Cilostazol in Acute Ischemic Stroke Treatment (CAIST Trial): a randomized double-blind non-inferiority trial

Effects of dual antiplatelet therapy (DAPT) compared to single antiplatelet therapy (SAPT) in patients with traumatic brain injury

Japan is one of the world's most aging societies and the number of elderly patients taking antithrombotic drugs is increasing. In recent years, dual antiplatelet therapy (DAPT), in which two antiplatelet drugs are administered, has become common in anticipation of its high therapeutic efficacy. However, there are concerns about increased bleeding complications in use of DAPT. Therefore, the goal of this study was to investigate the effects of DAPT in patients with traumatic brain injury (TBI). A prospective, multicenter, observational study was conducted from December 2019 to May 2021 to examine the effects of antithrombotic drugs and reversal drugs in 721 elderly patients with TBI. In the current study, the effect of DAPT on TBI was examined in a secondary analysis. Among the registered patients, 132 patients taking antiplatelet drugs only were divided into those treated with single antiplatelet therapy (SAPT) (n=106) and those treated with DAPT (n=26) prior to TBI. Glasgow Coma Scale (GCS) on admission, pupillary findings, course during hospitalization, and outcome were compared in the two groups. A similar analysis was performed in patients with a mild GCS of 13-15 (n=95) and a moderate to severe GCS of 3-12 (n=37) on admission. The DAPT group had significantly more males (67.0 % vs. 96.2 %), a higher severity of illness on admission, and a higher frequency of brain herniation findings on head CT (21.7 % vs. 46.2 %), resulting in significantly higher mortality (12.3 % vs. 30.8 %). The only significant factor for mortality was severity on admission. The rate of DAPT was significantly higher in patients with a moderate to severe GCS on admission, and DAPT was the only significant factor related to severity on admission. These findings suggest that the severity of injury on admission influences the outcome six months after injury, and that patients with more severe TBI on admission are more likely to have been treated with DAPT compared to SAPT.

European stroke organisation (ESO) guideline on cerebral small vessel disease, part 2, lacunar ischaemic stroke

A quarter of ischaemic strokes are lacunar subtype, typically neurologically mild, usually resulting from intrinsic cerebral small vessel pathology, with risk factor profiles and outcome rates differing from other stroke subtypes. This European Stroke Organisation (ESO) guideline provides evidence-based recommendations to assist with clinical decisions about management of lacunar ischaemic stroke to prevent adverse clinical outcomes. The guideline was developed according to ESO standard operating procedures and Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) methodology. We addressed acute treatment (including progressive lacunar stroke) and secondary prevention in lacunar ischaemic stroke, and prioritised the interventions of thrombolysis, antiplatelet drugs, blood pressure lowering, lipid lowering, lifestyle, and other interventions and their potential effects on the clinical outcomes recurrent stroke, dependency, major adverse cardiovascular events, death, cognitive decline, mobility, gait, or mood disorders. We systematically reviewed the literature, assessed the evidence and where feasible formulated evidence-based recommendations, and expert concensus statements. We found little direct evidence, mostly of low quality. We recommend that patients with suspected acute lacunar ischaemic stroke receive intravenous alteplase, antiplatelet drugs and avoid blood pressure lowering according to current acute ischaemic stroke guidelines. For secondary prevention, we recommend single antiplatelet treatment long-term, blood pressure control, and lipid lowering according to current guidelines. We recommend smoking cessation, regular exercise, other healthy lifestyle modifications, and avoid obesity for general health benefits. We cannot make any recommendation concerning progressive stroke or other drugs. Large randomised controlled trials with clinically important endpoints, including cognitive endpoints, are a priority for lacunar ischaemic stroke.

The Role of Cilostazol, a Phosphodiesterase-3 Inhibitor, in the Development of Atherosclerosis and Vascular Biology: A Review with Meta-Analysis

Atherosclerotic cardiovascular disease (ASCVD) stands as the leading global cause of mortality. Addressing this vital and pervasive condition requires a multifaceted approach, in which antiplatelet intervention plays a pivotal role, together with antihypertensive, antidiabetic, and lipid-lowering therapies. Among the antiplatelet agents available currently, cilostazol, a phosphodiesterase-3 inhibitor, offers a spectrum of pharmacological effects. These encompass vasodilation, the impediment of platelet activation and aggregation, thrombosis inhibition, limb blood flow augmentation, lipid profile enhancement through triglyceride reduction and high-density lipoprotein cholesterol elevation, and the suppression of vascular smooth muscle cell proliferation. However, the role of cilostazol has not been clearly documented in many guidelines for ASCVD. We comprehensively reviewed the cardiovascular effects of cilostazol within randomized clinical trials that compared it to control or active agents and involved individuals with previous coronary artery disease or stroke, as well as those with no previous history of such conditions. Our approach demonstrated that the administration of cilostazol effectively reduced adverse cardiovascular events, although there was less evidence regarding its impact on myocardial infarction. Most studies have consistently reported its favorable effects in reducing intermittent claudication and enhancing ambulatory capacity in patients with peripheral arterial disease. Furthermore, cilostazol has shown promise in mitigating restenosis following coronary stent implantation in patients with acute coronary syndrome. While research from more diverse regions is still needed, our findings shed light on the broader implications of cilostazol in the context of atherosclerosis and vascular biology, particularly for individuals at high risk of ASCVD.

Pharmacological Strategies for Stroke Intervention: Assessment of Pathophysiological Relevance and Clinical Trials

OBJECTIVES

The present review describes stroke pathophysiology in brief and discusses the spectrum of available treatments with different promising interventions that are in clinical settings or are in clinical trials.

METHODS

Relevant articles were searched using Google Scholar, Cochrane Library, and PubMed. Keywords for the search included ischemic stroke, mechanisms, stroke interventions, clinical trials, and stem cell therapy.

RESULTS AND CONCLUSION

Stroke accounts to a high burden of mortality and morbidity around the globe. Time is an important factor in treating stroke. Treatment options are limited; however, agents with considerable efficacy and tolerability are being continuously explored. With the advances in stroke interventions, new therapies are being formulated with a hope that these may aid the ongoing protective and reparative processes. Such therapies may have an extended therapeutic time window in hours, days, weeks, or longer and may have the advantage to be accessible by a majority of the patients.

Antithrombotic therapy for secondary prevention in patients with stroke or transient ischemic attack: A multiple treatment network meta-analysis of randomized controlled trials

Objective

As stroke represents one of the leading causes of mortality and disability worldwide, we aimed to determine the preventive effect of different antiplatelet therapies after an ischemic stroke or transient ischemic attack.

Methods

Network meta-analysis evaluating antiplatelet regimes after an ischemic stroke or transient ischemic attack. Searches were conducted in MEDLINE, EMBASE, and Cochrane Library databases until Nov. 23, 2021, for randomized controlled trials. Direct comparisons within trials were combined with indirect evidence from other trials by using a frequentist model. An additive network meta-analysis model was used to evaluate the influence of individual components. The primary efficacy endpoint was a recurrent stroke, the main safety outcomes were the risk of major bleeding and mortality at the longest available follow-up.

Results

58 randomized controlled trials (175,730 patients) were analyzed. The analysis involved 20 antithrombotic strategies including different antiplatelet agents, combinations with aspirin, and anticoagulant therapies. Cilostazol proved to be the most efficacious in reducing stroke recurrence and the risk of bleeding (RR = 0.66, 95%CI = 0.55–0.80 and RR = 0.39, 95%CI = 0.08–2.01) compared to aspirin, respectively. Intensification with combinations of aspirin with ticagrelor or clopidogrel resulted in a lower risk of stroke recurrence (RR = 0.79, 95%CI = 0.67–0.93 and RR = 0.79, 95%CI = 0.72–0.87) but carried a higher bleeding risk (RR = 3.01, 95%CI = 1.65–5.49 and RR = 1.78 95%CI = 1.49–2.13).

Conclusion

The prognosis of patients with an ischemic stroke or transient ischemic attack is improved with antiplatelets. Cilostazol showed the best risk-benefit characteristics without trade-off with the risk of major bleeding. Improved stroke recurrence with intensified antiplatelet regimens is counterbalanced with higher bleeding risk, and consequently, mortality remains unaffected. Treatment decisions in stroke survivals should integrate the assessment of bleeding risk for better identification of patients with the highest benefit of treatment intensification.

Systematic review registration

Prospero registration number: CRD42020197143, https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=197143.

The Efficacy and Safety of Cilostazol vs. Aspirin for Secondary Stroke Prevention: A Systematic Review and Meta-Analysis

Background

Cilostazol is often used in Asia-Pacific countries for stroke prevention. The current systematic review and meta-analysis aimed to evaluate the effectiveness, safety, and adverse outcomes of cilostazol monotherapy compared to aspirin monotherapy for secondary stroke prevention.

Methods

The researchers conducted a comprehensive research in multiple databases (PubMed, Embase, and Cochrane library) of randomized controlled trials from conception to December 2020. The primary efficacy outcome was the occurrence of any stroke, the primary safety outcome was the bleeding risk, and the primary adverse outcome was the rate of headache and dizziness. The Mantel-Haenszel method was used to calculate a random-effects prediction. Cilostazol and aspirin were compared using a pooled risk assessment with 95% CIs.

Results

Six studies involving 5,617 patients were included in this review. Compared with aspirin monotherapy, cilostazol was associated with significantly lower rates of any strokes (RR: 0.67; 95% CI: 0.55–0.82) and significantly lower bleeding rates [risk ratio (RR): 0.53; 95% CI: 0.37–0.74]. However, compared with aspirin monotherapy, cilostazol was associated with significantly higher rates of headache (RR: 1.77; 95% CI: 1.41–2.20) and dizziness (RR: 1.28; 95% CI: 1.08–1.52).

Conclusions

Consistent with previous studies, cilostazol monotherapy is superior to aspirin monotherapy in reducing the rate of any strokes and the bleeding risk after having a stroke. However, the use of cilostazol monotherapy is associated with several adverse life outcomes such as headaches and dizziness.

2022 Update of the Korean Clinical Practice Guidelines for Stroke: Antithrombotic Therapy for Patients with Acute Ischemic Stroke or Transient Ischemic Attack

Antithrombotic therapy is a cornerstone of acute ischemic stroke (AIS) management and secondary stroke prevention. Since the first version of the Korean Clinical Practice Guideline (CPG) for stroke was issued in 2009, significant progress has been made in antithrombotic therapy for patients with AIS, including dual antiplatelet therapy in acute minor ischemic stroke or high-risk transient ischemic stroke and early oral anticoagulation in AIS with atrial fibrillation. The evidence is widely accepted by stroke experts and has changed clinical practice. Accordingly, the CPG Committee of the Korean Stroke Society (KSS) decided to update the Korean Stroke CPG for antithrombotic therapy for AIS. The writing members of the CPG committee of the KSS reviewed recent evidence, including clinical trials and relevant literature, and revised recommendations. A total of 35 experts were invited from the KSS to reach a consensus on the revised recommendations. The current guideline update aims to assist healthcare providers in making well-informed decisions and improving the quality of acute stroke care. However, the ultimate treatment decision should be made using a holistic approach, considering the specific medical conditions of individual patients.

Association of Timing for Starting Dual Antiplatelet Treatment With Cilostazol and Recurrent Stroke: A CSPS.com Trial Post Hoc Analysis

Background and Objectives

Long-term treatment with the combination of cilostazol with aspirin or clopidogrel showed a lower risk of stroke recurrence compared to aspirin or clopidogrel alone after high-risk noncardioembolic ischemic stroke in a randomized trial. We aimed to determine whether the effect of the dual medication compared to monotherapy on risk of recurrent ischemic stroke differs according to timing of starting medication after stroke onset.

Methods

In a subanalysis of the randomized controlled trial, patients between 8 and 180 days after stroke onset were randomly assigned to receive aspirin or clopidogrel alone or a combination of cilostazol with aspirin or clopidogrel. They were divided into 3 groups according to the timing of starting trial treatment: between 8 and 14 days after stroke onset (8–14 days group), between 15 and 28 days after stroke onset (15–28 days group), and between 29 and 180 days after stroke onset (29–180 days group). The primary efficacy outcome was the first recurrence of ischemic stroke. Safety outcomes included severe or life-threatening bleeding.

Results

Of 1,879 patients, 498 belonged to the 8–14 days group, 467 to the 15–28 days group, and 914 to the 29–180 days group. There was a significant treatment-by-subgroup interaction for the recurrence of ischemic stroke between trial treatment and trichotomized groups. The recurrence of ischemic stroke was less common with dual therapy than with monotherapy in the 15–28 days group (annualized rate 1.5% vs 4.9%, respectively; adjusted hazard ratio 0.34 [95% CI 0.12–0.95]) and the 29–180 days group (1.9% vs 4.4%, respectively; 0.27 [0.12–0.63]) and similarly common in the 8–14 days group (4.5% for both; 1.02 [0.51–2.04]). Severe or life-threatening bleeding occurred similarly between patients on dual therapy and those on monotherapy in any of the trichotomized groups (crude hazard ratio 0.22 [95% CI 0.03–1.88] in the 8–14 days group, 1.07 [0.15–7.60] in the 15–28 days group, and 0.76 [0.24–2.39] in the 29–180 days group).

Discussion

Long-term dual antiplatelet therapy using cilostazol starting 15–180 days after stroke onset, compared to therapy started 8–14 days after onset, was more effective for secondary stroke prevention than monotherapy without increasing hemorrhage risk.

Trial Registration Information

ClinicalTrials.gov NCT01995370; UMIN Clinical Trials Registry 000012180.

Classification of Evidence

This study provides Class II evidence that for patients with acute noncardioembolic stroke taking either aspirin or clopidogrel, the addition of cilostazol 15–180 days after stroke onset decreases the risk of recurrent ischemic stroke.

Oral antiplatelet therapy for acute ischaemic stroke

BACKGROUND

In people with acute ischaemic stroke, platelets become activated and can cause blood clots to form and block an artery in the brain, resulting in damage to part of the brain. Such damage gives rise to the symptoms of stroke. Antiplatelet therapy might reduce the volume of brain damaged by ischaemia and also reduce the risk of early recurrent ischaemic stroke, thereby reducing the risk of early death and improving long-term outcomes in survivors. However, antiplatelet therapy might also increase the risk of fatal or disabling intracranial haemorrhage.

OBJECTIVES

To assess the efficacy and safety of immediate oral antiplatelet therapy (i.e. started as soon as possible and no later than two weeks after stroke onset) in people with acute presumed ischaemic stroke.

SEARCH METHODS

We searched the Cochrane Stroke Group Trials Register, CENTRAL, MEDLINE Ovid, Embase Ovid, and two trials registers, and performed forward reference/cited reference searching in August 2020.

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing oral antiplatelet therapy (started within 14 days of the stroke) with control in people with definite or presumed ischaemic stroke.

DATA COLLECTION AND ANALYSIS

Two review authors independently applied the inclusion criteria and assessed trial quality. For the included trials, they extracted and cross-checked the data. They assessed risk of bias of each study using the Risk of Bias 1 (RoB1) tool and overall certainty of the evidence for each outcome using the GRADE approach.

MAIN RESULTS

We included 11 studies involving 42,226 participants. Three new trials have been added since the last update (743 participants). As per the previous version of this review, two trials testing aspirin 160 mg to 300 mg once daily, started within 48 hours of onset, contributed 96% of the data. The risk of bias was low. The maximum follow-up was six months. With treatment, there was a decrease in death or dependency at the end of follow-up (odds ratio (OR) 0.95, 95% confidence interval (CI) 0.91 to 0.99; 7 RCTs, 42,034 participants; moderate-certainty evidence). For every 1000 people treated with aspirin, 13 people would avoid death or dependency (number needed to treat for an additional beneficial outcome 79).

AUTHORS' CONCLUSIONS

Antiplatelet therapy with aspirin 160 mg to 300 mg daily, given orally (or by nasogastric tube or per rectum in people who cannot swallow) and started within 48 hours of onset of presumed ischaemic stroke, significantly decreased death and dependency, and reduced the risk of early recurrent ischaemic stroke without a major risk of early haemorrhagic complications; long-term outcomes were improved.

Update on Cilostazol: A Critical Review of Its Antithrombotic and Cardiovascular Actions and Its Clinical Applications

Cilostazol, a phosphodiesterase III inhibitor, has vasodilating and antiplatelet properties with a low rate of bleeding complications. It has been used over the past 25 years for improving intermittent claudication in patients with peripheral artery disease (PAD). Cilostazol also has demonstrated efficacy in patients undergoing percutaneous revascularization procedures for both PAD and coronary artery disease. In addition to its antithrombotic and vasodilating actions, cilostazol also inhibits vascular smooth muscle cell proliferation via phosphodiesterase III inhibition, thus mitigating restenosis. Accumulated evidence has shown that cilostazol, due to its "pleiotropic" effects, is a useful, albeit underutilized, agent for both coronary artery disease and PAD. It is also potentially useful after ischemic stroke and is an alternative in those who are allergic or intolerant to classical antithrombotic agents (eg, aspirin or clopidogrel). These issues are herein reviewed together with the pharmacology and pharmacodynamics of cilostazol. Large studies and meta-analyses are presented and evaluated. Current guidelines are also discussed, and the spectrum of cilostazol's actions and therapeutic applications are illustrated.

Antiplatelet regimens for Asian patients with ischemic stroke or transient ischemic attack: a systematic review and network meta-analysis

Background

The optimal antiplatelet treatment for the secondary prevention of non-cardioembolic stroke or transient ischemic attack (TIA) remains uncertain in Asians.

Methods

We searched for eligible randomized control trials in Medline, Embase, and the Cochrane Library. A Bayesian network meta-analysis (NMA) was performed to assess the efficacy and safety of antiplatelet regimens with placebo as the control. Each therapy was compared using relative risk ratios (RR) and 95% credible intervals (CrI), and ranked according to the value of the surface under the cumulative ranking curve.

Results

A total of 84,103 patients from 32 studies were included: patients in used aspirin (n=26,834); cilostazol (n=3,303); clopidogrel (n=12,406); prasugrel (n=1,885); sarpogrelate (n=752); ticagrelor (n=1,933); ticlopidine (n=1,644); triflusal (n=391); aspirin plus cilostazol (n=1,120), aspirin plus clopidogrel (n=4,623); aspirin plus dipyridamole (n=10,853); aspirin plus ticagrelor (n=5,859); aspirin plus ticlopidine (n=132). Patients who used aspirin plus clopidogrel and cilostazol had a lower risk of recurrent stroke than those who used placebo. Patients administered with aspirin plus ticagrelor, aspirin plus clopidogrel, and cilostazol had a lower risk of composite vascular events than those administered placebo. Patients administered aspirin plus ticagrelor had a higher risk of major bleeding than those administered placebo. Clustered three-dimensional rank plots of recurrent stroke, major bleeding, and composite vascular events demonstrated that cilostazol had higher values of the surface under the cumulative ranking curve than other treatments.

Conclusions

Of the antiplatelet regimens, cilostazol showed the best net clinical benefits than other antiplatelet regimens in Asians with non-cardioembolic stroke or TIA.

Cilostazol for secondary stroke prevention: systematic review and meta-analysis

Background

Stroke is one of the leading causes of death worldwide. Cilostazol, an antiplatelet and phosphodiesterase 3 inhibitor, has not been clearly established for ischaemic stroke use. We aim to determine the efficacy and safety of cilostazol for secondary stroke prevention.

Methods

MEDLINE, EMBASE, Cochrane Library, Web of Science and ClinicalTrials.gov were searched from inception to 25 September 2020, for randomised trials comparing the efficacy and safety of cilostazol monotherapy or dual therapy with another antiplatelet regimen or placebo, in patients with ischaemic stroke. Version 2 of the Cochrane risk-of-bias tool for randomised trials (RoB 2) was used to assess study quality. This meta-analysis was reported in line with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement.

Results

Eighteen randomised trials comprising 11 429 participants were included in this meta-analysis. Most trials possessed low risk of bias and were of low heterogeneity. Cilostazol significantly reduced the rate of ischaemic stroke recurrence (risk ratio, RR=0.69, 95% CI 0.58 to 0.81), any stroke recurrence (RR=0.64, 95% CI 0.54 to 0.74) and major adverse cardiovascular events (RR=0.67, 95% CI 0.56 to 0.81). Cilostazol did not significantly decrease mortality (RR=0.90, 95% CI 0.64 to 1.25) or increase the rate of good functional outcome (Modified Rankin Scale score of 0–1; RR=1.07, 95% CI 0.95 to 1.19). Cilostazol demonstrated favourable safety profile, significantly reducing the risk of intracranial haemorrhage (RR=0.46, 95% CI 0.31 to 0.68) and major haemorrhagic events (RR=0.49, 95% CI 0.34 to 0.70).

Conclusions

Cilostazol demonstrated superior efficacy and safety profiles compared with traditional antiplatelet regimens such as aspirin and clopidogrel for secondary stroke prevention but does not appear to affect functional outcomes. Future randomised trials can be conducted outside East Asia, or compare cilostazol with a wider range of antiplatelet agents.

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.

Cilostazol for Secondary Prevention of Stroke and Cognitive Decline: Systematic Review and Meta-Analysis

BACKGROUND AND PURPOSE

Cilostazol, a phosphodiesterase 3' inhibitor, is used in Asia-Pacific countries for stroke prevention, but rarely used elsewhere. In addition to weak antiplatelet effects, it stabilizes endothelium, aids myelin repair and astrocyte-neuron energy transfer in laboratory models, effects that may be beneficial in preventing small vessel disease progression.

METHODS

A systematic review and meta-analysis of unconfounded randomized controlled trials of cilostazol to prevent stroke, cognitive decline, or radiological small vessel disease lesion progression. Two reviewers searched for papers (January 1, 2019 to July 16, 2019) and extracted data. We calculated Peto odds ratios (ORs) and 95% CIs for recurrent ischemic, hemorrhagic stroke, death, adverse symptoms, with sensitivity analyses. The review is registered (CRD42018084742).

RESULTS

We included 20 randomized controlled trials (n=10 505), 18 in ischemic stroke (total n=10 449) and 2 in cognitive impairment (n=56); most were performed in Asia-Pacific countries. Cilostazol decreased recurrent ischemic stroke (17 trials, n=10 225, OR=0.68 [95% CI, 0.57-0.81]; P<0.0001), hemorrhagic stroke (16 trials, n=9736, OR=0.43 [95% CI, 0.29-0.64]; P=0.0001), deaths (OR=0.64 [95% CI, 0.49-0.83], P<0.0009), systemic bleeding (n=8387, OR=0.73 [95% CI, 0.54-0.99]; P=0.04), but increased headache and palpitations, compared with placebo, aspirin, or clopidogrel. Cilostazol reduced recurrent ischemic stroke more when given long (>6 months) versus short term without increasing hemorrhage, and in trials with larger proportions (>40%) of lacunar stroke. Data were insufficient to assess effects on cognition, imaging, functional outcomes, or tolerance.

CONCLUSIONS

Cilostazol appears effective for long-term secondary stroke prevention without increasing hemorrhage risk. However, most trials related to Asia-Pacific patients and more trials in Western countries should assess its effects on cognitive decline, functional outcome, and tolerance, particularly in lacunar stroke and other presentations of small vessel disease.

Progress in the Mechanism and Clinical Application of Cilostazol

Cilostazol is a unique platelet inhibitor that has been used clinically for more than 20 years. As a phosphodiesterase type III inhibitor, cilostazol is capable of reversible inhibition of platelet aggregation and vasodilation, has antiproliferative effects, and is widely used in the treatment of peripheral arterial disease, cerebrovascular disease, percutaneous coronary intervention, etc. This article briefly reviews the pharmacological mechanisms and clinical application of cilostazol.

Pre-clinical to Clinical Translational Failures and Current Status of Clinical Trials in Stroke Therapy: A Brief Review

In stroke (cerebral ischemia), despite continuous efforts both at the experimental and clinical level, the only approved pharmacological treatment has been restricted to tissue plasminogen activator (tPA). Stroke is the leading cause of functional disability and mortality throughout worldwide. Its pathophysiology starts with energy pump failure, followed by complex signaling cascade that ultimately ends in neuronal cell death. Ischemic cascade involves excessive glutamate release followed by raised intracellular sodium and calcium influx along with free radicals' generation, activation of inflammatory cytokines, NO synthases, lipases, endonucleases and other apoptotic pathways leading to cell edema and death. At the pre-clinical stage, several agents have been tried and proven as an effective neuroprotectant in animal models of ischemia. However, these agents failed to show convincing results in terms of efficacy and safety when the trials were conducted in humans following stroke. This article highlights the various agents which have been tried in the past but failed to translate into stroke therapy along with key points that are responsible for the lagging of experimental success to translational failure in stroke treatment.

Cilostazol Mono and Combination Treatments in Ischemic Stroke: An Updated Systematic Review and Meta-Analysis

Background and Purpose- We performed a systematic review and meta-analysis to explore the efficacy and safety of cilostazol as a mono or combination (plus aspirin or clopidogrel) treatments compared to conventional single antiplatelet therapy (SAPT, mainly aspirin) for secondary stroke prevention. Methods- Randomized controlled trial studies were searched across multiple comprehensive databases (MEDLINE, EMBASE, and Cochrane) for review. The primary outcome was recurrent stroke comprising ischemic and hemorrhagic stroke. Secondary outcomes included ischemic stroke, hemorrhagic stroke, myocardial infarction, and composite outcomes. We performed an updated systematic review and meta-analysis of the identified reports, including 2 recently published randomized controlled trials. In addition, network meta-analysis was performed to compare the relative effects of mono versus combination cilostazol treatments. Results- Ten studies were included in this review, 5 of which were assigned to the cilostazol mono group (n=5429) and the other 5 to the combination group (n=2456). The relative risks of recurrent stroke, ischemic stroke, and composite outcomes with cilostazol mono as well as combination treatments were significantly lower than with SAPT without any significant heterogeneity. An indirect comparison of these 3 outcomes revealed the cilostazol combination approach to be superior. The cilostazol mono treatment diminished hemorrhagic stroke more significantly than SAPT and the cilostazol combination did not increase hemorrhagic stroke compared to SAPT. The outcomes from the 2 cilostazol regimens were comparable to SAPT in the case of myocardial infarction. Conclusions- Cilostazol is a more effective and safer treatment option than SAPT approaches using mainly aspirin. Cilostazol regimens can also be modified to clinical situations as this drug reduces recurrent and ischemic stroke more efficiently as a combination therapy but is more beneficial for hemorrhagic stroke as a monotherapy.

Acute Aspirin Plus Cilostazol Dual Therapy for Noncardioembolic Stroke Patients Within 48 Hours of Symptom Onset

Background

The aim of the present study was to investigate the efficacy and safety of antiplatelet (aspirin plus cilostazol) dual therapy for patients with noncardioembolic stroke within 48 hours of symptom onset.

Methods and Results

The ADS (Acute Aspirin Plus Cilostazol Dual Therapy for Non‐Cardiogenic Stroke Patients Within 48 Hours of Symptom Onset ) study is an investigator‐initiated, prospective, multicenter (34 hospitals in Japan), randomized, open‐label, and aspirin‐controlled trial. Acute stroke patients with noncardioembolic stroke within 48 hours of onset were studied. The subjects were randomly allocated to combination therapy with aspirin 81 to 200 mg plus cilostazol 200 mg (dual group) and single therapy with aspirin 81 to 200 mg (aspirin group) for 14 days. After the 14 days, all patients took the cilostazol 200 mg for 3 months. A primary efficacy outcome was defined as any one of the following occurring (neurological deterioration, symptomatic stroke recurrence, or transient ischemic attack) within 14 days. A primary safety outcome included intracerebral hemorrhage and subarachnoid hemorrhage. Between May 2011 and June 2017, 1201 patients (796 [66%] men; median age, 69 [61–77] years) randomized 1:1 to either the dual group or the aspirin group were analyzed. Initial National Institutes of Health Stroke Scale score was 2 (1–4) in both groups (P=0.830). A primary efficacy outcome was observed in 11% in the dual group and 11% in the aspirin group (P=0.853). A primary safety outcome occurred in 2 (0.3%) in the dual group and in 1 (0.2%) in the aspirin group (P=0.624).

Conclusions

Dual antiplatelet therapy using cilostazol and aspirin was safe but did not reduce the rate of short‐term neurological worsening.

Clinical Trial Registration

URL: umin.ac.jp/ctr/index/htm. Unique identifier: UMIN000004950.

Antiplatelet therapy after stroke: should it differ in the acute and chronic phase after stroke

PURPOSE OF REVIEW

Reviewing existing evidence regarding well tolerated and effective antiplatelet treatment in patients with acute or chronic, noncardioembolic ischemic stroke and transient ischemic attack (TIA).

RECENT FINDINGS

For patients with high-risk stroke or TIA, for instance, minor stroke or high-risk TIA, or stroke of atherosclerotic origin with evidence suggesting risk of artery-to-artery embolism or with high-grade, symptomatic arterial stenosis, early initiated, short-term dual antiplatelet (e.g. aspirin and clopidogrel) is effective in reducing the risk of recurrent stroke and other vascular events which does not increase the risk of severe or fatal bleeding, as compared with mono antiplatelet therapy. However, long-term application of aggressive antiplatelet therapies after a noncardioembolic stroke or TIA increases the bleeding risks. Triple antiplatelet therapy is not appropriate for noncardioembolic stroke or TIA, in view of the high bleeding risk. In addition, emerging antiplatelets such as ticagrelor and cilostazol may work better in certain subgroups of stroke patients, which warrants further investigation.

SUMMARY

Antiplatelet therapies should differ in the acute and chronic phases among patients with high-risk stroke or TIA when more aggressive antiplatelet treatment is reasonable in the acute phase, but no solid evidence supports different antiplatelet strategies in acute and chronic phases in patients with low-risk noncardioembolic stroke.

Aspirin plus dipyridamole has the highest surface under the cumulative ranking curves (SUCRA) values in terms of mortality, intracranial hemorrhage, and adverse event rate among 7 drug therapies in the treatment of cerebral infarction

BACKGROUND

The standardization for the clinical use of drug therapy for cerebral infarction (CI) has not yet determined in some aspects. In this paper, we discussed the efficacies of different drug therapies (aspirin, aspirin plus dipyridamole, aspirin plus clopidogrel, aspirin plus warfarin, cilostazol, warfarin, and ticlopidine) for CI.

METHODS

We searched databases of PubMed and Cochrane Library from the inception to April, 2017, randomized controlled trials (RCTs) met the inclusion and exclusion criteria were enrolled in this study. The network meta-analysis integrated evidences of direct and indirect comparisons to assess odd ratios (OR) and surface under the cumulative ranking curves (SUCRA) value.

RESULTS

Thirteen eligible RCTs including 7 drug therapies were included into this network meta-analysis. The network meta-analysis results showed that CI patients who received aspirin plus dipyridamole presented lower mortality when compared with those received aspirin plus clopidogrel (OR = 0.46, 95% CI = 0.18-0.99), indicating aspirin plus dipyridamole therapy had better efficacy for CI. As for intracranial hemorrhage (ICH), stroke recurrence, and adverse event (AE) rate, there were no significant differences of efficacy among 7 drug therapies. Besides, SUCRA values demonstrated that in the 7 drug therapies, aspirin plus dipyridamole therapy was more effective than others (mortality: 80.67%; ICH: 76.6%; AE rate: 90.2%).

CONCLUSIONS

Our findings revealed that aspirin plus dipyridamole therapy might be the optimum one for patients with CI, which could help to improve the survival of CI patients.

Clopidogrel loading dose versus maintenance dose to treat patients with acute ischaemic stroke in China (CLASS-China): results from a prospective double-blind randomised clinical trial

AIM

The role of clopidogrel in treating patients with acute ischaemic stroke is unclear. We have conducted the clinical trial in order to evaluate the efficacy and safety of clopidogrel with a loading dose in treating patients with non-cardiogenic acute ischaemic stroke.

METHOD

Clopidogrel loading dose versus maintenance dose to treat patients with acute ischaemic stroke in China (CLASS-China) was a prospective, randomised, double-blind and placebo-controlled clinical trial in China. Patients with acute ischaemic stroke of non-cardiogenic origin within 48 hours of onset were enrolled and those received thrombolysis were excluded. Enrolled patients were divided into two treatment groups: loading dose and routine dose. The primary outcome was the incidence of stroke recurrence or progression within 7 days. Primary safety outcome was measured by life-threatening haemorrhage. An intent-to-treat analysis was used for the statistical analysis.

RESULTS

From March 2008 to March 2010, a total of 303 patients from 16 centres were recruited into this study; six were excluded because of lack of basic information. Since the enrolment was slow and the study drug expired in March 2010, this clinical trial was stopped earlier than planned. No significant baseline and demographic differences were seen between the two groups. There was no difference in primary outcome between the loading dosage group 16.1% (24/149) and control group 14.9% (22/148), respectively (p=0.782). The mortality and disability rate within 90 days in loading dose group (19.6%) was slightly lower than that in controlled group (23.4%), p=0.444. Loading dose group had two (1.3%) cases of fatal haemorrhage and control group had four (2.7%) within 90 days, p=0.674. No significant difference was detected in other adverse events between the groups.

CONCLUSION

In our study stopped early due to slow enrolment, loading dose of clopidogrel does not reduce the risk of recurrent stroke. Future trials with sufficient number of patients enrolled are needed to re-examine this hypothesis.

Preventing cognitive decline and dementia from cerebral small vessel disease: The LACI-1 Trial. Protocol and statistical analysis plan of a phase IIa dose escalation trial testing tolerability, safety and effect on intermediary endpoints of isosorbide mononitrate and cilostazol, separately and in combination

Rationale

The pathophysiology of most lacunar stroke, a form of small vessel disease, is thought to differ from large artery atherothrombo- or cardio-embolic stroke. Licensed drugs, isosorbide mononitrate and cilostazol, have promising mechanisms of action to support their testing to prevent stroke recurrence, cognitive impairment, or radiological progression after lacunar stroke.

Aim

LACI-1 will assess the tolerability, safety, and efficacy, by dose, of isosorbide mononitrate and cilostazol, alone and in combination, in patients with ischemic lacunar stroke.

Sample size

A sample of 60 provides 80+% power (significance 0.05) to detect a difference of 35% (90% versus 55%) between those reaching target dose on one versus both drugs.

Methods and design

LACI-1 is a phase IIa partial factorial, dose-escalation, prospective, randomized, open label, blinded endpoint trial. Participants are randomized to isosorbide mononitrate and/or cilostazol for 11 weeks with dose escalation to target as tolerated in two centers (Edinburgh, Nottingham). At three visits, tolerability, safety, blood pressure, pulse wave velocity, and platelet function are assessed, plus magnetic resonance imaging to assess cerebrovascular reactivity in a subgroup.

Study outcomes

Primary: proportion of patients completing study achieving target maximum dose.

Secondary

symptoms whilst taking medications; safety (hemorrhage, recurrent vascular events, falls); blood pressure, platelet function, arterial stiffness, and cerebrovascular reactivity.

Discussion

This study will inform the design of a larger phase III trial of isosorbide mononitrate and cilostazol in lacunar stroke, whilst providing data on the drugs’ effects on vascular and platelet function.

Trial registration

ISRCTN (ISRCTN12580546) and EudraCT (2015-001953-33).

Cilostazol improves endothelial function in acute cerebral ischemia patients: a double-blind placebo controlled trial with flow-mediated dilation technique

Background

In order to evaluate the impact of cilostazol on endothelial function, we compared the changes of flow-mediated dilation (FMD) between aspirin and cilostazol groups in patients with acute cerebral ischemia.

Methods

Patients presenting with acute cerebral ischemic events were randomly assigned into aspirin (n = 40) or cilostazol (n = 40) group in a double-blinded manner. FMD was measured at baseline (T0) and 90 days (T1). We measured L-arginine at baseline (a precursor of biologically active nitric oxides). Serious and non-serious adverse events were described.

Results

Despite no difference in the baseline FMD values (p = 0.363), there was a significant increase of FMD values in cilostazol group (7.9 ± 2.4 to 8.9 ± 2.3%, p = 0.001) and not in aspirin group (8.5 ± 2.6 to 9.3 ± 2.8%, p = 0.108). In the multiple regression analysis performed in cilostazol group, serum L–arginine levels were inversely correlated with FMD at T1 (ß = −0.050, SE: 0.012, p < 0.001) with age, total cholesterol levels, and C-reactive protein as confounders. While T0 FMD values in both aspirin and cilostazol groups did not show any correlation with serum L-arginine levels, the correlation is restored in the cilostazol group at T1 (r = 0.467, p = 0.007), while such is not shown in the aspirin group. There was no difference of serious adverse events between the two groups (p = 0.235). Adverse events were more common in the cilostazol group (35/40 vs. 25/40, p = 0.010), due to frequent headaches (14/40 vs. 3/30, p = 0.003) which was well tolerated.

Conclusion

Cilostazol improved endothelial function in acute cerebral ischemia patients. It also restored an inverse correlation between 3-month FMD and baseline L-arginine levels.

Trial registration

NCT03116269, 04/12/2017, retrospectively registered.

Electronic supplementary material

The online version of this article (10.1186/s12883-017-0950-y) contains supplementary material, which is available to authorized users.

Improved thrombolytic effect with focused ultrasound and neuroprotective agent against acute carotid artery thrombosis in rat

Combination therapy with focused ultrasound (FUS) and a neuroprotective agent, BNG-1, was examined in an acute carotid thrombotic occlusion model using LED irradiation in rat to improve the thrombolytic effect of rt-PA. Seven treatment groups included (A) intravenous bolus injection of 0.45 mg/kg rt-PA, (B) intravenous bolus injection of 0.9 mg/kg, (C) sonothrombolysis with FUS alone, (D) oral administration of 2 g/kg BNG-1 for 7 days alone, (E) A + D, (F) A + C, and (G) A + C + D. Four comparison groups were made including (H) 0.45 mg/kg rt-PA 20% bolus +80% IV fusion + FUS, (I) 0.9 mg/kg rt-PA with 10% bolus + 90% intravenous fusion, (J) B + C, (K) B + D. At 7 days after carotid occlusion, small-animal carotid ultrasound and 7 T MR angiography showed the recanalization rate of ≤50% stenosis was 50% in group B and 83% in group I, but 0% in groups A and C and 17% in group D. Combination therapy improved recanalization rate to 50–63% in groups E and F, to 67–83% in groups J and K, and to 100% in groups G and H. Our study demonstrated combination therapy with different remedies can be a feasible strategy to improve the thrombolytic effect of rt-PA.

Comparative efficacy and safety of antiplatelet agents in cerebral ischemic disease: A network meta-analysis

We performed a network meta-analysis (NMA) to enhance the corresponding evidence of the relative efficacy and safety of different antiplatelet agents in cerebral ischemic disease. PubMed and EMBASE were searched systematically for relevant studies. Outcomes were compared using odds ratios and 95% credible intervals. Each agent was ranked according to the value of surface under the cumulative ranking curve (SUCRA). Publication bias was evaluated by funnel plots, while consistency between direct and indirect comparison was analyzed by node-splitting and heat plots. Besides, the clustering technique was used to categorize similar agents. A number of 44 eligible studies with 148 578 patients were included in this NMA. In terms of efficacy (including mortality, recurrent stroke, and vascular event), all six interventions were better than placebo. clopidogrel (Clop) and aspirin (ASA)+Clop were the best two interventions from SUCRA. However, the performance of ASA+Clop declined significantly when considering safety (including myocardial infarction, all-cause withdrawal, and intracranial hemorrhage), especially worse in intracranial hemorrhage. In conclusion, Clop was potentially the most preferable treatment for preventing cerebral ischemic in terms of efficacy and safety. However, the addition of ASA was associated with a potential increase in intracranial hemorrhage, therefore, combination therapy of ASA and Clop should be introduced with caution although it may be more effective than the monotherapy of ASA.

Antiplatelet regimens in the long-term secondary prevention of transient ischaemic attack and ischaemic stroke: an updated network meta-analysis

OBJECTIVE

To examine the comparative efficacy and safety of different antiplatelet regimens in patients with prior non-cardioembolic ischaemic stroke or transient ischaemic attack.

DESIGN

Systematic review and network meta-analysis.

DATA SOURCES

As on 31 March 2015, all randomised controlled trials that investigated the effects of antiplatelet agents in the long-term (≥ 3 months) secondary prevention of non-cardioembolic transient ischaemic attack or ischaemic stroke were searched and identified.

OUTCOME MEASURES

The primary outcome measure of efficacy was serious vascular events (non-fatal stroke, non-fatal myocardial infarction and vascular death). The outcome measure of safety was any bleeding.

RESULTS

A total of 36 randomised controlled trials (82,144 patients) were included. Network meta-analysis showed that cilostazol was significantly more effective than clopidogrel (OR 0.77, 95% credible interval 0.60-0.98) and low-dose (75-162 mg daily) aspirin (0.69, 0.55-0.86) in the prevention of serious vascular events. Aspirin (50 mg daily) plus dipyridamole (400 mg daily) and clopidogrel reduced the risk of serious vascular events compared with low-dose aspirin; however, the difference was not statistically significant. Furthermore, low-dose aspirin was as effective as higher daily doses. Cilostazol was associated with a significantly lower bleeding risk than most of the other regimens. Moreover, aspirin plus clopidogrel was associated with significantly more haemorrhagic events than other regimens. Direct comparisons showed similar results as the network meta-analysis.

CONCLUSIONS

Cilostazol was significantly more effective than aspirin and clopidogrel alone in the long-term prevention of serious vascular events in patients with prior non-cardioembolic ischaemic stroke or transient ischaemic attack. Cilostazol was associated with a significantly lower bleeding risk than low-dose aspirin (75-162 mg daily) and aspirin (50 mg daily) plus dipyridamole (400 mg daily). Low-dose aspirin was as effective as higher daily doses. However, further large, randomised, controlled, head-to-head trials are needed, especially in non-Asian ethnic groups.

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.

Clinical efficacy and safety of cilostazol: a critical review of the literature

Cilostazol is a unique antiplatelet agent that has been commercially available for over two decades. As a phosphodiesterase III inhibitor, it reversibly inhibits platelet aggregation yet also possesses vasodilatory and antiproliferative properties. It has been widely studied in a variety of disease states, including peripheral arterial disease, cerebrovascular disease, and coronary artery disease with percutaneous coronary intervention. Overall, cilostazol appears to be a promising agent in the management of these disease states with a bleeding profile comparable to placebo; even when combined with other antiplatelet agents, cilostazol does not appear to increase the rate of bleeding. Despite the possible benefit of cilostazol, its use is limited by tolerability as some patients often report drug discontinuation due to headache, diarrhea, dizziness, or increased heart rate. To date, it has been predominantly studied in the Asian population, making it difficult to extrapolate these results to a more diverse patient population. This paper discusses the evolving role of cilostazol in the treatment of vascular diseases.

Meta-Analysis of Studies Evaluating the Effect of Cilostazol on Major Outcomes After Carotid Stenting

PURPOSE

To evaluate the effect of cilostazol on major outcomes after carotid artery stenting (CAS).

METHODS

A systematic literature review was conducted conforming to established criteria in order to identify articles published prior to May 2015 evaluating major post-CAS outcomes in patients treated with cilostazol vs patients not treated with cilostazol. Major outcomes included in-stent restenosis (ISR) within the observation period, the revascularization rate, major/minor bleeding, and the myocardial infarction/stroke/death rate (MI/stroke/death) at 30 days and within the observation period. Data were pooled for all studies containing adequate data for each outcome investigated; effect estimates are presented as the odds ratios (ORs) and 95 confidence intervals (CI).

RESULTS

Overall, 7 studies pertaining to 1297 patients were eligible. Heterogeneity was low among studies so a fixed-effect analysis was conducted. Six studies (n=1233) were compared for the ISR endpoint, showing a significantly lower ISR rate with cilostazol treatment after a mean follow-up of 20 months (OR 0.158, 95% CI 0.072 to 0.349, p<0.001). Five studies (n=649) were compared regarding 30-day MI/stroke/death (OR 0.724, 95% CI 0.293 to 1.789, p=0.484) and 3 studies (n=1076) were analyzed regarding MI/stroke/death within the entire follow-up period (OR 0.768, 95% CI 0.477 to 1.236, p=0.276); no significant difference was found between the groups. Data on bleeding rates and revascularization rates post ISR were inadequate to conduct further analysis.

CONCLUSION

Cilostazol seems to decrease total ISR rates in patients undergoing CAS without affecting MI/stroke/death events, both in the early and late settings.

Cilostazol research in Asia: can it be applied to European and American patients?

Cilostazol is an antiplatelet drug often used in Asian countries like Korea, Japan, and China. However, it is rarely used in the west. Cilostazol inhibits phosphodiesterase, increases cyclic AMP concentrations, and consequently inhibits platelet aggregation. Interestingly, it also has vasodilatory activity, inhibits vascular smooth muscle proliferation, and protects the endothelium. Studies in Asia have shown that cilostazol is effective in the secondary prevention of stroke. Moreover, it is significantly less likely to cause bleeding complications than aspirin. Additional trials have shown that cilostazol is effective in the prevention of intracranial atherosclerosis progression. Unfortunately, cilostazol has rarely been studied in non-Asian stroke patients and, accordingly, the benefits of cilostazol are less well appreciated in Europe and America than in Asia. Although further studies are required, we suggest that at least some stroke patients (e.g., patients prone to bleeding, patients with intracranial atherosclerosis, etc.) may readily benefit from cilostazol regardless of ethnicity.

Efficacy and Safety of Cilostazol Therapy in Ischemic Stroke: A Meta-analysis

BACKGROUND

Antiplatelet therapy is recommended for patients who have experienced ischemic stroke. We performed a meta-analysis to compare the efficacy and safety of cilostazol with other antiplatelet therapies in patients with ischemic stroke.

METHODS

PubMed, EMBASE, MEDLINE, and the Cochrane Library were searched for randomized controlled trials published in English from May 1999 to May 2013. Clinical outcomes were compared by pooled and meta-regression analyses.

RESULTS

Nine studies involving 6328 patients satisfied our inclusion criteria. Stroke recurrence (including hemorrhagic and ischemic) with cilostazol use was 5.3% (157) versus 8.3% (248) in control group (risk ratio .63 [.52-.76], 95% confidence interval [CI]). Poststroke intracranial hemorrhage was .5% (16) with cilostazol versus 1.6% (46) in control group (risk ratio .36 [.21-.63], 95% CI). Poststroke extracranial bleeding complications occurred in 2.4% (66) of the patients taking cilostazol versus 3.9% (108) in control group (risk ratio .62 [.46-.83], 95% CI). No significant difference in cerebrovascular events (nonfatal stroke, intracranial hemorrhage, and transient ischemic attack) was found between the cilostazol group (8.2%, 246) versus control group (12.0%, 360; risk ratio .71 [.50-1.01], 95% CI). In addition, the cilostazol therapy brought about a nonsignificant reduction of cardiac adverse events (heart failure, myocardial infarction, and angina pectoris) comparing with control groups, with 3.8% (99) of the cilostazol group versus 4.7% (123) of control group (risk ratio, .81 [.62-1.04], 95% CI).

CONCLUSIONS

Cilostazol, alone or in combination with aspirin, significantly reduces stroke recurrence, poststroke intracranial hemorrhage, and extracranial bleeding in patients with a prior ischemic stroke as compared with other antiplatelet therapies.

The efficacy and safety of cilostazol for the secondary prevention of ischemic stroke in acute and chronic phases in Asian population--an updated meta-analysis

Backgrounds

While previous meta-analysis have investigated the efficacy of cilostazol in the secondary prevention of ischemic stroke, they were criticized for their methodology, which confused the acute and chronic phases of stroke. We present a new systematic review, which differs from previous meta-analysis by distinguishing between the different phases of stroke, and includes two new randomized, controlled trials (RCTs).

Methods

All RCTs investigating the effect of cilostazol on secondary prevention of ischemic stroke were obtained. Outcomes were analyzed by Review Manager, including recurrence of cerebral infarction (ROCI), hemorrhage stroke or subarachnoid hemorrhage (HSSH), all-cause death (ACD), and modified Rankin Scale score (mRS). The Grading of Recommendations Assessment, Development and Evaluation (GRADE) assessed the quality of the evidence.

Results

5491 patients from six studies were included in the current study. In secondary prevention of ischemic stroke in chronic phase, cilostazol was associated with a 47% reduction in ROCI (relative risk [RR] 0.53, 95% confidence interval [CI] 0.34 to 0.81, p = 0.003), while no significant difference in HSSH and ACD compared with placebo; and 71% reduction in HSSH (RR 0.29, 95% CI 0.15 to 0.56, p = 0.0002) compared with aspirin, but not in ROCI and ACD. In the secondary prevention of ischemic stroke in acute phase, cilostazol did not show any effect in the ROCI, HSSH, ACD and mRS compared to placebo or aspirin. The quality of the evidence from chronic phase was high or moderate, and those from acute phase were moderate or low when analyzed by GRADE approach.

Conclusion

Cilostazol provided a protective effect in the secondary prevention of the chronic phase of ischemic stroke.

Research on intracranial atherosclerosis from the East and west: why are the results different?

Intracranial atherosclerosis (ICAS) is a major cause of stroke worldwide and is more common in Asians than Caucasians. The study results from the East and West are generally similar, but notable differences exist. For example, studies from the East have reported that ICAS is associated with young age, whereas ICAS seems to be associated with old age in the West. Studies from the East have strongly suggested that mild ICAS associated with branch occlusion is one of the main causes of single subcortical infarction, whereas this aspect has not been considered in stroke classification systems developed in the West. While clopidogrel is commonly used in patients with large artery disease in the West, cilostazol has been more extensively studied and commonly used in ICAS patients in the East. A randomized controlled study from the West reported negative results regarding the efficacy of stenting in ICAS patients due largely to a relatively high rate of periprocedural adverse events, whereas research papers from the East have reported a relatively lower rate of complications. Studies to narrow these East-West gaps should be performed, including risk factor studies using homogenous ethnic populations, studies investigating appropriate classification systems, drug trials in different ethnic populations, and rigorous high standard randomized controlled studies on the efficacy of stenting in Eastern populations.

Oral antiplatelet therapy for acute ischaemic stroke

BACKGROUND

In people with acute ischaemic stroke, platelets become activated and can cause blood clots to form and block an artery in the brain, resulting in damage to part of the brain. Such damage gives rise to the symptoms of stroke. Antiplatelet therapy might reduce the volume of brain damaged by ischaemia and also reduce the risk of early recurrent ischaemic stroke, thereby reducing the risk of early death and improving long-term outcomes in survivors. However, antiplatelet therapy might also increase the risk of fatal or disabling intracranial haemorrhage.

OBJECTIVES

To assess the efficacy and safety of immediate oral antiplatelet therapy (that is started as soon as possible and no later than two weeks after stroke onset) in people with acute presumed ischaemic stroke.

SEARCH METHODS

We searched the Cochrane Stroke Group Trials Register (last searched 16 October 2013), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 4, 2013), MEDLINE (June 1998 to May 2013), and EMBASE (June 1998 to May 2013). In 1998, for a previous version of this review, we searched the register of the Antiplatelet Trialists' Collaboration, MedStrategy and contacted relevant drug companies.

SELECTION CRITERIA

Randomised trials comparing oral antiplatelet therapy (started within 14 days of the stroke) with control in people with definite or presumed ischaemic stroke.

DATA COLLECTION AND ANALYSIS

Two review authors independently applied the inclusion criteria and assessed trial quality. For the included trials, they extracted and cross-checked the data.

MAIN RESULTS

We included eight trials involving 41,483 participants. No new trials have been added since the last update.Two trials testing aspirin 160 mg to 300 mg once daily, started within 48 hours of onset, contributed 98% of the data. The risk of bias was low. The maximum follow-up was six months. With treatment, there was a significant decrease in death or dependency at the end of follow-up (odds ratio (OR) 0.95, 95% confidence interval (CI) 0.91 to 0.99). For every 1000 people treated with aspirin, 13 people would avoid death or dependency (number needed to treat 79). Antiplatelet therapy was associated with a small but definite excess of symptomatic intracranial haemorrhages, but this small hazard was significantly outnumbered by the benefit, the reduction in recurrent ischaemic stroke and pulmonary embolus.

AUTHORS' CONCLUSIONS

Antiplatelet therapy with aspirin 160 mg to 300 mg daily, given orally (or by nasogastric tube or per rectum in people who cannot swallow) and started within 48 hours of onset of presumed ischaemic stroke, reduced the risk of early recurrent ischaemic stroke without a major risk of early haemorrhagic complications; long-term outcomes were improved.

Homocysteine as a predictor of early neurological deterioration in acute ischemic stroke

BACKGROUND AND PURPOSE

Hyperhomocysteinemia is a well-known risk factor for vascular disease. However, its action, mechanism, and role in the acute phase of stroke have not been determined. We tried to determine whether an association existed between elevated serum homocysteine levels and early neurological deterioration (END) in patients with acute ischemic stroke.

METHODS

We performed a secondary analysis from the Cilostazol in Acute Ischemic Stroke Treatment (CAIST) trial, which was a double-blinded, randomized, multicenter trial, assessing the noninferiority of cilostazol over aspirin within 48 hours of an acute ischemic stroke. END was defined as an increase of ≥1 point in motor power or an increase of ≥2 points in the total National Institute of Health Stroke Scale score within 7 days.

RESULTS

The mean (±SD) serum homocysteine level was 11.4±4.7 μmol/L. Of the 396 patients studied, 57 (14.4%) patients worsened during the 7 days after inclusion. Most (68%) of the END cases occurred within the first 24 hours after treatment. High levels (>10.3 μmol/L) of serum homocysteine were independent predictors for END (third quartile odds ratio, 3.45; 95% confidence intervals, 1.25-9.50; P=0.016; fourth quartile odds ratio, 3.36; 95% confidence intervals 1.18-9.52; P=0.023) in multivariate analysis.

CONCLUSIONS

Patients with acute stroke with elevated serum homocysteine levels are at an increased risk for END.

Systematic study of cilostazol on secondary stroke prevention: a meta-analysis

BACKGROUND

To study the efficacy and safety of cilostazol on ischemic stroke prevention and treatment, systematic reviews of related clinical randomized controlled trials were analyzed.

METHODS

We searched the main databases for eligible trials including literature from January 1966 to November 2012 in MEDLINE, reports from 1980 to November 2012 in EMBASE, and all the studies published in EBSCO, Springer, Ovid, and Cochrane library citations. We also searched for keywords, including cilostazol and aspirin. RewMan 5.0 software was used to conduct the meta-analysis.

RESULTS

Our search yielded five eligible trials. The effects of cilostazol and aspirin on ischemic stroke prevention and treatment were almost equal (combined odds ratio (OR) 0.78, 95% confidence interval (CI) (0.59, 1.04)). Additionally, both magnetic resonance angiography (MRA) and transcranial Doppler (TCD) examination showed that cilostazol could significantly decrease the incidence of intracranial artery stenosis exacerbation (MRA: combined OR 0.22, 95% CI (0.07, 0.68); TCD: combined OR 0.17, 95% CI (0.05, 0.51)). In terms of adverse reactions, there were slightly fewer incidences of major bleeding with cilostazol than with aspirin (combined OR 0.38, 95% CI (0.24, 0.60)), and there was no difference in the number of heart palpitations between cilostazol and aspirin. However, the incidence of gastrointestinal disorders, dizziness, and headaches caused by cilostazol was greater.

CONCLUSIONS

Cilostazol might be a more effective and safer alternative to aspirin for patients with ischemic stroke. Further studies are required to confirm whether cilostazol is a suitable therapeutic option for secondary stroke prevention in larger cohorts of patients with ischemic stroke.

Meta-analysis of cilostazol versus aspirin for the secondary prevention of stroke

Aspirin is the most widely prescribed antiplatelet agent for the secondary prevention of stroke. Cilostazol, an antiplatelet and vasodilating agent, has shown promise for the secondary prevention of stroke. A systematic review and meta-analysis of randomized controlled trials using Ovid MEDLINE, PubMed, and Excerpta Medica (EMBASE) was searched up to October 2012. Four trials, in 3,917 patients, comparing cilostazol with aspirin were identified. Compared with aspirin, cilostazol was associated with a 73% reduction in hemorrhagic stroke (relative risk [RR] 0.27, 95% confidence interval [CI] 0.13 to 0.54, p = 0.0002), 28% reduction in the composite end point of stroke, myocardial infarction, or vascular death (RR 0.72, 95% CI 0.57 to 0.89, p = 0.003), and 48% reduction in total hemorrhagic events (RR 0.52, 95% CI 0.34 to 0.79, p = 0.002), with trend for lesser gastrointestinal bleeds (RR 0.60, 95% CI 0.34 to 1.06, p = 0.08). In conclusion, compared with aspirin, cilostazol is associated with significantly less hemorrhagic stroke, the combined end point of stroke, myocardial infarction, and vascular death, and total hemorrhagic events, with numerically fewer gastrointestinal bleeds when used for the secondary prevention of stroke.

Antiplatelet therapy for carotid artery stenting

Carotid artery stenting (CAS) is less invasive and has a lower incidence of systemic complications such as myocardial infarction compared with carotid endarterectomy. However, CAS is known to have a high incidence of ischemic complications due to distal thromboembolism. Progress has been made in the development of various distal protection devices and protection methods aimed at preventing thromboembolism. Similar to these methods, perioperative antiplatelet therapy is also able to play a very important role in the prevention of ischemic events. Dual antiplatelet therapy has become standard for perioperative management of CAS.

Quantification of errors in ordinal outcome scales using shannon entropy: effect on sample size calculations

Objective

Clinical trial outcomes often involve an ordinal scale of subjective functional assessments but the optimal way to quantify results is not clear. In stroke, the most commonly used scale, the modified Rankin Score (mRS), a range of scores (“Shift”) is proposed as superior to dichotomization because of greater information transfer. The influence of known uncertainties in mRS assessment has not been quantified. We hypothesized that errors caused by uncertainties could be quantified by applying information theory. Using Shannon’s model, we quantified errors of the “Shift” compared to dichotomized outcomes using published distributions of mRS uncertainties and applied this model to clinical trials.

Methods

We identified 35 randomized stroke trials that met inclusion criteria. Each trial’s mRS distribution was multiplied with the noise distribution from published mRS inter-rater variability to generate an error percentage for “shift” and dichotomized cut-points. For the SAINT I neuroprotectant trial, considered positive by “shift” mRS while the larger follow-up SAINT II trial was negative, we recalculated sample size required if classification uncertainty was taken into account.

Results

Considering the full mRS range, error rate was 26.1%±5.31 (Mean±SD). Error rates were lower for all dichotomizations tested using cut-points (e.g. mRS 1; 6.8%±2.89; overall p<0.001). Taking errors into account, SAINT I would have required 24% more subjects than were randomized.

Conclusion

We show when uncertainty in assessments is considered, the lowest error rates are with dichotomization. While using the full range of mRS is conceptually appealing, a gain of information is counter-balanced by a decrease in reliability. The resultant errors need to be considered since sample size may otherwise be underestimated. In principle, we have outlined an approach to error estimation for any condition in which there are uncertainties in outcome assessment. We provide the user with programs to calculate and incorporate errors into sample size estimation.