Introduction: Depression is a common mental disorder, and the characteristics of high recurrence, high suicide rate and long incidence cycle make it a "killer" that affects public mental health. Currently, the main treatment is medication, but long-term medication can cause patients to develop drug resistance, relapse soon after discontinuation, and drugs cannot treat cognitive dysfunction in patients with depression, so more effective treatment strategies need to be developed.
With the advancement of medical technology, psychotherapy and physical therapy have shown better treatment effects and provided patients with a variety of treatment options. Recently, the results of a randomized clinical trial of transcranial direct current stimulation to enhance the efficacy of cognitive behavioral therapy in the treatment of depression (Figure 1) were published in The Journal of the American Medical Association (JAMA), which found that transcranial direct current stimulation was effective.
Figure 1 Research results (Source: [1])
The researchers wanted to determine whether Transcranial Direct Current Stimulation (tDCS) could improve the therapeutic effects of Cognitive Behavioral Therapy (CBT). As a result, double-blind, placebo-controlled randomized clinical trials were conducted at six university hospitals in Germany. The population included was adults aged 20 to 65 years with single or recurrent depressive episodes who were either not receiving medication or were receiving stable antidepressants (selective serotonin reuptake inhibitors and/or mirtazapine). The findings were assessed on the Montgomery-Asberg Depression Rating Scale (MADRS), with a score of 0-6 indicating no depression, a score of 7-19 indicating mild depression, a 20-34 indicating moderate depression, and a score of 34 or more indicating severe depression.
A total of 148 patients (89 females, 59 males; mean age 41.1 years; baseline MADRS score of 23.0) were randomized: 53 were assigned to CBT alone (group 0), 48 were assigned to CBT+tDCS (group 1), and 47 were assigned to CBT+pseudo-tDCS (group 2). Participants received a 6-week group intervention that included 12 courses of CBT. Finally, 126 patients (mean age, 41.5 years; baseline MADRS score of 23.0) completed the study. In each intervention group, the intervention was able to reduce the MADRS score by an average of 6.5 points. The Kornd d value is -0.90, indicating a significant effect over time.
Based on changes in MADRS scores, no tDCS+CBT group interventions were found to be superior to CBT+ pseudo-tDCS or CBT alone (Figure 2). However, all patients improved significantly and there were no associated adverse reactions throughout the trial. The combination of CBT and tDCS has been found and confirmed to be safe and feasible, although more research into neuromodulatory mechanisms is needed.
Figure 2 Comparison of clinical trial results (Source: [1])
Multiple previous studies have confirmed the safety and feasibility of tDCS
In fact, before that, there were not a few studies on the safety of tDCS, and a number of previous studies had confirmed that tDCS was safe and feasible. The details are as follows:
● In 2006, Fregni et al. examined the efficacy of tDCS on depression through a randomized, double-blind, pseudo-stimulus controlled trial. In the trial, 10 depressed patients received tDCS acting on the left dorsolateral prefrontal lobe for 5 consecutive days, with an current intensity of 1 mA for 20 minutes per day. The results showed that depressive symptoms in the true stimulation group improved significantly compared with pseudo-stimulation.
●In 2008, Boggio et al. added the occipital lobe stimulation group on this basis, the stimulation intensity increased to 2mA, the stimulation course was extended to 10 days, and the hamilton depression scale and Baker depression scale scores showed that only the prefrontal lobe stimulation group had significant improvement in depressive symptoms.
● In 2008, Boggio et al. evaluated the emotional scale of depressed patients 15 days and 30 days after tDCS stimulation, respectively, and found that the efficacy of tDCS lasted for about 1 month.
● In 2009, Ferrucci changed the frequency of stimulation to 2 times a day, and the results showed significant improvement in depressive symptoms and better efficacy in patients with antimicrobial depression.
● In 2012, Loo et al. explored the effect of stimulation time course on the improvement of symptoms in depressed patients, and 64 depressed patients in the experiment received true/false tDCS on the left dorsolateral prefrontal lobe, and found that only after up to 6 weeks of true stimulation of tDCS had a significant improvement and improvement effect, which to some extent showed that long-term tDCS has a sustained antidepressant effect.
● In 2014, Dell'Osso et al. conducted a special investigation on the efficacy of tDCS during the follow-up period, and found that although the antidepressant effect of tDCS gradually decreased in the treatment time from 1 week to 3 months, the antidepressant effect of tDCS lasted for more than 3 months and there was no side effect in nearly half of the patients.
● In 2015, Talebi et al. also confirmed that the efficacy of tDCS has good temporal stability.
● In 2017, Lefaucheur et al. conducted a secondary evaluation after integrating the results of previous studies, and the results showed that using the tDCS cathode to stimulate the right orbitofrontal cortex was an effective antidepressant therapy.
As an emerging physical therapy, tDCS has received widespread attention because of its convenient use, few side effects and no anesthesia, affordable and other outstanding advantages, but the current study sample size is still relatively small, and the research results are therefore controversial, and in the future, it is necessary to further investigate and verify the antidepressant efficacy of tDCS through large-scale experimental control, multi-center clinical coordination, large sample collection and statistical control analysis.
Written by | Qingyao
Typography | Muzijiu
End
Resources:
[1] Aust S, Brakemeier E, Spies J, et al. Efficacy of Augmentation of Cognitive Behavioral Therapy With Transcranial Direct Current Stimulation for Depression: A Randomized Clinical Trial. JAMA Psychiatry. Published online April 20, 2022. doi:10.1001/jamapsychiatry.2022.0696.
Zhang Lixin, Guo Dongyue, Liu Shuang, Liu Xiaoya, Sheng Yue, Ming Dong. Research progress on transcranial direct current stimulation (tDCS) for the treatment of depression[J].Chinese Journal of Biomedical Engineering,2018,37(05):616-624.
This article is a biological exploration original, welcome to forward and share. If any other media or website needs to be reprinted, the source of biological exploration must be indicated in front of the main text.