Abstract WP131: Radiation For Head And Neck Cancer And Risk Of Intracranial Hemorrhage

Introduction: Radiation therapy in head and neck cancers has previously been associated with cerebrovascular complications such as aneurysm formation, atherosclerosis, and ischemic stroke. Radiation is also associated with extradural cranial hemorrhagic complications due to weakening of vessel walls and labile hypertension from baroreflex failure. We hypothesized radiation therapy in head and neck cancers would also be associated with intracranial hemorrhage.

Methods: We performed a retrospective cohort study using inpatient and outpatient claims between 2008-2018 from a nationally representative 5% sample of Medicare beneficiaries. We included patients ≥65 years old with cancer of the oral cavity, nasal cavity, pharynx, or larynx, defined by ICD-9-CM and ICD-10-CM diagnosis codes, who underwent either radiation therapy or surgical tumor excision, defined by CPT codes. Intracranial hemorrhage was defined using ICD-9-CM and ICD-10-CM diagnosis codes for subarachnoid hemorrhage, intracerebral hemorrhage, and subdural hemorrhage. Cox proportional hazards regression was used to determine the association between radiation therapy and intracranial hemorrhage after adjustment for age, race, atrial fibrillation, coronary artery disease, hypertension, diabetes mellitus, congestive heart failure, chronic kidney disease, tobacco use, and alcohol use.

Results: Of 15,990 eligible patients, 5,316 (33%) underwent radiation therapy. A total of 568 (3.5%) patients had an intracranial hemorrhage. In unadjusted analysis, radiation therapy was associated with an increased risk of intracranial hemorrhage (HR, 1.72, 95% CI, 1.40-2.10). This association was present after adjustment for age, race, and vascular risk factors (HR, 1.29; 95% CI, 1.04-1.59).

Conclusions: In a nationally representative cohort of Medicare beneficiaries, radiation therapy for head and neck cancer was associated with an increased risk of intracranial hemorrhage.

Abstract 141: Atrial Cardiopathy And Left Ventricular Dysfunction In Patients With ESUS: Findings From The Arcadia Trial

Background: Recent data suggest biomarkers of atrial cardiopathy (ACP) can potentially identify a subset of patients with cryptogenic stroke who may benefit from anticoagulation. However, the specificity of these markers for atrial disease and their independence from measures of more global cardiac dysfunction remain unclear. We hypothesized that biomarkers of ACP collectively reflect left atrial pathology and are not strongly affected by coexisting left ventricular dysfunction.

Methods: ARCADIA is an ongoing multicenter trial comparing standard dose apixaban to aspirin therapy in patients with Embolic Stroke of Undetermined Source (ESUS) with ACP, defined as either N-terminal pro-brain natriuretic peptide [NT-proBNP] > 250 pg/mL; P wave terminal force velocity on ECG lead V1 [PTFV1] > 5000 μV*ms; or echocardiographic left atrial diameter index [LADI] ≥ 3 cm/m 2 . Pearson correlation coefficients and descriptive statistics were used to examine the relationship between left ventricular ejection fraction (LVEF) and ACP biomarkers.

Results: Among 2,616 ESUS patients screened, 1,046 met ≥ 1 ACP criterion (665 BNP, 531 PTFV1, 14 LADI). Patients with ACP were older (68 ± 11 vs 64 ± 10 years) and 54.5% were women. The great majority (84%) of subjects with ACP had normal LVEF (≥55%). Among them there was no correlation between LVEF and NT-proBNP (r= -0.01, P= 0.5) or PTFV1 (r=0.002, P=0.9). In patients with abnormal LVEF, there was a strong inverse correlation of LVEF with NT-proBNP (r=-0.4, P<0.001), but no correlation with PTFV1 (r=0.11, P=0.16). The LADI criterion was only met in a few patients, precluding further analyses. Among patients with NT-proBNP >250 pg/mL and measured LVEF (n=435), only 19% had abnormal LVEF. Compared to patients with abnormal NT-proBNP alone, those with both abnormal NT-proBNP and abnormal LVEF were younger (66.4 ± 11.0 vs. 71.6 ± 11.0, P<0.001), more often African American (29.6% vs. 11.5%, P<0.001), and more often male (56% vs. 40%, P=0.01).

Conclusion: Left ventricular dysfunction (EF ≤ 55%) is uncommon in patients with ACP as defined in ARCADIA. These findings suggest that, among patients with ESUS, atrial cardiopathy may represent a separate entity from LV dysfunction.

Abstract WP17: Impact Of Cigarette Smoking And Its Interaction With Hypertension And Diabetes On Cognitive Function

Introduction: We evaluated the association of a cigarette-smoking biomarker with cognitive function, and tested whether smoking acts synergistically with hypertension and diabetes to influence cognition.

Methods: We performed a cross-sectional analysis of nationally representative data from the US National Health and Nutrition Examination Survey. From 2011-2014, participants ≥60 years old were given 4 standardized cognitive tests by trained examiners: immediate word recall, delayed word recall, Animal Fluency Test (AFT), and Digit Symbol Substitution Test (DSST) - a multidomain cognitive test. Participants also had 3 consecutive standardized blood pressure measurements and hemoglobin A1c and serum cotinine tests, the latter an accurate biomarker of cigarette smoking/exposure. We used linear regression to evaluate the association of cotinine with cognitive performance. Where an association was found, interaction term testing evaluated effect modification by systolic blood pressure and hemoglobin A1c as continuous measures, and hypertension and diabetes as categorical variables. Models were adjusted for demographics, socioeconomic factors, education, cardiovascular risk factors/disease, alcohol use, and depression.

Results: The mean age of 3,244 participants was 69 years and 54% were women. Self-reported current smoking was present in 23%, 77% had hypertension, and 24% had diabetes. In adjusted linear regression models, higher serum cotinine levels were associated with worse performance on the DSST (β, -0.02; 95% CI, -0.03, -0.01; P=0.001), and non-significantly on the AFT (β, -0.003; 95% CI, -0.006, 0.0003; P=0.07), but not immediate or delayed recall. For the DSST, effect modification by systolic blood pressure (P=0.14) and hemoglobin A1c (P=0.39) was not observed. There was also no evidence of effect modification when testing interactions for hypertension and diabetes.

Conclusions: Higher levels of a smoking biomarker were associated with worse performance on a multidomain cognitive test at the population level, regardless of hypertension or diabetes. These data demonstrate the detrimental impact of smoking on cognition and underscore the broad importance of promoting smoking cessation to preserve cognitive health.

Abstract TMP13: Risk Stratification Models For Stroke In Patients Hospitalized With Covid-19 Infection: An American Heart Association Covid-19 CVD Registry Study

Introduction: Coronavirus Disease 2019 (COVID-19) is associated with an increased risk of stroke and worse stroke outcomes. A clinical score that can identify high-risk patients could enable closer monitoring and targeted preventative strategies.

Methods: We used data from the AHA’s COVID-19 CVD Registry to create a clinical score to predict the risk of stroke among patients hospitalized with COVID-19. We included patients aged >18 years who were hospitalized with COVID-19 at 122 centers from March 2020-March 2021. To build our score, we used demographics, preexisting comorbidities, home medications, and vital sign and lab values at admission. The outcome was a cerebrovascular event, defined as any ischemic or hemorrhagic stroke, TIA, or cerebral vein thrombosis. We used two separate analytical approaches to build the score. First, we used Cox regression with cross validation techniques to identify factors associated with the outcome in both univariable (p<0.10) and multivariable analyses (p<0.05), then assigned points for each variable based on corresponding coefficients. Second, we used regularized Cox regression, XGBoost, and Random Forest machine learning techniques to create an estimator using all available covariates. We used Harrel’s C-statistic to measure discriminatory performance.

Results: Among 21,420 patients hospitalized with COVID-19 (mean age 61 years, 54% men), 312 (1.5%) had a cerebrovascular event. Using traditional Cox regression, we created and internally validated a risk stratification score (CANDLE) (Fig) with a C-statistic of 0.66 (95% CI, 0.60-0.72). The machine learning estimator had similar discriminatory performance, with a C-statistic of 0.69 (95% CI, 0.65-0.72). For ischemic stroke or TIA, CANDLE’s C-statistic was 0.67 (95% 0.59-0.76).

Conclusion: We developed an easy-to-use clinical score, with similar performance to a machine learning estimator, to help stratify stroke risk among patients hospitalized with COVID-19.

Abstract TP188: Predicting Ischemic Stroke And All-cause Mortality Risk In Patients With Heart Failure With Reduced Ejection Fraction And Sinus Rhythm: A Secondary Analysis Of The Warcef Trial

Introduction: There is a known risk of ischemic stroke (IS) and mortality among patients with heart failure with reduced ejection fraction (HFrEF) and sinus rhythm. We identify predictors of IS and all-cause death in patients with left ventricular ejection fraction (LVEF) < 35% and sinus rhythm by a machine-learning approach.

Methods: We performed a post-hoc analysis of the WARCEF trial which randomized patients with LVEF < 35% and sinus rhythm to either aspirin or warfarin. We built two Random Forest for Survival, Longitudinal, and Multivariate (RF-SLAM) algorithms to model the outcomes of IS and all-cause death separately using all baseline variables with missingness < 10%. The training data set was comprised of 70% of observations and the testing set of the remaining 30%. To assess variable importance in outcome prediction, Mean Decrease Accuracy was computed for each variable over all out-of-bag cross-validated predictions.

Results: In 2,298 participants (median age 61.5 years [IQR 54.3-69.6], 20% female) during a mean follow-up of 3.5 years (SD 1.8 years), 84 (3.7%) patients had an ischemic stroke and 547 (23.8%) died. Patient-specific characteristics contributing most to ischemic stroke prediction with variable Mean Decrease Accuracies ≥ 2.5 were prior transient ischemic attack, CHA 2 DS 2 -VASc score, age, prior stroke, glucose, and blood urea nitrogen (model accuracy 0.95; 95% C.I. 0.93-0.97). Age, hemoglobin, glucose, INR, platelet count, BUN, and systolic blood pressure were the most important patient-specific predictors of all-cause death with variable Mean Decrease Accuracies ≥ 2.5 (model accuracy 0.76; 95% C.I. 0.72-0.79).

Conclusions: Clinical and serologic characteristics identified by the RF-SLAM algorithm predict IS and all-cause death risks in patients with HFrEF and sinus rhythm. Future studies are needed to assess the impact of these factors on treatment effects in heart failure trials evaluating outcomes which include stroke.

Abstract TP213: Arcadia CSI (Cognition And Silent Infarcts): Update

Introduction: Cognitive decline and dementia after stroke is a major public healthcare problem, with dementia risk doubling over time, affecting more than 2M people in the US, with no current treatment. Silent brain infarction has been associated with cognitive decline, especially among those at risk for cardio-embolism. The therapeutic challenge is to prevent the occurrence of silent infarction to mitigate proactively the loss of cognitive function.

Methods: The NINDS-funded ARCADIA-CSI is an ancillary study to ARCADIA, a randomized trial comparing apixaban vs aspirin to prevent recurrent clinical stroke in patients with cryptogenic stroke and left atrial cardiopathy. The aim of ARCADIA-CSI is to address whether apixaban might also reduce the incidence of silent infarction and be associated with better cognitive function over time compared to aspirin. Five hundred patients will be enrolled at least 90 days after the ARCADIA index stroke and undergo cognitive assessments at baseline and yearly thereafter using a telephone-based cognitive battery. We are testing the hypothesis that the slope of change in cognitive function is less steep during the follow-up period in patients on apixaban compared to patients on aspirin therapy. We will also collect an initial MRI around the time of the qualifying stroke and a follow-up MRI at the time that the subject completes participation in the ARCADIA parent study to assess the occurrence of new silent infarction.

Results: As of August 12, 2021, the study has enrolled 188 subjects from 78 ARCADIA sites which have been green-lighted for enrollment in ARCADIA-CSI. A total of 61 sites have enrolled at least one subject. To date, there is a 95% completion of baseline cognitive exams and 98% completion at the 1-yr follow-up. We have obtained 91% of the clinical scans of the index stroke of which 95% have undergone central reading and interpretation.

Conclusion: ARCADIA-CSI is designed to identify the most favorable medical approach to prevent the occurrence of silent infarction and cognitive decline in the setting of secondary stroke prevention. An update will be provided regarding the number of patients enrolled, centers green-lighted, and the completion rates of cognitive assessments, and MRIs obtained and interpreted.

Abstract WP112: A Clinical Score To Predict Reduced Ejection Fraction In Acute Ischemic Stroke

Introduction: Transthoracic echocardiography (TTE) is valuable in evaluating stroke etiology. A left ventricular (LV) thrombus, the identification of which can immediately impact clinical management, is rarely seen unless the ejection fraction (EF) is less than 50%. A clinical prediction score to identify stroke patients with EF less than 50% may help guide the timing of TTE after stroke.

Methods: The CAESAR registry includes all patients with ischemic stroke at our medical center. We derived a clinical prediction score using CAESAR data from calendar years 2011-2016. We included all patients who underwent TTE and had a quantitative EF measurement. We selected clinical factors, laboratory values, and vital signs based on biological plausibility and the results of multiple logistical regression with backward selection.

Results: Of 2,116 patients with ischemic stroke from 2011-2016, 1,045 patients had an EF measurement. The mean age was 63 (SD, 15), 49% were women, and the mean EF was 63% (SD, 14%). Reduced EF was identified in 171 patients (16%). Our final model comprised historical variables (coronary disease, heart failure, and chronic kidney disease) and clinical parameters from the time of admission (NIHSS score, heart rate, serum potassium, and serum creatinine). The model AUC was 0.80 (95% CI, 0.76-0.85) and model calibration was good (Figure). At a predicted probability threshold of 0.1, the score’s sensitivity for reduced EF was 80% with a specificity of 62%. In a sensitivity analysis excluding patients with atrial fibrillation, the AUC was 0.77 (95% CI 0.70-0.83) and calibration remained good.

Conclusions: We derived a clinical score with good performance for predicting reduced EF in acute ischemic stroke patients. If externally validated, such a score may help identify which patients are most likely to benefit from an expedited inpatient TTE.

Abstract WP74: An Automated, Electronic Health Record-based Algorithm To Classify Ischemic Stroke Etiology

Introduction: Determining acute ischemic stroke (AIS) etiology is central to secondary stroke prevention, but can be diagnostically challenging. We built a stroke etiology classification model using electronic health record (EHR) data from non-cryptogenic AIS hospitalization encounters.

Methods: We studied discharge summaries of non-cryptogenic AIS patients hospitalized at 2 academic, Comprehensive Stroke Centers from 2015-2020. The outcome was stroke etiology encoded in each institution’s stroke registry, abstracted from the discharge attending’s impression. We engineered variables including 1) clinical features from Unified Medical Language System concepts identified by a text mining tool, MetaMap , and 2) neuroimaging, echocardiographic, and laboratory features by regular expression operations. XGBoost classifier models were generated (80% training set, 20% testing set). A grid search of 36 model parameter value combinations and 10-fold cross validation were performed. We assessed variable importance in the optimized algorithm by calculating each feature’s Shapley value, the absolute value of the variable’s mean impact in predicting each specific stroke etiology.

Results: The cohort was comprised of 1,993 patients (mean age 69 years, 55% male). We engineered a total of 2,004 features. Mean cross-validated accuracies of the best model in the training and validation sets were: 73.0% and 65.5%, respectively. Validation precision, recall, and F1 weighted scores were 66.2%, 65.5%, and 64.1% (mean cross-validated). The top 20 features contributing to etiology prediction are in Figure 1.

Conclusion: We developed an EHR-based, automated tool to replicate a discharging attending’s stroke etiology diagnosis in non-cyptogenic patients. With further training in representative cohorts of non-cryptogenic and cryptogenic patients with an eventually diagnosed etiology, this algorithm may aide stroke etiology diagnosis before hospital discharge.

Abstract WMP81: Association Between Systemic Amyloidosis And Intracranial Hemorrhage

Introduction: Isolated amyloid deposition in the brain is associated with intracranial hemorrhage. Whether systemic amyloidosis also increases the risk of intracranial hemorrhage is unclear.

Methods: We evaluated the association between systemic amyloidosis and intracranial hemorrhage using claims data from a 5% national sample of Medicare beneficiaries from 2008-2015. The primary outcome was non-traumatic intracranial hemorrhage, defined as a composite of intracerebral hemorrhage, subarachnoid hemorrhage, and subdural hemorrhage. Secondary outcome were each hemorrhage type assessed separately. The exposure and outcomes were identified using previously validated ICD-9-CM diagnosis codes. We used Cox regression analysis adjusting for demographics and vascular risk factors to evaluate the association between systemic amyloidosis and intracranial hemorrhage. We also examined the risk of hip fracture (negative control). In sensitivity analyses, we excluded patients with cardiac amyloidosis, a subset most likely to be on antithrombotic therapy.

Results: Among 1.8 million Medicare beneficiaries, 924 were diagnosed with systemic amyloidosis. During a median follow-up of 5.3 years (IQR, 2.8- 6.7), the cumulative incidence of intracranial hemorrhage was 19 per 1,000 patients per year among patients with amyloidosis, and 2 per 1,000 patients per year in those without amyloidosis. In adjusted Cox models, systemic amyloidosis was associated with an increased risk of intracranial hemorrhage (HR, 4.3; 95% CI, 2.9-6.3). The association persisted in a sensitivity analysis after excluding beneficiaries with cardiac amyloidosis (HR, 8.0; 95% CI, 5.0-12.7). In secondary analyses, systemic amyloidosis was associated with intracerebral hemorrhage (HR, 5.6; 95% CI, 3.6-8.7), subarachnoid hemorrhage (HR, 14.7; 95% 9.0-24.0), and subdural hemorrhage (HR, 3.6; 95% 2.0-6.2). There was no association between systemic amyloidosis and hip fracture (HR, 0.9; 95% CI, 0.6-1.4).

Conclusions: In a large, heterogeneous national cohort of elderly patients, a diagnosis of systemic amyloidosis was associated with a 4-fold increased risk of intracranial hemorrhage, including intracerebral, subarachnoid, and subdural hemorrhages.

Abstract WMP85: Postpartum Risk Of Cerebral Venous Thrombosis

Background: The postpartum state is associated with a heightened risk of thrombosis. The duration of heightened risk for postpartum cerebral venous thrombosis (CVT) is uncertain.

Methods: Using claims data from the Healthcare Cost and Utilization Project (HCUP) from all emergency departments and acute care hospitalizations in Florida from 2005-2015 and New York from 2006-2015, we identified women aged ≥18 years old who were hospitalized for labor and delivery. CVT was ascertained using previously validated International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM), diagnosis codes. For women with multiple labor-related hospitalizations during a single 40-week period, we excluded cases of false labor by identifying delivery as the latest hospitalization during that time. Patients with claims for CVT before their first recorded delivery, and women with a second delivery during the follow-up period were also excluded. We compared the likelihood of a first-ever recorded CVT during postpartum days 0-41 compared with the same period 1 year later. We repeated this crossover-cohort analysis for consecutive 6-weeks periods after delivery, as compared with the corresponding 6-week period 1 year later. We used McNemar's to calculate odds ratios for each 6-week interval.

Results: Among the 1,406,447 women with a first recorded delivery, the risk of CVT was markedly higher within the 6 weeks after delivery than in the same period 1 year later (22 versus 3 CVTs per million deliveries). This corresponded to an absolute risk difference of 19 events per million (95% confidence interval [CI], 11-27) and an odds ratio of 10.0 (95% CI, 3.1-51.2). There was no significant increase in the risk of CVT during the period of 7 to 12 weeks after delivery as compared with the same period 1 year later with an absolute risk difference of 6.0 events (95% CI, 0-11) per million deliveries and an odds ratio of 3.0 (95% CI, 0.9-12.8).

Conclusion: There appears to be a heightened risk of CVT for 6 weeks after delivery.

Abstract WP57: Association Between Stroke Presentation During Off-hours And Mechanical Thrombectomy

Background: Access to mechanical thrombectomy in the US remains limited, in part due to a relative lack of trained interventionalists. Given potential staffing challenges, we hypothesized that access to thrombectomy would be worse on nights and weekends.

Methods: We used 2016-2018 all-payer claims data from all nonfederal emergency departments and acute care hospitals across 11 US states encompassing 80 million residents. Using recorded arrival times, hospital presentation was classified as on-hours if it fell between 8:00 a.m. and 6:00 p.m. on weekdays and as off-hours otherwise. For patients who underwent interhospital transfer, we used the arrival time at the initial hospital. We examined the association between off-hours arrival and mechanical thrombectomy using multiple logistic regression adjusted for age, sex, race/ethnicity, insurance type, socioeconomic status, urban-rural location of residence, the Charlson comorbidity index, initial presentation to a thrombectomy hub, and treatment with intravenous thrombolysis. We performed a sensitivity analysis limited to patients who presented with a probable large-vessel occlusion, defined as a documented NIHSS score ≥12, to a thrombectomy hub and underwent intravenous thrombolysis.

Results: Among 169,199 patients with ischemic strokes, the 82,784 (48.9%) who presented during off-hours had higher NIHSS scores (4 [IQR, 2-10] vs 2 [IQR, 1-9], P <0.001) and underwent thrombolysis more often (9.3% vs 8.5%, P <0.001). There were no differences between groups in rates of mechanical thrombectomy (3.4% on-hours vs 3.5% off-hours, P = 0.25). In adjusted models, off-hours presentation was not significantly associated with lower odds of mechanical thrombectomy (OR, 0.94; 95% CI, 0.85-1.03). Our findings were similar in a sensitivity analysis limited to patients with a probable large-vessel occlusion who initially presented to a thrombectomy hub and underwent intravenous thrombolysis (OR, 0.87; 0.69-1.09).

Conclusions: In a large population-based sample of ischemic stroke patients across the US, the odds of mechanical thrombectomy did not vary by time of presentation.

Acute Ischemic Stroke, Depressed Left Ventricular Ejection Fraction, and Sinus Rhythm: Prevalence and Practice Patterns

BACKGROUND

There are limited data about the epidemiology and secondary stroke prevention strategies used for patients with depressed left ventricular ejection fraction (LVEF) and sinus rhythm following an acute ischemic stroke (AIS). We sought to describe the prevalence of LVEF ≤40% and sinus rhythm among patients with AIS and antithrombotic treatment practice in a multi-center cohort from 2002 to 2018.

METHODS

This was a multi-center, retrospective cohort study comprised of patients with AIS hospitalized in the Greater Cincinnati Northern Kentucky Stroke Study and 4 academic, hospital-based cohorts in the United States. A 1-stage meta-analysis of proportions was undertaken to calculate a pooled prevalence. Univariate analyses and an adjusted multivariable logistic regression model were performed to identify demographic, clinical, and echocardiographic characteristics associated with being prescribed an anticoagulant upon AIS hospitalization discharge.

RESULTS

Among 14 338 patients with AIS with documented LVEF during the stroke hospitalization, the weighted pooled prevalence of LVEF ≤40% and sinus rhythm was 5.0% (95% CI, 4.1-6.0%; I², 84.4%). Of 524 patients with no cardiac thrombus and no prior indication for anticoagulant who survived postdischarge, 200 (38%) were discharged on anticoagulant, 289 (55%) were discharged on antiplatelet therapy only, and 35 (7%) on neither. There was heterogeneity by site in the proportion discharged with an anticoagulant (22% to 45%, P<0.0001). Cohort site and National Institutes of Health Stroke Severity scale >8 (odds ratio, 2.0 [95% CI, 1.1-3.8]) were significant, independent predictors of being discharged with an anticoagulant in an adjusted analysis.

CONCLUSIONS

Nearly 5% of patients with AIS have a depressed LVEF and are in sinus rhythm. There is significant variation in the clinical practice of antithrombotic therapy prescription by site and stroke severity. Given this clinical equipoise, further study is needed to define optimal antithrombotic treatment regimens for secondary stroke prevention in this patient population.

Atrial Fibrillation and Stroke Symptoms in the REGARDS Study

Background

It is unknown if stroke symptoms in the absence of a stroke diagnosis are a sign of subtle cardioembolic phenomena. The objective of this study was to examine associations between atrial fibrillation (AF) and stroke symptoms among adults with no clinical history of stroke or transient ischemic attack (TIA).

Methods and Results

We evaluated associations between AF and self‐reported stroke symptoms in the national, prospective REGARDS (Reasons for Geographic and Racial Differences in Stroke) cohort. We conducted cross‐sectional (n=27 135) and longitudinal (n=21 932) analyses over 8 years of follow‐up of REGARDS participants without stroke/transient ischemic attack and stratified by anticoagulant or antiplatelet agent use. The mean age was 64.4 (SD±9.4) years, 55.3% were women, and 40.8% were Black participants; 28.6% of participants with AF reported stroke symptoms. In the cross‐sectional analysis, comparing participants with and without AF, the risk of stroke symptoms was elevated for adults with AF taking neither anticoagulants nor antiplatelet agents (odds ratio [OR], 2.22; 95% CI, 1.89–2.59) or antiplatelet agents only (OR, 1.92; 95% CI, 1.61–2.29) but not for adults with AF taking anticoagulants (OR, 1.08; 95% CI, 0.71–1.65). In the longitudinal analysis, the risk of stroke symptoms was also elevated for adults with AF taking neither anticoagulants nor antiplatelet agents (hazard ratio [HR], 1.41; 95% CI, 1.21–1.66) or antiplatelet agents only (HR, 1.23; 95% CI, 1.04–1.46) but not for adults with AF taking anticoagulants (HR, 0.86; 95% CI, 0.62–1.18).

Conclusions

Stroke symptoms in the absence of a stroke diagnosis may represent subclinical cardioembolic phenomena or “whispering strokes.” Future studies examining the benefit of stroke symptom screening may be warranted.

Atrial Fibrillation Detected After Stroke and Transient Ischemic Attack: A Novel Clinical Concept Challenging Current Views

Atrial fibrillation (AF) can be newly detected in approximately one-fourth of patients with ischemic stroke and transient ischemic attack without previously recognized AF. We present updated evidence supporting that AF detected after stroke or transient ischemic attack (AFDAS) may be a distinct clinical entity from AF known before stroke occurrence (known atrial fibrillation). Data suggest that AFDAS can arise from the interplay of cardiogenic and neurogenic forces. The embolic risk of AFDAS can be understood as a gradient defined by the prevalence of vascular comorbidities, the burden of AF, neurogenic autonomic changes, and the severity of atrial cardiopathy. The balance of existing data indicates that AFDAS has a lower prevalence of cardiovascular comorbidities, a lower degree of cardiac abnormalities than known atrial fibrillation, a high proportion (52%) of very brief (<30 seconds) AF paroxysms, and is more frequently associated with insular brain infarction. These distinctive features of AFDAS may explain its recently observed lower associated risk of stroke than known atrial fibrillation. We present an updated ad-hoc meta-analysis of randomized clinical trials in which the association between prolonged cardiac monitoring and reduced risk of ischemic stroke was nonsignificant (incidence rate ratio, 0.90 [95% CI, 0.71-1.15]). These findings highlight that larger and sufficiently powered randomized controlled trials of prolonged cardiac monitoring assessing the risk of stroke recurrence are needed. Meanwhile, we call for further research on AFDAS and stroke recurrence, and a tailored approach when using prolonged cardiac monitoring after ischemic stroke or transient ischemic attack, focusing on patients at higher risk of AFDAS and, more importantly, at higher risk of cardiac embolism.

Long-Term Risk of Ischemic Stroke among Elderly Survivors of Non-Traumatic Subarachnoid Hemorrhage

INTRODUCTION

Non-traumatic subarachnoid hemorrhage (SAH) is associated with poor long-term functional outcomes, but the risk of ischemic stroke among SAH survivors is poorly understood.

OBJECTIVES

The aim of this study was to evaluate the risk of ischemic stroke among survivors of SAH.

METHODS

We performed a retrospective cohort study using claims data from Medicare beneficiaries from 2008 to 2015. The exposure was a diagnosis of SAH, while the outcome was an acute ischemic stroke, both identified using previously validated ICD-9-CM diagnosis codes. We used Cox regression analysis adjusting for demographics and stroke risk factors to evaluate the association between SAH and long-term risk of ischemic stroke.

RESULTS

Among 1.7 million Medicare beneficiaries, 912 were hospitalized with non-traumatic SAH. During a median follow-up of 5.2 years (IQR, 2.7-6.7), the cumulative incidence of ischemic stroke was 22 per 1,000 patients per year among patients with SAH, and 7 per 1,000 patients per year in those without SAH. In adjusted Cox models, SAH was associated with an increased risk of ischemic stroke (HR, 2.0; 95% confidence interval, 1.4-2.8) as compared to beneficiaries without SAH. Similar results were obtained in sensitivity analyses, when treating death as a competing risk (sub HR, 3.0; 95% CI, 2.8-3.3) and after excluding ischemic stroke within 30 days of SAH discharge (HR, 1.5; 95% CI, 1.1-2.3).

CONCLUSIONS

In a large, heterogeneous national cohort of elderly patients, survivors of SAH had double the long-term risk of ischemic stroke. SAH survivors should be closely monitored and risk stratified for ischemic stroke.

Impact of Cigarette Smoking and Its Interaction with Hypertension and Diabetes on Cognitive Function in Older Americans

BACKGROUND

The detrimental impact of tobacco smoking on brain health is well recognized.

OBJECTIVE

To evaluate whether smoking acts synergistically with hypertension and diabetes to influence cognitive performance.

METHODS

We performed a cross-sectional analysis using the US National Health and Nutrition Examination Survey. Participants were tested for serum cotinine, a validated cigarette smoking/exposure biomarker, and had standardized blood pressure and hemoglobin A1c measurements. Participants were administered four cognitive tests: Digit Symbol Substitution (DSST), Animal Fluency, Immediate Recall, and Delayed Recall. Multivariable linear regression models adjusted for demographics and confounders evaluated the association of cotinine with cognition. Interaction testing evaluated effect modification by hypertension, diabetes, and their continuous measures (systolic blood pressure and hemoglobin A1c).

RESULTS

For 3,007 participants, mean age was 69.4 years; 54% were women. Using cotinine levels, 14.9% of participants were categorized as active smokers. Higher cotinine levels were associated with worse DSST performance when modeling cotinine as a continuous variable (β, -0.70; 95% CI, -1.11, -0.29; p < 0.01) and when categorizing participants as active smokers (β, -5.63; 95% CI, -9.70, -1.56; p < 0.01). Cotinine was not associated with fluency or memory. Effect modification by hypertension and diabetes were absent, except that cotinine was associated with worse Immediate Recall at lower blood pressures.

CONCLUSION

Higher levels of a smoking and secondhand exposure biomarker were associated with worse cognitive performance on a multidomain test. Overall, the relationship of cotinine with cognition was not contingent on or amplified by hypertension or diabetes; smoking is detrimental for brain health irrespective of these comorbidities.

Risk of Mortality After an Arterial Ischemic Event Among Intracerebral Hemorrhage Survivors

BACKGROUND AND PURPOSE

The impact of arterial ischemic events after intracerebral hemorrhage (ICH) on outcomes is unclear. This study aimed to evaluate the risk of death among ICH survivors with and without an incident arterial ischemic event.

METHODS

We performed a retrospective cohort study using claims data from Medicare beneficiaries with a non-traumatic ICH from January 2008 to October 2015. Our exposure was an arterial ischemic event, a composite of acute ischemic stroke or myocardial infarction (MI), identified using validated ICD-9-CM diagnosis codes. The outcome was mortality. We used marginal structural models to analyze the risk of death among ICH patients with and without an arterial ischemic event, after adjusting for confounders as time-varying covariates.

RESULTS

Among 8,804 Medicare beneficiaries with ICH, 2,371 (26.9%) had an arterial ischemic event. During a median follow-up time of 1.9 years (interquartile range, 0.7-3.9), ICH patients with an arterial ischemic event had a mortality rate of 21.7 (95% confidence interval [CI], 20.4-23.0) per 100 person-years compared to a rate of 15.0 (95% CI, 14.4-15.6) per 100 person-years in those without. In the marginal structural model, an arterial ischemic event was associated with an increased risk of death (hazard ratio [HR], 1.8; 95% confidence interval [CI], 1.6-1.9). In secondary analyses, the mortality risk was elevated after an ischemic stroke (HR, 1.7; 95% CI, 1.5-1.8), and MI (HR, 3.0; 95% CI, 2.4-3.8).

CONCLUSIONS

We found that elderly patients who survived an ICH had an increased risk of death after a subsequent ischemic stroke or MI.

Association of Reproductive History With Brain MRI Biomarkers of Dementia Risk in Midlife

BACKGROUND AND OBJECTIVES

To examine associations between indicators of estrogen exposure from women's reproductive history and brain MRI biomarkers of Alzheimer disease (AD) in midlife.

METHODS

We evaluated 99 cognitively normal women 52 ± 6 years of age and 29 men 52 ± 7 years of age with reproductive history data, neuropsychological testing, and volumetric MRI scans. We used multiple regressions to examine associations among reproductive history indicators, voxel-wise gray matter volume (GMV), and memory and global cognition scores, adjusting for demographics and midlife health indicators. Exposure variables were menopause status, age at menarche, age at menopause, reproductive span, hysterectomy status, number of children and pregnancies, and use of menopause hormonal therapy (HT) and hormonal contraceptives (HC).

RESULTS

All menopausal groups exhibited lower GMV in AD-vulnerable regions compared to men, with perimenopausal and postmenopausal groups also exhibiting lower GMV in temporal cortex compared to the premenopausal group. Reproductive span, number of children and pregnancies, and use of HT and HC were positively associated with GMV, chiefly in temporal cortex, frontal cortex, and precuneus, independent of age, APOE ε4 status, and midlife health indicators. Although reproductive history indicators were not directly associated with cognitive measures, GMV in temporal regions was positively associated with memory and global cognition scores.

DISCUSSION

Reproductive history events signaling more estrogen exposure such as premenopausal status, longer reproductive span, higher number of children, and use of HT and HC were associated with larger GMV in women in midlife. Further studies are needed to elucidate sex-specific biological pathways through which reproductive history influences cognitive aging and AD risk.

Association Between Intraventricular Alteplase Use and Parenchymal Hematoma Volume in Patients With Spontaneous Intracerebral Hemorrhage and Intraventricular Hemorrhage

IMPORTANCE

Intraventricular thrombolysis reduces intraventricular hemorrhage (IVH) volume in patients with spontaneous intracerebral hemorrhage (ICH), but it is unclear if a similar association with parenchymal ICH volume exists.

OBJECTIVE

To evaluate the association between intraventricular alteplase use and ICH volume as well as the association between a change in parenchymal ICH volume and long-term functional outcomes.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study was a post hoc exploratory analysis of data from the Clot Lysis: Evaluating Accelerated Resolution of Intraventricular Hemorrhage phase 3 randomized clinical trial with blinded outcome assessments. Between September 1, 2009, and January 31, 2015, patients with ICH and IVH were randomized to receive either intraventricular alteplase or normal saline via an external ventricular drain. Participants with primary IVH were excluded. Data analyses were performed between January 1 and June 30, 2021.

EXPOSURE

Randomization to receive intraventricular alteplase.

MAIN OUTCOMES AND MEASURES

The primary outcome was the change in parenchymal ICH volume between the hematoma stability and end-of-treatment computed tomography scans. Secondary outcomes were a modified Rankin Scale score higher than 3 and mortality, both of which were assessed at 6 months. The association between alteplase and change in parenchymal ICH volume was assessed using multiple linear regression, whereas the associations between change in parenchymal ICH volume and 6-month outcomes were assessed using multiple logistic regression. Prespecified subgroup analyses were performed for baseline IVH volume, admission ICH volume, and ICH location.

RESULTS

A total of 454 patients (254 men [55.9%]; mean [SD] age, 59 [11] years) were included in the study. Of these patients, 230 (50.7%) were randomized to receive alteplase and 224 (49.3%) to receive normal saline. The alteplase group had a greater mean (SD) reduction in parenchymal ICH volume compared with the saline group (1.8 [0.2] mL vs 0.4 [0.1] mL; P < .001). In the primary analysis, alteplase use was associated with a change in the parenchymal ICH volume in the unadjusted analysis per 1-mL change (β, 1.37; 95% CI, 0.92-1.81; P < .001) and in multivariable linear regression analysis that was adjusted for demographic characteristics, stability ICH and IVH volumes, ICH location, and time to first dose of study drug per 1-mL change (β, 1.20; 95% CI, 0.79-1.62; P < .001). In the secondary analyses, no association was found between change in parenchymal ICH volume and poor outcome (odds ratio [OR], 0.97; 95% CI 0.87-1.10; P = .64) or mortality (OR, 0.97; 95% CI 0.99-1.08; P = .59). Similar results were observed in the subgroup analyses.

CONCLUSIONS AND RELEVANCE

This study found that intraventricular alteplase use in patients with a large IVH was associated with a small reduction in parenchymal ICH volume, but this association did not translate into improved functional outcomes or mortality. Intraventricular thrombolysis should be examined in patients with moderate to large ICH with IVH, especially in a thalamic location.

Smoking Cessation in Stroke Survivors in the United States: A Nationwide Analysis

BACKGROUND AND PURPOSE

Continued smoking after stroke is associated with a high risk of stroke recurrence and other cardiovascular disease. We sought to comprehensively understand the epidemiology of smoking cessation in stroke survivors in the United States. Furthermore, we compared smoking cessation in stroke and cancer survivors because cancer is another smoking-related condition in which smoking cessation is prioritized.

METHODS

We performed a cross-sectional analysis of data from the Centers for Disease Control and Prevention Behavioral Risk Factor Surveillance System, an annual, nationally representative health survey. Using pooled data from 2013 to 2019, we identified stroke and cancer survivors with a history of smoking. We used survey procedures to estimate frequencies and summarize quit ratios with attention to demographic and geographic (state-wise and rural-urban) factors for stroke survivors. The quit ratio is conventionally defined as the proportion of ever smokers who have quit. Then, we used multivariable logistic regression to compare quit ratios in stroke and cancer survivors while adjusting for demographics and smoking-related comorbidities.

RESULTS

Among 4 434 604 Americans with a history of stroke and smoking, the median age was 68 years (interquartile range, 59-76), and 45.4% were women. The overall quit ratio was 60.8% (95% CI, 60.1%-61.6%). Quit ratios varied by age group, sex, race and ethnicity, and several geographic factors. There was marked geographic variation in quit ratios, ranging from 48.3% in Kentucky to 71.5% in California. Furthermore, compared with cancer survivors, stroke survivors were less likely to have quit smoking (odds ratio, 0.72 [95% CI, 0.67-0.79]) after accounting for differences in demographics and smoking-related comorbidities.

CONCLUSIONS

There were considerable demographic and geographic disparities in smoking quit ratios in stroke survivors, who were less likely to have quit smoking than cancer survivors. A targeted initiative is needed to improve smoking cessation for stroke survivors.

Carotid Artery Plaque Calcifications: Lessons From Histopathology to Diagnostic Imaging

The role of calcium in atherosclerosis is controversial and the relationship between vascular calcification and plaque vulnerability is not fully understood. Although calcifications are present in ≈50% to 60% of carotid plaques, their association with cerebrovascular ischemic events remains unclear. In this review, we summarize current understanding of carotid plaque calcification. We outline the role of calcium in atherosclerotic carotid disease by analyzing laboratory studies and histopathologic studies, as well as imaging findings to understand clinical implications of carotid artery calcifications. Differences in mechanism of calcium deposition express themselves into a wide range of calcification phenotypes in carotid plaques. Some patterns, such as rim calcification, are suggestive of plaques with inflammatory activity with leakage of the vasa vasourm and intraplaque hemorrhage. Other patterns such as dense, nodular calcifications may confer greater mechanical stability to the plaque and reduce the risk of embolization for a given degree of plaque size and luminal stenosis. Various distributions and patterns of carotid plaque calcification, often influenced by the underlying systemic pathological condition, have a different role in affecting plaque stability. Modern imaging techniques afford multiple approaches to assess geometry, pattern of distribution, size, and composition of carotid artery calcifications. Future investigations with these novel technologies will further improve our understanding of carotid artery calcification and will play an important role in understanding and minimizing stroke risk in patients with carotid plaques.

Left Ventricular Dysfunction Among Patients With Embolic Stroke of Undetermined Source and the Effect of Rivaroxaban vs Aspirin: A Subgroup Analysis of the NAVIGATE ESUS Randomized Clinical Trial

Importance

It is uncertain whether anticoagulation is superior to aspirin at reducing recurrent stroke in patients with recent embolic strokes of undetermined source (ESUS) and left ventricular (LV) dysfunction.

Objective

To determine whether anticoagulation is superior to aspirin in reducing recurrent stroke in patients with ESUS and LV dysfunction.

Design, Setting, and Participants

Post hoc exploratory analysis of data from the New Approach Rivaroxaban Inhibition of Factor Xa in a Global Trial vs Aspirin to Prevent Embolism in ESUS (NAVIGATE ESUS) trial, a randomized, phase 3 clinical trial with enrollment from December 2014 to September 2017. The study setting included 459 stroke recruitment centers in 31 countries. Patients 50 years or older who had neuroimaging-confirmed ESUS between 7 days and 6 months before screening were eligible. Of the 7213 NAVIGATE ESUS participants, 7107 (98.5%) had a documented assessment of LV function at study entry and were included in the present analysis. Data were analyzed in January 2021.

Interventions

Participants were randomized to receive either 15 mg of rivaroxaban or 100 mg of aspirin once daily.

Main Outcomes and Measures

The study examined whether rivaroxaban was superior to aspirin at reducing the risk of (1) the trial primary outcome of recurrent stroke or systemic embolism and (2) the trial secondary outcome of recurrent stroke, systemic embolism, myocardial infarction, or cardiovascular mortality during a median follow-up of 10.4 months. LV dysfunction was identified locally through echocardiography and defined as moderate to severe global impairment in LV contractility and/or a regional wall motion abnormality. A Cox proportional hazards model was used to assess for treatment interaction and to estimate the hazard ratios for those randomized to rivaroxaban vs aspirin by LV dysfunction status.

Results

LV dysfunction was present in 502 participants (7.1%). Of participants with LV dysfunction, the mean (SD) age was 67 (10) years, and 130 (26%) were women. Among participants with LV dysfunction, annualized primary event rates were 2.4% (95% CI, 1.1-5.4) in those assigned to rivaroxaban vs 6.5% (95% CI, 4.0-11.0) in those assigned aspirin. Among the 6605 participants without LV dysfunction, rates were similar between those assigned to rivaroxaban (5.3%; 95% CI, 4.5-6.2) vs aspirin (4.5%; 95% CI, 3.8-5.3). Participants with LV dysfunction assigned to rivaroxaban vs aspirin had a lower risk of the primary outcome (hazard ratio, 0.36; 95% CI, 0.14-0.93), unlike those without LV dysfunction (hazard ratio, 1.16; 95% CI, 0.93-1.46) (P for treatment interaction = .03). Results were similar for the secondary outcome.

Conclusions and Relevance

In this post hoc exploratory analysis, rivaroxaban was superior to aspirin in reducing the risk of recurrent stroke or systemic embolism among NAVIGATE ESUS participants with LV dysfunction.

Trial Registration

ClinicalTrials.gov Identifier: NCT02313909.

Cardiac mechanics and incident ischemic stroke: the Cardiovascular Health Study

Recent evidence indicates that our understanding of the relationship between cardiac function and ischemic stroke remains incomplete. The Cardiovascular Health Study enrolled community-dwelling adults ≥ 65 years old. We included participants with speckle-tracking data from digitized baseline study echocardiograms. Exposures were left atrial reservoir strain (primary), left ventricular longitudinal strain, left ventricular early diastolic strain rate, septal e’ velocity, and lateral e’ velocity. The primary outcome was incident ischemic stroke. Cox proportional hazards models were adjusted for demographics, image quality, and risk factors including left ventricular ejection fraction and incident atrial fibrillation. Among 4,000 participants in our analysis, lower (worse) left atrial reservoir strain was associated with incident ischemic stroke (HR per SD absolute decrease, 1.14; 95% CI 1.04–25). All secondary exposure variables were significantly associated with the outcome. Left atrial reservoir strain was associated with cardioembolic stroke (HR per SD absolute decrease, 1.42; 95% CI 1.21–1.67) and cardioembolic stroke related to incident atrial fibrillation (HR per SD absolute decrease, 1.60; 1.32–1.95). Myocardial dysfunction that can ultimately lead to stroke may be identifiable at an early stage. This highlights opportunities to identify cerebrovascular risk earlier and improve stroke prevention via therapies for early myocardial dysfunction.

Changes in Stroke Hospital Care During the COVID-19 Pandemic: A Systematic Review and Meta-Analysis

BACKGROUND AND PURPOSE

We systematically evaluated the impact of the coronavirus 2019 (COVID-19) pandemic on stroke care across the world.

METHODS

Observational studies comparing characteristics, acute treatment delivery, or hospitalization outcomes between patients with stroke admitted during the COVID-19 pandemic and those admitted before the pandemic were identified by Medline, Scopus, and Embase databases search. Random-effects meta-analyses were conducted for all outcomes.

RESULTS

We identified 46 studies including 129 491 patients. Patients admitted with stroke during the COVID-19 pandemic were found to be younger (mean difference, -1.19 [95% CI, -2.05 to -0.32]; I²=70%) and more frequently male (odds ratio, 1.11 [95% CI, 1.01-1.22]; I²=54%) compared with patients admitted with stroke in the prepandemic era. Patients admitted with stroke during the COVID-19 pandemic, also, had higher baseline National Institutes of Health Stroke Scale scores (mean difference, 0.55 [95% CI, 0.12-0.98]; I²=90%), higher probability for large vessel occlusion presence (odds ratio, 1.63 [95% CI, 1.07-2.48]; I²=49%) and higher risk for in-hospital mortality (odds ratio, 1.26 [95% CI, 1.05-1.52]; I²=55%). Patients with acute ischemic stroke admitted during the COVID-19 pandemic had higher probability of receiving endovascular thrombectomy treatment (odds ratio, 1.24 [95% CI, 1.05-1.47]; I²=40%). No difference in the rates of intravenous thrombolysis administration or difference in time metrics regarding onset to treatment time for intravenous thrombolysis and onset to groin puncture time for endovascular thrombectomy were detected.

CONCLUSIONS

The present systematic review and meta-analysis indicates an increased prevalence of younger patients, more severe strokes attributed to large vessel occlusion, and higher endovascular treatment rates during the COVID-19 pandemic. Patients admitted with stroke during the COVID-19 pandemic had higher in-hospital mortality. These findings need to be interpreted with caution in view of discrepant reports and heterogeneity being present across studies.