Interactions between transcranial direct current stimulation (tDCS) and pharmacological interventions in the Major Depressive Episode: Findings from a naturalistic study

Background:

Transcranial direct current stimulation (tDCS) is a non-invasive, neuromodulatory technique with an emerging role for treating major depression.

Objective:

To investigate the interactions between tDCS and drug therapy in unipolar and bipolar depressed patients who were refractory for at least one pharmacological treatment.

Methods:

This was a naturalistic study using data from 54 female and 28 male patients (mean age of 54 years) that consecutively visited our psychiatric unit. They received active tDCS (five consecutive days, 2 mA, anodal stimulation over the left and cathodal over the right dorsolateral prefrontal cortex, twice a day, 20 minutes). The outcome variable (mood) was evaluated using the Beck Depression Inventory (BDI) and the Hamilton Depression Rating Scale (HDRS). Predictor variables were age, gender, disorder and pharmacological treatment (seven dummy variables). We performed univariate and multivariate analyses as to identify predictors associated to the outcome.

Results:

After 5 days of treatment, BDI and HDRS scores decreased significantly (29% ± 36%, 18% ± 9%, respectively, P < 0.01 for both). Benzodiazepine use was independently associated with a worse outcome in both univariate (β = 4.92, P < 0.01) and multivariate (β = 5.8, P < 0.01) analyses; whereas use of dual-reuptake inhibitors positively changed tDCS effects in the multivariate model (β = –4.7, P = 0.02). A similar trend was observed for tricyclics (β = –4, P = 0.06) but not for antipsychotics, non-benzodiazepine anticonvulsants and other drugs.

Conclusion:

tDCS over the DLPFC acutely improved depressive symptoms. Besides the inherent limitations of our naturalistic design, our results suggest that tDCS effects might vary according to prior pharmacological treatment, notably benzodiazepines and some antidepressant classes. This issue should be further explored in controlled studies.

Association between baseline serum vascular endothelial growth factor levels and response to electroconvulsive therapy

OBJECTIVE

Several studies have shown that vascular endothelial growth factor (VEGF) is implicated in different neuronal processes involved in major depressive disorder (MDD) and in the mechanisms of action of antidepressants. The aim of this study was to investigate whether VEGF serum levels before treatment might be associated with the antidepressant response.

METHOD

Two groups of patients were enrolled. One was composed of 50 MDD patients receiving an antidepressant drug treatment. Illness severity was measured before the treatment (T0) and after 12 weeks (T1). The second group was composed of 67 treatment-resistant depressed (TRD) patients undergoing electroconvulsive therapy (ECT). Illness severity was assessed before the treatment (T0) and 1 month after the end of ECT (T1). Blood samples for VEGF measurements were collected for both groups at the baseline (T0).

RESULTS

A significant correlation was observed between baseline VEGF serum levels and the percentage reduction in depressive symptomatology after ECT (P = 0.003). In particular, VEGF levels at baseline were significantly lower in patients showing no response to ECT at follow-up (P = 0.008). No correlation between T0 VEGF concentrations and drug treatment outcome was found.

CONCLUSION

Our results suggest that VEGF plays a role in the mechanism of response to ECT.

Transcranial direct current stimulation (TDCS) for severe drug resistent major depression: A ten days treatment protocol

Introduction

Transcranial direct current stimulation (tDCS) is a non-invasive and safe neuromodulation technique that induces prolonged excitability changes of the human cerebral cortex. We have shown that patients with severe major depression treated with tDCS twice a day for 5 days improve by some 30% their depressive symptoms.

Objectives

To optimize the tDCS protocol for the treatment of major depression.

Aims

To assess the therapeutic efficacy in severe drug resistant major depression of tDCS over the dorso-lateral prefrontal cortex (DLPC) twice a day for ten days.

Methods

We studied 15 hospitalized patients aged 37–68 years, with severe major depression. Mood was evaluated using the Beck Depression Inventory (BDI) and Visual Analogue Scales (VAS). tDCS was delivered over the DLPC (anodal electrode was placed on F3 and cathodal electrode on F4) at the intensity of 2mA, for 20 minutes, twice a day for 10 days. Depression scales were administered at baseline and after the last tDCS session on day 10. Drug treatments were maintained unchanged since six weeks before the tDCS study.

Results

After ten days of tDCS the BDI improved by about 40% [(Mean ± SEM) Before: 29.1 ± 3.5; After: 19.4 ± 3.7, p < 0.01]. The feeling of happyness and sadness as evaluated by VAS improved after tDCS (happiness p < 0.01; Sadness p < 0.05).

Conclusions

The improvement reported by patients after ten-days tDCS protocol is greater than that we previously reported after the five-days tDCS protocol. Hence, our preliminary findings suggest that ten-days tDCS protocol should be preferred to the five-days protocol for major depression.

Transcranial direct current stimulation (tDCS) in unipolar vs. bipolar depressive disorder

Transcranial direct current stimulation (tDCS) is a non-invasive method for brain stimulation. Although pilot trials have shown that tDCS yields promising results for major depressive disorder (MDD), its efficacy for bipolar depressive disorder (BDD), a condition with high prevalence and poor treatment outcomes, is unknown. In a previous study we explored the effectiveness of tDCS for MDD. Here, we expanded our research, recruiting patients with MDD and BDD. We enrolled 31 hospitalized patients (24 women) aged 30-70 years 17 with MDD and 14 with BDD (n = 14). All patients received stable drug regimens for at least two weeks before enrollment and drug dosages remained unchanged throughout the study. We applied tDCS over the dorsolateral prefrontal cortex (anodal electrode on the left and cathodal on the right) using a 2 mA-current for 20 min, twice-daily, for 5 consecutive days. Depression was measured at baseline, after 5 tDCS sessions, one week later, and one month after treatment onset. We used the scales of Beck (BDI) and Hamilton-21 items (HDRS). All patients tolerated treatment well without adverse effects. After the fifth tDCS session, depressive symptoms in both study groups diminished, and the beneficial effect persisted at one week and one month. In conclusion, our preliminary study suggests that tDCS is a promising treatment for patients with MDD and BDD.2.

Transcranial direct current stimulation in severe, drug-resistant major depression

BACKGROUND

Though antidepressant drugs are the treatment of choice for severe major depression, a number of patients do not improve with pharmacologic treatment. This study aimed to assess the effects of transcranial direct current stimulation (tDCS) in patients with severe, drug-resistant depression.

METHODS

Fourteen hospitalized patients aged 37-68, with severe major depressive disorder according to DSM-IV.TR criteria, drug resistant, with high risk of suicide and referred for ECT were included. Mood was evaluated using the Beck Depression Inventory (BDI), the Hamilton Depression Rating Scale (HDRS) and the Visual Analogue Scale (VAS). We also administered cognitive tasks to evaluate the possible cognitive effects on memory and attention. tDCS was delivered over the dorsolateral prefrontal cortex (DLPC) (2 mA, 20 min, anode left, cathode right) twice a day.

RESULTS

After five days of treatment although cognitive performances remained unchanged, the BDI and HDRS scores improved more than 30% (BDI p=0.001; HDRS p=0.017). The mood improvement persisted and even increased at four (T2) weeks after treatment ended. The feeling of sadness and mood as evaluated by VAS improved after tDCS (Sadness p=0.007; Mood p=0.036).

CONCLUSIONS

We conclude that frontal tDCS is a simple, promising technique that can be considered in clinical practice as adjuvant treatment for hospitalized patients with severe, drug-resistant major depression.

Intravenous clomipramine decreases excitability of human motor cortex. A study with paired magnetic stimulation

Several recent reports suggest the possibility of monitoring pharmacological effects on brain excitability through transcranial magnetic stimulation (TMS). In these studies, paired magnetic stimulation has been used in normal subjects and on patients who were taking different antiepileptic drugs. The aim of our study was to investigate motor area excitability on depressed patients after intravenous administration of a single dose of clomipramine, a tricyclic antidepressant. Motor cortex excitability was studied by single and paired transcranial magnetic stimulation (TMS) before and after 4, 8 and 24 h from intravenous administration of 25 mg of clomipramine. Cortical excitability was measured using different TMS parameters: motor threshold (MT), motor evoked potential (MEP) amplitude, duration of cortical silent period (CSP), intracortical inhibition (ICI) and intracortical facilitation (ICF). Spinal excitability and peripheral nerve conduction was measured by F response and M wave. A temporary but significant increase of motor threshold and intracortical inhibition and a decrease of intracortical facilitation were observed 4 h following drug administration. MEP amplitude, cortical silent period, F response and M wave were not significantly affected by drug injection. Our findings suggest that a single intravenous dose of clomipramine can exert a significant but transitory suppression of motor cortex excitability in depressed patients. TMS represents a useful research tool in assessing the effects of motor cortical excitability of neuropsychiatric drugs used in psychiatric disease.

[Prevalence of Giardia lamblia, its detection in water and its relationship with environmental factors in Gualeguaychú, Argentina]

The increasing environmental contamination affects the water quality, and is going to raise the waterborne intestinal infections such as giardiosis. This study determined the prevalence of G.lamblia infection in 1201 persons of Gualeguaychú, Argentina. It was observed the relationship between giardiosis and the detection of G.lamblia in the recreational and drinking water and with homes environmental factors. General rate of infection was 19.7%. The group 2-11 years old was the highest (28.0%). No cysts of G.lamblia were found in drinking water, but recreational water was contaminated. Higher rate of infected persons lived in suburban dwellings with dirt floor, latrine, ground-water and close contact with dogs. It is concluded that to drink water is no risk-infection at present, but it will be if this community continues discharging excretsa into the river because this is the source of water for the habitants.