C-reactive protein to lymphocyte ratio is a prognostic factor for unfavorable outcomes following aneurysmal subarachnoid hemorrhage.

The present study aimed to use the C-reactive protein-to-Lymphocyte Ratio (CLR) to investigate the impact of inflammation-immune imbalance on the prognosis of aneurysmal Subarachnoid Hemorrhage (aSAH) patients. A total of 650 eligible aSAH patients were prospectively enrolled in this study. CLR was examined within 24 h after symptom onset and calculated by C-reactive protein levels (mg/L) divided by lymphocyte count (109/L). The main outcome was 3-month unfavorable functional outcomes (modified Rankin Scale score of 4‒6). The secondary outcome was all-cause death (modified Rankin Scale score of 6). Multivariable logistic-regression analysis was performed to explore the relationship between CLR and clinical outcomes. Univariate analysis revealed that elevated CLR levels were associated with poor functional outcomes (p = 0.03) and all-cause death (p < 0.01). After adjusting for potential confounding indices, higher CLR levels (> 6.02 mg/109) were significantly associated with increased risk of 3-month poor functional outcomes (adjusted Odds Ratios: 2.89 [95 % CI: 1.02‒8.17]), but not related to all-cause death (adjusted Odds Ratios: 1.46 [95 % CI: 0.56‒3.80]). CLR during the hyperacute phase after aSAH might not only be utilized as a reliable biomarker to predict clinical outcomes of aSAH but also provide promising insight into future research to develop tailored treatments targeting inflammation-immune imbalance.