Serum brain-derived neurotrophic factor (BDNF) level may predict the functional outcome of acute ischemic stroke patients

Due to the high prevalence, disability, and cost incurred by acute ischemic stroke, several parameters to predict the functional outcome of stroke have been developed. Brain-Derived Neurotrophic Factor (BDNF) is a protein that plays an important role in neuroplasticity after a stroke attack. Lower BDNF level was associated with increased risk of developing stroke and poor prognostic functional outcome in stroke patients. Here, we measured serum BDNF levels in the acute and chronic phases of acute ischemic stroke patients to see whether the level was changing and affecting the functional outcome. A hospital-based prospective cohort study was conducted in the three largest governmental hospitals in Yogyakarta, Indonesia. Acute ischemic stroke patients were consecutively recruited from June 2018 until July 2019. Serum BDNF level measurements using enzyme-linked immunosorbent assay (ELISA) and functional outcome assessments using Barthel Index (BI) were performed on the 5^th and 30^th days after stroke onset, representing the acute and chronic phases of stroke, respectively. Sixty-eight patients completed the study and were categorized into dependent (n=22) and independent (n=46) groups according to BI score on the 30^th day after stroke onset. The mean serum BDNF level in the acute phase of the independent group was significantly higher than the dependent group (27,152.28 vs 23,143.41; p=0.044). Similar results were also found in the measurement of serum BDNF levels in the chronic phase in which the mean serum BDNF level of the independent group was found to be significantly higher than the dependent group (27,526.48 vs 22,818.91; p=0.036). There were no significant changes in the measurement of serum BDNF level between the acute and chronic phases in both dependent and independent groups. Serum BDNF level, either in the acute or chronic phase of stroke onset, may predict the functional outcome of the acute ischemic stroke patients.