Prior Antiplatelet Agent Use and Outcomes after Intravenous Thrombolysis with Recombinant Tissue Plasminogen Activator in Acute Ischemic Stroke: A Meta-Analysis of Cohort Studies and Randomized Controlled Trials

Treatment Effects in Randomized and Nonrandomized Studies of Pharmacological Interventions: A Meta-Analysis

Importance

Randomized clinical trials (RCTs) are widely regarded as the methodological benchmark for assessing clinical efficacy and safety of health interventions. There is growing interest in using nonrandomized studies to assess efficacy and safety of new drugs.

Objective

To determine how treatment effects for the same drug compare when evaluated in nonrandomized vs randomized studies.

Data Sources

Meta-analyses published between 2009 and 2018 were identified in MEDLINE via PubMed and the Cochrane Database of Systematic Reviews. Data analysis was conducted from October 2019 to July 2024.

Study Selection

Meta-analyses of pharmacological interventions were eligible for inclusion if both randomized and nonrandomized studies contributed to a single meta-analytic estimate.

Data Extraction and Synthesis

For this meta-analysis using a meta-epidemiological framework, separate summary effect size estimates were calculated for nonrandomized and randomized studies within each meta-analysis using a random-effects model and then these estimates were compared. The reporting of this study followed the Guidelines for Reporting Meta-Epidemiological Methodology Research and relevant portions of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) reporting guideline.

Main Outcome and Measures

The primary outcome was discrepancies in treatment effects obtained from nonrandomized and randomized studies, as measured by the proportion of meta-analyses where the 2 study types disagreed about the direction or magnitude of effect, disagreed beyond chance about the effect size estimate, and the summary ratio of odds ratios (ROR) obtained from nonrandomized vs randomized studies combined across all meta-analyses.

Results

A total of 346 meta-analyses with 2746 studies were included. Statistical conclusions about drug benefits and harms were different for 130 of 346 meta-analyses (37.6%) when focusing solely on either nonrandomized or randomized studies. Disagreements were beyond chance for 54 meta-analyses (15.6%). Across all meta-analyses, there was no strong evidence of consistent differences in treatment effects obtained from nonrandomized vs randomized studies (summary ROR, 0.95; 95% credible interval [CrI], 0.89-1.02). Compared with experimental nonrandomized studies, randomized studies produced on average a 19% smaller treatment effect (ROR, 0.81; 95% CrI, 0.68-0.97). There was increased heterogeneity in effect size estimates obtained from nonrandomized compared with randomized studies.

Conclusions and Relevance

In this meta-analysis of treatment effects of pharmacological interventions obtained from randomized and nonrandomized studies, there was no overall difference in effect size estimates between study types on average, but nonrandomized studies both overestimated and underestimated treatment effects observed in randomized studies and introduced additional uncertainty. These findings suggest that relying on nonrandomized studies as substitutes for RCTs may introduce additional uncertainty about the therapeutic effects of new drugs.

Safety and Efficacy of Baseline Antiplatelet Treatment in Patients Undergoing Mechanical Thrombectomy for Ischemic Stroke: Antiplatelets Before Mechanical Thrombectomy

PURPOSE

To investigate the safety and efficacy of baseline antiplatelet treatment in patients with acute ischemic stroke (AIS) undergoing mechanical thrombectomy (MT).

MATERIALS AND METHODS

Baseline use of antiplatelet medication before MT for (AIS) may provide benefit on reperfusion and clinical outcome but could also carry an increased risk of intracranial hemorrhage (ICH). All consecutive patients with AIS and treated with MT with and without intravenous thrombolysis (IVT) between January 2012 and December 2019 in all centers performing MT nationwide were reviewed. Data were prospectively collected in national registries (eg, SITS-TBY and RES-Q). Primary outcome was functional independence (modified Rankin Scale 0-2) at 3 months; secondary outcome was ICH.

RESULTS

Of the 4,351 patients who underwent MT, 1,750 (40%) and 666 (15%) were excluded owing to missing data from the functional independence and ICH outcome cohorts, respectively. In the functional independence cohort (n = 2,601), 771 (30%) patients received antiplatelets before MT. Favorable outcome did not differ in any antiplatelet, aspirin, and clopidogrel groups when compared with that in the no-antiplatelet group: odds ratio (OR), 1.00 (95% CI, 0.84-1.20); OR, 1.05 (95% CI, 0.86-1.27); and OR, 0.88 (95% CI, 0.55-1.41), respectively. In the ICH cohort (n = 3,685), 1095 (30%) patients received antiplatelets before MT. The rates of ICH did not increase in any treatment options (any antiplatelet, aspirin, clopidogrel, and dual antiplatelet groups) when compared with those in the no-antiplatelet group: OR, 1.03 (95% CI, 0.87-1.21); OR, 0.99 (95% CI, 0.83-1.18); OR, 1.10 (95% CI, 0.82-1.47); and OR, 1.43 (95% CI, 0.87-2.33), respectively.

CONCLUSIONS

Antiplatelet monotherapy before MT did not improve functional independence or increase the risk of ICH.

Sex Differences in Outcomes of Intravenous Thrombolysis in Acute Ischemic Stroke Patients with Preadmission Use of Antiplatelets

AIM

To compare safety and functional outcomes of intravenous thrombolysis (IVT) between females and males with acute ischaemic stroke (AIS) in relation to preadmission use of antiplatelets.

METHODS

Multicentre cohort study of patients admitted from 1 January 2014 to 31 January 2020 to hospitals participating in the Swiss Stroke Registry, presenting with AIS and receiving IVT. Primary safety outcome was in-hospital symptomatic intracerebral haemorrhage (sICH). Primary functional outcome was functional independence at 3 months after discharge. Multivariable logistic regression models were fitted to assess the association between sex and each outcome according to preadmission use of antiplatelets.

RESULTS

The study included 4996 patients (42.51 % females, older than males, median age 79 vs 71 years, p < 0.0001). Comparable proportions of females (39.92 %) and males (40.39 %) used antiplatelets before admission (p = 0.74). In total, 3.06 % females and 2.47 % males developed in-hospital sICH (p = 0.19), with similar odds (adjusted odds ratio, [AOR] 0.93, 95 % confidence interval, [CI] 0.63-1.39). No interaction was found between sex and preadmission use of either single or dual antiplatelets in relation to in-hospital sICH (p = 0.94 and p = 0.23). Males had higher odds of functional independence at 3 months (AOR 1.34, 95 % CI 1.09-1.65), regardless of preadmission use of antiplatelets (interaction between sex and preadmission use of either single or dual antiplatelets p = 0.41 and p = 0.58).

CONCLUSION

No sex differences were observed in the safety of IVT regarding preadmission use of antiplatelets. Males showed more favourable 3-month functional independence than females; however, this sex difference was apparently not explained by a sex-specific mechanism related to preadmission use of antiplatelets.

Effect of prior antiplatelet therapy on large vessel occlusion in patients with non-valvular atrial fibrillation newly initiated on apixaban

INTRODUCTION

We evaluated the effect of prior antiplatelet therapy on large vessel occlusion (LVO) in patients with non-valvular atrial fibrillation (NVAF) newly initiated on apixaban.

METHODS

Patients with acute LVO with acute stroke due to NVAF or stenosis with NVAF started on apixaban within 14 days of onset were enrolled. We compared incidence of major bleeding, cerebral hemorrhage, ischemic events, cerebral infarction, and all-cause mortality between patients with and without prior antiplatelet therapy for acute LVO. We also compared these events between patients who continued antiplatelet therapy after onset (continued group) and those who discontinued it (discontinued group). Hazard ratios were estimated after adjusting for confounders; interaction was evaluated considering intravenous thrombolysis (IVT) or endovascular treatment (EVT) according to major bleeding.

RESULTS

The study comprised 686 eligible patients (excluded [n = 194]; enrolled [n = 492]). The antiplatelet group consisted of older patients (mean: 79 vs. 76 years; p = 0.006) and had a higher cumulative incidence of major bleeding (7.3% vs. 2.9%, p = 0.003). The incidence of ischemic events and all-cause mortality was similar between the groups. Among the 109 patients in the antiplatelet group, the cumulative incidence of major bleeding, ischemic events, and all-cause mortality was comparable between continued group (n = 26) and discontinued group (n = 83). There were no significant differences between groups with and without IVT/EVT. However, major bleeding occured more frequently in the antiplatelet group without IVT.

CONCLUSION

Prior antiplatelet therapy for LVO in patients with NVAF newly initiated on apixaban was associated with major bleeding, which was more frequent in the antiplatelet group without IVT.

Antiplatelet therapy and outcomes following endovascular therapy for acute ischemic stroke: A systemic review and meta-analysis

OBJECTIVE

The outcomes of antiplatelet therapy (APT) in patients with acute ischemic stroke (AIS) receiving endovascular therapy (EVT) remains controversial. Thus, we sought to make a systematic review and meta-analysis of recent clinical trials to confirm the safety and efficacy of APT.

METHODS

All of clinical trails were systematically retrieved from PubMed, Embase and Cochrane. The endpoints or main outcome measures included symptomatic intracranial hemorrhage (sICH), 3-month mortality, successful recanalisation (SR) and 3-month functional independence (FI). Odd ratios (ORs) with their 95% confidence intervals (CIs) were calculated to synthesize effect size by using random-effects models. Sensitivity analysis was performed via calculation of rest data owiting one by one.

RESULTS

23 articles were included after screening. APT as an adjunct to EVT was associated with a higher likelihood of pooled successful recanalisation (OR 1.46, 95% CI 1.07-2.00) and 3-month FI (OR 1.24, 95% CI 1.01-1.51), no associated with sICH and 3-month mortality. However, Sensitivity analysis indicated that the association between APT and SR and 3-month FI were unstable. For patients with prior use of APT or receiving intravenous thrombolysis before EVT, no associated were found between APT and all of endpoints above.

CONCLUSION

Although adjuvant APT appears to increase the number of SR and 3-month FI, the results were unstable. Randomised controlled trials are needed to confirm the efficacy.

Safety and efficacy of antiplatelet use before intravenous thrombolysis for acute Ischemic stroke

AIM

To study the effects of pretreatment with Antiplatelet (AP) before IV thrombolysis (IVT) on the rate of symptomatic intracranial hemorrhage (sICH) and functional outcome in patients with Acute Ischemic stroke (AIS).

METHOD

In this retrospective study, the medical records and cerebrovascular images of all the patients who received IVT for AIS in our center in a 9.6-year period were reviewed. Patients who took at least one dose of any APs in the last 24 h prior to IVT were identified. They were categorized according to the type of AP, single versus dual AP therapy (DAPT), and dose of AP. Rate of sICH and functional outcome at discharge were compared between the AP users and non-users.

RESULTS

A total of 834 patients received IVT for AIS in our center during a 9.6- year period. Multivariate models were adjusted for age, NIHSS on admission, history of atrial fibrillation, history of hypertension, INR on admission, history of stroke and diabetes mellitus. In multivariate regression analyses and after adjusting for the variables mentioned above, the use of any AP was not associated with an increased rate of sICH (OR = 1.28 [0.70-2.34], p = 0.425). Furthermore, the use of DAPT did not significantly increase the rate of sICH in multivariate regression analyses. (OR = 0.663 [0.15-2.84], p = 0.580). The patients on any AP had a lower chance of having good functional outcome in univariate analysis (OR = 0.735 [0.552-0.979], p = 0.035). However, when adjusted for age, baseline NIHSS, history of diabetes, hypertension and prior stroke, AP use was not associated with a decreased chance of having a good functional outcome at discharge. (OR = 0.967 [0.690-1.357], p = 0.848). In addition, no significant difference was noted in the rate of good functional outcome between patients on DAPT and no AP users in multivariate regression analyses. (OR = 1.174 [0.612-2.253], p = 0.629).

CONCLUSION

Our study did not show any significant association between the risk of sICH and good functional outcome after IVT for AIS patients on AP therapy (dual or single) in comparison with AP naïve patients.

European Stroke Organisation (ESO) guidelines on intravenous thrombolysis for acute ischaemic stroke

Intravenous thrombolysis is the only approved systemic reperfusion treatment for patients with acute ischaemic stroke. These European Stroke Organisation (ESO) guidelines provide evidence-based recommendations to assist physicians in their clinical decisions with regard to intravenous thrombolysis for acute ischaemic stroke. These guidelines were developed based on the ESO standard operating procedure and followed the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) methodology. The working group identified relevant clinical questions, performed systematic reviews and meta-analyses of the literature, assessed the quality of the available evidence, and wrote recommendations. Expert consensus statements were provided if not enough evidence was available to provide recommendations based on the GRADE approach. We found high quality evidence to recommend intravenous thrombolysis with alteplase to improve functional outcome in patients with acute ischemic stroke within 4.5 h after symptom onset. We also found high quality evidence to recommend intravenous thrombolysis with alteplase in patients with acute ischaemic stroke on awakening from sleep, who were last seen well more than 4.5 h earlier, who have MRI DWI-FLAIR mismatch, and for whom mechanical thrombectomy is not planned. These guidelines provide further recommendations regarding patient subgroups, late time windows, imaging selection strategies, relative and absolute contraindications to alteplase, and tenecteplase. Intravenous thrombolysis remains a cornerstone of acute stroke management. Appropriate patient selection and timely treatment are crucial. Further randomized controlled clinical trials are needed to inform clinical decision-making with regard to tenecteplase and the use of intravenous thrombolysis before mechanical thrombectomy in patients with large vessel occlusion.

Low dosis of alteplase, for ischemic stroke after Enchanted and its determinants, a single center experience

BACKGROUND

Low-dose alteplase (LrtPA) has been shown not to be inferior to the standard-dose (SrtPA) with respect to death/disability.

OBJECTIVE

We aim to evaluate the percentage of patients treated with LrtPA at our center after the ENCHANTED trial and the factors associated with the use of this dosage.

METHODS

Prospective study in consecutive patients with an acute stroke admitted between June 2016 and November 2018.

RESULTS

160 patients were treated with intravenous thrombolysis, 50% female; mean age 65.4±18.5 years. Of these, 48 patients (30%) received LrtPA. In univariate analysis, LrtPA was associated with patient's age (p=0.000), previous modified Rankin scale scores (mRS) (p<0.000), hypertension (p=0.076), diabetes mellitus (p=0.021), hypercholesterolemia (p=0.19), smoking (p=0.06), atrial fibrillation (p=0.10), history of coronary artery disease (p=0.06), previous treatment with antiplatelet agents (p<0.000), admission International Normalized Ratio-INR (p=0.18), platelet count (p=0.045), leukoaraiosis on neuroimaging (p<0.003), contraindications for thrombolytic treatment (p=0.000) and endovascular treatment (p=0.027). Previous relevant bleedings were determinants for treatment with LrtPA. Final diagnosis on discharge of stroke mimic was significant (p=0.02) for treatment with SrtPA. In multivariate analysis, mRS (OR: 2.21; 95%CI 1.37‒14.19), previous antiplatelet therapy (OR: 11.41; 95%CI 3.98‒32.70), contraindications for thrombolysis (OR: 56.10; 95%CI 8.81‒357.80), leukoaraiosis (OR: 4.41; 95%CI 1.37‒14.10) and diagnosis of SM (OR: 0.22; 95%CI 0.10‒0.40) remained independently associated.

CONCLUSIONS

Following the ENCHANTED trial, LrtPA was restricted to 30% of our patients. The criteria that clinicians apply are based mostly on clinical variables that may increase the risk of brain or systemic hemorrhage or exclude the patient from treatment with lytic drugs.

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.

Dual Antiplatelet Therapy Increases Hemorrhagic Transformation Following Thrombolytic Treatment in Experimental Stroke

Background and Purpose- Dual antiplatelet treatment poses a risk for increased hemorrhagic transformation (HT) following intravenous thrombolysis and mechanical thrombectomy. The aim of this study was to implement a model of experimental stroke with tissue-type plasminogen activator (tPA)-associated HT in mice on dual antiplatelet treatment to enable mechanistic studies and also to allow for an initial assessment of therapeutic approaches to limit HT. Methods- Male C57BL6 mice were fed with Aspirin and Clopidogrel via drinking water for 3 days. Subsequently, mice were subjected to 2-hour transient middle cerebral artery occlusion, and tPA was infused when indicated. HT was quantified by measuring hemorrhaged areas in brain sections with ImageJ. TTC staining was used to determine infarct size. Platelet function was tested in vitro using flow cytometry and in vivo with standard tail bleeding tests. Results- Both flow cytometry and tail bleeding volumes indicated significantly reduced platelet function following Aspirin and Clopidogrel treatment. While tPA administered 2 hours after onset of middle cerebral artery occlusion did not cause bleeding in control mice (0.51±0.13 mm2), HT significantly increased by 18.9±5.4 mm2 (P=0.0045) in Aspirin and Clopidogrel mice treated with tPA. HT in aspirin and clopidogrel mice not treated with tPA was nonsignificantly elevated by 8.0±4.6 mm² (P=0.3784) compared with controls. Infarct sizes did not differ between groups. The HT persisted when the tPA dosage was reduced. Conclusions- We successfully established a translational stroke model of tPA treatment under dual antiplatelet treatment. The impaired platelet function led to an increased risk for HT in tPA-treated mice. Reducing the dosage of tPA did not prevent this hemorrhagic complication.

Futile reperfusion and predicted therapeutic benefits after successful endovascular treatment according to initial stroke severity

Background

Futile reperfusion (poor functional status despite successful reperfusion) was observed in up to 67% of patients enrolled in recent endovascular treatment (EVT) clinical trials. We investigated the impact of baseline stroke severity on both futile reperfusion and therapeutic benefit of successful EVT.

Methods

Using a prospective multicenter stroke registry, we identified consecutive ischemic stroke patients with anterior circulation large artery occlusion, who were reperfused successfully by EVT (Thrombolysis in Cerebral Infarction grade 2b–3). The rate of futile reperfusion was assessed across the initial National Institutes of Health Stroke Scale (NIHSS) scores. The frequency of poor outcomes (modified Rankin scale [mRS] 3–6) according to NIHSS scores was compared between patients revascularized successfully by EVT and those who did not receive EVT, after standardizing for age.

Results

Among 21,591 patients with ischemic stroke, 972 (4.5%) received EVT within 12 h of onset, including 440 who met study eligibility criteria. Futile reperfusion was observed in 226 of the 440 study-eligible patients (51.4%) and was associated with stroke severity: 20.9% in NIHSS scores ≤5, 34.6% in 6–10, 58.9% in 11–20, and 63.8% in > 20 (p < 0.001). Nonetheless, the therapeutic benefit of EVT also increased with increasing stroke severity (p for interaction < 0.001): 0.1% in NIHSS ≤5, 18.6% in 6–10, 28.7% in 11–20, and 34.3% in > 20.

Conclusions

EVT is more beneficial with increasing stroke severity, although futile reperfusion also increases with higher stroke severity.

Electronic supplementary material

The online version of this article (10.1186/s12883-019-1237-2) contains supplementary material, which is available to authorized users.

Intravenous thrombolysis for acute ischemic stroke: a bridge between two centuries

INTRODUCTION

Intravenous tissue-plasminogen activator (tPA) remains the only approved systemic reperfusion therapy suitable for most patients presenting timely with acute ischemic stroke. Accumulating real-word experience for over 20 years regarding tPA safety and effectiveness led to re-appraisal of original contraindications for intravenous thrombolysis (IVT). Areas covered: This narrative review focuses on fast yet appropriate selection of patients for safe administration of tPA per recently expanded indications. Novel strategies for rapid patient assessment will be discussed. The potential for mobile stroke units (MSU) that shorten onset-to-needle time and increase tPA treatment rates is addressed. The use of IVT in the era of non-vitamin K antagonist oral anticoagulants (NOACs) is highlighted. The continuing role of IVT in large vessel occlusion (LVO) patients eligible for mechanical thrombectomy (MT) is discussed with regards to 'drip and ship' vs. 'mothership' treatment paradigms. Promising studies of penumbral imaging to extend IVT beyond the 4.5-hour window and in wake-up strokes are summarized. Expert commentary: This review provides an update on the role of IVT in specific conditions originally considered tPA contraindications. Novel practice challenges including NOAC's, MSU proliferation and bridging therapy (IVT&MT) for LVO patients, and the potential extension of IVT time-window using penumbral imaging are emerging as safe and potentially effective IVT applications.

Challenges in the Anesthetic and Intensive Care Management of Acute Ischemic Stroke

Acute ischemic stroke (AIS) is a devastating condition with high morbidity and mortality. In the past 2 decades, the treatment of AIS has been revolutionized by the introduction of several interventions supported by class I evidence-care on a stroke unit, intravenous tissue plasminogen activator within 4.5 hours of stroke onset, aspirin commenced within 48 hours of stroke onset, and decompressive craniectomy for supratentorial malignant hemispheric cerebral infarction. There is new class I evidence also demonstrating benefits of endovascular therapy on functional outcomes in those with anterior circulation stroke. In addition, the importance of the careful management of key systemic physiological variables, including oxygenation, blood pressure, temperature, and serum glucose, has been appreciated. In line with this, the role of anesthesiologists and intensivists in managing AIS has increased. This review highlights the main challenges in the endovascular and intensive care management of AIS that, in part, result from the paucity of research focused on these areas. It also provides guidelines for the management of AIS based upon current evidence, and identifies areas for further research.

Ultrasound-facilitated, catheter-directed, low-dose fibrinolysis in elderly patients with pulmonary embolism: A SEATTLE II sub-analysis

Elderly patients with acute pulmonary embolism (PE) have higher mortality than non-elderly patients, but receive systemic fibrinolysis less frequently. In this sub-analysis of the SEATTLE II trial, we evaluated the efficacy and safety of ultrasound-facilitated, catheter-directed, low-dose fibrinolysis in elderly patients with submassive and massive PE. We compared patients ⩾65 years old with those <65 years old. Eligible patients had proximal PE and a right ventricular-to-left ventricular (RV/LV) diameter ratio ⩾0.9 on chest computed tomography (CT). The primary efficacy outcome was the change in chest CT-measured RV/LV diameter ratio at 48 hours after procedure initiation. The primary safety outcome was major bleeding within 72 hours. Sixty-two patients were ⩾65 years of age and 88 were <65 years of age. The RV/LV diameter ratio decreased in both groups 48 hours post-procedure, with a mean change of −0.47 in those ⩾65 and −0.39 in those <65 years old, with no difference between groups ( p = 0.31). Major bleeding occurred in nine (15%) of those ⩾65 and in six (7%) of those <65 years old ( p = 0.17). Ultrasound-facilitated, catheter-directed, low-dose fibrinolysis resulted in a similar reduction in RV/LV diameter ratio in elderly patients with massive and submassive PE compared with non-elderly patients.

Prestroke Antiplatelet Effect on Symptomatic Intracranial Hemorrhage and Functional Outcome in Intravenous Thrombolysis

Background and Purpose

About 30%-40% of stroke patients are taking antiplatelet at the time of their strokes, which might increase the risk of symptomatic intracranial hemorrhage (SICH) with intravenous tissue plasminogen activator (IV-TPA) therapy. We aimed to assess the effect of prestroke antiplatelet on the SICH risk and functional outcome in Koreans treated with IV-TPA.

Methods

From a prospective stroke registry, we identified patients treated with IV-TPA between October 2009 and November 2014. Prestroke antiplatelet use was defined as taking antiplatelet within 7 days before the stroke onset. The primary outcome was SICH. Secondary outcomes were discharge modified Rankin Scale (mRS) score and in-hospital mortality.

Results

Of 1,715 patients treated with IV-TPA, 441 (25.7%) were on prestroke antiplatelet. Prestroke antiplatelet users versus non-users were more likely to be older, to have multiple vascular risk factors. Prestroke antiplatelet use was associated with an increased risk of SICH (5.9% vs. 3.0%; adjusted odds ratio [OR] 1.79 [1.05-3.04]). However, at discharge, the two groups did not differ in mRS distribution (adjusted OR 0.90 [0.72-1.14]), mRS 0-1 outcome (34.2% vs. 33.7%; adjusted OR 1.27 [0.94-1.72), mRS 0-2 outcome (52.4% vs. 52.9%; adjusted OR 1.21 [0.90-1.63]), and in-hospital mortality (6.1% vs. 4.2%; adjusted OR 1.19 [0.71-2.01]).

Conclusions

Despite an increased risk of SICH, prestroke antiplatelet users compared to non-users had comparable functional outcomes and in-hospital mortality with IV-TPA therapy. Our results support the use of IV-TPA in eligible patients taking antiplatelet therapy before their stroke onset.

Intravenous Thrombolysis for Acute Ischemic Stroke in Patients Receiving Antiplatelet Therapy: A Systematic Review and Meta-analysis of 19 Studies

BACKGROUND

The safety and long-term outcome of systemic thrombolysis in patients receiving antiplatelet medications remain subjects of great clinical significance. The objective of this meta-analysis was to determine how prestroke antiplatelet therapy affects the risks and benefits of intravenous thrombolysis in patients with acute ischemic stroke.

METHODS AND RESULTS

A dual-reviewer search was conducted in PubMed and EMBASE databases through November 2015, from which 19 studies involving a total of 108 588 patients with acute ischemic stroke were identified based on preset inclusion criteria. Information on study designs, patient characteristics, exposures, outcomes, and adjusting confounders was extracted, and estimates were combined by using random-effects models. The pooled crude estimates suggested that taking long-term antiplatelet medications was associated with higher odds of symptomatic intracranial hemorrhage (odds ratio [OR] 1.70, 95% CI 1.47-1.97) and death (OR 1.46, 95% CI 1.22-1.75) and lower odds of favorable functional outcomes (OR 0.86, 95% CI 0.80-0.93). However, the combined confounder-adjusted results only confirmed a relatively weak positive association between prior antiplatelet therapy and symptomatic intracranial hemorrhage (OR 1.21, 95% CI 1.02-1.44) and demonstrated no significant relationship between antiplatelet therapy and the other 2 outcomes (favorable outcome OR 1.09, 95% CI 0.96-1.24; death OR 1.02, 95% CI 0.98-1.07). Subgroup analyses revealed that the associations between prestroke antiplatelet therapy and outcomes were dependent on time and antiplatelet agents.

CONCLUSIONS

Patients with acute ischemic stroke receiving long-term antiplatelet medications were associated with greater risks of developing symptomatic intracranial hemorrhage after systemic thrombolysis. However, the overall independent association between prestroke antiplatelet therapy and unfavorable outcomes or mortality was insignificant.

Comparative Efficacy and Safety of Nine Anti-Platelet Therapies for Patients with Ischemic Stroke or Transient Ischemic Attack: a Mixed Treatment Comparisons

Anti-platelet treatments, an effective anti-thrombotic therapy, are widely used in non-cardioembolic ischemic stroke or transient ischemic attack (TIA), including aspirin, cilostazol, clopidogrel, and other mono or dual therapies, while the optimal choice remains uncertain. All the literatures of 38 eligible randomized control trials were searched in PubMed, Embase, and China National Knowledge Internet (CNKI) without language limitation. And, nine anti-platelet therapies were assessed, including aspirin, clopidogrel, cilostazol, ticlopidine, triflusal, terutroban, sarpogrelate, dipyridamole plus aspirin, and clopidogrel plus aspirin. Additionally, we extract data of composite vascular events, major bleeding, ischemic stroke, intracranial hemorrhage, and all-cause death, as indicators of efficacy and safety. And among them, composite vascular events were the primary outcome. The binary outcomes were expressed as odds ratios (ORs) with corresponding 95 % confidence intervals (CIs). Both traditional meta-analysis and network meta-analysis were performed. Besides, for each outcome, the rank order was applied to reflect the superiority of every therapy compared with others, using the surface under the cumulative ranking curve (SUCRA). A cluster analysis was also conducted. Through the network meta-analysis, the synthesized data shows that cilostazol performed best on composite vascular events compared with placebo (OR = 0.62, 95 % CI 0.46-0.83) and aspirin (OR = 0.71, 95 % CI 0.53-0.95). In terms of ischemic stroke, clopidogrel plus aspirin seems the optimal, and it has significant difference between placebo (OR = 0.53, 95 % CI 0.35-0.74) and aspirin (OR = 0.75, 95 % CI 0.61-0.95). Meanwhile, cilostazol is also the first rank in major bleeding, especially when it is in contrast to aspirin (OR = 0.13, 95 % CI 0.02-0.70) and clopidogrel plus aspirin (OR = 0.09, 95 % CI 0.01-0.50). There is no significant difference among these nine treatments and placebo, as to all-cause death and intracranial hemorrhage. According to the cluster analysis, cilostazol can be the best choice with comprehensive assessment of composite vascular events, ischemic stroke and major bleeding. Based on this network meta-analysis, cilostazol was recommended as the optimal choice with good performance in both efficacy and safety for patient with ischemic stroke or TIA among nine anti-platelet therapies.