A double-blind randomized control trial of transcranial direct current stimulation in post-stroke fatigue

Rationale Post-stroke fatigue (PSF) is an issue among stroke survivors that often impedes their rehabilitation progress. Treating PSF is challenging, and pharmacological interventions often prove ineffective. Aims The aim of this study was to examine the effect of tDCS on PSF. Sample size Thirty-four participants aged 30 to 80 with chronic stroke were recruited and randomly assigned to one of two groups, with 17 participants in each group. Methods and design This study was a double-blind randomized controlled trial. The sham group received sham tDCS, while the treatment group received active tDCS. The active tDCS treatment consisted of applying a constant 2-mA current through a 5 cm × 5 cm anodal electrode placed over the C3 or C4 positions (motor cortex) of the contralateral hemisphere of the scalp, with the cathodal electrode placed on the ipsilateral arm. The participants received two 20-min sessions of this treatment, separated by a 10-min interval, each day for 5 consecutive days. Sham tDCS involved the same setup but with only 30 s of constant current at the beginning and end of each 20-min session. Follow-up assessments were conducted over an 8-week period. The effects of tDCS were calibrated using an analysis of covariance approach, with baseline Modified Fatigue Impact Scale (MFIS) scores, age, and education as covariates. The inclusion criteria were (1) either sex; (2) age 30–80 years; (3) prior stroke diagnosis verified through brain imaging (computed tomography scan/magnetic resonance imaging); (4) Chinese ethnicity and Cantonese proficiency; (5) willingness and ability to provide informed consent; (6) presence of PSF (Fatigue Severity Scale score ≥ 4.0); and (7) at least 6 months post-stroke. Study outcome The primary outcome was the change in fatigue severity, assessed using the MFIS. Results One participant in the sham group dropped out. After the intervention, no significant changes were observed in MFIS scores at any of the follow-up timepoints ( p 0.05). Conclusion We found no evidence that the use of tDCS improves PSF. Further research is needed to explore the potential of this non-invasive brain stimulation method for the treatment of PSF. Clinical trial registration https://clinicaltrials.gov/ , identifier NCT04238260; https://www.chictr.org.cn/ , identifier ChiCTR2100052515.