible for t-PA was 0.72 in the MSU group and 0.66 in the EMS group (adjusted odds ratio for a score of ≥0.91, 2.43; 95% confidence interval [CI], 1.75 to 3.36; P<0.001). Among the patients eligible for t-PA, 55.0% in the MSU group and 44.4% in the EMS group had a score of 0 or 1 on the modified Rankin scale at 90 days. Among all enrolled patients, the mean score on the utility-weighted modified Rankin scale at discharge was 0.57 in the MSU group and 0.51 in the EMS group (adjusted odds ratio for a score of ≥0.91, 1.82; 95% CI, 1.39 to 2.37; P<0.001). Secondary clinical outcomes generally favored MSUs. Mortality at 90 days was 8.9% in the MSU group and 11.9% in the EMS group. CONCLUSIONS: In patients with acute stroke who were eligible for t-PA, utility-weighted disability outcomes at 90 days were better with MSUs than with EMS. (Funded by the Patient-Centered Outcomes Research Institute; BEST-MSU ClinicalTrials.gov number, NCT02190500.).

Successful conduct of an acute stroke clinical trial during COVID.

Most clinical research stopped during COVID due to possible impact on data quality and personnel safety. We aimed to assess the impact of COVID on acute stroke clinical trial conduct at sites that continued to enroll patients during the pandemic. BEST-MSU is an ongoing study of Mobile Stroke Units (MSU) vs standard management of tPA-eligible acute stroke patients in the pre-hospital setting. MSU personnel include a vascular neurologist via telemedicine, and a nurse, CT technologist, paramedics and emergency medicine technicians on-board. During COVID, consent, 90-day modified Rankin Scale (mRS) and EQ5D were obtained by phone instead of in-person, but other aspects of management were similar to the pre-COVID period. We compared patient demographics, study metrics, and infection of study personnel during intra- vs pre-COVID eras. Five of 6 BEST-MSU sites continued to enroll during COVID. There were no differences in intra- (n = 57) vs pre- (n = 869) COVID enrolled tPA eligible patients' age, sex, race (38.6% vs 38.0% Black), ethnicity (15.8% vs 18.6% Hispanic), or NIHSS (median 11 vs 9). The percent of screened patients enrolled and adjudicated tPA eligible declined from 13.6% to 6.6% (p < .001); study enrollment correlated with local stay-at-home and reopening orders. There were no differences in alert to MSU arrival or arrival to tPA times, but MSU on-scene time was 5 min longer (p = .01). There were no differences in ED door to CT, tPA treatment or thrombectomy puncture times, hospital length of stay, discharge disposition, or remote vs in-person 90-day mRS or EQ5D. One MSU nurse tested positive but did not require hospitalization. Clinical research in the pre-hospital setting can be carried out accurately and safely during a pandemic. tPA eligibility rates declined, but otherwise there were no differences in patient demographics, deterioration of study processes, or serious infection of study staff. Trial registration: NCT02190500.

Emergency Consent: Patients' and Surrogates' Perspectives on Consent for Clinical Trials in Acute Stroke and Myocardial Infarction.

Background Emergent informed consent for clinical trials in acute myocardial infarction (AMI) and stroke is challenging. The role and value of consent are controversial, and insufficient data exist regarding patients' and surrogates' experiences. Methods and Results We conducted structured interviews with patients (or surrogates) enrolled in AMI or acute stroke trials at 6 sites between 2011 and 2016. Primary domains included trial recall, consent experiences, and preferences regarding involvement. Descriptive and test statistics were used to characterize responses and explore relationships between key domains and characteristics. Multivariable logistic regression was used to examine associations between key covariates and consent preferences. There were 176 (84 stroke, 92 AMI) completed interviews. Most stroke respondents (82%) were surrogates; all AMI respondents were patients. Average time from trial enrollment to interview was 1.9 years (stroke) and 2.8 years (AMI); 89% of stroke and 62% of AMI respondents remembered being in the trial, and among these respondents, 80% (stroke) and 44% (AMI) remembered reading some of the consent form. Over 90% reported not feeling pressure to enroll, being treated in a caring way, and being treated with dignity. A minority (16% stroke and 26% AMI) reported they would have preferred not to be asked for consent. Just over half (61% stroke and 53% AMI) recalled a postenrollment conversation about the study. Conclusions Most respondents felt they were treated respectfully and were glad they had been asked for consent. Trial recall was relatively low, and many respondents recalled little postenrollment discussion. Further development of context-sensitive approaches to consent is important.

The COAST stroke advance directive: A novel approach to preserving patient autonomy.

Within the field of neurology, there has been limited discussion of how to best respect patient autonomy in patients presenting with an acute stroke, who often have impairments in language and cognition. In addition to performing a detailed neurologic examination and providing a thorough timeline of their current presentation and medical history, these patients and their families are then asked to quickly make critical medical decisions regarding acute stroke therapies (thrombolysis and endovascular therapy). These discussions are often limited by time constraints and inadequate opportunities for patient education regarding acute stroke care. This article discusses some of the challenges of preserving patient autonomy in patients presenting with acute stroke and the advent of a stroke advance directive (Coordinating Options for Acute Stroke Therapy [COAST]) aimed to overcome these obstacles.

Development of a Mobile Tool That Semiautomatically Screens Patients for Stroke Clinical Trials.

BACKGROUND AND PURPOSE: Despite several national coordinated research networks, enrollment in many cerebrovascular trials remains challenging. An electronic tool was needed that would improve the efficiency and efficacy of screening for multiple simultaneous acute clinical stroke trials by automating the evaluation of inclusion and exclusion criteria, improving screening procedures and streamlining the communication process between the stroke research coordinators and the stroke clinicians. METHODS: A multidisciplinary group consisting of physicians, study coordinators, and biostatisticians designed and developed an electronic clinical trial screening tool on a HIPAA (Health Insurance Portability and Accountability Act)-compliant platform. RESULTS: A web-based tool was developed that uses branch logic to determine eligibility for simultaneously enrolling clinical trials and automatically notifies the study coordinator teams about eligible patients. After 12 weeks of use, 225 surveys were completed, and 51 patients were enrolled in acute stroke clinical trials. Compared with the 12 weeks before implementation of the tool, there was an increase in enrollment from 16.5% of patients screened to 23.4% of patients screened (P<0.05). Clinicians and coordinators reported increased satisfaction with the process and improved ease of screening. CONCLUSIONS: We created a semiautomated electronic screening tool that uses branch logic to screen patients for stroke clinical trials. The tool has improved efficiency and efficacy of screening, and it could be adapted for use at other sites and in other medical fields.

Visual Determination of Conjugate Eye Deviation on Computed Tomography Scan Predicts Diagnosis of Stroke Code Patients.

BACKGROUND: Head computed tomography (CT) is critical for stroke code evaluations and often happens prior to completion of the neurological exam. Eye deviation on neuroimaging (DeyeCOM sign) has utility for predicting stroke diagnosis and correlates with National Institutes of Health Stroke Scale (NIHSS) gaze score. We further assessed the utility of the DeyeCOM sign, without complex caliper-based eye deviation calculations, but simply with a visual determination method. METHODS: Patients with initial head CT and final diagnosis from an institutional review board-approved consecutive prospective registry of stroke codes at the University of California, San Diego, were included. Five stroke specialists and 1 neuroradiologist reviewed each CT. DeyeCOM+ patients were compared to DeyeCOM- patients (baseline characteristics, diagnosis, and NIHSS gaze score). Kappa statistics compared stroke specialists to neuroradiologist reads, and visual determination to caliper measurement of DeyeCOM sign. RESULTS: Of 181 patients, 46 were DeyeCOM+. Ischemic stroke was more commonly diagnosed in DeyeCOM+ patients compared to other diagnoses (P = .039). DeyeCOM+ patients were more likely to have an NIHSS gaze score of 1 or higher (P = .006). The NIHSS score of DeyeCOM+ stroke versus DeyeCOM- stroke patients was 8.3 ± 6.0 versus 6.7 ± 8.0 (P = .065). Functional outcomes were similar (P = .59). Stroke specialists had excellent agreement with the neuroradiologist (Κ = .89). Visual inspection had excellent agreement with the caliper method (Κ = .88). CONCLUSIONS: Using a time-sensitive visual determination of gaze deviation on imaging was predictive of ischemic stroke diagnosis and presence of NIHSS gaze score, and was consistent with the more complex caliper method. This study furthers the clinical utility of the DeyeCOM sign for predicting ischemic strokes.

Accuracy of First Recorded "Last Known Normal" Times of Stroke Code Patients.

BACKGROUND: Given the time sensitivity of thrombolytic therapy, the accurate documentation of last known normal (LKN) time is crucial to ensure optimal management of stroke patients. This study investigates whether a difference exists between preliminary LKN times (first responders and emergency department practitioners) and revised LKN times (neurology/stroke practitioners), and what potential impact on emergent management of acute stroke this discrepancy may pose. METHODS: All stroke code patients from UC San Diego hospitals from October 2008 to July 2013 with treatment time data were included and grouped based on the disparity between preliminary LKN time and revised LKN time: preliminary earlier than revised, 2 times equal, and preliminary later than revised. We compared baseline characteristics, stroke code intervals, rates of recombinant tissue plasminogen activator (rt-PA) administration, 90-day modified Rankin Scale (mRS) score, discharge disposition, and symptomatic intracerebral hemorrhage. RESULTS: Of 261 patients, 73.6% had disparity between preliminary and revised times: 57.5% had later preliminary LKN than revised, and 16.1% had earlier preliminary LKN than revised. Baseline characteristics, stroke code speed, 90-day mRS score, rates of rt-PA administration, discharge disposition, or rates of symptomatic intracerebral hemorrhage were not significantly different between the groups. Among rt-PA-treated stroke patients whose preliminary time was earlier than the revised time, had the preliminary LKN been used, 29.4% would have had rt-PA withheld inappropriately. In those stroke patients excluded from rt-PA treatment for being outside the treatment window, whose preliminary time was later than the revised time, had the preliminary time been used, 69.7% would have been inappropriately treated outside the relevant rt-PA window. CONCLUSIONS: Most patients had disparity between preliminary and revised LKN times. Had the preliminary LKN time been used for acute stroke decision-making, 58% of patients would have potentially been treated outside the approved thrombolytic time window, with higher risk of adverse events, and 16% may have been inappropriately excluded from thrombolysis. This study highlights the need for training in the determination and refinement of the actual time of stroke onset, especially at hospitals without stroke expertise.

COAST (Coordinating Options for Acute Stroke Therapy): An Advance Directive for Stroke.

BACKGROUND: Stroke is a worldwide problem with a limited number of approved treatments. Obtaining informed consent for acute stroke therapy is complicated by the breadth of information that must be communicated in a short period of time, the hectic nature of the emergency environment, the possible lack of understanding by the patient and/or family, and the critically time-sensitive nature of treatment for stroke. Complicating matters even further, patients are often unable to consent for themselves, placing the burden on surrogates to infer patients' wishes regarding treatment, and potentially limiting acute treatment by practitioners. INNOVATION: An advance directive for acute stroke therapy was created, entitled COAST (Coordinating Options for Acute Stroke Therapy). This clinical initiative is being piloted at a large comprehensive stroke center, including the development of the advance directive form, integration of the form with electronic medical records, training healthcare providers, and outreach to patients. CONCLUSIONS: COAST is an advance directive for stroke designed to make stroke care more efficient, optimize patients' autonomy, improve the quality of healthcare, and streamline the ethical management of complex care decisions in acute stroke. The inherent benefit of COAST is in providing patients and their families with more information regarding stroke and its treatment options, allowing them to take a more active role in their care.

Defining mild stroke: outcomes analysis of treated and untreated mild stroke patients.

BACKGROUND: Mild deficit is a relative contraindication to administration of intravenous recombinant tissue plasminogen activator (IV rtPA) for acute ischemic stroke. However, what constitutes "mild" deficit is vague. Prior studies showed patients with mild strokes have substantial disability rates at hospital discharge and at 90 days. We investigated whether the application of a new definition altered the rates of disability overall and assessed the effects of thrombolysis. METHODS: This analysis included all adult acute ischemic stroke patients from a prospective registry of consecutive patients (University of California San Diego Specialized Programs of Translational Research in Acute Stroke (SPOTRIAS) database, 2003-2014) with 90-day modified Rankin Scale (mRS) score available who were defined as "mild" using either: National Institutes of Health Stroke Scale (NIHSS) 0-5 or a "Re-examining Acute Eligibility for Thrombolysis" (TREAT) Task Force definition (NIHSS 0-5 and nondisabling based on prespecified syndromes). Dichotomized 90-day mRS were compared between treated and untreated patients using the 2 definitions. RESULTS: Of 802 ischemic stroke patients with mRS scores available, 184 had baseline mRS (0) and met TREAT criteria; 45 (24.5%) were rtPA treated. Among the treated patients, 35.6% had 90-day mRS (2-6), versus 28.8% in the untreated group, a nonsignificant difference after adjusting for baseline NIHSS (P = .47). None of the 45 treated patients had symptomatic hemorrhage. Outcomes were similar using the simpler NIHSS 0-5 definition. CONCLUSIONS: About one third of mild stroke patients were not functionally independent at 90 days, irrespective of treatment or mild definition applied, calling into question the treatment efficacy of IV rtPA for mild strokes and what constitutes an appropriate definition of "mild." Randomized studies are necessary to determine rtPA treatment efficacy in mild stroke patients.

Pooled assessment of computed tomography interpretation by vascular neurologists in the STRokE DOC telestroke network.

BACKGROUND AND PURPOSE: The objective of this pooled analysis was to determine the level of agreement between central read and each of 2 groups (spoke radiologists and hub vascular neurologists) in interpreting head computed tomography (CT) scans of stroke patients presenting to telestroke network hospitals. METHODS: The Stroke Team Remote Evaluation Using a Digital Observation Camera (STRokE DOC and STRokE DOC-AZ TIME) trials were prospective, randomized, and outcome blinded comparing telemedicine and teleradiology with telephone-only consultations. In each trial, the CT scans of the subjects were interpreted by the hub vascular neurologist in the telemedicine arm and by the spoke radiologist in the telephone arm. We obtained a central read for each CT using adjudicating committees blinded to treatment arm and outcome. The data were pooled and the results reported for the entire population. Kappa statistics and exact agreement rates were used to assess interobserver agreement for radiographic contraindication to recombinant tissue plasminogen activator (rt-PA), presence of hemorrhage, tumor, hyperdense artery, acute stroke, prior stroke, and early ischemic changes. RESULTS: Among 261 analyzed cases, the agreement with central read for the presence of radiological rt-PA contraindication was excellent for hub vascular neurologist (96.2%, κ = .81, 95% CI .64-.97), spoke radiologist report (94.7%, κ = .64, 95% CI .39-.88), and overall (95.4%, κ = .74, 95% CI .59-.88). For rt-PA-treated patients (N = 65), overall agreement was 98.5%, and vascular neurologist agreement with central read was 100%. CONCLUSIONS: Both vascular neurologists and reports from spoke radiologists had excellent reliability in identifying radiologic rt-PA contraindications. These pooled findings demonstrate that telestroke evaluation of head CT scans for acute rt-PA assessments is reliable.

Imaging negative stroke: diagnoses and outcomes in intravenous tissue plasminogen activator-treated patients.

BACKGROUND: Intravenous (IV) Alteplase (tissue plasminogen activator [t-PA]) improves outcome in patients with acute ischemic stroke. Of those with full recovery, some may not have had ischemia. We analyzed the frequency and post-treatment outcomes of stroke code patients with no imaging evidence of stroke to establish the incidence of neuroimaging negative cerebral ischemia (NNCI) and stroke mimics treated with t-PA. In addition, we compared these patients with the group of stroke patients with imaging evidence of acute stroke to determine whether there was a difference in adverse events and functional outcomes. METHODS: We included all adult stroke patients treated with IV t-PA within 3 hours of stroke onset from the University of California, San Diego, Specialized Programs of Translational Research in Acute Stroke database through January 2013. The imaging positive stroke (IPS) code group comprised patients with neuroimaging evidence of acute ischemic stroke, whereas the imaging negative stroke code (INS) group included those patients without neuroimaging evidence of acute cerebral ischemia. All final diagnoses were reviewed by an adjudicating body. We reviewed medical records and neuroimaging; compared discharge diagnosis, 90-day modified Rankin Scale (mRS) score, and incidence of intracranial hemorrhage; and adjusted for age, admission National Institutes of Health Stroke Scale (NIHSS), prestroke mRS, and diabetes in multivariable models. RESULTS: We identified 106 patients, 74 IPS patients and 32 INS patients, who had similar baseline characteristics, except for baseline NIHSS (IPS 12.9 ± 8.2, INS 8.0 ± 5.6, P = .002) and incidence of cardiac arrhythmias (IPS 32.4%, INS 12.5%, P = .034). The diagnoses in the INS group were stroke (23, 72%)-representing NNCI, somatization (6, 19%), tumor (1, 3%), seizure (1, 3%), and migraine (1, 3%). All IPS patients were diagnosed with acute ischemic stroke. Adjusted for age, baseline NIHSS, prestroke mRS, and diabetes, the INS patients had significantly higher rates (odds ratio 3.04, P = .036) of good functional outcome (90-day mRS score 0-1). Intracerebral hemorrhage (ICH) was found in 24% of the IPS patients and was symptomatic in 6.8%. None of the INS patients had ICH. CONCLUSIONS: Because most INS patients were found to have NNCI, which may represent either transient ischemic attack or aborted stroke, and there were no intracerebral hemorrhages in the INS group, our data support the safety of administering IV t-PA to all patients in whom acute ischemic stroke is clinically suspected. We have demonstrated that NNCI patients and stroke mimics are common, and future larger scale prospective studies are required to delineate the true frequencies of each and to evaluate differences in outcomes.

Reduced clopidogrel metabolism in a multiethnic population: prevalence and rates of recurrent cerebrovascular events.

BACKGROUND: Concern has recently been raised over the possibility of a reduced efficacy of clopidogrel because of genetic variations in cytochrome P450, family 2, subfamily C, polypeptide 19 (CYP2C19) metabolism. A black box warning from the US Food and Drug Administration recommends that all patients be tested. It has been estimated that approximately 3% (range 2-14%) of the population are poor metabolizers, but few data are available for cerebrovascular patients. The objective of this study is to evaluate the frequency and effects of variability in CYP2C19 metabolism in patients with cerebrovascular disease. METHODS: A retrospective review of all patients with stroke and transient ischemic attack (TIA) tested for the clopidogrel CYP2C19 genotype was performed, with a collection of data including race/ethnicity, CYP2C19 status, and the presence of recurrent vascular events. RESULTS: A total of 53 cerebrovascular patients were tested, consisting of 5.7% poor (n = 3), 26.4% intermediate (n = 14), 62.3% extensive (n = 33), 3.8% indeterminate (n = 2), and 1.9% "mixed ultra rapid and poor" (n = 1) metabolizers. Only 10 of 38 white patients (26.3%; 95% confidence interval [CI] 0.14-0.42) were intermediate or poor metabolizers, compared with 7 of 15 (46.7%; 95% CI 0.25-0.70) nonwhites. Of 43 patients treated with clopidogrel, 3 of 27 extensive metabolizers (11.1%; 95% CI 0.04-0.28) had recurrent cerebrovascular events compared with 33.3% of intermediate metabolizers (4/12; 95% CI 0.14-0.61) and 50% of poor metabolizers (1/2; 95% CI 0.09-0.90). CONCLUSIONS: These data suggest that the proportion of poor/intermediate clopidogrel metabolizers in cerebrovascular patients is comparable to cardiovascular studies and these patients may have an increased risk of recurrent cerebrovascular events. Routine CYP2C19 testing may be warranted.