Triple versus guideline antiplatelet therapy to prevent recurrence after acute ischaemic stroke or transient ischaemic attack: the TARDIS RCT

Ninety-Day Stroke Recurrence in Minor Stroke: Systematic Review and Meta-Analysis of Trials and Observational Studies

BACKGROUND

Risk of recurrence after minor ischemic stroke is usually reported with transient ischemic attack. No previous meta-analysis has focused on minor ischemic stroke alone. The objective was to evaluate the pooled proportion of 90-day stroke recurrence for minor ischemic stroke, defined as a National Institutes of Health Stroke Scale severity score of ≤5.

METHODS AND RESULTS

Published papers found on PubMed from 2000 to January 12, 2021, reference lists of relevant articles, and experts in the field were involved in identifying relevant studies. Randomized controlled trials and observational studies describing minor stroke cohort with reported 90-day stroke recurrence were selected by 2 independent reviewers. Altogether 14 of 432 (3.2%) studies met inclusion criteria. Multilevel random-effects meta-analysis was performed. A total of 6 randomized controlled trials and 8 observational studies totaling 45 462 patients were included. The pooled 90-day stroke recurrence was 8.6% (95% CI, 6.5-10.7), reducing by 0.60% (95% CI, 0.09-1.1; P=0.02) with each subsequent year of publication. Recurrence was lowest in dual antiplatelet trial arms (6.3%, 95% CI, 4.5-8.0) when compared with non-dual antiplatelet trial arms (7.2%, 95% CI, 4.7-9.6) and observational studies 10.6% (95% CI, 7.0-14.2). Age, hypertension, diabetes, ischemic heart disease, or known atrial fibrillation had no significant association with outcome. Defining minor stroke with a lower National Institutes of Health Stroke Scale threshold made no difference - score ≤3: 8.6% (95% CI, 6.0-11.1), score ≤4: 8.4% (95% CI, 6.1-10.6), as did excluding studies with n<500%-7.3% (95% CI, 5.5-9.0).

CONCLUSIONS

The risk of recurrence after minor ischemic stroke is declining over time but remains important.

Acute Myocardial Infarction and Risk of Cognitive Impairment and Dementia: A Review

Cognitive impairment (CI) shares common cardiovascular risk factors with acute myocardial infarction (AMI), and is increasingly prevalent in our ageing population. Whilst AMI is associated with increased rates of CI, CI remains underreported and infrequently identified in patients with AMI. In this review, we discuss the evidence surrounding AMI and its links to dementia and CI, including pathophysiology, risk factors, management and interventions. Vascular dysregulation plays a major role in CI, with atherosclerosis, platelet activation, microinfarcts and perivascular inflammation resulting in neurovascular unit dysfunction, disordered homeostasis and a dysfunctional neurohormonal response. This subsequently affects perfusion pressure, resulting in enlarged periventricular spaces and hippocampal sclerosis. The increased platelet activation seen in coronary artery disease (CAD) can also result in inflammation and amyloid-β protein deposition which is associated with Alzheimer's Dementia. Post-AMI, reduced blood pressure and reduced left ventricular ejection fraction can cause chronic cerebral hypoperfusion, cerebral infarction and failure of normal circulatory autoregulatory mechanisms. Patients who undergo coronary revascularization (percutaneous coronary intervention or bypass surgery) are at increased risk for post-procedure cognitive impairment, though whether this is related to the intervention itself or underlying cardiovascular risk factors is debated. Mortality rates are higher in dementia patients with AMI, and post-AMI CI is more prevalent in the elderly and in patients with post-AMI heart failure. Medical management (antiplatelet, statin, renin-angiotensin system inhibitors, cardiac rehabilitation) can reduce the risk of post-AMI CI; however, beta-blockers may be associated with functional decline in patients with existing CI. The early identification of those with dementia or CI who present with AMI is important, as subsequent tailoring of management strategies can potentially improve outcomes as well as guide prognosis.

Comprehensive review of statistical methods for analysing patient-reported outcomes (PROs) used as primary outcomes in randomised controlled trials (RCTs) published by the UK's Health Technology Assessment (HTA) journal (1997-2020)

OBJECTIVES

To identify how frequently patient-reported outcomes (PROs) are used as primary and/or secondary outcomes in randomised controlled trials (RCTs) and to summarise what statistical methods are used for the analysis of PROs.

DESIGN

Comprehensive review.

SETTING

RCTs funded and published by the United Kingdom's (UK) National Institute for Health Research (NIHR) Health Technology Assessment (HTA) Programme.

DATA SOURCES AND ELIGIBILITY

HTA reports of RCTs published between January 1997 and December 2020 were reviewed.

DATA EXTRACTION

Information relating to PRO use and analysis methods was extracted.

PRIMARY AND SECONDARY OUTCOME MEASURES

The frequency of using PROs as primary and/or secondary outcomes; statistical methods that were used for the analysis of PROs as primary outcomes.

RESULTS

In this review, 37.6% (114/303) of trials used PROs as primary outcomes, and 82.8% (251/303) of trials used PROs as secondary outcomes from 303 NIHR HTA reports of RCTs. In the 114 RCTs where the PRO was the primary outcome, the most used PRO was the Short-Form 36 (8/114); the most popular methods for multivariable analysis were linear mixed model (45/114), linear regression (29/114) and analysis of covariance (13/114); logistic regression was applied for binary and ordinal outcomes in 14/114 trials; and the repeated measures analysis was used in 39/114 trials.

CONCLUSION

The majority of trials used PROs as primary and/or secondary outcomes. Conventional methods such as linear regression are widely used, despite the potential violation of their assumptions. In recent years, there is an increasing trend of using complex models (eg, with mixed effects). Statistical methods developed to address these violations when analysing PROs, such as beta-binomial regression, are not routinely used in practice. Future research will focus on evaluating available statistical methods for the analysis of PROs.

A Case of Failed Dual Antiplatelet Therapy With Oral Anticoagulant in the Prevention of Acute Ischemic Stroke

Cerebrovascular accidents (CVA) or strokes cause focal neurological deficits, which may be due to rupture or occlusion of blood vessels supplying areas of the brain. Atrial fibrillation (AF) is an independent and significant risk factor for ischemic CVA, mainly via the embolic pathway. This is evident as newly diagnosed patients with AF are typically started on anticoagulation therapy if their CHA2DS2-VASc score is equal to or greater than two. Furthermore, ischemic CVA may occur as a thrombotic phenomenon due to significant vessel atherosclerotic disease involving plaque ulceration and rupture. Such a phenomenon may be curtailed with antiplatelet therapy in at-risk patient populations, particularly as a form of secondary prevention. This case highlights the unfortunate incidence of an ischemic CVA in a patient using dual antiplatelet therapy (DAPT) and anticoagulation.

Efficacy and Safety of Using Dual Versus Monotherapy Antiplatelet Agents in Secondary Stroke Prevention: Systematic Review and Meta-Analysis of Randomized Controlled Clinical Trials

BACKGROUND

Dual antiplatelet treatment (DAPT) with aspirin plus clopidogrel for a limited time is recommended after minor noncardioembolic stroke.

METHODS

We performed a meta-analysis of all major studies that compared the efficacy and safety of DAPT versus monotherapy for the secondary prevention of recurrent stroke or transient ischemic attack. The primary outcomes were stroke and the composite of stroke, transient ischemic attack, acute coronary syndrome, and death from any cause. The safety outcome was major hemorrhage. Relative risk (RR) and 95% CIs were calculated. Heterogeneity was assessed by I² and Cochrane Q statistics.

RESULTS

The analysis included 27 358 patients, the quality of evidence was moderate to low, and the heterogeneity for all the comparisons was low (I²≤25%). Compared with monotherapy, DAPT reduced the risk of recurrent stroke (RR, 0.71 [95% CI, 0.63-0.81]) and composite outcome (RR, 0.76 [95% CI, 0.69-0.83]) but increased the risk of major bleeding (RR, 2.17 [95% CI, 1.45-3.25]). In the subgroup analysis, ≤30 days of DAPT increased the risk of hemorrhage relative to monotherapy (RR, 1.94 [95% CI, 1.08-3.52]). In the sensitivity analysis, the risk for hemorrhage with ≤30 days of DAPT after excluding the combination of aspirin plus ticagrelor was comparable to monotherapy (RR, 1.42 [95% CI, 0.77-2.60]). However, the risk for stroke recurrence and composite outcomes in the subgroup and sensitivity analyses remain decreased compared with monotherapy.

CONCLUSIONS

DAPT decreases the risk of recurrent stroke and composite events compared with monotherapy. DAPT increases the risk of major hemorrhage, except if the treatment is limited to 30 days and does not include the combination of aspirin plus ticagrelor.

Antiplatelet Therapy in the Secondary Prevention of Non-cardioembolic Ischemic Stroke and Transient Ischemic Attack: A Mini-Review

The aim of this mini-review is to discuss the main antiplatelet agents that have been successfully used in the secondary prevention of non-cardioembolic ischemic stroke and transient ischemic attacks (TIA). The methodology is based on a literature review of available peer-reviewed English studies listed in PubMed. The findings reveal that aspirin remains a reliable antiplatelet agent in the secondary prevention of acute non-cardioembolic ischemic stroke and TIA. Nevertheless, currently, there are also other agents, i.e., ticagrelor, clopidogrel, and cilostazol, that can be applied. In addition, the results indicate that time is significant not only in severe stroke but also in non-severe stroke and TIA, which suggests that antiplatelet therapy should be applied within 24 h after the first symptoms because early treatment can lead to an improvement in neurological outcomes and reduce the chance of an early subsequent stroke.