Abstract
OBJECTIVE: Early rebleed after aneurysmal subarachnoid hemorrhage (aSAH) is a catastrophic complication associated with high mortality and poor neurological outcomes. While inflammatory dysregulation and vascular instability have been implicated in aneurysmal rupture, early biomarkers capable of identifying patients at heightened risk for rebleed remain limited. This study aimed to investigate the association between the neutrophil-to-high-density lipoprotein cholesterol ratio (NHR) upon admission and the risk of preoperative early rebleed in patients with aSAH. METHODS: We retrospectively analyzed 752 patients diagnosed with aSAH who met the inclusion criteria from a single tertiary center. NHR was calculated from peripheral blood samples obtained within 6 h of admission (< 24 h from ictus). Preoperative early rebleed was defined as new clinical deterioration with radiological confirmation of hemorrhage occurring within 72 h of aSAH ictus before aneurysm repair. The association between NHR and early rebleed was assessed using multivariable logistic regression, propensity score matching (PSM), and restricted cubic spline (RCS) models. Subgroup analyses were performed to evaluate consistency across clinical strata. RESULTS: Among the included patients, 36 (4.79%) experienced preoperative early rebleed. Elevated admission NHR was independently associated with increasing preoperative early rebleed risk after adjustment for Hunt-Hess grade, modified Fisher grade, and activated partial thromboplastin time (adjusted odds ratio per unit increase in NHR: 1.12, 95% confidence interval (CI) 1.05-1.20; P = 0.0005). Patients in the highest NHR tertile had a 3.25-fold increased risk compared to those in the lowest tertile. Receiver operating characteristic curve analysis showed moderate discrimination for preoperative rebleed (the area under the curve = 0.69, 95% CI 0.655-0.723, P < 0.001). This association remained robust across PSM-adjusted cohorts and clinical subgroups. RCS analysis revealed a linear dose-response relationship between high NHR and early rebleed risk. These associations remained consistent in PSM-adjusted cohorts and across clinical subgroups. CONCLUSIONS: A higher NHR at admission is positively correlated with the risk of preoperative early rebleed in patients with aSAH. By reflecting systemic inflammation and reduced vascular protection, NHR complements established clinical and radiological predictors and may assist in prioritizing treatment timing in acute aSAH management.