Pre admission antithrombotics are associated with improved outcomes following ischaemic stroke: a cohort from the Registry of the Canadian Stroke Network

Effects of preceding antiplatelet agents on severity of ischemic stroke in patients with a history of stroke

INTRODUCTION

Antiplatelet agents are effective for secondary prevention of ischemic stroke and can reduce the severity of first-ever ischemic stroke. However, it is uncertain if prophylactic antiplatelet therapy reduces the severity of recurrent ischemic stroke. The aim of this study was to determine the effect of preceding antiplatelet treatment on the severity of thrombotic stroke (TS) in patients with a prior history of stroke.

METHODS

From a prospective hospital registry of 1338 consecutive patients with acute ischemic stroke, we identified patients with a prior history of stroke who were admitted for cardioembolic stroke (CE); TS including large-artery atherosclerosis, small vessel occlusion, and branch atheromatous disease; or other cause or cryptogenic stroke (OCS). Cases in each subtype were categorized based on preceding medication: antiplatelet agents (AP) and none (N). Severity of stroke (National Institutes of Health Stroke Scale: NIHSS) on admission was compared between AP and N cases.

RESULTS

The total cohort of 252 patients included 83 with CE, 102 with TS, and 67 with OCS. After excluding those with prior anticoagulants, the median NIHSS on admission was lower in AP cases than in N cases (3 vs. 5, p = 0.002). In multivariate analysis, preceding AP treatment was independently associated with minor stroke (NIHSS ≤4) on admission in CE group (OR 8.48, 95% CI 1.71-62.9, p = 0.008) and TS group (OR 4.24, 95% CI 1.44-13.4, p = 0.009).

CONCLUSION

Preceding antiplatelet treatment in patients with a prior history of stroke may reduce the severity of subsequent thrombotic and cardiogenic stroke.

Pre-aspirin use has no benefit on the neurological disability and mortality after cardiovascular events: A nation-wide population-based cohort study

To evaluate the effects of aspirin in the primary prevention, we evaluated disability grades and mortality after ischemic/hemorrhagic stroke and myocardial infarction (MI). A retrospective nation-wide propensity score-matched cohort study was performed using the Korean National Health Information Database. From 3,060,639 subjects who were older than 55 and performed national health examinations in 2004 and 2005, we selected the aspirin group (N = 8770) was composed of patients who had received aspirin prior to cardiovascular events. Cox proportional hazards model was used to compare the acquisition times for neurologic disability grades and survival times between the aspirin and control groups. Only in hemorrhagic stroke, the severe neurologic disability risk was higher in the aspirin group (hazard ratio [HR], 1.21; 95% confidence interval [CI], 1.02-1.42). The aspirin group was associated with higher 90-day (HR, 1.33; 95% CI, 1.23-1.44) and long-term mortality risk (HR, 1.06; 95% CI, 1.03-1.10) after pooling 3 events. The old age was a strong risk factor for 90-day mortality in hemorrhagic stroke (50s: reference; 60s: HR 2.21, 95% CI 1.50-3.25; 70s: HR 3.63, 95% CI 2.48-5.30; 80s: HR 6.69, 95% CI 4.54-9.65; >90s: HR 11.28, 95% CI 6.46-19.70). Pre-aspirin use in cardiovascular events has detrimental effects on severe neurological disability in hemorrhagic stroke and short-/long-term mortality in 3 cardiovascular events. The use of aspirin for the primary prevention especially in the elderly should be very cautious because the old age is a strong risk factor for 90-day mortality after hemorrhagic stroke.

Pre-admission antithrombotic use is associated with 3-month mRS score after thrombectomy for acute ischemic stroke

In patients who undergo thrombectomy for acute ischemic stroke, the relationship between pre-admission antithrombotic (anticoagulation or antiplatelet) use and both radiographic and functional outcome is not well understood. We sought to explore the relationship between pre-admission antithrombotic use in patients who underwent thrombectomy for acute ischemic stroke at two medical centers in New York City between December 2018 and November 2020. Analyses were performed using analysis of variance and Pearson's chi-squared tests. Of 234 patients in the analysis cohort, 65 (28%) were on anticoagulation, 64 (27%) were on antiplatelet, and 105 (45%) with no antithrombotic use pre-admission. 3-month Modified Rankin Scale (mRS) score of 3-6 was associated with pre-admission antithrombotic use (71% anticoagulation vs. 77% antiplatelet vs. 56% no antithrombotic, p = 0.04). There was no relationship between pre-admission antithrombotic use and Thrombolysis in Cerebral Iinfarction (TICI) score, post-procedure Alberta Stroke Program Early CT Score (ASPECTS) score, rate of hemorrhagic conversion, length of hospital admission, discharge NIH Stroke Scale (NIHSS), discharge mRS score, or mortality. When initial NIHSS score, post-procedure ASPECTS score, and age at admission were included in multivariate analysis, pre-admission antithrombotic use was still significantly associated with a 3-month mRS score of 3-6 (OR 2.36, 95% CI 1.03-5.54, p = 0.04). In this cohort of patients with acute ischemic stroke who underwent thrombectomy, pre-admission antithrombotic use was associated with 3-month mRS score, but no other measures of radiographic or functional outcome. Further research is needed on the relationship between use of specific anticoagulation or antiplatelet agents and outcome after acute ischemic stroke, but moreover, improve stroke prevention.

Impact of Pre-Stroke Antiplatelet Use on 3-Month Outcome After Ischemic Stroke

Background

Pre-stroke anti-platelet (PAP) therapy can potentially influence the severity and outcome after ischemic stroke.

Methods

We analyzed data from the prospective multicenter Indo-US collaborative stroke project for the impact of PAP therapy. Outcome measures included the admission National Institute of Health Stroke Scale (NIHSS) score, 3-month modified Rankin scale (mRS) score, and rates of in-hospital mortality and post-ischemic intracerebral hemorrhage.

Results

Among 2048 of 2066 patients (M:F = 2:1) with known pre-stroke medication status, 336 (16.3%) were on PAP therapy. As compared to the non-PAP group, the PAP group had significantly higher mean age (62.2 vs 57.4 years, P < 0.001) and significantly more men, vascular risk factors, cerebral microbleeds (12.8% vs 6.2%, P = 0.001) and intravenous thrombolysis treatment (17% vs. 10.6%, P = 0.001). Cardioembolic strokes were significantly more in the PAP group (P < 0.001), but not large artery atherosclerosis. No significant differences were observed in the median NIHSS score (9 vs. 10, P = 0.274), 3-month mRS (score 0-2,51.4% vs. 49.0%, P = 0.428), in-hospital mortality (8.6% vs. 7.8%, P = 0.592), or symptomatic post ischemic intracerebral haemorrhage (12.2% vs. 10.6%, P = 0.382). The PAP group had more stroke recurrence (6.6% vs. 2.9%, P = 0.002) which was not significant (P = 0.065) after multivariate regression analysis adjusting for age, sex and vascular risk factors. PAP therapy was not an independent predictor of initial stroke severity or stroke outcome.

Conclusion

PAP therapy has no significant effect on initial stroke severity, rates of post-ischemic hemorrhage with or without thrombolysis, in-hospital mortality, stroke recurrence, and 3-month outcome after ischemic stroke.

In-hospital prognosis of first-ever noncardiogenic ischemic stroke in patients with and without indication for prestroke antiplatelet therapy: Chinese Stroke Center Alliance

Background

It is unknown about the influence of prestroke antiplatelet use on early outcomes in patients with and without the indication. We aimed to evaluate the in-hospital prognosis of first-ever noncardiogenic ischemic stroke patients with and without indications of antiplatelet use for primary prevention.

Methods

This was a retrospective, observational study based on a prospective hospital-based registry (Chinese Stroke Center Alliance). Using the data with 436,660 first-ever noncardiogenic acute ischemic strokes recorded from Aug 1, 2015, to July 31, 2019, from 1,453 hospitals in China, we examined the associations between the indication for prestroke antiplatelet use and in-hospital clinical outcomes.

Results

Among 436,660 first-ever noncardiogenic ischemic stroke patients, 42,409 patients (9.7%) had a documented previous vascular indication and 394,251 (90.3%) did not. Compared to those without, patients with the indication were associated with increased prevalence of in-hospital morbid conditions, including stroke severity (OR 2.71; 95% CI: 2.62–2.81; P<0.0001), length of stay >14 days (OR 1.16; 95% CI: 1.13–1.19; P<0.0001), mortality (OR 2.20; 95% CI: 1.96–2.46, P<0.0001), and recurrence of ischemic stroke and transient ischemic attack (TIA) (OR 1.5; 95% CI: 1.43–1.59, P<0.0001). Among patients without indication, prestroke antiplatelet use was associated with lower mortality (OR 0.73, 95% CI: 0.56–0.96; P=0.0221); while among patients with indication, those receiving prestroke antiplatelet had lower odds ratios in stroke severity (P<0.0001) and disability (P=0.0003) than those who not.

Conclusions

Patients with indications of prestroke antiplatelet use were more likely to have unfavorable outcomes than those without. Prestroke antiplatelet might be associated with lower mortality, less disability, and less stroke severity in certain population groups. Future studies to improve risk prediction rules are needed to guide effective primary prevention for ischemic stroke.

Effect of Beta-Blockers on Stroke Outcome: A Meta-Analysis

Introduction

Cardiovascular events and infections are common in the acute phase after stroke. It has been suggested that these complications may be associated with excessive sympathetic activation due to the stroke, and that beta-adrenergic antagonists (beta-blockers) therefore may be beneficial.

Aim

The aim of the current meta-analysis was to investigate the association between beta-blocker treatment in acute stroke and the three outcomes: mortality, functional outcome and post-stroke infections.

Methods

A literature search was performed using the keywords stroke, cerebrovascular disorders, adrenergic beta-antagonists, treatment outcome and mortality. Randomized clinical trials and observational studies were eligible for data extraction. Heterogeneity was investigated using I² statistics. Random effect model was used when heterogeneity presented among studies; otherwise, a fixed-effect model was used. Publication bias was assessed using Egger’s test and by visually inspecting funnel plots.

Results

A total of 20 studies were eligible for at least one of the three outcomes. Two of the included studies were randomized controlled trials and 18 were observational studies. Quality assessments indicated that the risk of bias was moderate. The meta-analysis found no significant association between treatment with beta-blockers and any of the three outcomes. The studies analyzed for the outcomes mortality and infection were heterogeneous, while studies analyzed for functional outcome were homogeneous. The articles analyzed for mortality showed signs of publication bias.

Conclusion

The lack of significant effects in the current meta-analysis, comprising more than 100,000 patients, does not support the proposed beneficial effects of beta-blockers in the acute phase of stroke.

Safety and efficacy of intravenous thrombolysis in stroke patients on prior antiplatelet therapy in the WAKE-UP trial

Background

One quarter to one third of patients eligible for systemic thrombolysis are on antiplatelet therapy at presentation. In this study, we aimed to assess the safety and efficacy of intravenous thrombolysis in stroke patients on prescribed antiplatelet therapy in the WAKE-UP trial.

Methods

WAKE-UP was a multicenter, randomized, double-blind, placebo-controlled clinical trial to study the efficacy and safety of MRI-guided intravenous thrombolysis with alteplase in patients with an acute stroke of unknown onset time. The medication history of all patients randomized in the WAKE-UP trial was documented. The primary safety outcome was any sign of hemorrhagic transformation on follow-up MRI. The primary efficacy outcome was favorable functional outcome defined by a score of 0–1 on the modified Rankin scale at 90 days after stroke, adjusted for age and baseline stroke severity. Logistic regression models were fitted to study the association of prior antiplatelet treatment with outcome and treatment effect of intravenous alteplase.

Results

Of 503 randomized patients, 164 (32.6%) were on antiplatelet treatment. Patients on antiplatelet treatment were older (70.3 vs. 62.8 years, p <  0.001), and more frequently had a history of hypertension, atrial fibrillation, diabetes, hypercholesterolemia, and previous stroke or transient ischaemic attack. Rates of symptomatic intracranial hemorrhage and hemorrhagic transformation on follow-up imaging did not differ between patients with and without antiplatelet treatment. Patients on prior antiplatelet treatment were less likely to achieve a favorable outcome (37.3% vs. 52.6%, p = 0.014), but there was no interaction of prior antiplatelet treatment with intravenous alteplase concerning favorable outcome (p = 0.355). Intravenous alteplase was associated with higher rates of favorable outcome in patients on prior antiplatelet treatment with an adjusted odds ratio of 2.106 (95% CI 1.047–4.236).

Conclusions

Treatment benefit of intravenous alteplase and rates of post-treatment hemorrhagic transformation were not modified by prior antiplatelet intake among MRI-selected patients with unknown onset stroke. Worse functional outcome in patients on antiplatelets may result from a higher load of cardiovascular co-morbidities in these patients.

Antiplatelet therapy within 24 hours of tPA: lessons learned from patients requiring combined thrombectomy and stenting for acute ischemic stroke

Objective

Although stroke guidelines recommend antiplatelets be started 24 hours after tissue plasminogen activator (tPA), select mechanical thrombectomy (MT) patients with luminal irregularities or underlying intracranial atherosclerotic disease may benefit from earlier antiplatelet administration.

Methods

We explore the safety of early (<24 hours) post-tPA antiplatelet use by retrospectively reviewing patients who underwent MT and stent placement for acute ischemic stroke from June 2015 to April 2018 at our institution.

Results

Six patients met inclusion criteria. Median presenting and pre-operative National Institutes of Health Stroke Scale scores were 14 (Interquartile Range [IQR] 5.5–17.3) and 16 (IQR 13.7–18.7), respectively. Five patients received standard intravenous (IV) tPA and one patient received intra-arterial tPA. Median time from symptom onset to IV tPA was 120 min (IQR 78–204 min). Median time between tPA and antiplatelet administration was 4.9 hours (IQR 3.0–6.7 hours). Clots were successfully removed from the internal carotid artery (ICA) or middle cerebral artery (MCA) in 5 patients, the anterior cerebral artery (ACA) in one patient, and the vertebrobasilar junction in one patient. All patients underwent MT before stenting and achieved thrombolysis in cerebral infarction 2B recanalization. Stents were placed in the ICA (n=4), common carotid artery (n=1), and basilar artery (n=1). The median time from stroke onset to endovascular access was 185 min (IQR 136–417 min). No patients experienced symptomatic post-procedure intracranial hemorrhage (ICH). Median modified Rankin Scale score on discharge was 3.5.

Conclusions

Antiplatelets within 24 hours of tPA did not result in symptomatic ICH in this series. The safety and efficacy of early antiplatelet administration after tPA in select patients following mechanical thrombectomy warrants further study.

Aspirin Resistance and Stroke

Stroke is a leading cause of death and disability worldwide. Aspirin is the most commonly used antiplatelet drug in both primary and secondary prevention of cerebrovascular and cardiovascular diseases. A proportion of patients may have stroke recurrence while they are on treatment with aspirin, giving rise to term aspirin resistance or aspirin failure. Studies have suggested that such recurrence could partly be attributed to biochemical aspirin resistance, with an estimated prevalence ranging between 5% and 65% among patients with ischemic stroke in the published studies. Common methods to evaluate laboratory aspirin resistance include light transmission aggregometry, PFA-100, VerifyNow-Aspirin assay, serum thromboxane B2, and urinary 11-dehydrothromboxane B2. Aspirin resistance is multifactorial in origin and involves diverse environmental and genetic factors, including single-nucleotide polymorphisms, miRNAs, drug interactions, and co-morbid risk factors. The current review overviews the concept of aspirin resistance, its evaluation and relationship with stroke recurrence, its outcome, and its implications on stroke management in the future.

Simultaneous acute cardio-cerebral infarction: is there a consensus for management?

Acute ischemic stroke (AIS) and acute myocardial infarction (AMI) are both life-threatening medical conditions with narrow therapeutic time-window that carry grave prognosis if not addressed promptly. The acute management of both condition is well documented in the literature, however the management of a simultaneous presentation of both AIS and AMI is unclear. A delayed intervention of one infarcted territory for the other may result in permanent irreversible morbidity or disability, and even death. In addition, the use of antiplatelet and anticoagulants that are inherently part of an AMI management may increase the risk for hemorrhagic conversion associated with intravenous thrombolysis used in AIS, and the use of a thrombolytic in AIS increases the risk of cardiac wall rupture in the setting of an AMI. Despite this ambiguity, there is no clear evidence-based guideline or clinical studies that have addressed the optimal management of this rare co-occurrence. This review paper examines the existing literature on the management of simultaneous acute cardio-cerebral infarction (CCI) and highlights the existing challenge to management.

Antiplatelet Usage Impacts Clot Density in Acute Anterior Circulation Ischemic Stroke

We explored whether clot density in middle cerebral artery (MCA) occlusion is related to clinical variables, stroke etiology, blood constituents, and prestroke medication. We performed a retrospective chart review of patients with acute ischemic stroke of the anterior circulation admitted to two Central European stroke centers. The acquisition of non-contrast enhanced CT (NECT) and CT angiography (CTA) within 4.5 h of symptom onset was obligatory. We assessed the site of MCA occlusion as well as density, area, and length of the clot in 150 patients. The Hounsfield unit values for the clot were divided with contralateral MCA segment to yield relative Hounsfield Unit ratio (rHU). The site of the vessel occlusion (M1 vs. M2) and antiplatelet usage, but not stroke etiology, significantly influenced rHU. We found an inverse correlation of rHU with erythrocyte count (p < 0.001). The multivariate analysis revealed that a higher rHU (i.e., clot being more hyperdense) was more likely with the use of antiplatelets (OR 4.24, CI 1.10-16.31, p = 0.036). Erythrocyte (OR 0.18, CI 0.05-0.55, p = 0.003), and thrombocyte counts (OR 0.99, CI 0.98-0.99, p = 0.029) were associated with odds for more hypodense clots (lower rHU). Our study disclosed that antiplatelet therapy impacts the composition of intracranial clots of the anterior circulation.

Prior Antithrombotic Use Is Associated With Favorable Mortality and Functional Outcomes in Acute Ischemic Stroke

BACKGROUND AND PURPOSE

Antithrombotics are the mainstay of treatment in primary and secondary prevention of stroke, and their use before an acute event may be associated with better outcomes.

METHODS

Using data from Get With The Guidelines-Stroke with over half a million acute ischemic strokes recorded between October 2011 and March 2014 (n=540 993) from 1661 hospitals across the United States, we examined the unadjusted and adjusted associations between previous antithrombotic use and clinical outcomes.

RESULTS

There were 250 104 (46%) stroke patients not receiving any antithrombotic before stroke; of whom approximately one third had a documented previous vascular indication. After controlling for clinical and hospital factors, patients who were receiving antithrombotics before stroke had better outcomes than those who did not, regardless of whether a previous vascular indication was present or not: adjusted odds ratio (95% confidence intervals) were 0.82 (0.80-0.84) for in-hospital mortality, 1.18 (1.16-1.19) for home as the discharge destination, 1.15 (1.13-1.16) for independent ambulatory status at discharge, and 1.15 (1.12-1.17) for discharge modified Rankin Scale score of 0 or 1.

CONCLUSIONS

Previous antithrombotic therapy was independently associated with improved clinical outcomes after acute ischemic stroke. Ensuring the use of antithrombotics in appropriate patient populations may be associated with benefits beyond stroke prevention.

Effect of prestroke antiplatelets use on first-ever ischaemic stroke severity and early outcome

OBJECTIVES

We aimed to investigate whether prior use of antiplatelet agents (AP) may be associated with lower severity and improved short-term outcome of the first-ever acute ischaemic stroke.

METHODS

This was a retrospective, case-control study based on a prospective hospital stroke registry covering consecutive acute stroke patients admitted to a single stroke centre in highly urbanised area (Warsaw, Poland) between 1995 and 2013. Patients receiving oral anticoagulants were excluded from the analysis. Statistical analysis included multiple regression and logistic regression adjusted for age, sex, hypertension, atrial fibrillation, congestive heart failure, diabetes, coronary heart disease and history of myocardial infarction.

RESULTS

During the study period, there were 3036 eligible patients, of whom 879 (29%) received AP before stroke onset. Patients from the AP group were older and more often burdened with stroke risk factors. There were no differences in baseline stroke severity, hospital mortality and proportion of patients alive and independent at discharge. However, AP turned out to be independently associated with lower NIHSS score on admission (β = -0.045, p = 0.008) and increased odds for being alive and independent at discharge (odds ratio 1.36, 95% CI: 1.13-1.67) and decreased odds for in-hospital mortality (odds ratio 0.77, 95% CI: 0.59-0.99).

CONCLUSIONS

Our findings provide further evidence supporting modest benefit of AP therapy on the course and outcome of first-ever ischaemic stroke. Further large studies are needed to confirm this effect.

Aspirin resistance is associated with increased stroke severity and infarct volume

OBJECTIVES

To investigate whether aspirin resistance is associated with initial stroke severity and infarct volume, using diffusion-weighted imaging (DWI) in patients with acute ischemic stroke that occurred while taking aspirin.

METHODS

We studied a total of 310 patients who were admitted within 48 hours of acute ischemic stroke onset. All patients had been taking aspirin for at least 7 days before stroke onset. Aspirin resistance, defined as high residual platelet reactivity (HRPR) on aspirin treatment, was measured using the VerifyNow assay and defined as an aspirin reaction unit ≥550. Initial stroke severity was assessed using the NIH Stroke Scale (NIHSS) score. Infarct volume was measured using DWI.

RESULTS

HRPR occurred in 86 patients (27.7%). The initial NIHSS score (median [interquartile range]) was higher in patients with HRPR than in the non-HRPR group (6 [3-15] vs 3 [1-8], p < 0.001). DWI infarct volumes were also larger in the HRPR group compared to the non-HRPR group (5.4 [0.8-43.2] vs 1.7 [0.4-10.3], p = 0.002). A multivariable median regression analysis showed that HRPR was significantly associated with an increase of 2.1 points on the NIHSS (95% confidence interval 0.8-4.0, p < 0.001) and an increase of 2.3 cm(3) in DWI infarct volume (95% confidence interval 0.4-3.9, p < 0.001).

CONCLUSIONS

Aspirin resistance is associated with an increased risk of severe stroke and large infarct volume in patients taking aspirin before stroke onset.

Association between insufficient medication of antihypertensives and the severity of acute ischemic stroke

Background

Although recent studies have suggested that adherence to antihypertensive treatment reduced stroke incidence, the relationship of adherence to antihypertensives with stroke severity has not been studied. This study attempted to know whether nonadherence before stroke is associated with initial severity of acute ischemic stroke.

Methods

Consecutive patients with acute ischemic stroke were identified in Soonchunhyang University Hospital from Mar 2005 to Aug 2014, excluding the cases without hypertension or information of antihypertensive adherence. We compared the mean of National Institute of Health Stroke Scale (NIHSS) score between adherence groups and insufficient medication group, and additionally in each stroke subtype. Multiple linear regression model was established for initial NIHSS score adjusting alleged factors linked to stroke severity.

Results

Initial NIHSS score were higher in insufficient medication group than adherence group (6.5 ± 7.2 VS 5.4 ± 5.7, P = .11). In large artery atherosclerosis (LAA) and small vessel occlusion (SVO), initial NIHSS score were significantly higher in insufficient medication group (6.1 ± 6.5 VS 4.4 ± 4.4, P = .004 for LAA; 3.8 ± 3.5 VS 2.7 ± 1.8, P = .014 for SVO). In multiple linear regression model, insufficient medication to antihypertensives had a significant effect on NIHSS score (t = 3.417, P = .001) after adjusting covariates.

Conclusion

Insufficient medication of antihypertensives before stroke was independently associated with the severity of acute ischemic stroke. Further studies with prospective designs are warranted to evaluate clinical implication of adherence to antihypertensives for ischemic stroke.

Scientific Rationale for the Inclusion and Exclusion Criteria for Intravenous Alteplase in Acute Ischemic Stroke

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.

The Interplay between Stroke Severity, Antiplatelet Use, and Aspirin Resistance in Ischemic Stroke

BACKGROUND

The issue of whether prior antiplatelet use favorably affects stroke severity is currently unresolved. In this study, we evaluated the effect of antiplatelet use on clinical stroke severity and ischemic lesion volume, and assessed the confounding effect of laboratory-defined aspirin resistance on this relationship.

METHODS

Admission National Institutes of Health Stroke Scale (NIHSS) score, ischemic lesion volumes on diffusion-weighted imaging (DWI), and in vitro aspirin resistance, in addition to other pertinent stroke features, were determined in a series of ischemic stroke patients. Univariate and multivariate analyses were performed to compare clinical and imaging markers of stroke severity among patients with and without prior antiplatelet use, taking into consideration the presence or absence of aspirin resistance.

RESULTS

Antiplatelet users experienced more severe strokes, per NIHSS score, in comparison to antiplatelet-naive patients (P = .007). No significant difference was observed with respect to admission DWI lesion volume. When analyses were repeated after adjustment for stroke subtype and other confounders, no association was observed between antiplatelet use and stroke severity. On the other hand, NIHSS scores were significantly higher in aspirin-unresponsive patients than in both aspirin responders (P = .049) and aspirin nonusers (P = .005).

CONCLUSION

We were unable to demonstrate a substantial positive influence of prestroke antiplatelet usage on stroke severity. Although the presence of more severe strokes among patients with laboratory resistance suggests a protective influence of aspirin sensitivity on stroke severity, the hypothesis could not be validated as no difference was observed among aspirin-naive and aspirin-sensitive patients with respect to admission NIHSS score or DWI lesion volume.

Effect of β-Adrenergic Antagonists on In-Hospital Mortality after Ischemic Stroke

BACKGROUND

Ischemic stroke accounts for 85%-90% of all strokes and currently has very limited therapeutic options. Recent studies of β-adrenergic antagonists suggest they may have neuroprotective effects that lead to improved functional outcomes in rodent models of ischemic stroke; however, there are limited data in patients. We aimed to determine whether there was an improvement in mortality rates among patients who were taking β-blockers during the acute phase of their ischemic stroke.

METHODS

A retrospective analysis of a prospectively collected database of ischemic stroke patients was performed. Patients who were on β-adrenergic antagonists both at home and during the first 3 days of hospitalization were compared with patients who were not on β-adrenergic antagonists to determine the association with patient mortality rates.

RESULTS

The study included a patient population of 2804 patients. In univariate analysis, use of β-adrenergic antagonists was associated with older age, atrial fibrillation, hypertension, and more-severe initial stroke presentation. Despite this, multivariable analysis revealed a reduction in in-hospital mortality among patients who were treated with β-adrenergic antagonists (odds ratio, .657; 95% confidence interval, .655-.658).

CONCLUSIONS

The continuation of home β-adrenergic antagonist medication during the first 3 days of hospitalization after an ischemic stroke is associated with a decrease in patient mortality. This supports the work done in rodent models suggesting neuroprotective effects of β-blockers after ischemic stroke.

Effects of different classes of antihypertensive agents on the outcome of acute ischemic stroke

It is unclear whether antihypertensive treatment before stroke affects acute ischemic stroke severity and outcome. To evaluate this association, the authors studied 482 consecutive patients (age 78.8±6.7 years) admitted with acute ischemic stroke. Stroke severity was assessed at admission with the National Institutes of Health Stroke Scale (NIHSS). The outcome was assessed with rates of adverse outcome (modified Rankin scale at discharge ≥2). Independent predictors of severe stroke (NIHSS ≥16) were female sex and atrial fibrillation. Treatment with diuretics before stroke was associated with nonsevere stroke. At discharge, patients with adverse outcome were less likely to be treated before stroke with β-blockers or with diuretics. Independent predictors of adverse outcome were older age, higher NIHSS at admission, and history of ischemic stroke. Treatment with diuretics before stroke appears to be associated with less severe neurologic deficit in patients with acute ischemic stroke.

Autonomic dysfunction in acute ischemic stroke: an underexplored therapeutic area?

Impaired autonomic function, characterized by a predominance of sympathetic activity, is common in patients with acute ischemic stroke. This review describes methods to measure autonomic dysfunction in stroke patients. It summarizes a potential relationship between ischemic stroke-associated autonomic dysfunction and factors that have been associated with worse outcome, including cardiac complications, blood pressure variability changes, hyperglycemia, immune depression, sleep disordered breathing, thrombotic effects, and malignant edema. Involvement of the insular cortex has been suspected to play an important role in causing sympathovagal imbalance, but its exact role and that of other brain regions remain unclear. Although sympathetic overactivity in patients with ischemic stroke appears to be a negative prognostic factor, it remains to be seen whether therapeutic strategies that reduce sympathetic activity or increase parasympathetic activity might improve outcome.

Safety of thrombolysis in acute ischemic stroke: a review of complications, risk factors, and newer technologies

Intravenous recombinant tissue plasminogen activator (r-tPA) was approved for use in acute ischemic stroke in the United States in 1996. Approximately 2% to 5% of patients with acute ischemic stroke receive r-tPA. Complications related to intravenous r-tPA include symptomatic intracranial hemorrhage, major systemic hemorrhage, and angioedema in approximately 6%, 2%, and 5% of patients, respectively. Risk factors for symptomatic hemorrhage include age, male gender, obesity, increased stroke severity, diabetes, hyperglycemia, uncontrolled hypertension, combination antiplatelet use, large areas of early ischemic change, atrial fibrillation, congestive heart failure, and leukoariosis. A risk factor for angioedema is the use of angiotensin-converting enzyme inhibitor. Risk assessment scores, novel imaging strategies, and telemedicine may offer methods of optimizing the risk-benefit ratio.

Anaemia on Admission is Associated with More Severe Intracerebral Haemorrhage and Worse Outcomes

Background

Lower haemoglobin levels may impair cerebral oxygen delivery and threaten tissue viability in the setting of acute brain injury. Few studies have examined the association between haemoglobin levels and outcomes after spontaneous intracerebral haemorrhage.

Aims

We evaluated whether anaemia on admission was associated with greater intracerebral haemorrhage severity and worse outcome.

Methods

Consecutive patients with spontaneous intracerebral haemorrhage were analyzed from the Registry of the Canadian Stroke Network. Admission haemoglobin was related to stroke severity (using the Canadian Neurological Scale), modified Rankin score at discharge, and one-year mortality. Adjustment was made for potential confounders including age, gender, medical history, warfarin use, glucose, creatinine, blood pressure, and intraventricular haemorrhage.

Results

Two thousand four hundred six patients with intracerebral haemorrhage were studied of whom 23% had anaemia (haemoglobin <120 g/l) on admission, including 4% with haemoglobin <100 g/l. Patients with anaemia were more likely to have severe neurological deficits at presentation [haemoglobin ≤100 g/l, adjusted odds ratio 4·04 (95% confidence interval 2·39, 6·84); haemoglobin 101–120 g/l, adjusted odds ratio 1·93 (95% confidence interval 1·43, 2·59), both P < 0·0001]. In nonanticoagulated patients, severe anaemia was also associated with poor outcome (modified Rankin score 4–6) at discharge [haemoglobin ≤100 g/l, adjusted odds ratio 2·42 (95% confidence interval 1·07–5·47), P= 0·034] and increased mortality at one-year [haemoglobin ≤100 g/l, adjusted hazard ratio 1·73 (95% confidence interval 1·22–2·45), P = 0·002].

Conclusions

Anaemia on admission is associated with greater intracerebral haemorrhage severity and worse outcomes. The utility of transfusion remains unclear in this setting.

Comparative evaluation of treatment with low-dose aspirin plus dipyridamole versus aspirin only in patients with acute ischaemic stroke

BACKGROUND

Previous studies have suggested that pre-stroke treatment with low-dose aspirin (A) could reduce the severity of acute ischaemic stroke, but less is known on the effect of pre-stroke treatment with a combination of aspirin and dipyridamole (A + D) and post-stroke effects of these drugs. The aim of the present study was to evaluate the effect of this drug combination on acute and long-term prognosis of ischaemic stroke.

METHODS

Patients without atrial fibrillation admitted to the stroke unit with acute ischaemic stroke (n = 554) or TIA (n = 108) were studied during acute hospital care and up to 12 months after discharge from hospital.

RESULTS

Prior to acute stroke 62 patients were treated with A + D while 247 patients were treated with A only. No beneficial effects of the combination A + D compared to A only were noted on stroke severity and/or acute in-hospital mortality. However, survival analysis by Cox-proportional hazard model demonstrated lower 12-months all-cause mortality in patients discharged with A + D (n = 275) compared with patients on A only (HR, 0.52; CI, 0.32-0.86; p = 0.011; n = 262) after adjusting for age, baseline NIHSS, previous stroke, previous myocardial infarction and type 2 diabetes. We also noted a tendency towards lower all-cause mortality at 3 months with use of A + D, but this was not statistically significant (p = 0.12).

CONCLUSIONS

Pre-stroke treatment with a combination of low-dose A + D does not reduce the severity of acute stroke, nor does it reduce the acute in-hospital mortality. However, treatment with A + D at discharge from hospital is seemingly associated with lower long-term mortality compared with A only, contrary to the results from previous randomised studies. However, our results must be interpreted with extreme caution considering the non-randomised study design.

Association of statins and statin discontinuation with poor outcome and survival after intracerebral hemorrhage

BACKGROUND AND PURPOSE

Studies suggest a protective role for statins after intracerebral hemorrhage, but many failed to assess statin discontinuation, did not include postdischarge outcomes, or did not account for withdrawal of care. We studied the relationship between preintracerebral hemorrhage statin use and in-hospital statin discontinuation on stroke severity and 30-day mortality.

METHODS

We analyzed data from the Registry of the Canadian Stroke Network and determined the adjusted ORs for statin use and outcomes, controlling for stroke severity and other covariates.

RESULTS

We analyzed 2466 consecutive patients with intracerebral hemorrhage from 2003 to 2008: median age was 71 years, 53.6% were male, and 30-day mortality rate was 36.5%. Overall, 537 (21.7%) were taking statins before presentation. Compared with nonusers, statin users were less likely to have severe strokes on presentation (54.7% versus 63.3%) but had similar rates of poor outcome (70% versus 67%) and 30-day mortality (36% versus 37%). Statins were discontinued on admission in 158 of 537 (29.4%); these patients were more likely to have severe stroke (65% versus 27%, P<0.01), poor outcome (90% versus 62%, P<0.01), and to have died by 30 days (71% versus 21%, P<0.01). After adjusting for stroke severity, statin discontinuation was still associated with poor outcome (adjusted OR, 2.4; 95% CI, 1.13-4.56) and higher mortality (adjusted OR, 2.0; 95% CI, 1.30-3.04). However, these associations were attenuated and no longer significant after excluding patients treated palliatively.

CONCLUSIONS

We found no association between preadmission statin use and outcomes in intracerebral hemorrhage. Statin discontinuation may worsen outcomes or may simply be a marker of worse underlying prognosis.

Pre-stroke use of beta-blockers does not affect ischaemic stroke severity and outcome

BACKGROUND AND PURPOSE

It is unclear whether pre-stroke beta-blockers use may influence stroke outcome. This study evaluates the independent effect of pre-stroke use of beta-blockers on ischaemic stroke severity and 3 months functional outcome.

METHODS

Pre-stroke use of beta-blockers was investigated in 1375 ischaemic stroke patients who had been included in two placebo-controlled trials with lubeluzole. Stroke severity was assessed by either the National Institute of Health Stroke Scale (NIHSS) or the European Stroke Scale (ESS). A modified Rankin scale (mRS) score of >3 at 3 months was used as measure for the poor functional outcome.

RESULTS

Two hundred and sixty four patients were on beta-blockers prior to stroke onset, and 105 patients continued treatment after their stroke. Pretreatment with beta-blockers did not influence baseline stroke severity. There was no difference in stroke severity between nonusers and those on either a selective beta(1)-blocker or a non-selective beta-blocker. The likelihood of a poor outcome at 3 months was not influenced by pre-stroke beta-blocker use or beta-blocker use before and continued after stroke onset.

CONCLUSIONS

  Pre-stroke use of beta-blockers does not appear to influence stroke severity and functional outcome at 3 months.