Neutrophil-to-lymphocyte ratio on admission predicts early perihematomal edema growth after intracerebral hemorrhage.

Poor functional outcome is associated with perihematomal edema (PHE) expansion after intracerebral hemorrhage (ICH). The inflammatory response is crucial for the onset and progression of PHE. This study aimed to determine the connection between admission neutrophil-lymphocyte ratio (NLR) and early PHE development. We retrospectively analyzed patients with ICH admitted to the Chaohu Affiliated Hospital of Anhui Medical University from January 2021 to December 2022. The primary outcome measure was absolute PHE, defined as the volume of the follow-up PHE minus admission PHE. A semiautomated measurement tool (3D Slicer) was used to calculate the volumes of cerebral hematoma and cerebral edema. Spearman's correlation analysis determined the relationship between NLR and absolute PHE. The multiple linear regression model was constructed to analyze the predictive relation of admission NLR on early PHE expansion. A total of 117 patients were included. The median hematoma and PHE volumes on admission were 9.38 mL (interquartile range [IQR], 4.53-19.54) and 3.54 mL (IQR, 1.33-7.1), respectively. The median absolute PHE was 2.26 mL (IQR, 1.25-4.23), and the median NLR was 3.10 (IQR, 2.26-3.86). Spearman's correlation test showed a positive correlation between admission NLR and absolute PHE (r = .548, P < .001). Multiple linear regression analyses suggested that for every 1-unit increase in admission NLR (B = .176, SE = .043, Beta = .275, P < .001), there was a 0.176 mL increase in absolute PHE. Admission neutrophil-to-lymphocyte ratio (NLR) significantly and positively predicted early perihematomal edema (PHE) expansion.