Efficacy of aspirin, clopidogrel, and ticlopidine in stroke prevention: A population-based case-cohort study in Taiwan

Antiplatelet Treatment Patterns and Outcomes for Secondary Stroke Prevention in the United Kingdom

INTRODUCTION

Stroke is a leading cause of death and disability worldwide. Antiplatelet therapies are recommended to reduce the risk of recurrent stroke in patients with ischemic stroke/transient ischemic attack (IS/TIA). This study evaluated outpatient antiplatelet treatment patterns and outcomes for secondary stroke prevention (SSP) among UK adults without atrial fibrillation who were hospitalized for IS/TIA.

METHODS

This retrospective observational study utilized data from the UK Clinical Practice Research Datalink linked with Hospital Episode Statistics data (01/01/2011-30/06/2019). Treatment patterns included type and duration of treatments. Treatment outcomes included IS, myocardial infarction, major bleeding, and cardiovascular-related and all-cause mortality. Descriptive statistics were reported.

RESULTS

Of 9270 patients, 13.9% (1292) might not receive antithrombotic therapy within 90 days of hospital discharge. Of 7978 patients who received antiplatelet therapies, most used clopidogrel (74.8%) or aspirin (16.7%) single antiplatelet therapy and clopidogrel + aspirin dual antiplatelet therapy (DAPT, 5.9%). At 1-year post-hospitalization, 36.9, 43.3, and 35.1% of those receiving these treatments discontinued them, respectively, and of the patients initiating DAPT, 62.3% switched to single antiplatelet therapy. At 1-year post-discharge, the incidence rate (per 100 person-years) of IS, myocardial infarction, major bleeding, cardiovascular-related mortality, and all-cause mortality among the treated were 6.5, 0.7, 4.1, 5.0, and 7.3, respectively, and among the untreated were 14.9, 0.7, 8.6, 28.1, and 39.8, respectively.

CONCLUSIONS

In the United Kingdom, 13.9% of patients hospitalized for stroke might not have any antiplatelet treatment to prevent secondary stroke; among the treated, clopidogrel, aspirin, and DAPT were commonly used. These study findings suggest that improved anti-thrombotic therapies for long-term SSP treatment are needed, which may lead to higher treatment and persistence rates and, therefore, improved outcomes in this population.

Antiplatelet Use in Ischemic Stroke

Objective:

A literature review of antiplatelet agents for primary and secondary stroke prevention, including mechanism of action, cost, and reasons for lack of benefit.

Data sources:

Articles were gathered from MEDLINE, Cochrane Reviews, and PubMed databases (1980-2021). Abstracts from scientific meetings were considered. Search terms included ischemic stroke, aspirin, clopidogrel, dipyridamole, ticagrelor, cilostazol, prasugrel, glycoprotein IIb/IIIa inhibitors.

Study selection and data extraction:

English-language original and review articles were evaluated. Guidelines from multiple countries were reviewed. Articles were evaluated independently by 2 authors.

Data synthesis:

An abundance of evidence supports aspirin and clopidogrel use for secondary stroke prevention. In the acute phase (first 21 days postinitial stroke), these medications have higher efficacy for preventing further stroke when combined, but long-term combination therapy is associated with higher hemorrhage rates. Antiplatelet treatment failure is influenced by poor adherence and genetic polymorphisms. Antiplatelet agents such as cilostazol may provide extra benefit over clopidogrel and aspirin, in certain racial groups, but further research in more diverse ethnic populations is needed.

Relevance to patient care and clinical practice:

This review presents the data available on the use of different antiplatelet agents poststroke. Dual therapy, recurrence after initiation of secondary preventative therapy, and areas for future research are discussed.

Conclusions:

Although good evidence exists for the use of certain antiplatelet agents postischemic stroke, there are considerable opportunities for future research to investigate personalized therapies. These include screening patients for platelet polymorphisms that confer antiplatelet resistance and for randomized trials including more racially diverse populations.