The impact of renin-angiotensin-aldosterone system inhibitors on the recurrence of chronic subdural hematoma: a systematic review and meta-analysis

This meta-analysis seeks to investigate the effects of renin-angiotensin-aldosterone system (RAAS) inhibitors on the recurrence of chronic subdural hematoma (cSDH). Following the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement, this study conducted a comprehensive online search across various databases, including PubMed, EMBASE, CINAHL, Web of Science, and Cochrane, without time restrictions. Two reviewers independently screened titles, abstracts, and full texts based on predetermined criteria, resolving any discrepancies through discussion or consultation with a third reviewer. The quality and risk of bias of the included studies were assessed using the Methodological Index for Non-Randomized Studies (MINORS) and Cochrane's tool for evaluating risk of bias in randomized controlled trials. Six studies aligned with the study objectives were included after a systematic search across 6 databases. The RAAS inhibitors group comprised 404 participants, while the control or placebo group included 1828 participants. Analysis for publication bias using the Egger test indicated no bias in the studies (P = 0.151). The odds ratio for cSDH recurrence with RAAS inhibitor use compared to non-use was reported as OR = 1.06; confidence interval 0.6-1.893, p-value = 0.818, showing no significant association between RAAS inhibitor use and cSDH recurrence. The results suggest no significant link between RAAS inhibitor use and cSDH recurrence. However, due to the limited number and design of studies, as well as the lack of clinical trials, further research is needed to determine the effectiveness of this treatment.