AUTHOR=Tong Bin , Wang Junjie , Chen Jiarui , Zhang Qia , Xu Zhouhan , Yang Kaichuang , Chen Xiaomin TITLE=Elevated ApoC3 levels in cerebrospinal fluid predict poor outcomes in patients with aneurysmal subarachnoid hemorrhage JOURNAL=Experimental Biology and Medicine VOLUME=Volume 251 - 2026 YEAR=2026 URL=https://www.ebm-journal.org/journals/experimental-biology-and-medicine/articles/10.3389/ebm.2026.10827 DOI=10.3389/ebm.2026.10827 ISSN=1535-3699 ABSTRACT=Aneurysmal subarachnoid hemorrhage (aSAH) is a devastating condition associated with approximately 30% mortality and 20% severe disability among survivors. Delayed cerebral ischemia due to cerebral vasospasm and hydrocephalus significantly contribute to poor neurological outcomes. Currently, reliable biomarkers for early prediction of these complications remain lacking. In this study, 63 patients with a mean age of 59.7 ± 11.53 years were enrolled. Functional outcomes were assessed by the modified Rankin Scale (mRS). Cerebrospinal fluid (CSF) samples were obtained through lumbar drainage (LD) or external ventricular drainage (EVD) and analyzed by ELISA. The predictive value of biomarkers was evaluated using receiver operating characteristic (ROC) curve analysis. Elevated Apolipoprotein C-III (ApoC3) levels in CSF of aSAH patients were observed. Furthermore, increased ApoC3 concentrations were significantly associated with poor prognosis and an elevated risk of severe complications. At an optimal cutoff value of 4,463 ng/mL, patients with high ApoC3 levels exhibited significantly worse 3-month functional outcomes and a higher incidence of delayed cerebral ischemia and hydrocephalus. Monitoring ApoC3 levels in CSF may be beneficial for predicting complications such as delayed cerebral ischemia and hydrocephalus in patients with aSAH.