Home-based transcranial direct current stimulation treatment for major depressive disorder: a fully remote phase 2 randomized sham-controlled trial

Innovative approaches in the treatment-resistant depression: exploring different therapeutic pathways

Treatment-resistant depression (TRD) remains a vital challenge in psychiatry, affecting a significant number of patients with major depressive disorder. Current pharmacological approaches often do not provide sufficient therapeutic results, prompting the need for innovative treatments. This review summarizes recent advances in TRD management, including non-pharmacological therapies such as transcranial magnetic stimulation, deep brain stimulation, electroconvulsive therapy, and vagus nerve stimulation, and describes their mechanisms of action. Novel pharmacotherapies, particularly glutamatergic modulators like ketamine and esketamine, have shown promising results with esketamine being available to eligible patients in Poland since 2023 within a drug program. Electroconvulsive therapy remains an effective treatment for TRD, usually with small side effects mainly including transient memory impairment, headache, or cardiovascular changes. Transcranial magnetic stimulation is a non-invasive procedure with proven efficacy; therefore several psychiatric organizations recommend it as a treatment option for major depressive disorder in their clinical guidelines. Deep brain stimulation is a relatively new treatment modality for TRD, with its primary risk being associated with the required neurosurgical procedure. Vagus nerve stimulation seems to be a promising adjunctive treatment for TRD, showing significant improvements in depressive symptoms, especially at higher electrical doses but with no side effects. While these treatments appear to have potential, personalized approaches are crucial for optimizing outcomes. Future research should focus on refining the techniques, improving safety profiles, and validating the long-term efficacy.

Effect of home-based transcranial direct current stimulation (tDCS) on cognitive functioning in bipolar depression: an open-label, single-arm acceptability and feasibility study

Bipolar depression is commonly accompanied by cognitive impairments. Transcranial direct current stimulation (tDCS) is emerging as a novel non-invasive treatment for bipolar depression. Given the portability and safety of tDCS, we developed a home-based protocol with real-time supervision. Our aim was to assess the cognitive effects of a course of tDCS treatment in bipolar depression. 44 participants (31 women, mean age 47.27 years, SD 12.89) with bipolar depression of at least a moderate severity received 21 sessions of home-based tDCS over 6 weeks in an open-label design. The stimulation protocol involved 2 mA in a bilateral frontal montage (F3 anode, F4 cathode) for 30 min per session. Cognitive assessments were conducted at baseline and after the course of treatment: Rey Auditory Verbal Learning Test (RAVLT) to assess verbal learning and memory and Symbol Digit Modalities Test (SDMT) to assess psychomotor processing speed and visuospatial attention. 93.18% (n = 41) completed RAVLT and 59.09% of participants (n = 26) completed SDMT. A significant improvement was observed in RAVLT verbal learning score post-treatment (p = 0.002), which was not maintained following adjustment for improvement in depressive symptoms. In summary, a course of home-based tDCS in bipolar depression was associated with an improvement in verbal learning, which appeared to be related to improvement in depressive symptoms. These findings suggest potential benefits of tDCS for addressing cognitive impairments in bipolar depression, which can be investigated further in a sham-controlled design.

Astrocytic pleiotrophin deficiency in the prefrontal cortex contributes to stress-induced depressive-like responses in male mice

Astrocytes are closely linked to depression, and the prefrontal cortex (PFC) is an important brain region involved in major depressive disorder (MDD). However, the underlying mechanism by which astrocytes within PFC contribute to MDD remains unclear. Using single-nucleus RNA sequencing analyses, we show a significant reduction in astrocytes and attenuated pleiotrophin-protein tyrosine phosphatase receptor type Z1 (PTN-PTPRZ1) signaling in astrocyte-to-excitatory neuron communication in the PFC of male MDD patients. We find reduced astrocytes and PTN in the dorsomedial PFC of male mice with depression induced by chronic restraint and social defeat stress. Knockdown of astrocytic PTN induces depression-related responses, which is reversed by exogenous PTN supplementation or overexpression of astrocytic PTN. The antidepressant effects exerted by astrocytic PTN require interaction with PTPRZ1 in excitatory neurons, and PTN-PTPRZ1 activates the AKT signaling pathway to regulate depression-related responses. Our findings indicate the PTN-PTPRZ1-AKT pathway may be a potential therapeutic target for MDD.

Virtual Reality and Relaxation for the Treatment of Generalized Anxiety Disorder: A Randomized Comparative Study with Standard Intervention

Background/Objectives: Modern therapeutic strategies incorporating virtual reality (VR) have emerged as potential treatments for generalized anxiety disorder (GAD), a prevalent and debilitating condition that is challenging to cure. This study aimed to evaluate the efficacy of VR combined with relaxation techniques in patients with GAD by comparing VR-based relaxation with standard mental imagery (MI) relaxation. Methods: Fifty-eight patients with GAD participated in a randomized comparative trial. Specific virtual environments were created using an inexpensive game engine/level editor (GLE). Psychometric scales and physiological instruments were employed to assess the effects of relaxation therapy on anxiety, depression, quality of life, presence within virtual environments and cybersickness. Results: Both the VR and MI groups demonstrated statistically significant improvements in anxiety, worry and mental quality of life scores. However, no significant differences were observed between the two groups in pre-post comparisons of psychometric scores. The VR group exhibited a noticeably higher protocol completion rate and a significant increase in heart rate variability during the therapy. The level of presence in the VR group was satisfactory and significantly correlated with physiological improvements and anxiety reduction, while cybersickness remained low. Participants' preferences for specific virtual environments for relaxation are also discussed. Conclusions: These findings suggest that teaching and practicing relaxation in VR holds therapeutic potential for the treatment of GAD. Further research leveraging advanced VR sensory equipment and artificial intelligence agents is warranted to enhance therapeutic outcomes and explore additional applications.

Efficacy and safety of home-based transcranial direct current stimulation as adjunct treatment for cognitive improvement in major depressive disorder: A double-blind, randomized, multi-site clinical trial

BACKGROUND

Transcranial direct current stimulation (tDCS) is a promising treatment for major depressive disorder (MDD). This study evaluated its antidepressant and cognitive effects as a safe, effective, home-based therapy for MDD.

METHODS

This double-blind, sham-controlled, randomized trial divided participants into low-intensity (1 mA, n = 47), high-intensity (2 mA, n = 49), and sham (n = 45) groups, receiving 42 daily tDCS sessions, including weekends and holidays, targeting the dorsolateral prefrontal cortex for 30 minutes. Assessments were conducted at baseline and weeks 2, 4, and 6. The primary outcome was cognitive improvement assessed by changes in total accuracy on the 2-back test from baseline to week 6. Secondary outcomes included changes in depressive symptoms (HAM-D), anxiety (HAM-A), and quality of life (QLES). Adverse events were monitored. This trial was registered with ClinicalTrials.gov (NCT04709952).

RESULTS

In the tDCS study, of 141 participants (102 [72.3%] women; mean age 35.7 years, standard deviation 12.7), 95 completed the trial. Mean changes in the total accuracy scores from baseline to week 6 were compared across the three groups using an F-test. Linear mixed-effects models examined the interaction of group and time. Results showed no significant differences among groups in cognitive or depressive outcomes at week 6. Active groups experienced more mild adverse events compared to sham but had similar rates of severe adverse events and dropout.

CONCLUSIONS

Home-based tDCS for MDD demonstrated no evidence of effectiveness but was safe and well-tolerated. Further research is needed to address the technical limitations, evaluate broader cognitive functions, and extend durations to evaluate its therapeutic potential.

Novel NIBS in psychiatry: Unveiling TUS and TI for research and treatment

Mental disorders pose a significant global burden and constitute a major cause of disability worldwide. Despite strides in treatment, a substantial number of patients do not respond adequately, underscoring the urgency for innovative approaches. Traditional non-invasive brain stimulation techniques show promise, yet grapple with challenges regarding efficacy and specificity. Variations in mechanistic understanding and reliability among non-invasive brain stimulation methods are common, with limited spatial precision and physical constraints hindering the ability to target subcortical areas often implicated in the disease aetiology. Novel techniques such as transcranial ultrasonic stimulation and temporal interference stimulation have gained notable momentum in recent years, possibly addressing these shortcomings. Transcranial ultrasonic stimulation (TUS) offers exceptional spatial precision and deeper penetration compared with conventional electrical and magnetic stimulation techniques. Studies targeting a diverse array of brain regions have shown its potential to affect neuronal excitability, functional connectivity and symptoms of psychiatric disorders such as major depressive disorder. Nevertheless, challenges such as target planning and addressing acoustic interactions with the skull must be tackled for its widespread adoption in research and potentially clinical settings. Similar to transcranial ultrasonic stimulation, temporal interference (TI) stimulation offers the potential to target deeper subcortical areas compared with traditional non-invasive brain stimulation, albeit requiring a comparatively higher current for equivalent neural effects. Promising yet still sparse research highlights TI's potential to selectively modulate neuronal activity, showing potential for its utility in psychiatry. Overall, recent strides in non-invasive brain stimulation methods like transcranial ultrasonic stimulation and temporal interference stimulation not only open new research avenues but also hold potential as effective treatments in psychiatry. However, realising their full potential necessitates addressing practical challenges and optimising their application effectively.

Effect of home-based transcranial direct current stimulation (tDCS) on cognitive functioning in bipolar depression

Bipolar depression is commonly accompanied by cognitive impairments. Transcranial direct current stimulation (tDCS) is emerging as a novel non-invasive treatment for bipolar depression. Given the portability and safety of tDCS, we developed a home-based protocol with real-time supervision. Our aim was to assess the cognitive effects of tDCS in bipolar disorder. 44 participants (31 women, mean age 47.27 ± 12.89 years) experiencing a moderate to severe depressive episode received 21 sessions of home-based tDCS over 6 weeks. The stimulation protocol involved 2 mA in a bilateral frontal montage (F3 anode, F4 cathode) for 30 minutes per session. The cognitive assessments were conducted at baseline and after the course of treatment. Rey Auditory Verbal Learning Test (RAVLT) was used to assess verbal learning and memory and the Symbol Digit Modalities Test (SDMT) to assess psychomotor processing speed and visuospatial attention. 93.18% (n=41) completed RAVLT and 59.09% of participants (n=26) completed SDMT. A significant improvement was observed in the RAVLT short-term verbal memory score post-treatment (p = 0.002). Improvements were observed in RAVLT verbal learning, RAVLT post-interference recall, and SDMT, which were not statistically significant. In summary, cognitive performance showed an improvement in bipolar depression following treatment with home-based tDCS, suggesting it can be an effective intervention for cognitive deficits in bipolar depression and positively impact cognitive function.