Treatment of depression with antidepressants is partly effective. Transcranial alternating current stimulation can provide a non-pharmacological alternative for adult patients with major depressive disorder. However, no study has used the stimulation to treat first-episode and drug-naïve patients with major depressive disorder. We used a randomized, double-blind, sham-controlled design to examine the clinical efficacy and safety of the stimulation in treating first-episode drug-naïve patients in a Chinese Han population. From 4 June 2018 to 30 December 2019, 100 patients were recruited and randomly assigned to receive 20 daily 40-min, 77.5 Hz, 15 mA, one forehead and two mastoid sessions of active or sham stimulation (n = 50 for each group) in four consecutive weeks (Week 4), and were followed for additional 4-week efficacy/safety assessment without stimulation (Week 8). The primary outcome was a remission rate defined as the 17-item Hamilton Depression Rating Scale (HDRS-17) score ≤ 7 at Week 8. Secondary analyses were response rates (defined as a reduction of ≥ 50% in the HDRS-17), changes in depressive symptoms and severity from baseline to Week 4 and Week 8, and rates of adverse events. Data were analysed in an intention-to-treat sample. Forty-nine in the active and 46 in the sham completed the study. Twenty-seven of 50 (54%) in the active treatment group and 9 of 50 (18%) in the sham group achieved remission at the end of Week 8. The remission rate was significantly higher in the active group compared to that in the sham group with a risk ratio of 1.78 (95% confidence interval, 1.29, 2.47). Compared with the sham, the active group had a significantly higher remission rate at Week 4, response rates at Weeks 4 and 8, and a larger reduction in depressive symptoms from baseline to Weeks 4 and 8. Adverse events were similar between the groups. In conclusion, the stimulation on the frontal cortex and two mastoids significantly improved symptoms in first-episode drug-naïve patients with major depressive disorder and may be considered as a non-pharmacological intervention for them in an outpatient setting.
Deep brain regions such as hippocampus, insula, and amygdala are involved in neuropsychiatric disorders, including chronic insomnia and depression. Our recent reports showed that transcranial alternating current stimulation (tACS) with a current of 15 mA and a frequency of 77.5 Hz, delivered through a montage of the forehead and both mastoids was safe and effective in intervening chronic insomnia and depression over 8 weeks. However, there is no physical evidence to support whether a large alternating current of 15 mA in tACS can send electrical currents to deep brain tissue in awake humans. Here, we directly recorded local field potentials (LFPs) in the hippocampus, insula and amygdala at different current strengths (1 to 15 mA) in 11 adult patients with drug-resistant epilepsy implanted with stereoelectroencephalography (SEEG) electrodes who received tACS at 77.5 Hz from 1 mA to 15 mA at 77.5 Hz for five minutes at each current for a total of 40 min. For the current of 15 mA at 77.5 Hz, additional 55 min were applied to add up a total of 60 min. Linear regression analysis revealed that the average LFPs for the remaining contacts on both sides of the hippocampus, insula, and amygdala of each patient were statistically associated with the given currents in each patient (p < 0.05–0.01), except for the left insula of one subject (p = 0.053). Alternating currents greater than 7 mA were required to produce significant differences in LFPs in the three brain regions compared to LFPs at 0 mA (p < 0.05). The differences remained significant after adjusting for multiple comparisons (p < 0.05). Our study provides direct evidence that the specific tACS procedures are capable of delivering electrical currents to deep brain tissues, opening a realistic avenue for modulating or treating neuropsychiatric disorders associated with hippocampus, insula, and amygdala.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.