The effect of transcranial direct current stimulation (tDCS) on cognitive function recovery in patients with depression following electroconvulsive therapy (ECT): protocol for a randomized controlled trial.

BACKGROUND: Electroconvulsive therapy (ECT) is a highly effective treatment for depressive disorder. However, the use of ECT is limited by its cognitive side effects (CSEs), and no specific intervention has been developed to address this problem. As transcranial direct current stimulation (tDCS) is a safe and useful tool for improving cognitive function, the main objective of this study was to explore the ability to use tDCS after ECT to ameliorate the cognitive side effects.

METHODS: 60 eligible participants will be recruited within two days after completing ECT course and randomly assigned to receive either active or sham stimulation in a blinded, parallel-design trial and continue their usual pharmacotherapy. The tDCS protocol consists of 30-min sessions at 2 mA, 5 times per week for 2 consecutive weeks, applied through 15-cm2 electrodes. An anode will be placed over the left dorsolateral prefrontal cortex (DLPFC), and a cathode will be placed over the right supraorbital cortex. Cognitive function and depressive symptoms will be assessed before the first stimulation (T0), after the final stimulation (T1), 2 weeks after the final stimulation (T2), and 4 weeks after the final stimulation (T3) using the Cambridge Neuropsychological Test Automated Battery (CANTAB).

DISCUSSION: We describe a novel clinical trial to explore whether the administration of tDCS after completing ECT course can accelerates recovery from the CSEs. We hypothesized that the active group would recover faster from the CSEs and be superior to the sham group. If our hypothesis is supported, the use of tDCS could benefit eligible patients who are reluctant to receive ECT and reduce the risk of self-inflicted or suicide due to delays in treatment.

TRIAL REGISTRATION DETAILS: The trial protocol is registered with https://www.chictr.org.cn/ under protocol registration number ChiCTR2300071147 (date of registration: 05.06.2023). Recruitment will start in November 2023.