Transcranial Direct Current Stimulation (tDCS) for Depression during Pregnancy: Scientific Evidence and What Is Being Said in the Media-A Systematic Review

Non-Invasive Brain Stimulation Progression in Post-Stroke Depression Treatment: A Systematic Review

Objective

Post-stroke depression (PSD) is the most common psychological disorder in patients with stroke. It not only seriously affects the patient's functional recovery, quality of life, and ability to return to society but also increases stroke recurrence rate and mortality. However, the effectiveness of drug treatment is unpredictable and associated with certain side effects and low compliance. Pharmacological therapy is limited. The field of noninvasive brain stimulation (NIBS) has recently made great progress in developing specific stimulation protocols to alleviate the symptoms of patients with PSD and might offer valid, alternative strategies.

Methods

We systematically searched PubMed, Embase, and the Cochrane Library for investigating the use of NIBS in the treatment of PSD. The methodological quality of selected studies was assessed according to the Risk of Bias 2 (ROB2).

Results

We identified 814 references in 3 databases. After excluding irrelevant and duplicate studies, 14 studies were included. According to the PRISMA checklist, 4 studies were overall comprehensive, 6 had some problems, and 4 had considerable problems with the presented information. The evidence was evaluated using ROB2, with 5 "low-risk" studies, 5 "some concerns" studies, and 4 "high-risk" studies included.

Conclusion

This review provides a comprehensive overview of the clinical trials reported in PSD. Noninvasive brain stimulation is a potentially promising treatment strategy. However, an optimal stimulation protocol needs to be formulated, and much work is required before NIBS can be widely applied in the clinic.

Perinatal Depression and the Role of Synaptic Plasticity in Its Pathogenesis and Treatment

Emerging evidence indicates that synaptic plasticity is significantly involved in the pathophysiology and treatment of perinatal depression. Animal models have demonstrated the effects of overstimulated or weakened synapses in various circuits of the brain in causing affective disturbances. GABAergic theory of depression, stress, and the neuroplasticity model of depression indicate the role of synaptic plasticity in the pathogenesis of depression. Multiple factors related to perinatal depression like hormonal shifts, newer antidepressants, mood stabilizers, monoamine systems, biomarkers, neurotrophins, cytokines, psychotherapy and electroconvulsive therapy have demonstrated direct and indirect effects on synaptic plasticity. In this review, we discuss and summarize the various patho-physiology-related effects of synaptic plasticity in depression. We also discuss the association of treatment-related aspects related to psychotropics, electroconvulsive therapy, neuromodulation, psychotherapy, physical exercise and yoga with synaptic plasticity in perinatal depression. Future insights into newer methods of treatment directed towards the modulation of neuroplasticity for perinatal depression will be discussed.

Fibromyalgia in Pregnancy: Neuro-Endocrine Fluctuations Provide Insight into Pathophysiology and Neuromodulation Treatment

Fibromyalgia (FM) is a chronic pain disorder with unclear pathophysiological mechanisms, which leads to challenges in patient management. In addition to pain, the disorder presents with a broad range of symptoms, such as sleep disruption, chronic fatigue, brain fog, depression, muscle stiffness, and migraine. FM has a considerable female prevalence, and it has been shown that symptoms are influenced by the menstrual cycle and periods of significant hormonal and immunological changes. There is increasing evidence that females with FM experience an aggravation of symptoms in pregnancy, particularly during the third trimester and after childbirth. In this perspective paper, we focus on the neuro-endocrine interactions that occur between progesterone, allopregnanolone, and cortisol during pregnancy, and propose that they align with our previously proposed model of FM pathogenesis based on GABAergic "weakening" in a thalamocortical neural loop system. Based on our hypothesis, we introduce the possibility of utilizing transcranial direct current stimulation (tDCS) as a non-invasive treatment potentially capable of exerting sex-specific effects on FM patients.

Efficacy and Safety of Transcranial Electric Stimulation during the Perinatal Period: A Systematic Literature Review and Three Case Reports

Introduction: The perinatal period is an at-risk period for the emergence or decompensation of psychiatric disorders. Transcranial electrical stimulation (tES) is an effective and safe treatment for many psychiatric disorders. Given the reluctance to use pharmacological treatments during pregnancy or breastfeeding, tES may be an interesting treatment to consider. Our study aims to evaluate the efficacy and safety of tES in the perinatal period through a systematic literature review followed by three original case reports. Method: Following PRISMA guidelines, a systematic review of MEDLINE and ScienceDirect was undertaken to identify studies on tES on women during the perinatal period. The initial research was conducted until 31 December 2021 and search terms included: tDCS, transcranial direct current stimulation, tACS, transcranial alternating current stimulation, tRNS, transcranial random noise stimulation, pregnancy, perinatal, postnatal, and postpartum. Results: Seven studies reporting on 33 women during the perinatal period met the eligibility criteria. No serious adverse effects for the mother or child were reported. Data were limited to the use of tES during pregnancy in patients with schizophrenia or unipolar depression. In addition, we reported three original case reports illustrating the efficacy and safety of tDCS: in a pregnant woman with bipolar depression, in a pregnant woman with post-traumatic stress disorder (sham tDCS), and in a breastfeeding woman with postpartum depression. Conclusions: The results are encouraging, making tES a potentially safe and effective treatment in the perinatal period. Larger studies are needed to confirm these initial results, and any adverse effects on the mother or child should be reported. In addition, research perspectives on the medico-economic benefits of tES, and its realization at home, are to be investigated in the future.

Is transcranial direct current stimulation, alone or in combination with antidepressant medications or psychotherapies, effective in treating major depressive disorder? A systematic review and meta-analysis

BACKGROUND

Transcranial direct current stimulation (tDCS) has shown mixed results for depression treatment. The efficacies of tDCS combination therapies have not been investigated deliberately. This review aims to evaluate the clinical efficacy of tDCS as a monotherapy and in combination with medication, psychotherapy, and ECT for treating adult patients with major depressive disorder (MDD) and identified the factors influencing treatment outcome measures (i.e. depression score, dropout, response, and remission rates).

METHODS

The systematic review was performed in PubMed/Medline, EMBASE, PsycINFO, Web of Sciences, and OpenGrey. Two authors performed independent literature screening and data extraction. The primary outcomes were the standardized mean difference (SMD) for continuous depression scores after treatment and odds ratio (OR) dropout rate; secondary outcomes included ORs for response and remission rates. Random effects models with 95% confidence intervals were employed in all outcomes. The overall effect of tDCS was investigated by meta-analysis. Sources of heterogeneity were explored via subgroup analyses, meta-regression, sensitivity analyses, and assessment of publication bias.

RESULTS

Twelve randomised, sham-controlled trials (active group: N = 251, sham group: N = 204) were included. Overall, the integrated depression score of the active group after treatment was significantly lower than that of the sham group (g = - 0.442, p = 0.017), and further analysis showed that only tDCS + medication achieved a significant lower score (g = - 0.855, p < 0.001). Moreover, this combination achieved a significantly higher response rate than sham intervention (OR = 2.7, p = 0.006), while the response rate remained unchanged for the other three therapies. Dropout and remission rates were similar in the active and sham groups for each therapy and also for the overall intervention. The meta-regression results showed that current intensity is the only predictor for the response rate. None of publication bias was identified.

CONCLUSION

The effect size of tDCS treatment was obviously larger in depression score compared with sham stimulation. The tDCS combined selective serotonin re-uptake inhibitors is the optimized therapy that is effective on depression score and response rate. tDCS monotherapy and combined psychotherapy have no significant effects. The most important parameter for optimization in future trials is treatment strategy.

Transcranial Direct Current Stimulation (tDCS) for Depression during Pregnancy: Results from an Open-Label Pilot Study

INTRODUCTION

Depression is the most common morbidity during pregnancy. Available first-line therapy options are limited and depressive disorders in pregnant women are often untreated, leading to negative effects on maternal and fetal health.

OBJECTIVES

The aim of this open-label pilot study is to extend evidence on the use of transcranial direct current stimulation (tDCS) as a treatment of antenatal depression and to point out options for the use of tDCS in this population.

METHODS

Six drug-free female patients with major depressive disorder during pregnancy (later than 10th gestational week) were included in this pilot study. Patients were treated with twice-daily tDCS (2 mA, 30 min, anode: F3, cathode: F4) over ten days during inpatient stay (Phase 1) and with once-daily tDCS over 10 days during an optional outpatient stay (Phase 2). Clinical (HAMD-21, BDI) and neuropsychological ratings (Trail Making Test A/B) were performed at baseline, after two and four weeks as well as an obstetric examination.

RESULTS

Six right-handed females (23-43 years, 12-33. gestational week) completed Phase 1; four patients additionally joined in Phase 2. tDCS was well tolerated and no adverse effects occurred. Clinical ratings showed an improvement of mean baseline HAMD-21 from 22.50 ± 7.56 to 13.67 ± 3.93 after week 2, and to 8.75 ± 4.99 after week 4. The mean baseline BDI was 26.00 ± 13.90 and declined to 11.17 ± 5.46 after week 2, and to 9.25 ± 3.30 after week 4.

CONCLUSIONS

Statistically significant changes in HAMD-21 and BDI were observed after Phase 1. One patient achieved remission in terms of HAMD in Phase 1. Although this small-scale study lacks sham control, it shows clinical improvement and absence of adverse events in this critical population.

A pilot study on effect of adjunctive transcranial direct current stimulation on symptom domains of depression in patients with depressive disorder

BACKGROUND

Depression is a highly prevalent condition and includes clusters of symptoms, namely, depressive cognition, anxiety, and visceral symptoms. Depressive symptoms often respond sub-optimally to pharmacotherapy. Adjunctive transcranial direct current stimulation (tDCS), a noninvasive brain stimulation modality, may improve depressive symptomatology.

AIM

The aim of this study was to study the effect of tDCS as an augmentation strategy in depression and its various symptom domains.

MATERIALS AND METHODS

It is a prospective interventional study. Patients diagnosed with depressive disorder (based on International Classification of Disease- 10 criteria, diagnosed by treating psychiatrist), aged 18-70 years, who showed inadequate improvement on antidepressant selective serotonin reuptake inhibitors, were recruited after informed consent. Each participant was administered 20 sessions of tDCS over 2 weeks, each session of 20 min, with anode placement at left dorsolateral prefrontal cortex and cathode at right supraorbital region. Hamilton Rating Scale for Depression (HAM-D) was administered pre- and post-intervention to assess the change in symptoms.

RESULTS

Of a total of 35 participants, the mean score on HAM-D prior to and postintervention was 19.97 (standard deviation [SD] = 3.519) and 13.17 (SD = 3.365), respectively. The difference was statistically highly significant (P = 0.000) on paired t-test. All symptom domains of HAM-D, identified using the Cole and Motivala model (Cole et al., 2004), also showed significant reduction from pre-tDCS to post-tDCS scores (P = 0.000).

CONCLUSION

Positive effect of tDCS on depressive symptoms, its tolerability and safety profile, and affordability makes it an effective therapeutic strategy in augmenting antidepressants in patients with depression. However, longer period studies with larger sample size may yield more generalizable results.

"A systematic review of non-invasive neurostimulation for the treatment of depression during pregnancy"

BACKGROUND

Antidepressant use in pregnancy is associated with high levels of decision-making difficulty for patients, and psychotherapy may not be effective for severe symptoms. Alternative treatment options are needed. We conducted a systematic review of the clinical effects and tolerability of non-invasive neurostimulation: repetitive transcranial magnetic stimulation (rTMS), transcranial direct current stimulation (tDCS), transcranial alternating current stimulation (tACS), trigeminal nerve stimulation (TNS), and transcutaneous vagus nerve stimulation (tVNS) for the treatment of antenatal depression.

METHODS

We searched PubMed, Google Scholar and Scopus for published articles in English (1990 to June 2019). Two reviewers reviewed full-text articles, assessed quality, and extracted data on maternal psychiatric, pregnancy and neonatal outcomes.

RESULTS

Of 565 articles, 21 met inclusion criteria: two RCTs (1 rTMS; 1 tDCS), four open-label studies (3 rTMS; 1 tDCS), three case series (3 rTMS), and twelve case reports (9 rTMS; 1 tDCS; 1 tACS; 1 TNS). In all but one published study (1 rTMS), non-invasive neurostimulation resulted in either response or remission of antenatal depression. Minor maternal side effects were reported in rTMS and tDCS studies, but not in other modalities. Fetal adverse effects were not reported in any intervention. A small proportion of participants dropped out of treatment (rTMS, tDCS).

LIMITATIONS

Very few randomized trials have been conducted and there is significant heterogeneity in the parameters of the modalities that have been studied.

CONCLUSIONS

Non-invasive neurostimulation holds promise as a potentially effective and feasible alternative treatment for antenatal depression. Strategies to enhance recruitment of pregnant women into non-invasive neurostimulation trials that have longitudinal follow-up are needed.

Transcranial Direct Current Stimulation for Treatment-Resistant Major Depression: A Double-Blind Randomized Sham-Controlled Trial

In the current study, we tried to evaluate the effect of transcranial direct current stimulation (tDCS) on treatment-resistant major depression. We carried out a double-blind randomized sham-controlled trial was conducted in University Hospitals. Individuals with less than 50% decrease in the intensity of depression after 8 weeks of treatment with selective serotonin reuptake inhibitors were recruited. Thirty patients (16 women) with a mean (SD) age of 47.2 (12.0) years were randomly allocated to 2 groups. For the active group we administered 2-mA stimulation 20 minutes for each session, with 30 seconds ramp-up from 0 and 30 seconds ramp-down. For the sham group we administered 30 seconds ramp-up to 2 mA, 10 seconds stimulation, 30 seconds ramp-down, and 20 minutes no current. The anode was fixed on the center of F3, and the cathode on F4, over the dorsolateral prefrontal cortex. We assessed the Hamilton Depression Rating Scale at the baseline (mean difference = 1.0, P = .630), at the last session of tDCS, and at 1-month postintervention. There were statistically significant differences in the mean Hamilton scores after the intervention, and 1 month later in favor of active group; P < .001, and P = .003, respectively. Mixed analysis of variance showed a significant difference in the mean scores for active group P = .010 and pattern of change during the study P < .001 in favor of active intervention. We concluded that tDCS is an efficient therapy for patients with resistant major depression, and the benefits would remain at least for 1 month.

Transcranial direct current stimulation for Obsessive-Compulsive Disorder: patient selection and perspectives

Transcranial direct current stimulation (tDCS) is a non-invasive neuromodulation technique that has been increasingly examined as an alternative treatment modality for Obsessive-Compulsive Disorder (OCD), due to its low costs, ease of use, and portability. Previous studies have suggested that tDCS may achieve a reasonably good response and present a safe tolerability profile. However, at this point there is not strong evidence for the use of this modality of treatment. Considering that OCD is very heterogeneous with regard to clinical presentation, clinical severity and comorbidities, we have conducted a systematic review of studies on tDCS for OCD aiming to evaluate the clinical characteristics of the selected patients and to discuss perspectives for future studies. A literature search was conducted from inception until March 2019 at PubMed/MedLine and Scielo using the following keywords: "tdcs" or "transcranial direct current stimulation" and "obsessive compulsive disorder". Out of 45 manuscripts, twelve were included. Most of the included studies are uncontrolled. A few controlled studies reported improvement of OCD, but some limitations need to be considered. Our main findings were that the selected patients were adults with severe OCD and psychiatric comorbidities, medicated at the time of assessment and resistant to at least one previous conventional treatment. We could not find any studies including specific populations such as adolescents, elderly, pregnant and breastfeeding participants. Similarly, the potential use of tDCS has not been tested in patients with less severe OCD, as a first treatment option, or for those who do not tolerate pharmacological treatments. These opportunities should be explored in future controlled trials.