Dual antiplatelet therapy may increase the risk of non-intracranial haemorrhage in patients with minor strokes: a subgroup analysis of the CHANCE trial

Dual antiplatelet therapy versus intravenous tissue plasminogen activator with acute minor ischemic stroke: A systematic review and meta-analysis of safety and efficacy

OBJECTIVES

To compare the safety and efficacy of Dual Antiplatelet Therapy (DAPT) and Intravenous (IV) Tissue Plasminogen Activator (t-PA) in minor Acute Ischemic Stroke (AIS).

MATERIALS AND METHODS

Following Cochrane and PRISMA guidelines, we analyzed observational studies and clinical trials comparing DAPT and IV t-PA in patients with minor AIS. Databases included PubMed, Scopus, and Web of Science. Data extraction included study characteristics, patient demographics, and analyzed outcomes. RevMan 5.3 and OpenMetaAnalyst 2021 were used to analyze the data and assess heterogeneity, respectively. The risk of bias was determined using RoB 2.0 and the Newcastle-Ottawa scale.

RESULTS

This meta-analysis included five studies with 3,978 DAPT-treated patients and 2,224 IV t-PA-treated patients. We found no significant differences in achieving modified Rankin scale (mRS) scores of 0-1 (OR 1.11, 95 % CI: 0.79, 1.55, p = 0.56) and 0-2 (OR 0.90, 95 % CI: 0.61, 1.31, p = 0.57), as well as combined mRS scores (OR 1.05, 95 % CI: 0.82, 1.34, p = 0.72). Similarly, there were no significant disparities between the two treatment groups in NIHSS score change from baseline (MD 0.32, 95 % CI: -0.35, 0.98, p = 0.35) and in mortality rates (OR 0.87, 95 % CI: 0.26, 2.93, p = 0.83). Notably, in comparison to the IV t-PA group, the DAPT group exhibited a significantly lower incidence of bleeding (OR 0.31, 95 % CI: 0.14, 0.69, p = 0.004) and symptomatic intracranial hemorrhage (sICH) (OR 0.10, 95 % CI: 0.04, 0.26, p < 0.00001).

CONCLUSIONS

Our meta-analysis found no significant differences in efficacy between DAPT and IV t-PA. However, DAPT demonstrated a significantly lower risk of sICH and bleeding compared with IV t-PA.

Comparison of Effectiveness and Safety of Dual Antiplatelet Therapy (DAPT) With Clopidogrel and Aspirin Versus Aspirin Monotherapy in Patients With Mild-to-Moderate Stroke and Transient Ischemic Attack: A Systematic Review and Meta-Analysis

The aim of this meta-analysis was to assess the effectiveness and safety of the combination of clopidogrel and aspirin in patients with mild ischemic stroke or transient ischemic attack (TIA). The methodologies employed in this meta-analysis strictly followed the commonly used reporting formats for systematic reviews and meta-analyses. The methodologies employed in this meta-analysis strictly followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Until March 25, 2024, we conducted thorough searches on PubMed, EMBASE (Excerpta Medica Database), and the Cochrane Library to locate studies investigating the efficacy and safety of dual antiplatelet therapy (DAPT) in patients with mild or moderate stroke or TIA. Outcomes assessed in this meta-analysis included stroke (including ischemic stroke and hemorrhagic stroke), myocardial infarction, all bleeding events, and moderate to severe bleeding events. A total of 12 studies were included in this meta-analysis. The total number of enrolled patients across these studies was 35,369, with 16,957 receiving DAPT and 18,412 receiving aspirin monotherapy. The risk of developing stroke was significantly lower in patients receiving the combination of clopidogrel and aspirin compared to the aspirin monotherapy group (relative risk (RR): 0.77, 95% confidence interval (CI): 0.72 to 0.83, p-value<0.0001). No significant differences were there in terms of all bleeding events (RR: 1.37, 95% CI: 0.92 to 2.04, p-value: 0.12) and moderate to severe bleeding events (RR: 1.18, 95% CI: 0.86 to 1.63, p-value: 0.30). These findings highlight the importance of carefully weighing the potential benefits against the risks, especially in clinical decision-making for patients with TIA or ischemic stroke. Further research is warranted to elucidate optimal strategies for balancing stroke prevention with bleeding risk mitigation in this patient population.

Comparison of Cilostazol versus Clopidogrel in Addition to Aspirin in Patients with Ischemic Stroke who Underwent Intracranial or Extracranial Artery Stent Implantation

AIMS

The role of cilostazol after intracranial or extracranial artery stent implantation is still unclear. Therefore, we designed this trial to explore the efficacy and safety of cilostazol in this particular population.

METHODS

In this retrospective study, patients were divided into the cilostazol or clopidogrel group by the antiplatelet therapy received after artery stent implantation. The primary efficacy endpoint was ischemic stroke. Bleeding events and other antiplatelet drug-related adverse reactions (ADRs) were also recorded. Neurological function prognosis was evaluated by the modified Rankin Scale (mRS) after discharge.

RESULTS

A total of 156 patients were enrolled; 56 underwent intracranial artery stenting, 95 underwent extracranial artery stenting, and 5 underwent intracranial combined with extracranial artery stenting. Any stroke and bleeding events in the hospital of the two groups were comparable (P=0.38, P=0.34, respectively). The incidence of stroke recurrence tended to be lower in the cilostazol group, although not significant (cilostazol vs. clopidogrel, 1.35% vs. 4.88%, P=0.25). There was a significant difference of any bleeding events between the two groups (cilostazol vs. clopidogrel, 5.41% vs. 20.73%, P=0.02). During follow-up, we did not observe an apparent increase of ADRs in the cilostazol group (cilostazol vs. clopidogrel, palpitation 4.05% vs. 2.44%, P=0.58; gastrointestinal discomfort events 8.11% vs. 12.20%, P=0.80). There were no differences between the two groups of neurological function prognosis (P=0.29).

CONCLUSIONS

Cilostazol-based dual antiplatelet therapy could be recommended as an effective and safe therapy regimen among patients undergoing intracranial or extracranial artery stent implantation.

A comparison of safety and efficacy between long-term DAPT and intensive statins combined with short-term DAPT for acute ischemic stroke

OBJECTIVES

The current study compared the safety and efficacy of long-term dual antiplatelet therapy (DAPT, aspirin plus clopidogrel) and intensive rosuvastatin with short-term DAPT for acute ischemic stroke (AIS).

METHODS

A total of 220 patients were enrolled 72 h after the onset of mild to moderate AIS, and divided into a control group treated with 21-day DAPT and a study group treated with intensive rosuvastatin with 7-day DAPT on a voluntary basis. The primary outcome was recurrent ischemic stroke and hemorrhage during a 90-day follow-up period in an intention-to-treat analysis. The secondary outcome was clinical efficacy with respect to alleviating existing focal nerve defect symptoms. A Cox proportional-hazards model was used to evaluate treatment differences.

RESULTS

Clinical efficacy was evident in 87.3% of patients in the study group, compared with 84.3% in the control group (p = 0.042). Recurrent ischemic stroke occurred in 9 patients (7.6%) in the study group and in 9 (8.8%) in the control group (p = 0.767). Hemorrhage occurred in 6 patients (5.1%) in the study group and in 15 (14.7%) in the control group (p = 0.023). In comparisons of levels of ALT, AST, LDH, and CK in the two groups before and 2 weeks after therapy, only CK differed significantly (p < 0.001).

CONCLUSIONS

Compared to long-term DAPT, intensive rosuvastatin with short-term DAPT was equivalent in reducing the risk of recurrent ischemic stroke. It alleviated symptoms more rapidly, and significantly reduced the risk of bleeding, without causing an increase in transaminase or muscle enzymes.

CLINICAL TRIAL REGISTRATION

China Clinical Trial Registration Center (ChiCTR1800017809).

Evaluation and subgroup analysis of the efficacy and safety of intensive rosuvastatin therapy combined with dual antiplatelet therapy in patients with acute ischemic stroke

OBJECTIVES

We investigated the efficacy of intensive rosuvastatin therapy plus 7-day dual antiplatelet therapy (DAPT) in reducing stroke recurrence for patients with acute ischemic stroke (AIS) and compared subgroups of patients.

METHODS

We enrolled patients with AIS whose time of onset to medication was ≤ 72 h, and the baseline scores of NIHSS (bNIHSS) were 0-10. The patients received intensive rosuvastatin therapy plus 7-day DAPT with aspirin and clopidogrel (study group) or rosuvastatin plus single antiplatelet therapy (SAPT, control group). The primary outcomes were recurrence of ischemic stroke, bleeding, statin-induced liver injury, and statin-associated myopathy (SAM) within 90 days. We also performed a subgroup analysis to assess the heterogeneity of the two therapy regimens in reducing recurrent stroke.

RESULTS

Recurrent stroke occurred in 10 patients in the study group and 42 patients in the control group (hazard ratio [HR], 0.373, 95% confidence interval [CI], 0.178-0.780; P = 0.009). Bleeding events occurred in 9 patients in the study group and 14 patients in the control group (HR, 1.019; 95%CI, 0.441-2.353; P = 0.966). Statin-induced liver injury and SAM were not recorded. Intensive rosuvastatin plus 7-day DAPT was generally effective in reducing the risk of recurrent stroke, except in the subgroup with bNIHSS ≤ 2. The therapy was particularly efficient in the elderly, male, high-bNIHSS, and hypertension, diabetes, and hyperlipidemia subgroups, with P < 0.02.

CONCLUSIONS

Without increasing bleeding and statin-associated adverse events, intensive rosuvastatin therapy plus 7-day DAPT significantly reduced the risk of recurrent stroke, especially for subgroups with high-risk factors.

CLINICAL TRIAL REGISTRATION

China Clinical Trial Registration Center (ChiCTR1800017809).

Safety and efficacy of short-term dual antiplatelet therapy combined with intensive rosuvastatin in acute ischemic stroke

OBJECTIVE

To investigate the safety and efficacy of short-term (7-day) Dual Antiplatelet Therapy (DAPT) with intensive rosuvastatin in Acute Ischemic Stroke (AIS).

METHODS

In this study, patients with AIS in the emergency department of the hospital from October 2016 to December 2019 were registered and divided into the control group (Single Antiplatelet Therapy [SAPT] + rosuvastatin) and the study group (7-day DAPT + intensive rosuvastatin) according to the therapy regimens. The generalized linear model was used to compare the National Institute of Health Stroke Scale (NIHSS) scores between the two groups during the 21-day treatment. A Cox regression model was used to compare recurrent ischemic stroke, bleeding events, Statin-Induced Liver Injury (SILI), and Statin-Associated Myopathy (SAM) between the two groups during the 90-day follow-up.

RESULTS

Comparison of NIHSS scores after 21-day treatment: NIHSS scores in the study group decreased significantly, 0.273-times as much as that in the control group (Odds Ratio [OR] 0.273; 95% Confidence Interval [95% CI] 0.208-0.359; p < 0.001). Comparison of recurrent ischemic stroke during the 90-day follow-up: The therapy of the study group reduced the risk of recurrent stroke by 65% (7.76% vs. 22.82%, Hazard Ratio [HR] 0.350; 95% CI 0.167-0.730; p = 0.005). Comparison of bleeding events: There was no statistical difference between the two groups (7.79% vs. 6.71%, HR = 1.076; 95% CI 0.424-2.732; p = 0.878). No cases of SILI and SAM were found.

CONCLUSIONS

Short-term DAPT with intensive rosuvastatin effectively relieved the clinical symptoms and significantly reduced the recurrent stroke for patients with mild-to-moderate AIS within 90 days, without increasing bleeding events, SILI and SAM.

Dual Antiplatelet Therapy in the Management of Acute Minor Ischemic Stroke and High-Risk Transient Ischemic Attack: An Expert Consensus Statement From Taiwan Stroke Society and Taiwan Society of Emergency Medicine

The aim of this review is to achieve a consensus between Taiwan Stroke Society (TSS) and Taiwan Society of Emergency Medicine (TSEM) to manage acute non-cardioembolic minor ischemic stroke (MIS) and high-risk transient ischemic attack (TIA). The methodology is to review the recent findings from clinical trials of dual antiplatelet therapy (DAPT) from 2010 to 2021 and updates in clinical practice guidelines from 2018 to 2022 for non-cardioembolic MIS/TIA management at the acute stage. Four leading clinical studies, CHANCE, POINT, THALES, and CHANCE-2 along with other relevant studies introducing DAPT, are discussed in this review. The risk-benefit profile between stroke recurrence reduction and major bleeding increase is also elucidated. TSS and TSEM concluded that for patients presenting with non-cardioembolic MIS or high-risk TIA who did not receive intravenous alteplase, initiation of DAPT within 24 hours after stroke onset and continued up to 21 days, followed by antiplatelet monotherapy, is effective in reducing recurrent ischemic stroke for a period of up to 90 days.

Factors affecting physician decision-making regarding antiplatelet therapy in minor ischemic stroke

Purpose

To identify the most important factors affecting physician decision-making regarding antiplatelet therapy.

Methods

We retrospectively gathered data from minor ischemic stroke patients with NIHSS scores ≤ 5 within 72 h of onset from 2010 to 2018. The population was divided into four groups by initial antiplatelet therapy: aspirin monotherapy (AM), dual antiplatelet therapy with aspirin and a loading dose of clopidogrel (clopidogrel loading dose of 300 mg on the first day; DAPT-ALC), dual antiplatelet therapy with aspirin and no loading dose of clopidogrel (clopidogrel 75 mg daily, no loading dose; DAPT-AUC), and clopidogrel monotherapy (CM).

Results

In total, 1,377 patients were included in the analysis (excluding patients who accepted thrombolytic drugs, participated in other clinical trials, or had not used antiplatelet drugs). The mean ± S.D. age was 62.0 ± 12.7 years; 973 (70.7%) patients were male. The four groups were AM (n = 541, 39.3%), DAPT-ALC (n = 474, 34.4%), DAPT- AUC (n = 301, 21.9%), and CM (n = 61, 4.4%). Patients receiving antiplatelet monotherapy were older than those receiving dual antiplatelet therapy (63.7–65.7 vs. 59.6–61.4 years), and the median initial systolic blood pressure level was higher in the DAPT-ALC group than in the other groups (all P < 0.05). Patients under 75 years old with an admission SBP lower than 180 mmHg, a history of AM, coronary heart disease, no history of intracerebral hemorrhage, stroke onset occurring after guideline recommendations were updated (the year of 2015), onset-to-arrival time within 24 h, and initial NIHSS score ≤ 3 were more likely to take DAPT-ALC than AM. Compared with DAPT-ALC, DAPT-AUC was associated with an initial SBP level lower than 180 mmHg, a history of smoking, hypertension, no history of ICH, previous treatment with antihypertensives, and onset year after the recommendations were updated.

Conclusions

Many factors affect doctors' decisions regarding antiplatelet therapy, especially guidelines, age, admission SBP level, and hypertensive disease.

Antiplatelet agents for chronic kidney disease

BACKGROUND

Antiplatelet agents are widely used to prevent cardiovascular events. The risks and benefits of antiplatelet agents may be different in people with chronic kidney disease (CKD) for whom occlusive atherosclerotic events are less prevalent, and bleeding hazards might be increased. This is an update of a review first published in 2013.

OBJECTIVES

To evaluate the benefits and harms of antiplatelet agents in people with any form of CKD, including those with CKD not receiving renal replacement therapy, patients receiving any form of dialysis, and kidney transplant recipients.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Register of Studies up to 13 July 2021 through contact with the Information Specialist using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov.

SELECTION CRITERIA

We selected randomised controlled trials of any antiplatelet agents versus placebo or no treatment, or direct head-to-head antiplatelet agent studies in people with CKD. Studies were included if they enrolled participants with CKD, or included people in broader at-risk populations in which data for subgroups with CKD could be disaggregated.

DATA COLLECTION AND ANALYSIS

Four authors independently extracted data from primary study reports and any available supplementary information for study population, interventions, outcomes, and risks of bias. Risk ratios (RR) and 95% confidence intervals (CI) were calculated from numbers of events and numbers of participants at risk which were extracted from each included study. The reported RRs were extracted where crude event rates were not provided. Data were pooled using the random-effects model. Confidence in the evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach.

MAIN RESULTS

We included 113 studies, enrolling 51,959 participants; 90 studies (40,597 CKD participants) compared an antiplatelet agent with placebo or no treatment, and 29 studies (11,805 CKD participants) directly compared one antiplatelet agent with another. Fifty-six new studies were added to this 2021 update. Seven studies originally excluded from the 2013 review were included, although they had a follow-up lower than two months. Random sequence generation and allocation concealment were at low risk of bias in 16 and 22 studies, respectively. Sixty-four studies reported low-risk methods for blinding of participants and investigators; outcome assessment was blinded in 41 studies. Forty-one studies were at low risk of attrition bias, 50 studies were at low risk of selective reporting bias, and 57 studies were at low risk of other potential sources of bias. Compared to placebo or no treatment, antiplatelet agents probably reduces myocardial infarction (18 studies, 15,289 participants: RR 0.88, 95% CI 0.79 to 0.99, I² = 0%; moderate certainty). Antiplatelet agents has uncertain effects on fatal or nonfatal stroke (12 studies, 10.382 participants: RR 1.01, 95% CI 0.64 to 1.59, I² = 37%; very low certainty) and may have little or no effect on death from any cause (35 studies, 18,241 participants: RR 0.94, 95 % CI 0.84 to 1.06, I² = 14%; low certainty). Antiplatelet therapy probably increases major bleeding in people with CKD and those treated with haemodialysis (HD) (29 studies, 16,194 participants: RR 1.35, 95% CI 1.10 to 1.65, I² = 12%; moderate certainty). In addition, antiplatelet therapy may increase minor bleeding in people with CKD and those treated with HD (21 studies, 13,218 participants: RR 1.55, 95% CI 1.27 to 1.90, I² = 58%; low certainty). Antiplatelet treatment may reduce early dialysis vascular access thrombosis (8 studies, 1525 participants) RR 0.52, 95% CI 0.38 to 0.70; low certainty). Antiplatelet agents may reduce doubling of serum creatinine in CKD (3 studies, 217 participants: RR 0.39, 95% CI 0.17 to 0.86, I² = 8%; low certainty). The treatment effects of antiplatelet agents on stroke, cardiovascular death, kidney failure, kidney transplant graft loss, transplant rejection, creatinine clearance, proteinuria, dialysis access failure, loss of primary unassisted patency, failure to attain suitability for dialysis, need of intervention and cardiovascular hospitalisation were uncertain. Limited data were available for direct head-to-head comparisons of antiplatelet drugs, including prasugrel, ticagrelor, different doses of clopidogrel, abciximab, defibrotide, sarpogrelate and beraprost.

AUTHORS' CONCLUSIONS

Antiplatelet agents probably reduced myocardial infarction and increased major bleeding, but do not appear to reduce all-cause and cardiovascular death among people with CKD and those treated with dialysis. The treatment effects of antiplatelet agents compared with each other are uncertain.

Infarct on Brain Imaging, Subsequent Ischemic Stroke, and Clopidogrel-Aspirin Efficacy: A Post Hoc Analysis of a Randomized Clinical Trial

IMPORTANCE

In the Platelet-Oriented Inhibition in New TIA and Minor Ischemic Stroke (POINT) trial, acute treatment with clopidogrel-aspirin was associated with significantly reduced risk of recurrent stroke. There may be specific patient groups who are more likely to benefit from this treatment.

OBJECTIVE

To investigate whether the association of clopidogrel-aspirin with stroke recurrence in patients with minor stroke or high-risk transient ischemic attack (TIA) is modified by the presence of infarct on imaging attributed to the index event (index imaging) among patients enrolled in the POINT Trial.

DESIGN, SETTING, AND PARTICIPANTS

In the POINT randomized clinical trial, patients with high-risk TIA and minor ischemic stroke were enrolled at 269 sites in 10 countries in North America, Europe, Australia, and New Zealand from May 28, 2010, to December 19, 2017. In this post hoc analysis, patients were divided into 2 groups according to whether they had an acute infarct on index imaging. All POINT trial participants with information available on the presence or absence of acute infarct on index imaging were eligible for this study. Univariable Cox regression models evaluated associations between the presence of an infarct on index imaging and subsequent ischemic stroke and evaluated whether the presence of infarct on index imaging modified the association of clopidogrel-aspirin with subsequent ischemic stroke risk. Data were analyzed from July 2020 to May 2021.

EXPOSURES

Presence or absence of acute infarct on index imaging.

MAIN OUTCOMES AND MEASURES

The primary outcome is whether the presence of infarct on index imaging modified the association of clopidogrel-aspirin with subsequent ischemic stroke risk.

RESULTS

Of the 4881 patients enrolled in POINT, 4876 (99.9%) met the inclusion criteria (mean [SD] age, 65 [13] years; 2685 men [55.0%]). A total of 1793 patients (36.8%) had an acute infarct on index imaging. Infarct on index imaging was associated with ischemic stroke during follow-up (hazard ratio [HR], 3.68; 95% CI, 2.73-4.95; P < .001). Clopidogrel-aspirin vs aspirin alone was associated with decreased ischemic stroke risk in patients with an infarct on index imaging (HR, 0.56; 95% CI, 0.41-0.77; P < .001) compared with those without an infarct on index imaging (HR, 1.11; 95% CI, 0.74-1.65; P = .62), with a significant interaction association (P for interaction = .008).

CONCLUSIONS AND RELEVANCE

In this study, the presence of an acute infarct on index imaging was associated with increased risk of recurrent stroke and a more pronounced benefit from clopidogrel-aspirin. Future work should focus on validating these findings before targeting specific patient populations for acute clopidogrel-aspirin treatment.

Effect of Ginkgolide in Ischemic Stroke patients with large Artery Atherosclerosis: Results from a randomized trial

BACKGROUND

Dual antiplatelet therapy is considered beneficial in acute ischemic stroke (AIS) patients with intracranial artery stenosis (ICAS), with more bleeding events. Ginkgolide is shown to reduce platelet activation after infarction, which might be of benefit in AIS. We aimed to explore the effect of Ginkgolide in AIS patients with ICAS.

METHODS

This was a randomized, double-blinded, placebo-controlled trial conducted at 61 centers in China. Within 72 h after onset, consecutive patients diagnosed as AIS with ICAS were randomized to either Ginkgolide or placebo treatment. The primary outcome was the composite of mortality and recurrent stroke (ischemic or hemorrhagic) during first 4 weeks in an intention-to-treat analysis. Secondary functional outcome was assessed by modified Rankin Scale and improvement of stroke severity was assessed by National Institution of Health Stroke Scale at day 28. Safety outcome was measured by the rate of severe adverse event (SAE).

RESULTS

There were 936 patients randomized to either Ginkgolide or placebo treatment. Their average age was 64.2 ± 10.4 years old and 36.0% of the patients were female. The composite index event occurred in six patients in placebo group, and none occurred in Ginkgolide group (risk ratio 1.01; 95% CI 1.00-1.02). There were more patients who achieved favorable outcome in Ginkgolide group, compared with that of the placebo group (OR 2.16, 95%CI 1.37-3.41). SAE occurred in five (1.1%) patients in the Ginkgolide group and three (0.6%) in the placebo group (OR0.60, 95CI% 0.14-2.53). Intracranial hemorrhage occurred in 1/473 (0.2%) in the placebo group.

CONCLUSIONS

Ginkgolide, working as PAF antagonist, may reduce recurrent stroke in AIS with ICAS patients within 72 hours after onset. It might be an optional treatment in moderate-to-severe AIS patients with ICAS. (http://www.chictr.org.cn Number as ChiCTR-IPR-17012310).

Efficacy and Safety of Ticagrelor and Aspirin in Patients With Moderate Ischemic Stroke: An Exploratory Analysis of the THALES Randomized Clinical Trial

Question

Is dual antiplatelet therapy with ticagrelor plus aspirin of benefit for patients with moderate acute ischemic stroke (National Institutes of Health Stroke Scale [NIHSS] score of 4 to 5)?

Findings

In this exploratory post-hoc analysis of the THALES trial including 9983 patients with moderate or less severe stroke (NIHSS score of 0 to 3), treatment with ticagrelor plus aspirin showed similar efficacy and safety vs aspirin alone among patients presenting with moderate acute ischemic stroke and those presenting with less severe ischemic cerebrovascular events.

Meaning

Patients with moderate ischemic stroke may benefit from dual antiplatelet therapy with ticagrelor and aspirin.

Importance

Prior trials of dual antiplatelet therapy excluded patients with moderate ischemic stroke. These patients were included in the Acute Stroke or Transient Ischaemic Attack Treated With Ticagrelor and ASA for Prevention of Stroke and Death (THALES) trial, but results have not been reported separately, raising concerns about safety and efficacy in this subgroup.

Objective

To evaluate the efficacy and safety of ticagrelor plus aspirin in patients with moderate ischemic stroke (National Institutes of Health Stroke Scale [NIHSS] score of 4 to 5).

Design, Setting, and Participants

The THALES trial was a randomized trial conducted at 414 hospitals in 28 countries in January 2018 and December 2019. This exploratory analysis compared patients with moderate stroke (baseline NIHSS score of 4 to 5) with patients with less severe stroke (NIHSS score of 0 to 3). A total of 9983 patients with stroke were included in the present analysis, after excluding 2 patients with NIHSS scores greater than 5 and 1031 patients with transient ischemic attack. Data were analyzed from March to April 2021.

Interventions

Ticagrelor (180-mg loading dose on day 1 followed by 90 mg twice daily on days 2 to 30) or placebo within 24 hours after symptom onset. All patients received aspirin, 300 to 325 mg, on day 1 followed by aspirin, 75 to 100 mg, daily on days 2 to 30. Patients were observed for 30 additional days.

Main Outcomes and Measures

The primary outcome was time to stroke or death within 30 days. The primary safety outcome was time to severe bleeding.

Results

In total, 3312 patients presented with moderate stroke and 6671 presented with less severe stroke. Of those in the moderate stroke group, 1293 (39.0%) were female, and the mean (SD) age was 64.5 (10.8) years; of those in the less severe stroke group, 2518 (37.7%) were female, and the mean (SD) age was 64.8 (11.2) years. The observed primary outcome event rate in patients with moderate stroke was 7.6% (129 of 1671) for those in the ticagrelor group and 9.1% (150 of 1641) for those in the placebo group (hazard ratio, 0.84; 95% CI, 0.66-1.06); the primary outcome event rate in patients with less severe stroke was 4.7% (158 of 3359) for those in the ticagrelor group and 5.7% (190 of 3312) for those in the placebo group (hazard ratio, 0.82; 95% CI, 0.66-1.01) (P for interaction = .88). Severe bleeding occurred in 8 patients (0.5%) in the ticagrelor group and in 4 patients (0.2%) in the placebo group in those with moderate stroke compared with 16 patients (0.5%) and 3 patients (0.1%), respectively, with less severe stroke (P for interaction = .26).

Conclusions and Relevance

In this study, patients with a moderate ischemic stroke had consistent benefit from ticagrelor plus aspirin vs aspirin alone compared with patients with less severe ischemic stroke, with no further increase in the risk of intracranial bleeding or other severe bleeding events.

Trial Registration

ClinicalTrials.gov Identifier: NCT03354429

Benefits and Risks of Dual Versus Single Antiplatelet Therapy for Secondary Stroke Prevention: A Systematic Review for the 2021 Guideline for the Prevention of Stroke in Patients With Stroke and Transient Ischemic Attack

BACKGROUND

Dual antiplatelet therapy (DAPT) after ischemic stroke or transient ischemic attack may reduce recurrent stroke but also increase severe bleeding compared with single antiplatelet therapy (SAPT). The American Heart Association/American Stroke Association convened an evidence review committee to perform a systematic review and meta-analysis of the benefits and risks of DAPT compared with SAPT for secondary ischemic stroke prevention.

METHODS

The Medline, Embase, and Cochrane databases were searched on December 5, 2019, to identify phase III or IV randomized controlled trials (n≥100) from December 1999 to December 2019. We calculated unadjusted relative risks (RRs) and performed meta-analyses of studies based on the duration of treatment (short [≤90 days] versus long [>90 days]).

RESULTS

Three short-duration randomized controlled trials were identified that enrolled mostly patients with minor stroke or high risk transient ischemic attack. In these trials, DAPT, compared with SAPT, was associated with a lower 90-day risk of recurrent ischemic stroke (pooled RR, 0.68 [95% CI, 0.55-0.83], I ²=37.1%). There was no significant increase in major bleeding with DAPT in short-duration trials (pooled RR, 1.88 [95% CI, 0.93-3.83], I ²=8.9%). In 2 long-duration treatment randomized controlled trials (mean treatment duration, 18-40 months), DAPT was not associated with a significant reduction in recurrent ischemic stroke (pooled RR, 0.89 [95% CI, 0.79-1.02], I ²=1.4%), but was associated with a higher risk of major bleeding (pooled RR, 2.42 [95% CI, 1.37-4.30], I ²=75.5%).

CONCLUSIONS

DAPT was more effective than SAPT for prevention of secondary ischemic stroke when initiated early after the onset of minor stroke/high-risk transient ischemic attack and treatment duration was <90 days. However, when the treatment duration was longer and initiated later after stroke or transient ischemic attack onset, DAPT was not more effective than SAPT for ischemic stroke prevention and it increased the risk of bleeding.

F2R Polymorphisms and Clopidogrel Efficacy and Safety in Patients With Minor Stroke or TIA

OBJECTIVE

To investigate the association between protease-activated receptor-1 (PAR-1) gene F2R polymorphisms and efficacy of clopidogrel for minor stroke or TIA.

METHODS

Three single nucleotide polymorphisms (CYP2C19*2 [681G>A, rs4244285], CYP2C19*3 [636G>A, rs4986893], and F2R [IVSn-14 A/T, rs168753]) were genotyped among 2,924 patients randomized to clopidogrel plus aspirin (n = 1,461) or aspirin alone (n = 1,463). The primary efficacy outcome was new stroke (ischemic or hemorrhagic) and the safety outcome was any bleeding.

RESULTS

Overall, 859 (29.4%) were AA homozygotes, 1,479 (50.6%) were AT heterozygotes, and 586 (20.0%) were TT homozygotes for F2R IVSn-14 polymorphisms; 1,716 (58.7%) were carriers of at least 1 CYP2C19 loss-of-function allele (*2 or *3). Compared with aspirin alone, patients with clopidogrel-aspirin treatment had a low risk of new stroke in patients with AT genotype (7.6% vs 11.3%; hazard ratio [HR], 0.63; 95% confidence interval [CI], 0.44-0.89) and TT genotype (5.8% vs 11.6%; HR, 0.46; 95% CI, 0.25-0.82) but not in carriers of the AA genotype (10.8% vs 11.6%; HR, 0.95; 95% CI, 0.63-1.44) (p = 0.03 for interaction). The association between F2R IVSn-14 A/T polymorphism and clopidogrel response was present regardless of the carrier status of the CYP2C19 loss-of-function alleles. The F2R IVSn-14 genotypes were not associated with the risk of any bleeding for clopidogrel-aspirin treatment (p = 0.66 for interaction).

CONCLUSIONS

Among patients with minor ischemic stroke or TIA who were receiving clopidogrel and aspirin, those carrying the F2R IVSn-14 T allele had a lower rate of recurrent stroke than those who were not.

CLINICALTRIALSGOV IDENTIFIER

NCT00979589.

Comparison of outcome of patients with acute minor ischaemic stroke treated with intravenous t-PA, DAPT or aspirin

Background

Whether to treat minor stroke with intravenous tissue plasminogen activator (t-PA) treatment or antiplatelet therapy is a dilemma. Our study aimed to explore whether intravenous t-PA treatment, dual antiplatelet therapy (DAPT) and aspirin have different efficacies on outcomes in patients with minor stroke.

Methods

A post hoc analysis of patients with acute minor stroke treated with intravenous t-PA within 4.5 hours from a nationwide multicentric electronic medical record and patients with acute minor stroke treated with DAPT and aspirin from the Clopidogrel with Aspirin in Acute Minor Stroke or Transient Ischemic Attack Database. Minor stroke was defined by a score of 0–3 on the National Institutes of Health Stroke Scale at randomisation. Favourable functional outcome (defined as modified Rankin Scale (mRS) score of 0–1 or 0–2 at 3 months).

Results

Compared with those treated with intravenous t-PA, no significant association with 3-month favourable functional outcome (defined as mRS score of 0–1) was found neither in patients treated with aspirin (87.8% vs 89.4%; OR, 0.83; 95% CI, 0.46 to 1.50; p=0.53) nor those treated with DAPT (87.4% vs 89.4%; OR, 0.84; 95% CI, 0.46 to 1.52; p=0.56). Similar results were observed for the favourable functional outcome defined as mRS score of 0–2 at 3 months.

Conclusions

In our study, no significant advantage of intravenous t-PA over DAPT or aspirin was found. Due to insufficient sample size, our study is probably unable to draw such a conclusion that that intravenous t-PA was superior or non-superior to DAPT.

Comparison of long-term efficacy and safety between cilostazol and clopidogrel in chronic ischemic stroke: a nationwide cohort study

Background:

Previous clinical trials showed a significant difference in efficacy and safety among antiplatelets in acute ischemic stroke (IS). The present study wished to compare the efficacy and safety head-to-head between cilostazol and clopidogrel in chronic IS.

Methods:

This open prospective cohort study recruited chronic IS patients with an index hospitalization between 2001 and 2013 from Taiwan National Health Insurance Research Database. In the 504,191 hospitalized patients, patients who had missing information and history of atrial fibrillation or rheumatic heart disease, received mechanical valve replacement or anticoagulants, expired during the index hospitalization, received follow-up ⩽6 months, or had recurrent stroke within 6 months after index stroke were excluded.

Results:

Among the 15,968 eligible patients, 502 patients who consistently received either cilostazol or clopidogrel from the 7th month after the index stroke were included for analysis after propensity score matching. The 3-year primary outcomes showed similar frequency of recurrent IS, all-cause mortality, and acute myocardial infarction (AMI), and similar frequency of intracerebral hemorrhage, gastrointestinal bleeding, and major bleeding between the cilostazol and clopidogrel groups. Subgroup analysis revealed that patients with a history of hypertension or gastrointestinal bleeding had a trend of having lower frequency of recurrent IS or major bleeding, respectively, in the cilostazol group.

Conclusion:

The present real-world study demonstrated no significant difference in efficacy and safety between cilostazol and clopidogrel in chronic IS. However, cilostazol might be better than clopidogrel in patients with a history of hypertension or gastrointestinal bleeding.

Aspirin plus clopidogrel versus aspirin mono-therapy for ischemic stroke: a meta-analysis

Objectives. Stroke is a common condition after a transient ischemic attack (TIA) or minor ischemic stroke (IS). Adding clopidogrel to aspirin may yield more beneficial outcomes than aspirin mono-therapy; meanwhile, the risk of bleeding in the acute phase remains poorly understood. Therefore, there is increasing emphasis on the risks and benefits of clopidogrel with aspirin compared with aspirin mono-therapy in an effort to treat TIA/IS. Design. We searched several electronic databases, including PubMed, Cochrane, and Embase, to identify eligible randomized controlled trials (RCTs) based on the index words comparing dual-antiplatelet therapy to aspirin mono-therapy for secondary stroke prevention updated to December, 2018. Results. A total of 11 RCTs met our inclusion criteria. The pooled analysis showed that clopidogrel plus aspirin was associated with a trend toward a reduction in recurrent IS (RR = 0.72, 95%CI = 0.65-0.81, p < .001), but not the recurrent stroke rate (RR = 0.81, 95% CI = 0.63-1.03, p = .09) than aspirin mono-therapy. There were differences in bleeding episodes (RR = 1.81, 95%CI = 1.65-1.99, p < .001), moderate-severe major bleeding (RR = 1.64, 95% CI = 1.24-2.16, p = .0005), or mild bleeding (RR = 2.25, 95%CI = 1.54-3.31, p < .001) between the study groups. Meanwhile, no benefit of reducing the risk of intracranial hemorrhage with dual-antiplatelet therapy was found in TIA/IS patients (RR = 1.44, 95% CI = 0.95-2.19, p = .09). Conclusions. The addition of clopidogrel to aspirin for patients with TIA or IS appeared to significantly reduce the risk of IS recurrence with a possible increase in the risk of bleeding compared with aspirin alone.

Ticagrelor plus aspirin versus clopidogrel plus aspirin for platelet reactivity in patients with minor stroke or transient ischaemic attack: open label, blinded endpoint, randomised controlled phase II trial

OBJECTIVE

To test the hypothesis that ticagrelor plus aspirin is safe and superior to clopidogrel plus aspirin for reducing high platelet reactivity at 90 days and stroke recurrence in patients with minor stroke or transient ischaemic attack, particularly in carriers of the CYP2C19 loss-of-function allele and patients with large artery atherosclerosis.

DESIGN

Open label, blinded endpoint, randomised controlled phase II trial.

SETTING

Prospective studies conducted at 26 centres in China, August 2015 to March 2017.

PARTICIPANTS

675 patients with acute minor stroke or transient ischaemic attack.

INTERVENTION

Ticagrelor (180 mg loading dose, 90 mg twice daily thereafter) or clopidogrel (300 mg loading dose, 75 mg daily thereafter) on a background of aspirin (100 mg daily for the first 21 days) within 24 hours of symptom onset.

MAIN OUTCOME MEASURES

Primary outcome was the proportion of patients with high platelet reactivity at 90 days. High platelet reactivity was defined as P2Y12 reaction units of more than 208. Secondary outcomes included high platelet reactivity at 90 days (7 days either way) in patients carrying genetic variants that would affect clopidogrel metabolism, and any stroke (ischaemic or haemorrhagic) recurrence at 90 days (7 days either way), six months, and one year.

RESULTS

At 90 days, high platelet reactivity occurred in 35 (12.5%) of 280 patients in the ticagrelor/aspirin group and 86 (29.7%) of 290 patients in the clopidogrel/aspirin group (risk ratio 0.40; 95% confidence interval 0.28 to 0.56; P<0.001), and in 10.8% versus 35.4% (0.31; 0.18 to 0.49; P<0.001) of patients carrying CYP2C19 loss-of-function alleles. Stroke occurred in 21 (6.3%) of 336 patients in the ticagrelor/aspirin group and 30 (8.8%) of 339 patients in the clopidogrel/aspirin group (hazard ratio 0.70; 95% confidence interval 0.40 to 1.22; P=0.20). Patients with large artery atherosclerosis in the ticagrelor/aspirin group had a lower stroke recurrence at 90 days than those in the clopidogrel/aspirin group (6.0% v 13.1%; hazard ratio 0.45, 95% confidence interval 0.20 to 0.98; P=0.04). No difference was seen in the rates of major or minor haemorrhagic events between the ticagrelor/aspirin and clopidogrel/aspirin groups (4.8% v 3.5%; P=0.42).

CONCLUSION

Patients with minor stroke or transient ischaemic attack who are treated with ticagrelor plus aspirin have a lower proportion of high platelet reactivity than those who are treated with clopidogrel plus aspirin, particularly for those who are carriers of the CYP2C19 loss-of-function allele. The results of this study should be evaluated further in large scale, phase III trials and in different populations.

TRIAL REGISTRATION

Clinicaltrials.gov NCT02506140.

Clopidogrel plus aspirin versus aspirin alone for acute minor ischaemic stroke or high risk transient ischaemic attack: systematic review and meta-analysis

OBJECTIVE

To assess the effectiveness and safety of dual agent antiplatelet therapy combining clopidogrel and aspirin to prevent recurrent thrombotic and bleeding events compared with aspirin alone in patients with acute minor ischaemic stroke or transient ischaemic attack (TIA).

DESIGN

Systematic review and meta-analysis of randomised, placebo controlled trials.

DATA SOURCES

Medline, Embase, Cochrane Central Register of Controlled Trials, Cochrane Library, ClinicalTrials.gov, WHO website, PsycINFO, and grey literature up to 4 July 2018.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES AND METHODS

Two reviewers independently screened potentially eligible studies according to predefined selection criteria and assessed the risk of bias using a modified version of the Cochrane risk of bias tool. A third team member reviewed all final decisions, and the team resolved disagreements through discussion. When reports omitted data that were considered important, clarification and additional information was sought from the authors. The analysis was conducted in RevMan 5.3 and MAGICapp based on GRADE methodology.

RESULTS

Three eligible trials involving 10 447 participants were identified. Compared with aspirin alone, dual antiplatelet therapy with clopidogrel and aspirin that was started within 24 hours of symptom onset reduced the risk of non-fatal recurrent stroke (relative risk 0.70, 95% confidence interval 0.61 to 0.80, I²=0%, absolute risk reduction 1.9%, high quality evidence), without apparent impact on all cause mortality (1.27, 0.73 to 2.23, I²=0%, moderate quality evidence) but with a likely increase in moderate or severe extracranial bleeding (1.71, 0.92 to 3.20, I²=32%, absolute risk increase 0.2%, moderate quality evidence). Most stroke events, and the separation in incidence curves between dual and single therapy arms, occurred within 10 days of randomisation; any benefit after 21 days is extremely unlikely.

CONCLUSIONS

Dual antiplatelet therapy with clopidogrel and aspirin given within 24 hours after high risk TIA or minor ischaemic stroke reduces subsequent stroke by about 20 in 1000 population, with a possible increase in moderate to severe bleeding of 2 per 1000 population. Discontinuation of dual antiplatelet therapy within 21 days, and possibly as early as 10 days, of initiation is likely to maximise benefit and minimise harms.

Risks and benefits of clopidogrel–aspirin in minor stroke or TIA

Objective:

To investigate the short-term time course risks and benefits of clopidogrel with aspirin in minor ischemic stroke or TIA.

Methods:

Data were derived from the Clopidogrel in High-Risk Patients with Acute Nondisabling Cerebrovascular Events (CHANCE) trial. The primary outcome was a new ischemic stroke. Safety outcomes included any bleeding and moderate to severe bleeding. Time course analyses were performed for the outcomes of both stroke and bleeding.

Results:

A total of 145 (71.1%), 13 (6.4%), and 12 (5.9%) of 204 new ischemic strokes in the clopidogrel–aspirin group vs 223 (75.6%), 19 (6.4%), and 8 (2.7%) of 295 in the aspirin alone group occurred at the first, second, and third week, respectively. A total of 23 (38.3%), 15 (25.0%), and 9 (15.0%) of 60 bleeding cases in the clopidogrel–aspirin group vs 15 (36.6%), 8 (19.5%), and 3 (7.3%) of 41 in the aspirin alone group occurred at the first, second, and third week, respectively. Clopidogrel–aspirin treatment numerically reduced the risk of ischemic stroke within the first 2 weeks. From the 10th day, the number of any bleeding cases caused by dual antiplatelets outweighed that of new stroke reduced by dual antiplatelets.

Conclusions:

Clopidogrel–aspirin treatment may have a benefit of reducing stroke risk outweighing the potential risk of increased bleeding especially within the first 2 weeks compared with aspirin alone in patients with minor stroke or TIA.

Clinicaltrials.gov identifier:

NCT00979589.

Classification of evidence:

This study provides Class II evidence that for patients with minor stroke or TIA, the reduction of stroke risk from clopidogrel plus aspirin within the first 2 weeks outweighs the risk of bleeding compared with aspirin alone.

Ticagrelor in Acute Stroke or Transient Ischemic Attack in Asian Patients: From the SOCRATES Trial (Acute Stroke or Transient Ischemic Attack Treated With Aspirin or Ticagrelor and Patient Outcomes)

BACKGROUND AND PURPOSE

In the SOCRATES trial (Acute Stroke or Transient Ischemic Attack Treated With Aspirin or Ticagrelor and Patient Outcomes), ticagrelor was not superior to aspirin. Because of differences in patient demographics and stroke disease pattern in Asia, outcomes of ticagrelor versus aspirin were assessed among Asian patients in a prespecified exploratory analysis.

METHODS

Baseline demographics, treatment effects, and safety of ticagrelor and aspirin were assessed among Asian patients. Differences in outcomes between groups were assessed using Cox proportional hazard model.

RESULTS

A total of 3858 (29.2%) SOCRATES participants were recruited in Asia. Among the Asian patients, the primary end point event occurred in 186 (9.6%) of the 1933 patients treated with ticagrelor, versus 224 (11.6%) of the 1925 patients treated with aspirin (hazard ratio, 0.81; 95% confidence interval, 0.67-0.99). The exploratory P value for treatment-by-region interaction was 0.27. The primary end point event rate in the Asian subgroup was numerically higher than that in the non-Asian group (10.6% versus 5.7%; nominal P<0.01). Among the Asian patients, the rate of PLATO (Platelet Inhibition and Patient Outcomes)-defined major bleeding was similar in the ticagrelor group and the aspirin group (0.6% versus 0.8%; hazard ratio, 0.76; 95% confidence interval, 0.36-1.61).

CONCLUSIONS

The event rates were numerically higher in the Asian patients. Among the Asian patients with acute stroke or transient ischemic attacks, there was a trend toward a lower hazard ratio in reducing risk of the primary end point of stroke, myocardial infarction, or death in the ticagrelor group.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT01994720.

Effect of Estimated Glomerular Filtration Rate Decline on the Efficacy and Safety of Clopidogrel With Aspirin in Minor Stroke or Transient Ischemic Attack

Background and Purpose—

Patients with chronic kidney disease (CKD) are at a particularly high risk for ischemic and bleeding events. Limited data exist as to the efficacy and safety of clopidogrel in stroke patients with renal dysfunction. Therefore, we sought to assess the impact of decreased kidney function on clinical outcomes for stroke patients on clopidogrel–aspirin treatment.

Methods—

Patients in the CHANCE trial (Clopidogrel in High-Risk Patients With Acute Nondisabling Cerebrovascular Events) were randomized to clopidogrel–aspirin or aspirin-alone treatment. The primary efficacy outcome was new stroke during 90 days, whereas bleeding was the safety outcome. Patients were stratified according to estimated glomerular filtration rate.

Results—

Dual clopidogrel–aspirin therapy was associated with a marked reduction in new strokes compared with the therapy of aspirin alone in patients with normal renal function (hazard ratio, 0.77; 95% confidence interval, 0.60–0.98; P =0.02) and mild CKD (hazard ratio, 0.60; 95% confidence interval, 0.45–0.79; P <0.01), whereas in patients with moderate CKD, no significant benefit from clopidogrel therapy was detected (hazard ratio, 1.00; 95% confidence interval, 0.43–2.35; P =0.99). There was no clear difference in bleeding episodes by treatment assignment across categories of renal impairment.

Conclusions—

Clopidogrel plus aspirin could decrease new stroke in patients with normal kidney function and mild CKD, but no extra benefit was observed in those with moderate CKD. Bleeding risk from the dual therapy did not seem to increase in mild or moderate CKD patients.

Clinical Trial Registration—

URL: http://www.clinicaltrials.gov . Unique identifier: NCT00979589.