Abstract and Introduction
Background: Transcranial direct current stimulation (tDCS) is a promising tool for improving poststroke 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-MoCA10–17; P real=0.001 versus P sham=0.835, K-MoCA18–25; 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-MoCA10–17; P timexgroup=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 poststroke 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.
Graphic Abstract: A graphic abstract is available for this article.
Cognitive dysfunction after stroke is an unfavorable factor for long-term functional independence. tDCS has beneficial effects on neuropsychiatric pathologies, such as Alzheimer dementia, major depressive disorder, and schizophrenia related to cognitive function.[2,3] In addition, reports indicate that tDCS as well as cognitive training (CogTx)[4,5] has positive effects on poststroke sequelae including neglect, depression, and aphasia.[2,6,7] Therefore, beneficial effects of tDCS on cognitive function after stroke can be anticipated.
Recent research has focused on the convenience, feasibility, and effectiveness of telerehabilitation. A study reported that patients with stroke showed a decline in function after discharge from inpatient rehabilitation facilities. Owing to the pressure at rehabilitation institutions to reduce the length of inpatient stays, the rehabilitation treatment environment is frequently changing, and it is difficult to provide a suitable, familiar environment for patients. Furthermore, there are challenges to the continued provision of outpatient CogTx due to limited accessibility in rural areas.
Since in-home computerized cognition treatment is feasible, if patients can safely and appropriately use tDCS at home, the effectiveness of cognitive therapy could be increased. Depending on the degree of supervision and intervention, home-based tDCS can be divided into home-use tDCS, remotely supervised tDCS (RS-tDCS), and remotely controlled tDCS. In home-use tDCS, patients can control the mode or application time themselves and use the device without supervision. In RS-tDCS, patients cannot control the tDCS settings and receive online support from a supervisor to administer duration and intensity. In remotely controlled tDCS, the device is always monitored and only controlled by the supervisor. A certain level of intervention is required to reduce the possibility of misuse and abuse and for optimal application of tDCS.[2,13] Therefore, for efficiency and safety, RS-tDCS may be the most suitable option.
In studies applying home-based rehabilitation with RS-tDCS in patients with multiple sclerosis and Parkinson disease, groups undergoing RS-tDCS plus CogTx showed greater improvements in cognitive function than groups undergoing CogTx alone.[14,15] To date, few studies have investigated the home-based application of tDCS in patients with stroke, and research on its effectiveness and feasibility is needed.
To our knowledge, no studies have investigated the effectiveness of RS-tDCS in improving cognitive function in patients with stroke. In this pilot study, we aimed to explore whether tDCS combined with home-based CogTx has a cognitive-enhancing effect and to investigate the feasibility of RS-tDCS for patients with chronic stroke.
Stroke. 2022;53(10):2992-3001. © 2022 American Heart Association, Inc.