Neutrophil to lymphocyte ratio and early seizures after ischemic stroke: A case-control study

Background: Early post-stroke seizures (EPSS) are associated with an increased risk of mortality and post-stroke epilepsy. This study aimed to identify potential risk factors for EPSS, focusing on blood parameters, such as the neutrophil-to-lymphocyte ratio (NLR), which is a biomarker for inflammation.

Methods: Patients treated for ischemic stroke between 2017 and 2019 were retrospectively identified. 44 of them had a first epileptic seizure within 7 days after the stroke. They were matched 1:2 for age and sex with controls who had a stroke but no EPSS. Information on demographics, stroke characteristics, and blood parameters were collected on admission. Logistic regression was used to identify variables associated with EPSS and the area under the receiver operating characteristic curve (AUROC) to estimate their predictive accuracy.

Results: The NLR value (p = 0.035), National Institutes of Health Stroke Scale (NIHSS) (p = 0.016) and cortical localization of stroke (p = 0.03) were significantly correlated with the occurrence of EPSS in univariate logistic regression. In multivariable logistic regression, after adjusting for age, sex, baseline NIHSS, and stroke localization, the NLR values [adjusted odds ratio 1.097, 95% confidence interval (CI): 1.005-1.197; p = 0.038] were independently associated with the occurrence of EPSS. The AUROC for NLR was 0.639 (95% CI: 0.517-0.761) with 2.98 as the best predictive cut-off value. There was a significant positive relationship between NLR and NIHSS, r_S(87) = 0.383, p = <0.001.

Conclusion: Higher NLR values were associated with increased risk of EPSS. This biomarker appears useful to assess the risk of developing EPSS.