Relationship of changes in circulating BDNF and motor impairment following a stroke rehabilitation intervention

Research Objectives: To examine the association between changes in circulating [plasma/serum] brain-derived neurotrophic factor [BDNF] and motor impairment following a combined aerobic exercise [AEx] and virtual reality-based upper extremity [VR-UE] rehabilitation intervention in chronic stroke survivors.

Design: Single Group Intervention Study

Setting: Research Laboratory.

Participants: Individuals at least 6 months post-stroke (n=7) with moderate upper extremity impairment (29.7 ± 4.5)

Interventions: All participants received 18 sessions of combined AEx and VR-UE rehabilitation intervention. During each session participants completed 15 minutes of AEx, at an intensity of 70% heart rate reserve, followed by playing a VR-UE rehabilitation game called Duck Duck Punch [DDP] for approximately 20 minutes.

Main Outcome Measures: Pre- and post-intervention, participants undertook assessments for; 1) upper extremity impairment, evaluated with the Fugl-Meyer Upper Extremity Assessment [FMA-UE], and 2) blood samples for assessment of serum [S-] and plasma [P-] BDNF. Absolute changes were calculated for all measures and correlational analyses were performed.

Results: Following the intervention, participants demonstrated a 3.7± 6.0 improvement in FMA-UE scores and S- and P-BDNF increased 1.06±5.61 ng/mL and 0.12±0.31 ng/mL, respectively. Change in FMA-UE and S-BDNF were moderately associated (r = .67). Conversely, P-BDNF and FMA-UE were moderately inversely associated (r = -.48). Changes in S-BDNF and P-BDNF were moderately, inversely associated (r = - .53).

Conclusions: Contrasting relationships between changes in S- and P-BDNF and changes in UE impairment may suggest that S-BDNF and P-BDNF may represent different aspects of BDNF regulation. This potential mechanistic disparity should be considered in future work aiming to understand the role of BDNF in stroke rehabilitation.

Author(s) Disclosures: None to disclose