Transcranial Direct Current Stimulation (tDCS) as Therapeutical Strategy for Negative Symptoms in Schizophrenia

Study Overview
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Brief Summary
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The current research is aimed at using Transcranial Direct Current Stimulation (tDCS) as complementary therapeutic tool in the treatment of schizophrenia. Patients will be randomized into two groups (tDCS-active x tDCS-sham) accordingly to detailed protocol. Main outcome will be measured by specific clinical rating scales based on the assessment of negative symptoms. A total of 40 patients ought to be enrolled as specified in methodology. Secondary outcomes shall include collateral effects evaluation, anxiety and depressive scales as well as clinical monitoring.

Detailed Description
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Overview The present study is a double-blind randomized clinical trial in which patients should be allocated from a General Psychiatry Service into two groups (tDCS-active x tDCS-sham). Subjects who fulfilled eligibility criteria will undergo ten days of consecutive stimulation (active or sham) and will return after two to four weeks for final clinical assessment. Patients who shown no response in rating scales and that were allocated to sham intervention group will be able to choose whether or not they want to undergo the active intervention at follow up (partial cross-over)

Official Title
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Transcranial Direct Current Stimulation (tDCS) as Therapeutical Strategy for Negative Symptoms in Schizophrenia: a Double-blind Randomized Clinical Trial

Conditions
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Transcranial Direct Current Stimulation, Schizophrenia

Intervention / Treatment
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* Procedure: Transcranial Direct Current Stimulation (tDCS)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: patients with age between 18-59 years diagnostic of Schizophrenia or Schizoaffective Disorder as stated by DSM-IV and confirmed by SCID (Structured Clinical Interview for DSMIV), to be tested by a psychiatrist baseline score higher than 20 for negative symptoms at PAAN patients able to read and understand Portuguese. Exclusion Criteria: other psychiatric diagnosis criteria for bipolar disorder; dementia; other psychotic disturbs; substance related disorders presence of other severe neurological or clinical diseases presence of suicidal behavior (planning or attempt in the previous 4 weeks) pregnancy incapacity of coping with the informed consent specific tDCS limitations (such as anatomic problems) Regarding medication: all patients should have stable dosology of medications for at least 6 weeks

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 59 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: tDCS active<br>Active tDCS as foreseen in research protocol: daily sessions for 10 days with 2mA intensity stimulation during 20 minutes. | Procedure: Transcranial Direct Current Stimulation (tDCS)<br>* Transcranial Direct Current Stimulation. Daily sessions with a total of 10 days intervention. Each intervention will take place with a 2mA intensity during 20 minutes. The current will be delivered by Chattanooga Iontophoresis Dual Channel Delivery Device, that stands for a 2-channels tDCS device in which previous dosage can be set as default to maintain frequently used treatment parameters. Main features include (a) Beeping alerts if electrode fault for open current or high impedance, low battery, treatment completion or power left on; (b)automatic 30 second current ramp up and down during power on/off keeps patient comfortable; (c) Current can be set in 0.1 mA increments between 0.5 mA and 4 mA.<br>|
| Placebo Comparator: tDCS sham<br>Sham tDCS : as foreseen in research protocol: sham stimulation with initial stimulation followed by turning off the device during the same time of intervention as to guarantee blinding | Procedure: Transcranial Direct Current Stimulation (tDCS)<br>* Transcranial Direct Current Stimulation. Daily sessions with a total of 10 days intervention. Each intervention will take place with a 2mA intensity during 20 minutes. The current will be delivered by Chattanooga Iontophoresis Dual Channel Delivery Device, that stands for a 2-channels tDCS device in which previous dosage can be set as default to maintain frequently used treatment parameters. Main features include (a) Beeping alerts if electrode fault for open current or high impedance, low battery, treatment completion or power left on; (b)automatic 30 second current ramp up and down during power on/off keeps patient comfortable; (c) Current can be set in 0.1 mA increments between 0.5 mA and 4 mA.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Negative Symptoms Rates as assessed by the PAANS | Comparison between follow u and baseline PAANS scores with emphasis in negative symptoms scores | Assessment at 0(baseline), 2 weeks and 4 weeks (final outcome) - Positive and Negative Syndrome Scale (PAANS) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Mental Mini Exam | cognitive evaluation as assessed by the Mental Mini Exam | Assessment at 0(baseline), 2 weeks and 4 weeks (final outcome) - Cognitive Screening assessment as performed by the Mental Mini Exam | 
| Moca rating Scale | comparison between follow up and baseline scores in Cognitive evaluation as assessed by MoCa Test | Assessment at 0(baseline), 2 weeks and 4 weeks (final outcome) - Cognitive assessment by MoCa Test | 
| Stroop Victoria | comparison between follow up and baseline scores in atention and inhibitory control as assessed by Stroop Victoria | Assessment at 0(baseline), 2 weeks and 4 weeks (final outcome) - Cognitive assessment by Stroop - Victoria version | 
| Neuropsychological Assessment | comparison between follow up and baseline scores in neuropschological evaluations performed by specialist using SuperLab tool | Assessment at 0(baseline), 2 weeks and 4 weeks (final outcome) - neuropsychologial assessment by trained researcher | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Transcranial Direct Current Stimulation, Schizophrenia