Can Daytime Transcranial Direct Current Stimulation Treatment Change the Sleep Electroencephalogram Complexity of REM Sleep in Depressed Patients? A Double-Blinded, Randomized, Placebo-Controlled Trial

Zhe Li; Xueli Zhao; Lingfang Feng; Yu Zhao; Wen Pan; Ying Liu; Ming Yin; Yan Yue; Xiaojia Fang; Guorui Liu; Shigeng Gao; Xiaobin Zhang; Norden Eh Huang; Xiangdong Du; Rui Chen

doi:10.3389/fpsyt.2022.851908

Can Daytime Transcranial Direct Current Stimulation Treatment Change the Sleep Electroencephalogram Complexity of REM Sleep in Depressed Patients? A Double-Blinded, Randomized, Placebo-Controlled Trial

Front Psychiatry. 2022 May 18:13:851908. doi: 10.3389/fpsyt.2022.851908. eCollection 2022.

Authors

Zhe Li^{1

2}, Xueli Zhao², Lingfang Feng², Yu Zhao², Wen Pan², Ying Liu², Ming Yin², Yan Yue², Xiaojia Fang², Guorui Liu², Shigeng Gao², Xiaobin Zhang², Norden Eh Huang³, Xiangdong Du², Rui Chen¹

Affiliations

¹ Sleep Center, The Second Affiliated Hospital of Soochow University, Suzhou, China.
² Sleep Center, Suzhou Psychiatric Hospital, The Affiliated Guangji Hospital of Soochow University, Suzhou, China.
³ AidiSciTech Research Institute, Nanjing, China.

Abstract

Study objectives: The purpose of this study was to determine the effects of daytime transcranial direct current stimulation (tDCS) on sleep electroencephalogram (EEG) in patients with depression.

Methods: The study was a double-blinded, randomized, controlled clinical trial. A total of 37 patients diagnosed with a major depression were recruited; 19 patients (13 females and 6 males mean age 44.79 ± 15.25 years) received tDCS active stimulation and 18 patients (9 females and 9 males; mean age 43.61 ± 11.89 years) received sham stimulation. Ten sessions of daytime tDCS were administered with the anode over F3 and the cathode over F4. Each session delivered a 2 mA current for 30 min per 10 working days. Hamilton-24 and Montgomery scales were used to assess the severity of depression, and polysomnography (PSG) was used to assess sleep structure and EEG complexity. Eight intrinsic mode functions (IMFs) were computed from each EEG signal in a channel. The sample entropy of the cumulative sum of the IMFs were computed to acquire high-dimensional multi-scale complexity information of EEG signals.

Results: The complexity of Rapid Eye Movement (REM) EEG signals significantly decreased intrinsic multi-scale entropy (iMSE) (1.732 ± 0.057 vs. 1.605 ± 0.046, P = 0.0004 in the case of the C4 channel, IMF 1:4 and scale 7) after tDCS active stimulation. The complexity of the REM EEG signals significantly increased iMSE (1.464 ± 0.101 vs. 1.611 ± 0.085, P = 0.001 for C4 channel, IMF 1:4 and scale 7) after tDCS sham stimulation. There was no significant difference in the Hamilton-24 (P = 0.988), Montgomery scale score (P = 0.726), and sleep structure (N1% P = 0.383; N2% P = 0.716; N3% P = 0.772) between the two groups after treatment.

Conclusion: Daytime tDCS changed the complexity of sleep in the REM stage, and presented as decreased intrinsic multi-scale entropy, while no changes in sleep structure occurred. This finding indicated that daytime tDCS may be an effective method to improve sleep quality in depressed patients. Trial registration This trial has been registered at the ClinicalTrials.gov (protocol ID: TCHIRB-10409114, in progress).

Keywords: depression; double-blinded; electroencephalogram; intrinsic multi-scale entropy; placebo-controlled trial; randomized; rapid eye movement; transcranial direct current stimulation.