Dynamics of Immunological Parameters in Patients with Varying Severity of Ischemic Stroke in the Acute Period: Prospective Cohort Study

INTRODUCTION. Despite significant experience in studying the role of cytokines in the regulation of the mechanisms of ischemia, verification of biomarkers of the severity of ischemic stroke currently remains insufficiently covered. In this connection, assessment of the immunological status of patients in the acute period of ischemic stroke is a promising research direction of modern angioneurology. AIM. To evaluate the presence and dynamics of cytokines in the acute period of ischemic stroke in patients with mild and moderate severity of neurological deficit. MATERIALS AND METHODS. 128 patients diagnosed with ischemic stroke were examined. Stroke severity was measured according to the National Institutes of Health Stroke Scale (NIHSS). Depending on the NIHSS score, patients were divided into two groups: group 1 - 60 patients with mild severity (NIHSS <5 points), group 2 - 68 patients with moderate severity (NIHSS - 5-15 points) of ischemic stroke. Immunological diagnostics included assessment of plasma concentrations of IL-1b, IL-16, IL-8, GM-CSF, TNFα and IFN-g on days 1 and 14 of hospitalization. RESULTS. Assessment of serum cytokine concentrations at admission revealed a significant increase in the concentrations of IL-16 (p = 0.002), IL-6 (p = 0.026) and IFN-g (p = 0.021) in patients of group 2. On the day 14 of hospitalization, a significant (p < 0.0001) decrease in the concentrations of GM-CSF and IL-1b and an increase in the level of IFN-g was detected in patients of group 1; in patients of group 2 - a significant increase in GM-CSF concentrations (p < 0.0001). A comparative analysis of cytokine levels on the day 14 of hospitalization revealed higher levels of IFN-g (p < 0.0001), GM-CSF (p < 0.0001), IL-6 (p = 0.0036), IL-16 (p < 0.0001) and IL-1b (p = 0.0002) in patients of group 2 compared with patients of group 1. CONCLUSION. Concentrations of the cytokines IL-16, IL-6 and IFN-g were identified as indicators of the severity of ischemic stroke on the first day. The level and changes in the concentration of GM-CSF can be considered as a biomarker of the course of the acute period of ischemic stroke, regardless of the NIHSS indicator; a decrease in the concentration of IL-1b as a predictor of a favorable outcome, and an increase in IFN-g as an immunological indicator of the severity of atherothrombotic stroke. For a deeper understanding of the influence of identified immunological markers on the course and severity of ischemia, further prospective studies are needed to evaluate cytokines at different times from the development of ischemic stroke in patients with varying severity of neurological deficit.