Real-world assessment of anti-platelet therapies for recurrent stroke prevention in non-atrial fibrillation Japanese patients after recent ischemic stroke or transient ischemic attack
Authors: Kang A , Jiang J , Li X , Li D , Schuler P , Saha S , Terasaka N 
Published: October 2022

Abstract

Background
Stroke is one of the leading causes of cardiovascular-related deaths and disability for adults in Japan and is more commonly seen among the elderly. The risks of developing a secondary stroke resulting in permanent damage after the incident ischemic stroke (IS)/transient ischemic stroke (TIA) are very high. It is critical to understand the treatment landscape for the secondary stroke prevention (SSP) and unmet needs of patients with prior IS/ TIA events.

Purpose
To evaluate the antiplatelet therapy (APT) treatment patterns for SSP after first hospitalization for IS/TIA events among the Japanese population.

Methods
Japan's Medical Data Vision (MDV) from Q12011 to Q22021 was used for this study. MDV is a hospital-based claims database covering approximately 35.5 million individuals in the inpatient and outpatient settings among 438 hospitals. Adult patients with an inpatient primary diagnosis of IS/TIA during the index period were identified. Patients require at least one medical claim each quarter within the 1 year before and after index date to ensure longitudinal analysis. Atrial fibrillation patients or patients on oral anticoagulant use were excluded. Patients' characteristics, treatment pattern and duration were evaluated.

Results
Of 18,948 patients in this study, the mean age was 75 years and 36.7% were female; 91.5% were treated with APT and 8.5% were untreated within 90 days of hospital discharge. Among 17,332 APT treated patients, 76.9% were initiated on single APT (SAPT), 22.7% were initiated on dual APT (DAPT), and &lt;1% were initiated on multiple APT (MAPT). The most used SAPT were aspirin (ASA; 33.2%), clopidogrel (28.7%) or cilostazol (14.8%) and the most used DAPT were ASA+clopidogrel (15.1%), ASA+cilostazol (4.2%) or cilostazol+clopidogrel (2.7%). The median duration of APT was 320, 414 and 411 days for patients who initiated ASA, clopidogrel and cilostazol, respectively. The median duration of APT for patients who initiated ASA+clopidogrel, ASA+cilostazol and cilostazol+clopidogrel was 298, 359 and 473 days respectively. Of patients initiated on ASA+clopidogrel, 52.4% were de-escalated to SAPT (71% clopidogrel, 29% ASA; median duration of 20 days); 36.2% of patients initiated on ASA+cilostazol were de-escalated to SAPT within a median of 19 days (84% cilostazol, 16% ASA); lastly, 54.4% of patients initiated on cilostazol+clopidogrel de-escalated to SAPT within a median of 35 days (76% cilostazol, 24% clopidogrel). Two years after initial hospitalization of IS/TIA, 52%-56% discontinued APT treatments among those previously receiving SAPT while 46%-57% of patients receiving DAPT discontinued treatment.

Conclusion
Majority of patients at risk of secondary stroke received APT. Further analyses are needed to explore reasons for early APT discontinuation, for no APT use, and to evaluate outcomes of patients in this study.

Funding Acknowledgement
Type of funding sources: Private company. Main funding source(s): This study was sponsored by Bristol Myers Squibb and Janssen Research & Development, LLC. – Anonymised and used for statistical purposes only