Physical Performance and Analgesic Effects of tDCS in Primary Dysmenorrhea

Study Overview
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Brief Summary
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Technological advances and non-invasive techniques to modulate brain function have been developed, including transcranial Direct Current Stimulation (tDCS). Basically, electrodes are placed on the brain regions to stimulate or inhibit it. Subsequently, a continuous electrical current (0.4-2 mA) is imposed, for a period of 3-20 minutes, to modify cortical excitability. Few are the research groups that work on the topic of primary dysmenorrhea and the use of tDCS as the focus of study. Preliminary studies associated the use of tDCS with pain reduction, but the outcomes of physical and behavioral function needs further investigation.

Official Title
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Physical Performance and Analgesic Effects of tDCS in Primary Dysmenorrhea: A Randomized, Double Blind Clinical Trial

Conditions
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Transcranial Direct Current Stimulation, Dysmenorrhea Primary, Pain, Mental Disorders, Physical Fitness

Intervention / Treatment
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* Device: Active Transcranial Direct Current Stimulation
* Device: Sham Transcranial Direct Current Stimulation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: - to have primary dysmenorrhea symptoms for more than 6 months with a mean perception of at least 3 (on a scale of 0 to 10) on the visual analogue scale, to have a regular menstrual cycle from 28 to 32 days. Exclusion Criteria: - Participants will be excluded if they have history of genitourinary disease (infectious oncology or infection), neurogenic bladder dysfunction, to have alcohol or drug abuse in the last 6 months, to have severe depression (score greater than 30 on the Beck depression inventory), to have previously neurological disorders diagnosis and to be pregnant.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 60 Years

Sexes Eligible for Study
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Female

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: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Active-tDCS<br>A constant current (anodic) of 2mA will be applied for 20 minutes over the Primary motor cortex (M1). | Device: Active Transcranial Direct Current Stimulation<br>* For electrode placement, the criteria used by the 10/20 electroencephalography system will be obeyed and the electrodes will be positioned over Primary motor cortex, C3 area for the anode and Fp2 (contralateral supraorbital area) for the cathode electrode. A constant current of 2mA will be applied for 20 minutes.<br>|
| Sham Comparator: Sham-tDCS<br>A constant current (sham) of 2mA will be applied on the Primary motor cortex, but the stimulator will be turned off after 30 seconds . | Device: Sham Transcranial Direct Current Stimulation<br>* For electrode placement, the criteria used by the 10/20 electroencephalography system will be obeyed and the electrodes will be positioned over primary motor cortex, C3 area for the anode and Fp2 (contralateral supraorbital area) for the cathode electrode, but the stimulator will be turned off after 30 seconds of stimulation.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes in pain | Pain diary will be used to assess pain levels | It will be used throughout the first and second menstrual cycle (approximately 60 days). | 
| Changes in pain | Visual Analogue Scale will be used to measure pain levels | First evaluation will be done between the first and third days of initial menstrual cycle. The second evaluation will be done between the first and third days of the next menstrual cycle | 
| Changes in anxiety levels | Hamilton anxiety rating scale will be used to measure anxiety levels | First evaluation will be done between the first and third days of initial menstrual cycle. The second evaluation will be done between the first and third days of the next menstrual cycle | 
| Changes in affectivity | Positive And Negative Affect Scale will be used to measure affectivity | First evaluation will be done between the first and third days of initial menstrual cycle. The second evaluation will be done between the first and third days of the next menstrual cycle | 
| Changes in local pain levels | Digital pressure algometry will be used to measure local pain levels | First evaluation will be done between the first and third days of initial menstrual cycle. The second evaluation will be done between the first and third days of the next menstrual cycle | 
| Changes in hand strength | Hydraulic hand dynamometer will be used to measure hand strength | First evaluation will be done between the first and third days of initial menstrual cycle. The second evaluation will be done between the first and third days of the next menstrual cycle | 
| Changes in functional capacity | Six-minute walk test will be used to measure functional capacity | First evaluation will be done between the first and third days of initial menstrual cycle. The second evaluation will be done between the first and third days of the next menstrual cycle | 
| Changes in flexibility | Thomas test will be used to measure flexibility | First evaluation will be done between the first and third days of initial menstrual cycle. The second evaluation will be done between the first and third days of the next menstrual cycle |