Association between the neutrophil-to-lymphocyte ratio and neurological outcomes in patients undergoing targeted temperature management after cardiac arrest

Abstract

Purpose: This study aimed to elucidate the association between the neutrophil-to-lymphocyte ratio (NLR) and neurological outcomes in out-of-hospital cardiac arrest (OHCA) patients treated with targeted temperature management (TTM).

Materials and methods: A retrospective study was performed on patients treated with TTM after OHCA. Patients were divided into two groups according to their calculated NLRs (NLR < 6 and NLR ≥ 6). The primary outcome was poor neurological outcome at 6 months as defined by a Cerebral Performance Category between 3 and 5.

Results: A total of 216 were included and 131 subjects had poor neurological outcomes at 6 months. In the univariate model, NLRs ≥ 6 at 48 and 72 h after ROSC were associated with poor neurological outcomes (OR: 3.716, 95% CI: 1.243-11.114; OR: 7.429, 95% CI: 3.693-14.945, respectively). In the multivariate logistic regression analysis, an NLR ≥ 6 at 72 h was associated with poor neurological outcomes after adjusting for history of HTN, shockable rhythm, cardiac cause of arrest and time from collapse to ROSC and highest WBC, hs-CRP, lactate and pneumonia (OR = 3.299, 95% CI = 1.080-10.081).

Conclusions: An NLR ≥ 6 at 72 h after the ROSC is associated with poor neurological outcomes at 6 months after CA.

Keywords: Cardiac arrest; Hypothermia, induced; Neutrophil-to-lymphocyte ratio; Prognosis.