Comparison of the Safety of Aspirin Monotherapy and Aspirin and P2Y12 Inhibitor Combination Therapy in Patients Post Coil Embolization During Admission: A Cross-Sectional Study Using a Nationwide Inpatient Database.

Background: Some aspects regarding the use of antiplatelet agents after coil embolization for subarachnoid hemorrhage during admission remain unclear. This study used diagnostic procedure combination (DPC) data to investigate the safety and prognostic effects of aspirin monotherapy and aspirin and P2Y12 inhibitor combination therapy on bleeding events.
Methods: This cross-sectional study used Japanese DPC data to assess patients who were hospitalized with subarachnoid hemorrhage and received aspirin monotherapy and aspirin and P2Y12 inhibitor combination therapy between April 2016 and March 2020 (n = 4421). The aspirin monotherapy (A group, n = 2848) and aspirin and P2Y12 inhibitor combination therapy (AP group, n = 1573) groups were compared. The primary and secondary endpoints were the incidence of bleeding events and proportion of patients with a modified Rankin Scale (mRS) score ≤ 2 at discharge, respectively. Data was analyzed using multivariable adjusted logistic regression (significance level, 5%).
Results: The adjusted odds ratio in AP group, with A group as the reference, for bleeding events and the proportion of patients with mRS score ≤ 2 at discharge were 0.97 (95% confidence interval [95% CI]: 0.75-1.26, p = 0.839) and 1.09 (95% CI: 0.92-1.29, p = 0.302), respectively.
Conclusions: There are no differences in the incidence of bleeding events or good clinical outcomes (mRS score ≤ 2 at discharge) between aspirin monotherapy and aspirin and P2Y12 inhibitor combination therapy.
Competing Interests: Declarations. Funding: This study did not receive any specific grants from funding agencies in the public, commercial, or not-for-profit sectors. Conflicts of interest: Hiroshi Magara is an employee of Nxera Pharmaceuticals Japan Ltd. The other authors declare no conflicts of interest. Availability of data and materials: The data that support the findings of this study are not openly available due to reasons of sensitivity but are available from the corresponding author upon reasonable request. Ethics approval: The study protocol was approved by the Ethics Review Board of the Tokyo Medical and Dental University (approval number: M2000-788-33). This study involved secondary analyses of a claims database and did not directly involve participants. We did not involve patients in designing the research question, outcome measures, interpretation, or writing the results of this study. The participants were given the opportunity to opt out via the study website. Consent to Participate: The ethics review board of the Tokyo Medical and Dental University waived the need for informed consent because the study design involving secondary analyses of a claims database and did not directly involve participants (designing the research question, selecting the outcome measures, and interpreting and writing the results of this study). Participants were given the opportunity to opt out via the study website. Consent for publication: Not applicable. Code availability: Not applicable. Authors’ Contributions: Hiroshi Magara and Yuri Nakamura were responsible for conceptualization, methodology, data curation, writing: original draft preparation, visualization, and investigation; Takuaki Tani and Shinobu Imai were responsible for conceptualization, methodology, data analysis and writing: reviewing and editing; Anna Kiyomi and Kensuke Yoshida were responsible for conceptualization, methodology, and writing: reviewing and editing; Kiyohide Fushimi was responsible for conceptualization, data acquisition, and writing: reviewing and editing; and Munetoshi Sugiura was responsible for conceptualization, methodology, writing: reviewing and editing, and supervision. All the authors have read and approved the final version of the manuscript.
(© 2024. The Author(s).)