Brain Connectivity as a Biomarker of Response to Transcranial Stimulation by Continuous Current in Patients With Stroke

Brain Connectivity as a Biomarker of Response to Transcranial Stimulation by Continuous Current in Patients With Stroke: Sham Controlled, Randomized Clinical Trial

A randomized, double-blind, sham-controlled clinical trial will be conducted with 30 people with stroke, recruited at a referral hospital in João Pessoa. After recruitment they will be randomized into two groups: Group 1 - active stimulation and group - 2 sham stimulation. Participants will receive 10 sessions of ETCC, for 20 minutes, on alternate days (3 times a week), where the electrodes will be positioned over the primary motor cortex. 3 minutes of EEG at rest will be taken from each participant, and they will be instructed not to be actively involved in any cognitive or mental activity. In the first and last meetings, evaluations will be carried out, the outcomes evaluated will be: motor function, quality of life and functional connectivity.

Previous studies analyzed by systematic reviews suggest that the effects of ETCC may vary between subjects, where some stroke patients may not receive any additional benefits from therapy. Thus, it is necessary to use a biomarker that manages to elect those who will possibly benefit from the electric current. Therefore, the objective of this study is to investigate whether the EEG measures of functional connectivity of the target network of the stimulation are associated with the response to ipsilesional anodic ETCC in patients with stroke in the late subacute phase. as well as to observe if these findings can be associated with a clinical improvement of the patient. For that, a randomized, double-blind, sham-controlled clinical trial will be carried out with 30 people with stroke, recruited at a referral hospital in joão Pessoa.

After recruitment they will be randomized into two groups: Group 1 - active stimulation and group - 2 sham stimulation. Participants will receive 10 sessions of ETCC, for 20 minutes, on alternate days (3 times a week), where the electrodes will be positioned over the primary motor cortex. 3 minutes of EEG at rest will be taken from each participant (Eyes open and eyes closed), and they will be instructed not to be actively involved in any cognitive or mental activity. In the first and last meetings, evaluations will be carried out, the outcomes assessed will be: motor function, quality of life and functional connectivity.

Inclusion Criteria:

• Have had a single episode of unilateral, ischemic stroke, in middle cerebral artery proven by means of magnetic resonance imaging or computed tomography;
• Young adult individuals, over 18 years old;
• Both sexes;
• Patients in late subacute stage. Late sub-acute stage will be considered for patients between 3 and 6 months after stroke;
• Mild to moderate patients with a Fugl-Meyer score >85 points;
• Patients with mild to moderate degree of injury severity (NIHHS <17 points);
• Presentation of up to 4 points on the Rankin scale.

Exclusion Criteria:

• Use of drugs that modulate the activity of the Central Nervous System;
• Carriers of implanted metallic or electronic devices; cardiac pacemaker;
• habitual use of drugs or alcohol;
• Epilepsy history report; gestation; people with traumatic brain injury or tumors.