tDCS does not add effect to foot drop stimulator and gait training in improving clinical parameters and neuroplasticity biomarkers in chronic post-stroke: randomized controlled trial

Abstract

Background

Transcranial direct current stimulation (tDCS) and foot drop stimulators (FDS) are widely used for stroke rehabilitation. However, no study has investigated if tDCS could boost the effects of FDS and gait training in improving clinical parameters and neuroplasticity biomarkers of chronic post-stroke subjects.

Objective

To investigate the effects of combining tDCS and FDS on motor impairment, functional mobility, and brain-derived neurotrophic factor (BDNF) serum levels. Also, to evaluate the effects of this protocol on the insulin-like growth factor-1 (IGF-1), insulin growth factor–binding proteins-3 (IGFBP-3), interleukin (IL) 6 and 10, and tumor necrosis factor-α (TNF-α) levels.

Methods

Thirty-two chronic post-stroke individuals were randomized to tDCS plus FDS or sham tDCS plus FDS groups. Both groups underwent ten gait training sessions for two weeks using a FDS device and real or sham tDCS. Blood samples and clinical data were acquired before and after the intervention. Motor impairment was assessed by the Fugl-Meyer Assessment and functional mobility using the Timed up and Go test.

Results

Both groups improved the motor impairment and functional mobility and increased the BDNF levels. Both groups also increased the IL-10 and decreased the cortisol, IL-6, and TNF-α levels. No difference was observed between groups.

Conclusion

tDCS did not add effect to FDS and gait training in improving clinical parameters and neuroplasticity biomarkers in chronic post-stroke individuals. Only FDS and gait training might be enough for people with chronic stroke to modify some clinical parameters and neuroplasticity biomarkers.

Graphical Abstract

Keywords:

• Transcranial direct current stimulation
• stroke rehabilitation
• brain-derived neurotrophic factor
• neuronal plasticity

Authors’ contributions

Experimental design: M.J.C, A.S.P. Experimental procedures: M.J.C, S.M., K.H. Analysis of the data: M.J.C., G.P.D. Discussion and interpretation of the data: M.J.C., G.P.D., A.S.P. Wrote the manuscript: M.J.C. All the authors participated in critical revision the manuscript, added important intellectual content, and approved the final version.

Disclosure statement

Authors declare that the Össur Brazil/Porto Alegre company provided the WalkAide (Innovative Neurotronics, Austin, TX, USA) orthosis for this study. Authors did not receipt any additional financial support for this research, authorship, and/or publication of this article.

Additional information

Funding

This work was partially supported by Brazilian agency Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES, finance code 001).