Long-term repetitive transcranial direct current stimulation in patients with disorders of consciousness: a preliminary study

ABSTRACT

Objectives

To investigate the effects of long-term repetitive transcranial direct current stimulation on patients with DOC in the subacute phase.

Methods

In a randomized, double-blind, controlled study, 33 patients were randomly assigned to the active or sham group, and 28 patients completed the study. Patients in the active group received anodal stimulation over the DLPFC, while patients in the sham group received placebo stimulation (20 min/day, 5 days/week, for 4 weeks). The level of consciousness among patients was assessed with the Coma Recovery Scale-Revised (CRS-R) at baseline and at the end of every week from the first to the fourth week.

Results

The CRS-R scores of both the active and sham groups showed a consistent increasing trend over time; however, the treatment effect of the active group was better than that of the sham group. In addition, there was a statistically significant difference in the total CRS-R score between the two groups at weeks 1, 2, 3 and 4. Moreover, 10 patients (71.4%) in the active group and 3 patients (21.4%) in the sham group were regarded as responders.

Conclusion

Long-term tDCS could improve the level of consciousness of patients with DOC in the subacute stage.

KEYWORDS:

• Transcranial direct current stimulation (tDCS)
• Disorders of consciousness (DOC)
• Minimally Conscious State (MCS)
• Unresponsive Wakefulness Syndrome/Vegetative State (UWS/VS)
• Coma Recovery Scale-Revised (CRS-R)

Acknowledgments

We thank the whole staff from the Department of Rehabilitation of the Second Hospital of Lanzhou University as well as the patients and their families. we also thank Dr. Xiang Anfeng of Yichang Hospital of Traditional Chinese Medicine for his guidance.

Disclosure statement

No potential conflict of interest was reported by the author(s).

CRediT authorship contribution statement

The first two authors contributed equally to this paper. Xiao Rong Cheng was responsible for paper conception and research design, data collection, statistical analysis, result interpretation and paper writing. Yi Bao Zhang was responsible for the design and statistical analysis of the paper. Deng Juan Sun was responsible for tDCS operation. Xiao Yun Peng and Ying Cun Bao was responsible for charge of data management. Man Xia Wang was responsible for quality control, supervision and management, Fang Zhang was responsible for quality control and proofreading.

Additional information

Funding

This work was supported by the Innovation Fund for Higher Education of Gansu Province (No. 2021B-029), Natural Science Foundation of Gansu Province (23JRRA0981), Youth Science and Technology Fund of Gansu Province (20JR10RA761), Cuiying Science and Technology Innovation Project of Lanzhou University Second Hospital (2020QN-16), Cuiying Science and Technology Innovation Project of Lanzhou University Second Hospital (CY2021-MS-B12), Cuiying Science and Technology Innovation Project of Lanzhou University Second Hospital (CY-2023-QY-B08) and Traditional Chinese Medicine Management Project of Gansu Province (GZKG-2020-47).