Projections of Endovascular Therapy-Eligible Patients With Stroke for the US Population.

BACKGROUND: As stroke endovascular thrombectomy (EVT) treatment indications expand, understanding population-based EVT eligibility becomes critical for resource planning. We aimed to project current and future population-based EVT eligibility in the United States. METHODS: We conducted a post hoc analysis of the physician-adjudicated GCNKSS (Greater Cincinnati Northern Kentucky Stroke Study; 2015 epoch), a population-based, cross sectional, observational study of stroke incidence, treatment, and outcomes across a 5-county region. All hospitalized patients ≥18 years of age with acute ischemic stroke were ascertained using the International Classification of Diseases, Ninth Revision codes 430-436 and Tenth Revision codes I60-I67 and G45-G46 and extrapolated to the US adult census 2020. We determined the rate of EVT eligibility within the GCNKSS population using time from last known well to presentation (0-5 versus 5-23 hours), presenting National Institutes of Health Stroke Scale, and prestroke modified Rankin Scale. Both conservative and liberal estimates of prevalence of large vessel occlusion and large core were then applied based on literature review (unavailable within the 2015 GCNKSS). This eligibility was then extrapolated to the 2020 US population. RESULTS: Of the 1 057 183 adults within GCNKSS in 2015, 2741 had an ischemic stroke and 2176 had data available for analysis. We calculated that 8659 to 17 219 patients (conservative to liberal) meet the current guideline-recommended EVT criteria (nonlarge core, no prestroke disability, and National Institutes of Health Stroke Scale score ≥6) in the United States. Estimates (conservative to liberal) for expanded EVT eligibility subpopulations include (1) 5316 to 10 635 by large core; (2) 10 635 to 21 270 by mild presenting deficits with low National Institutes of Health Stroke Scale score; (3) 13 572 to 27 089 by higher prestroke disability; and (4) 7039 to 14 180 by >1 criteria. These expanded eligibility subpopulations amount to 36 562 to 73 174 patients. CONCLUSIONS: An estimated 8659 to 17 219 adult patients in the United States met strict EVT eligibility criteria in 2020. A 4-fold increase in population-based EVT eligibility can be anticipated with incremental adoption of recent or future positive trials. US stroke systems need to be rapidly optimized to handle all EVT-eligible patients with stroke.

Apixaban to Prevent Recurrence After Cryptogenic Stroke in Patients With Atrial Cardiopathy: The ARCADIA Randomized Clinical Trial.

Importance: Atrial cardiopathy is associated with stroke in the absence of clinically apparent atrial fibrillation. It is unknown whether anticoagulation, which has proven benefit in atrial fibrillation, prevents stroke in patients with atrial cardiopathy and no atrial fibrillation. Objective: To compare anticoagulation vs antiplatelet therapy for secondary stroke prevention in patients with cryptogenic stroke and evidence of atrial cardiopathy. Design, Setting, and Participants: Multicenter, double-blind, phase 3 randomized clinical trial of 1015 participants with cryptogenic stroke and evidence of atrial cardiopathy, defined as P-wave terminal force greater than 5000 µV × ms in electrocardiogram lead V1, serum N-terminal pro-B-type natriuretic peptide level greater than 250 pg/mL, or left atrial diameter index of 3 cm/m2 or greater on echocardiogram. Participants had no evidence of atrial fibrillation at the time of randomization. Enrollment and follow-up occurred from February 1, 2018, through February 28, 2023, at 185 sites in the National Institutes of Health StrokeNet and the Canadian Stroke Consortium. Interventions: Apixaban, 5 mg or 2.5 mg, twice daily (n = 507) vs aspirin, 81 mg, once daily (n = 508). Main Outcomes and Measures: The primary efficacy outcome in a time-to-event analysis was recurrent stroke. All participants, including those diagnosed with atrial fibrillation after randomization, were analyzed according to the groups to which they were randomized. The primary safety outcomes were symptomatic intracranial hemorrhage and other major hemorrhage. Results: With 1015 of the target 1100 participants enrolled and mean follow-up of 1.8 years, the trial was stopped for futility after a planned interim analysis. The mean (SD) age of participants was 68.0 (11.0) years, 54.3% were female, and 87.5% completed the full duration of follow-up. Recurrent stroke occurred in 40 patients in the apixaban group (annualized rate, 4.4%) and 40 patients in the aspirin group (annualized rate, 4.4%) (hazard ratio, 1.00 [95% CI, 0.64-1.55]). Symptomatic intracranial hemorrhage occurred in 0 patients taking apixaban and 7 patients taking aspirin (annualized rate, 1.1%). Other major hemorrhages occurred in 5 patients taking apixaban (annualized rate, 0.7%) and 5 patients taking aspirin (annualized rate, 0.8%) (hazard ratio, 1.02 [95% CI, 0.29-3.52]). Conclusions and Relevance: In patients with cryptogenic stroke and evidence of atrial cardiopathy without atrial fibrillation, apixaban did not significantly reduce recurrent stroke risk compared with aspirin. Trial Registration: ClinicalTrials.gov Identifier: NCT03192215.

Using Epidemiological Data to Inform Clinical Trial Feasibility Assessments: A Case Study.

BACKGROUND: Clinical trial enrollment and completion is challenging, with nearly half of all trials not being completed or not completed on time. In 2014, the National Institutes of Health StrokeNet in collaboration with stroke epidemiologists from GCNKSS (Greater Cincinnati/Northern Kentucky Stroke Study) began providing proposed clinical trials with formal trial feasibility assessments. Herein, we describe the process of prospective feasibility analyses using epidemiological data that can be used to improve enrollment and increase the likelihood a trial is completed. METHODS: In 2014, DEFUSE 3 (Endovascular Therapy Following Imaging Evaluation for Ischemic Stroke 3) trialists, National Institutes of Health StrokeNet, and stroke epidemiologists from GCNKSS collaborated to evaluate the initial inclusion/exclusion criteria for the DEFUSE 3 study. Trial criteria were discussed and an assessment was completed to evaluate the percent of the stroke population that might be eligible for the study. The DEFUSE 3 trial was stopped early with the publication of DAWN (Thrombectomy 6 to 24 Hours After Stroke With a Mismatch Between Deficit and Infarct), and the Wilcoxon rank-sum statistic was used to analyze whether the trial would have been stopped had the proposed changes not been made, following the DEFUSE 3 statistical analysis plan. RESULTS: After initial epidemiological analysis, 2.4% of patients with acute stroke in the GCNKSS population would have been predicted to be eligible for the study. After discussion with primary investigators and modifying 4 key exclusion criteria (upper limit of age increased to 90 years, baseline modified Rankin Scale broadened to 0-2, time since last well expanded to 16 hours, and decreased lower limit of National Institutes of Health Stroke Scale score to <6), the number predicted to be eligible for the trial increased to 4%. At the time of trial conclusion, 57% of the enrolled patients qualified only by the modified criteria, and the trial was stopped at an interim analysis that demonstrated efficacy. We estimated that the Wilcoxon rank-sum value for the unadjusted predicted enrollment would not have crossed the threshold for efficacy and the trial not stopped. CONCLUSIONS: Objectively assessing trial inclusion/exclusion criteria using a population-based resource in a collaborative and iterative process including epidemiologists can lead to improved recruitment and can increase the likelihood of successful trial completion.

Systematic Review of Sex Differences in Ischemic Strokes Among Young Adults: Are Young Women Disproportionately at Risk?

BACKGROUND AND PURPOSE: Recent evidence suggests that young women (18-45 years) may be at higher risk of ischemic strokes than men of the same age. The goal of this systematic review is to reconcile and synthesize existing evidence of sex differences among young adults with ischemic strokes. METHODS: We searched PubMed from January 2008 to July 2021 for relevant articles and reviews and consulted their references. We included original studies that (1) were population based and (2) reported stroke incidence by sex or sex-specific incidence rate ratios of young adults ≤45 years. We excluded studies that (1) omitted measurements of error for incidence rates or incidence rate ratios, (2) omitted age adjustment, and (3) were not in English. Statistical synthesis was performed to estimate sex difference by age group (≤35, 35-45, and ≤45) and stroke type. RESULTS: We found 19 studies that reported on sex-specific stroke incidence among young adults, including 3 that reported on overlapping data. Nine studies did not find a statistically significant sex difference among young adults ≤45 years. Three studies found higher rates of ischemic stroke among men among young adults ≥30 to 35 years. Four studies found more women with ischemic strokes among young adults ≤35 years. Overall, in young adults ≤35 years, the estimated effect size favored more ischemic strokes in women (incidence rate ratio, 1.44 [1.18-1.76], I2=82%) and a nonsignificant sex difference in young adults 35 to 45 years (incidence rate ratio, 1.08 [0.85-1.38], I2=95%). CONCLUSIONS: Overall, there were 44% more women ≤35 years with ischemic strokes than men. This gap narrows in young adults, 35 to 45 years, and there is conflicting evidence whether more men or women have ischemic strokes in the 35 to 45 age group.

Substance Use and Performance of Toxicology Screens in the Greater Cincinnati Northern Kentucky Stroke Study.

BACKGROUND: Though stroke risk factors such as substance use may vary with age, less is known about trends in substance use over time or about performance of toxicology screens in young adults with stroke. METHODS: Using the Greater Cincinnati Northern Kentucky Stroke Study, a population-based study in a 5-county region comprising 1.3 million people, we reported the frequency of documented substance use (cocaine/marijuana/opiates/other) obtained from electronic medical record review, overall and by race/gender subgroups among physician-adjudicated stroke events (ischemic and hemorrhagic) in adults 20 to 54 years of age. Secondary analyses included heavy alcohol use and cigarette smoking. Data were reported for 5 one-year periods spanning 22 years (1993/1994-2015), and trends over time were tested. For 2015, to evaluate factors associated with performance of toxicology screens, multiple logistic regression was performed. RESULTS: Overall, 2152 strokes were included: 74.5% were ischemic, mean age was 45.7±7.6, 50.0% were women, and 35.9% were Black. Substance use was documented in 4.4%, 10.4%, 19.2%, 24.0%, and 28.8% of cases in 1993/1994, 1999, 2005, 2010, and 2015, respectively (Ptrend<0.001). Between 1993/1994 and 2015, documented substance use increased in all demographic subgroups. Adjusting for gender, comorbidities, and National Institutes of Health Stroke Scale, predictors of toxicology screens included Black race (adjusted odds ratio, 1.58 [95% CI, 1.02-2.45]), younger age (adjusted odds ratio, 0.70 [95% CI, 0.53-0.91], per 10 years), current smoking (adjusted odds ratio, 1.62 [95% CI, 1.06-2.46]), and treatment at an academic hospital (adjusted odds ratio, 1.80 [95% CI, 1.14-2.84]). After adding chart-reported substance use to the model, only chart-reported substance abuse and age were significant. CONCLUSIONS: In a population-based study of young adults with stroke, documented substance use increased over time, and documentation of substance use was higher among Black compared with White individuals. Further work is needed to confirm race-based disparities and trends in substance use given the potential for bias in screening and documentation. Findings suggest a need for more standardized toxicology screening.

Forty-Year Shifting Distribution of Systolic Blood Pressure With Population Hypertension Treatment and Control.

BACKGROUND: Hypertension awareness, treatment, and control programs were initiated in the United States during the 1960s and 1970s. Whereas blood pressure (BP) control in the population and subsequent reduced hypertension-related disease risks have improved since the implementation of these interventions, it is unclear whether these BP changes can be generalized to diverse and high-risk populations. This report describes the 4-decade change in BP levels for the population in a high disease risk southeastern region of the United States. The objective is to determine the magnitude of the shift in systolic BP (SBP) among Blacks and Whites from the Southeast between 1960 and 2005 with the assessment of the unique population cohorts. METHODS: A multicohort study design compared BPs from the CHS (Charleston Heart Study) and ECHS (Evans County Heart Study) in 1960 and the REGARDS study (Reasons for Geographic and Racial Differences in Stroke) 4 decades later. The analyses included participants ≥45 years of age from CHS (n=1323), ECHS (n=1842), and REGARDS (n=6294) with the main outcome of SBP distribution. RESULTS: Among Whites 45 to 54 years of age, the median SBP was 18 mm Hg (95% CI, 16-21 mm Hg) lower in 2005 than 1960. The median shift was a 45 mm Hg (95% CI, 37-51 mm Hg) decline for those ≥75 years of age. The shift was larger for Blacks, with median declines of 38 mm Hg (95% CI, 32-40 mm Hg) at 45 to 54 years of age and 50 mm Hg (95% CI, 33-60 mm Hg) for ages ≥75 years. The 95th percentile of SBP decreased 60 mm Hg for Whites and 70 mm Hg for Blacks. CONCLUSIONS: The results of the current analyses of the unique cohorts in the Southeast confirm the improvements in population SBP levels since 1960. This assessment provides new evidence of improvement in SBP, suggesting that strategies and programs implemented to improve hypertension treatment and control have been extraordinarily successful for both Blacks and Whites residing in a high-risk region of the United States. Severe BP elevations commonly observed in the 1960s have been nearly eliminated, with the current 75th percentile of BP generally less than the 25th percentile of BP in 1960.

Time Course for Benefit and Risk of Clopidogrel and Aspirin After Acute Transient Ischemic Attack and Minor Ischemic Stroke.

BACKGROUND: In patients with acute minor ischemic stroke or high-risk transient ischemic attack enrolled in the POINT trial (Platelet-Oriented Inhibition in New TIA and Minor Ischemic Stroke [POINT] Trial), the combination of clopidogrel and aspirin for 90 days reduced major ischemic events but increased major hemorrhage in comparison to aspirin alone. METHODS: In a secondary analysis of POINT (N=4881), we assessed the time course for benefit and risk from the combination of clopidogrel and aspirin. The primary efficacy outcome was a composite of ischemic stroke, myocardial infarction, or ischemic vascular death. The primary safety outcome was major hemorrhage. Risks and benefits were estimated for delayed times of treatment initiation using left-truncated models. RESULTS: Through 90 days, the rate of major ischemic events was initially high then decreased markedly, whereas the rate of major hemorrhage remained low but relatively constant throughout. With the use of a model-based approach, the optimal change point for major ischemic events was 21 days (0-21 days hazard ratio 0.65 for clopidogrel-aspirin versus aspirin; 95% CI, 0.50-0.85; P=0.0015, in comparison to 22-90 days hazard ratio, 1.38; 95% CI, 0.81-2.35; P=0.24). Models showed benefits of clopidogrel-aspirin for treatment delayed as long as 3 days after symptom onset. CONCLUSIONS: The benefit of clopidogrel-aspirin occurs predominantly within the first 21 days, and outweighs the low, but ongoing risk of major hemorrhage. When considered with the results of the CHANCE trial (Clopidogrel in High-Risk Patients With Non-disabling Cerebrovascular Events), a similar trial treating with clopidogrel-aspirin for 21 days and showing no increase in major hemorrhage, these results suggest that limiting clopidogrel-aspirin use to 21 days may maximize benefit and reduce risk after high-risk transient ischemic attack or minor ischemic stroke. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov. Unique identifier: NCT00991029.

Ischemic Stroke and Bleeding: Clinical Benefit of Anticoagulation in Atrial Fibrillation After Intracerebral Hemorrhage.

Background and Purpose- Patients with intracerebral hemorrhage (ICH) and atrial fibrillation (AF) are at risk for ischemic events. While risk calculators (CHA2DS2-VASc and HAS-BLED) have been validated to assess risk for ischemic stroke and major bleeding in AF patients, decisions about anticoagulation must consider the net clinical benefit of anticoagulation. Furthermore, stroke and bleeding risk are highly correlated, making decisions more difficult. Methods- We examined patients in the GERFHS III study (Genetic and Environmental Risk Factors for Hemorrhagic Stroke)-a population-based retrospective study of spontaneous ICH patients without a structural or traumatic cause in the Greater Cincinnati/Northern Kentucky region between July 2008 and December 2012. CHA2DS2-VASc and HAS-B(L)ED (minus L because labile international normalized ratio was unavailable) scores were calculated for ICH patients with AF. Using a Markov state transition model, we estimated net clinical benefit of anticoagulation relative to no treatment in quality-adjusted life years (QALYs). We defined minimal clinically relevant benefit as 0.1 QALYs. Results- Among 1186 cases of spontaneous ICH, 95 cases had AF and met our survival criteria. Within 1 year, 8 of 95 (8%) would be expected to have a major bleeding event on anticoagulation, and 5 of 95 (5%) of patients would be expected to have an ischemic stroke off anticoagulation. Sixty-eight of 95 (71%) patients would have higher risk for major bleeding than for ischemic stroke. Anticoagulation with directly acting anticoagulants would result in no clinically significant gain or loss in 73%. Roughly 12% would gain >0.1 QALYs, and 15% would lose >0.1 QALYs. Among patients receiving aspirin, most have no significant net clinical benefit or loss. Overall, anticoagulation of the entire cohort would result in an aggregate loss of 0.92 QALYs. Conclusions- Our analysis suggests that universal anticoagulation after ICH would be associated with a net loss of QALY. Additional factors should be considered before anticoagulating patients with AF after ICH. Registration- URL: https://www.clinicaltrials.gov. Unique identifier: NCT00930280.

Temporal Trends in Stroke Incidence Over Time by Sex and Age in the GCNKSS.

Background and Purpose- Sex differences in stroke incidence over time were previously reported from the GCNKSS (Greater Cincinnati/Northern Kentucky Stroke Study). We aimed to determine whether these differences continued through 2015 and whether they were driven by particular age groups. Methods- Within the GCNKSS population of 1.3 million, incident (first ever) strokes among residents ≥20 years of age were ascertained at all local hospitals during 5 periods: July 1993 to June 1994 and calendar years 1999, 2005, 2010, and 2015. Out-of-hospital cases were sampled. Sex-specific incidence rates per 100 000 were adjusted for age and race and standardized to the 2010 US Census. Trends over time by sex were compared (overall and age stratified). Sex-specific case fatality rates were also reported. Bonferroni corrections were applied for multiple comparisons. Results- Over the 5 study periods, there were 9733 incident strokes (56.3% women). For women, there were 229 (95% CI, 215-242) per 100 000 incident strokes in 1993/1994 and 174 (95% CI, 163-185) in 2015 (P<0.05), compared with 282 (95% CI, 263-301) in 1993/1994 to 211 (95% CI, 198-225) in 2015 (P<0.05) in men. Incidence rates decreased between the first and last study periods in both sexes for IS but not for intracerebral hemorrhage or subarachnoid hemorrhage. Significant decreases in stroke incidence occurred between the first and last study periods for both sexes in the 65- to 84-year age group and men only in the ≥85-year age group; stroke incidence increased for men only in the 20- to 44-year age group. Conclusions- Overall stroke incidence decreased from the early 1990s to 2015 for both sexes. Future studies should continue close surveillance of sex differences in the 20- to 44-year and ≥85-year age groups, and future stroke prevention strategies should target strokes in the young- and middle-age groups, as well as intracerebral hemorrhage.

Prehospital neurological deterioration in stroke.

BACKGROUND AND PURPOSE: Patients with stroke can experience neurological deterioration in the prehospital setting. We evaluated patients with stroke to determine factors associated with prehospital neurological deterioration (PND). METHODS: Among the Greater Cincinnati/Northern Kentucky region (population ~1.3 million), we screened all 15 local hospitals' admissions from 2010 for acute stroke and included patients aged ≥20. The GCS was compared between emergency medical services (EMS) arrival and hospital arrival, with decrease ≥2 points considered PND. Data obtained retrospectively included demographics, medical history and medication use, stroke subtype (eg, ischaemic stroke (IS), intracerebral haemorrhage (ICH), subarachnoid haemorrhage (SAH)) and IS subtype (eg, small vessel, large vessel, cardioembolic), seizure at onset, time intervals between symptom onset, EMS arrival and hospital arrival, EMS level of training, and blood pressure and serum glucose on EMS arrival. RESULTS: Of 2708 total patients who had a stroke, 1092 patients (median (IQR) age 74 (61-83) years; 56% women; 21% black) were analysed. PND occurred in 129 cases (12%), including 9% of IS, 24% of ICH and 16% of SAH. In multivariable analysis, black race, atrial fibrillation, haemorrhagic subtype and ALS level of transport were associated with PND. CONCLUSION: Haemorrhage and atrial fibrillation is associated with PND in stroke, and further investigation is needed to establish whether PND can be predicted. Further studies are also needed to assess whether preferential transport of patients with deterioration to hospitals equipped with higher levels of care is beneficial, identify why race is associated with deterioration and to test therapies targeting PND.

Effect of Alteplase vs Aspirin on Functional Outcome for Patients With Acute Ischemic Stroke and Minor Nondisabling Neurologic Deficits: The PRISMS Randomized Clinical Trial.

Importance: More than half of patients with acute ischemic stroke have minor neurologic deficits (National Institutes of Health Stroke Scale [NIHSS] score of 0-5) at presentation. Although prior major trials of alteplase included patients with low NIHSS scores, few without clearly disabling deficits were enrolled. Objective: To evaluate the efficacy and safety of alteplase in patients with NIHSS scores of 0 to 5 whose deficits are not clearly disabling. Design, Setting, and Participants: The PRISMS trial was designed as a 948-patient, phase 3b, double-blind, double-placebo, multicenter randomized clinical trial of alteplase compared with aspirin for emergent stroke at 75 stroke hospital networks in the United States. Patients with acute ischemic stroke whose deficits were scored as 0 to 5 on the NIHSS and judged not clearly disabling and in whom study treatment could be initiated within 3 hours of onset were eligible and enrolled from May 30, 2014, to December 20, 2016, with final follow-up on March 22, 2017. Interventions: Participants were randomized to receive intravenous alteplase at the standard dose (0.9 mg/kg) with oral placebo (n = 156) or oral aspirin, 325 mg, with intravenous placebo (n = 157). Main Outcomes and Measures: The primary outcome was the difference in favorable functional outcome, defined as a modified Rankin Scale score of 0 or 1 at 90 days via Cochran-Mantel-Haenszel test stratified by pretreatment NIHSS score, age, and time from onset to treatment. Because of early termination of the trial, prior to unblinding or interim analyses, the plan was revised to examine the risk difference of the primary outcome by a linear model adjusted for the same factors. The primary safety end point was symptomatic intracranial hemorrhage (sICH) within 36 hours of intravenous study treatment. Results: Among 313 patients enrolled at 53 stroke networks (mean age, 62 [SD, 13] years; 144 [46%] women; median NIHSS score, 2 [interquartile range {IQR}, 1-3]; median time to treatment, 2.7 hours [IQR, 2.1-2.9]), 281 (89.8%) completed the trial. At 90 days, 122 patients (78.2%) in the alteplase group vs 128 (81.5%) in the aspirin group achieved a favorable outcome (adjusted risk difference, -1.1%; 95% CI, -9.4% to 7.3%). Five alteplase-treated patients (3.2%) vs 0 aspirin-treated patients had sICH (risk difference, 3.3%; 95% CI, 0.8%-7.4%). Conclusions and Relevance: Among patients with minor nondisabling acute ischemic stroke, treatment with alteplase vs aspirin did not increase the likelihood of favorable functional outcome at 90 days. However, the very early study termination precludes any definitive conclusions, and additional research may be warranted. Trial Registration: ClinicalTrials.gov Identifier: NCT02072226.

Self-Reported Stroke Risk Stratification: Reasons for Geographic and Racial Differences in Stroke Study.

BACKGROUND AND PURPOSE: The standard for stroke risk stratification is the Framingham Stroke Risk Function (FSRF), an equation requiring an examination for blood pressure assessment, venipuncture for glucose assessment, and ECG to determine atrial fibrillation and heart disease. We assess a self-reported stroke risk function (SRSRF) to stratify stroke risk in comparison to the FSRF. METHODS: Participants from the REGARDS study (Reasons for Geographic and Racial Differences in Stroke) were evaluated at baseline and followed for incident stroke. The FSRF was calculated using directly assessed stroke risk factors. The SRSRF was calculated from 13 self-reported questions to exclude those with prevalent stroke and assess stroke risk. Proportional hazards analysis was used to assess incident stroke risk using the FSRF and SRSRF. RESULTS: Over an average 8.2-year follow-up, 939 of 23 983 participants had a stroke. The FSRF and SRSRF produced highly correlated risk scores (rSpearman=0.852; 95% confidence interval, 0.849-0.856); however, the SRSRF had higher discrimination of stroke risk than the FSRF (cSRSRF=0.7266; 95% confidence interval, 0.7076-0.7457; cFSRF=0.7075; 95% confidence interval, 0.6877-0.7273; P=0.0038). The 10-year stroke risk in the highest decile of predicted risk was 11.1% for the FSRF and 13.4% for the SRSRF. CONCLUSIONS: A simple self-reported questionnaire can be used to identify those at high risk for stroke better than the gold standard FSRF. This instrument can be used clinically to easily identify individuals at high risk for stroke and also scientifically to identify a subpopulation enriched for stroke risk.

Contributors to the Excess Stroke Mortality in Rural Areas in the United States.

BACKGROUND AND PURPOSE: Stroke mortality is 30% higher in the rural United States. This could be because of either higher incidence or higher case fatality from stroke in rural areas. METHODS: The urban-rural status of 23 280 stroke-free participants recruited between 2003 and 2007 in the REGARDS study (Reasons for Geographic and Racial Differences in Stroke) was classified using the Rural-Urban Commuting Area scheme as residing in urban, large rural town/city, or small rural town or isolated areas. The risk of incident stroke was assessed using proportional hazards analysis, and case fatality (death within 30 days of stroke) was assessed using logistic regression. Models were adjusted for demographics, traditional stroke risk factors, and measures of socioeconomic status. RESULTS: After adjustment for demographic factors and relative to urban areas, stroke incidence was 1.23-times higher (95% confidence intervals, 1.01-1.51) in large rural town/cities and 1.30-times higher (95% confidence intervals, 1.03-1.62) in small rural towns or isolated areas. Adjustment for risk factors and socioeconomic status only modestly attenuated this association, and the association became marginally nonsignificant (P=0.071). There was no association of rural-urban status with case fatality (P>0.47). CONCLUSIONS: The higher stroke mortality in rural regions seemed to be attributable to higher stroke incidence rather than case fatality. A higher prevalence of risk factors and lower socioeconomic status only modestly contributed to the increased risk of incident stroke risk in rural areas. There was no evidence of higher case fatality in rural areas.

Association Between Acute Kidney Disease and Intravenous Dye Administration in Patients With Acute Stroke: A Population-Based Study.

BACKGROUND AND PURPOSE: Computed tomographic angiography and conventional angiography provide timely vascular anatomic information in patients with stroke. However, iodinated contrast dye may cause acute kidney injury (AKI). Within a large, biracial population, we examined in-hospital incidence of new or worsening kidney disease in patients with stroke and its association with administration of intravenous dye. METHODS: All adult residents of the Greater Cincinnati/Northern Kentucky region with acute ischemic stroke or intracerebral hemorrhage who presented to an emergency department in 2010 were included. Prevalence of unsuspected kidney disease at the time of emergency department presentation and the incidence of AKI after admission in 2 groups of patients-those who did and those who did not receive intravenous dye-were determined. RESULTS: In 2010, 2299 patients met inclusion criteria (89% ischemic stroke and 11% intracerebral hemorrhage); mean age 69 years (SD 15), 22% black, and 54% women. Among these patients, 37% had kidney disease at baseline, including 22% (516/2299) in whom this was unsuspected. Two percent (2%; 15/853) of patients with baseline kidney disease developed AKI during the hospital stay. Of those with no baseline kidney disease, 1% (14/14 467) developed AKI. There was no association between dye administration and new or worsening kidney disease. CONCLUSIONS: Although 22% of patients in the Greater Cincinnati/Northern Kentucky stroke population had unsuspected kidney disease, the incidence of new or worsening kidney disease was low, and AKI was not associated with dye administration. These findings confirm single-center reports that the risk of severe renal complications after contrast dye is small.

Prevalence of Positive Troponin and Echocardiogram Findings and Association With Mortality in Acute Ischemic Stroke.

BACKGROUND AND PURPOSE: Acute ischemic stroke (AIS) patients may have raised serum cardiac troponin levels on admission, although it is unclear what prognostic implications this has, and whether elevated levels are associated with cardiac causes of stroke or structural cardiac disease as seen on echocardiogram. We investigated the positivity of cardiac troponin and echocardiogram testing within a large biracial AIS population and any association with poststroke mortality. METHODS: Within a catchment area of 1.3 million, we screened emergency department admissions from 2010 using International Classification of Diseases, Ninth Edition, discharge codes 430 to 436 and ascertained all physician-confirmed AIS cases by retrospective chart review. Hypertroponinemia was defined as elevation in cardiac troponin above the standard 99th percentile. Multiple logistic regression was performed, controlling for stroke severity, history of cardiac disease, and all other stroke risk factors. RESULTS: Of 1999 AIS cases, 1706 (85.3%) had a cardiac troponin drawn and 1590 (79.5%) had echocardiograms. Hypertroponinemia occurred in 353 of 1706 (20.7%) and 160 of 1590 (10.1%) had echocardiogram findings of interest. Among 1377 who had both tests performed, hypertroponinemia was independently associated with echocardiogram findings (odds ratio, 2.9; 95% confidence interval, 2-4.2). When concurrent myocardial infarctions (3.5%) were excluded, hypertroponinemia was also associated with increased mortality at 1 year (35%; odds ratio, 3.45; 95% confidence interval, 2.1-5.6) and 3 years (60%; odds ratio, 2.91; 95% confidence interval, 2.06-4.11). CONCLUSIONS: Hypertroponinemia in the context of AIS without concurrent myocardial infarction was associated with structural cardiac disease and long-term mortality. Prospective studies are needed to determine whether further cardiac evaluation might improve the long-term mortality rates seen in this group.

Estimated Impact of Emergency Medical Service Triage of Stroke Patients on Comprehensive Stroke Centers: An Urban Population-Based Study.

BACKGROUND AND PURPOSE: The American Stroke Association recommends that Emergency Medical Service bypass acute stroke-ready hospital (ASRH)/primary stroke center (PSC) for comprehensive stroke centers (CSCs) when transporting appropriate stroke patients, if the additional travel time is ≤15 minutes. However, data on additional transport time and the effect on hospital census remain unknown. METHODS: Stroke patients ≥20 years old who were transported from home to an ASRH/PSC or CSC via Emergency Medical Service in 2010 were identified in the Greater Cincinnati area population of 1.3 million. Addresses of all patients' residences and hospitals were geocoded, and estimated travel times were calculated. We estimated the mean differences between the travel time for patients taken to an ASRH/PSC and the theoretical time had they been transported directly to the region's CSC. RESULTS: Of 929 patients with geocoded addresses, 806 were transported via Emergency Medical Service directly to an ASRH/PSC. Mean additional travel time of direct transport to the CSC, compared with transport to an ASRH/PSC, was 7.9±6.8 minutes; 85% would have ≤15 minutes added transport time. Triage of all stroke patients to the CSC would have added 727 patients to the CSC's census in 2010. Limiting triage to the CSC to patients with National Institutes of Health Stroke Scale score of ≥10 within 6 hours of onset would have added 116 patients (2.2 per week) to the CSC's annual census. CONCLUSIONS: Emergency Medical Service triage to CSCs based on stroke severity and symptom duration may be feasible. The impact on stroke systems of care and patient outcomes remains to be determined and requires prospective evaluation.

Meta-analysis of genome-wide association studies identifies 1q22 as a susceptibility locus for intracerebral hemorrhage.

Intracerebral hemorrhage (ICH) is the stroke subtype with the worst prognosis and has no established acute treatment. ICH is classified as lobar or nonlobar based on the location of ruptured blood vessels within the brain. These different locations also signal different underlying vascular pathologies. Heritability estimates indicate a substantial genetic contribution to risk of ICH in both locations. We report a genome-wide association study of this condition that meta-analyzed data from six studies that enrolled individuals of European ancestry. Case subjects were ascertained by neurologists blinded to genotype data and classified as lobar or nonlobar based on brain computed tomography. ICH-free control subjects were sampled from ambulatory clinics or random digit dialing. Replication of signals identified in the discovery cohort with p < 1 × 10(-6) was pursued in an independent multiethnic sample utilizing both direct and genome-wide genotyping. The discovery phase included a case cohort of 1,545 individuals (664 lobar and 881 nonlobar cases) and a control cohort of 1,481 individuals and identified two susceptibility loci: for lobar ICH, chromosomal region 12q21.1 (rs11179580, odds ratio [OR] = 1.56, p = 7.0 × 10(-8)); and for nonlobar ICH, chromosomal region 1q22 (rs2984613, OR = 1.44, p = 1.6 × 10(-8)). The replication included a case cohort of 1,681 individuals (484 lobar and 1,194 nonlobar cases) and a control cohort of 2,261 individuals and corroborated the association for 1q22 (p = 6.5 × 10(-4); meta-analysis p = 2.2 × 10(-10)) but not for 12q21.1 (p = 0.55; meta-analysis p = 2.6 × 10(-5)). These results demonstrate biological heterogeneity across ICH subtypes and highlight the importance of ascertaining ICH cases accordingly.

Where to Focus Efforts to Reduce the Black-White Disparity in Stroke Mortality: Incidence Versus Case Fatality?

BACKGROUND AND PURPOSE: At age 45 years, blacks have a stroke mortality ≈3× greater than their white counterparts, with a declining disparity at older ages. We assess whether this black-white disparity in stroke mortality is attributable to a black-white disparity in stroke incidence versus a disparity in case fatality. METHODS: We first assess if black-white differences in stroke mortality within 29 681 participants in the Reasons for Geographic and Racial Differences in Stroke (REGARDS) cohort reflect national black-white differences in stroke mortality and then assess the degree to which black-white differences in stroke incidence or 30-day case fatality after stroke contribute to the disparities in stroke mortality. RESULTS: The pattern of stroke mortality within the study mirrors the national pattern, with the black-to-white hazard ratio of ≈4.0 at age 45 years decreasing to ≈1.0 at age 85 years. The pattern of black-to-white disparities in stroke incidence shows a similar pattern but no evidence of a corresponding disparity in stroke case fatality. CONCLUSIONS: These findings show that the black-white differences in stroke mortality are largely driven by differences in stroke incidence, with case fatality playing at most a minor role. Therefore, to reduce the black-white disparity in stroke mortality, interventions need to focus on prevention of stroke in blacks.

Scientific Rationale for the Inclusion and Exclusion Criteria for Intravenous Alteplase in Acute Ischemic Stroke: A Statement for Healthcare Professionals From the American Heart Association/American Stroke Association.

PURPOSE: To critically review and evaluate the science behind individual eligibility criteria (indication/inclusion and contraindications/exclusion criteria) for intravenous recombinant tissue-type plasminogen activator (alteplase) treatment in acute ischemic stroke. This will allow us to better inform stroke providers of quantitative and qualitative risks associated with alteplase administration under selected commonly and uncommonly encountered clinical circumstances and to identify future research priorities concerning these eligibility criteria, which could potentially expand the safe and judicious use of alteplase and improve outcomes after stroke. METHODS: Writing group members were nominated by the committee chair on the basis of their previous work in relevant topic areas and were approved by the American Heart Association Stroke Council's Scientific Statement Oversight Committee and the American Heart Association's Manuscript Oversight Committee. The writers used systematic literature reviews, references to published clinical and epidemiology studies, morbidity and mortality reports, clinical and public health guidelines, authoritative statements, personal files, and expert opinion to summarize existing evidence and to indicate gaps in current knowledge and, when appropriate, formulated recommendations using standard American Heart Association criteria. All members of the writing group had the opportunity to comment on and approved the final version of this document. The document underwent extensive American Heart Association internal peer review, Stroke Council Leadership review, and Scientific Statements Oversight Committee review before consideration and approval by the American Heart Association Science Advisory and Coordinating Committee. RESULTS: After a review of the current literature, it was clearly evident that the levels of evidence supporting individual exclusion criteria for intravenous alteplase vary widely. Several exclusionary criteria have already undergone extensive scientific study such as the clear benefit of alteplase treatment in elderly stroke patients, those with severe stroke, those with diabetes mellitus and hyperglycemia, and those with minor early ischemic changes evident on computed tomography. Some exclusions such as recent intracranial surgery are likely based on common sense and sound judgment and are unlikely to ever be subjected to a randomized, clinical trial to evaluate safety. Most other contraindications or warnings range somewhere in between. However, the differential impact of each exclusion criterion varies not only with the evidence base behind it but also with the frequency of the exclusion within the stroke population, the probability of coexistence of multiple exclusion factors in a single patient, and the variation in practice among treating clinicians.