Assessment of Neuron-Specific Enolase and Brain-Derived Neurotrophic Factor Levels at Rehabilitation Stages in the Early and Late Recovery Periods of Ischemic Stroke

Objective. To monitor peripheral blood levels of neuron-specific enolase (NSE) and brain-derived neurotrophic factor (BDNF) and analyze mutual clinical-laboratory correlations in patients with ischemic stroke at the stages of medical rehabilitation in the early recovery period. Materials and methods. A total of 49 patients with ischemic stroke in the basin of the middle cerebral artery were investigated. The observation period was 90 days. Time points were day 1, day 14, day 45, and day 90. Assessments were on the following scales: the National Institutes of Health Stroke Scale (NIHSS), the Fugl-Meyer assessment (FMA), and the modified Rankin scale (mRS). NSE was assayed in serum by enzyme-linked immunosorbent assay and BDNF on a multiplex analyzer. Results. NSE Day1 was significantly higher in patients than in the reference group ( p Day1–controls < 0.001) with a tendency to a peak reduction on day 90 after stroke ( p Day1–90 < 0.001). BDNF Day1 was lower than that in the reference group ( p Day1–controls = 0.006), increased significantly by day 14 after stroke ( p Day1–14 < 0.001; p Day14–controls = 0.637). A negative correlational relationship was found between the reduction in NSE Day14 and an increase in BDNF Day14 ( r = –0.349, p = 0.050). A positive correlation relationship was found between the increase in BDNF Day14 and the decrease in the mRS Day14 score ( r = 0.499, p = 0.035). Outcomes in patients of group 1 (after rehabilitation stages I and II) on assessment scales were significantly better than those in patients discharged to out-patient follow-up after stage I, i.e., group 2 ( p < 0.05). In group 1, BDNF Day90 was no different from BDNF Day14 ( p Day14–90–Gr.1 = 0.170), while in group 2 it was significantly lower at the end of the early recovery period ( p Day14–90–Gr.2 = 0.002).