Home-Based Transcranial Direct Current Stimulation to Enhance Cognition in Stroke: Randomized Controlled Trial

Abstract

Background: Transcranial direct current stimulation (tDCS) is a promising tool for improving post-stroke cognitive function. Home-based rehabilitation is increasingly required for patients with stroke, and additional benefits are expected if supplemented with remotely supervised tDCS (RS-tDCS). We evaluated the cognitive improvement effect and feasibility of RS-tDCS in patients with chronic stroke. Methods: Twenty-six patients with chronic stroke and cognitive impairment (Korean version of the Montreal Cognitive Assessment [K-MoCA] score <26) were randomized into real and sham RS-tDCS groups and underwent concurrent computerized cognitive training and RS-tDCS. Patients and caregivers underwent training to ensure correct tDCS self-application, were monitored, and treated 5 d/wk for 4 weeks. We investigated several cognition tests including K-MoCA, Korean version of the Dementia Rating Scale-2, Korean-Boston Naming Test, Trail Making Test, Go/No Go, and Controlled Oral Word Association Test at the end of the training sessions and one month later. Repeated-measures ANOVA was used for comparison between the groups and within each group. The adherence rate of the appropriate RS-tDCS session was also investigated. Results: In within-group comparison, unlike the sham group, the real group showed significant improvement in K-MoCA ( P real =0.004 versus P sham =0.132), particularly in patients with lower baseline K-MoCA (K-MoCA 10–17 ; P real =0.001 versus P sham =0.835, K-MoCA 18–25 ; P real =0.060 versus P sham =0.064) or with left hemispheric lesions (left; P real =0.010 versus P sham =0.454, right; P real =0.106 versus P sham =0.128). In between-group comparison, a significant difference was observed in K-MoCA in the lower baseline K-MoCA subgroup (K-MoCA 10–17 ; P time×group =0.048), but no significant difference was found in other cognitive tests. The adherence rate of successful application of the RS-tDCS was 98.4%, and no serious adverse effects were detected. Conclusions: RS-tDCS is a safe and feasible rehabilitation modality for post-stroke cognitive dysfunction. Specifically, RS-tDCS is effective in patients with moderate cognitive decline. Additionally, these data demonstrate the potential to enhance home-based cognitive training, although significant differences were not consistently found in between-group comparisons; therefore, further larger studies are needed. REGISTRATION: URL: https://cris.nih.go.kr ; Unique identifier: KCT0003427.

Systematic review and network meta-analysis of effects of noninvasive brain stimulation on post-stroke cognitive impairment

“…A total of 814 studies were obtained, including 353 in English and 461 in Chinese. 18 studies (Kim et al, 2010 ; Lu et al, 2015 ; Yun et al, 2015 ; Shaker et al, 2018 ; Yin et al, 2018 ; Zeng et al, 2019 ; Zhang and Zou, 2019 ; Liu et al, 2020 , 2021 ; Li Y. et al, 2020 ; Ma et al, 2020 ; Ai et al, 2021 ; Li H. et al, 2021 ; Zhang et al, 2021 ; Chen et al, 2022 ; Ko et al, 2022 ; Li W. et al, 2022 ; Yan et al, 2022 ) were finally included, including 9 in English (Kim et al, 2010 ; Lu et al, 2015 ; Yun et al, 2015 ; Shaker et al, 2018 ; Liu et al, 2020 ; Li Y. et al, 2020 ; Li H. et al, 2021 ; Ko et al, 2022 ; Li W. et al, 2022 ) and 9 in Chinese (Yin et al, 2018 ; Zeng et al, 2019 ; Zhang and Zou, 2019 ; Ma et al, 2020 ; Ai et al, 2021 ; Liu et al, 2021 ; Zhang et al, 2021 ; Chen et al, 2022 ; Yan et al, 2022 ). The literature selection process is shown in Figure 1 .…”

“…Of the 18 studies, eight (Lu et al, 2015 ; Yin et al, 2018 ; Zeng et al, 2019 ; Zhang and Zou, 2019 ; Ai et al, 2021 ; Li H. et al, 2021 ; Liu et al, 2021 ; Zhang et al, 2021 ) used the number table method to generate random sequences, two (Liu et al, 2020 ; Ko et al, 2022 ) used a computer for randomized assignment. The remaining eight mentioned “random grouping” but did not specify the randomization method.…”

“…All studies were blinded to treatment participants. Ten studies (Kim et al, 2010 ; Yun et al, 2015 ; Yin et al, 2018 ; Zhang and Zou, 2019 ; Liu et al, 2020 , 2021 ; Li Y. et al, 2020 ; Ai et al, 2021 ; Ko et al, 2022 ; Li W. et al, 2022 ) were blinded to assessors. The results of all studies were complete and not selectively reported.…”

Home-Based Transcranial Direct Current Stimulation: Are We There Yet?

“…his editorial addresses the article by Ko et al, 1 published in Stroke, on the effectiveness of home transcranial direct current stimulation (tDCS) as an adjunct for previously shown effective in-home computerized cognition treatment for poststroke cognitive rehabilitation. 2 Previous studies, among which the largest is Fridriksson et al's 3 study of nonfutility in the use of tDCS in poststroke language rehabilitation (2018), 3 have advocated for further investigation of tDCS applications in poststroke rehabilitation, and the present study is a worthy sequel.…”

“…But is feasibility accompanied by effectiveness for nonlanguage cognitive rehabilitation? The preliminary study by Ko et al 1 provide an answer: “yes, under certain conditions.”…”