Multicenter Study on the Efficacy of Transcranial Direct Current Stimulation (tDCS) in Post-stroke Motor Recovery

Multicenter Study on the Efficacy of Transcranial Direct Current Stimulation (tDCS) in Post-stroke Motor Recovery

Multicenter Study on the Efficacy of Transcranial Direct Current Stimulation (tDCS) in Post-stroke Motor Recovery

San Gerardo Hospital, Maggiore Bellaria Hospital, Bologna, Azienda Ospedaliero, Universitaria Pisana, Fondazione Don Carlo Gnocchi Onlus, Azienda Ospedaliera Universitaria Integrata Verona, Azienda Unità Sanitaria Locale di Piacenza, Azienda Ospedaliero Universitaria di Cagliari, Ospedale Policlinico San Martino, I.R.C.C.S. Fondazione Santa Lucia, Catholic University of the Sacred Heart, Istituti Clinici Zucchi, Ospedali Riuniti di Foggia

Several previous studies have used tDCS as a neuromodulation tool, showing improvements in several diseases (Lefaucheur et al., 2017). Based on these observations, it is believed that the use of tDCS in combination with specific motor training may provide the opportunity to induce behavioral improvements in patients with motor deficits. As shown in previous reports brain stimulation can, in fact, interact with the intrinsic ability of the brain to "repair" damaged brain functions, increasing the involvement of compensatory functional networks and thus inducing neuroplasticity. If these low-cost, easy-to-use stimulation techniques prove to be useful in improving motor deficits with long-term effects, the current study would open up new and interesting avenues in the field of neurorehabilitation. Given the potential long-lasting effects of tDCS, there is currently a growing interest in the clinical sector with the aim to reduce motor deficits in patients with brain injury. The most widely used protocols in stroke patients include the application of either anodal on the hypsilesional hemisphere or cathodal tDCS on the unaffected hemisphere (contralateral), so as to increase and decrease the excitability of the motor cortex, respectively (Nitsche and Paulus, 2001). The main objective of this study is to evaluate the effectiveness of transcranial direct current stimulation in enhancing the functional recovery of the upper limb of stroke patients after three weeks of neuromotor training and subsequent follow-up. The secondary objective is to evaluate the treatment effects on balance, gait, motor dexterity and disability, besides the functional recovery of the lower limb.

The present study will be conducted in over 15 recruiting centers with a randomized double-blind design. Post-stroke patients will be randomly assigned to 3 parallel groups: Control Group (neuromotor training and sham stimulation), Experimental Group 1 (neuromotor training and cathodal tDCS over the unaffected hemisphere), Group 2 (neuromotor training and anodal tDCS over the affected hemisphere). Participants will be further partitioned on the basis of the acute/subacute and subacute/chronic stages (7-90 and 91 days from lesion onset, respectively).

Both participants and experimenters will be prevented from having knowledge of the assigned stimulation protocol. To do so, the investigator will create a series of numbers paired with real and sham interventions while the outcome assessor will be aware of the patient-number association only.

Anodal tDCS will be performed for 20 minutes over the affected hemisphere with an intensity set to 2 mA

Cathodal tDCS will be performed for 20 minutes over the unaffected hemisphere with an intensity set to 2 mA

Inclusion Criteria: First-ever ischemic stroke Red or white stroke Barthel Index > 90 before lesion onset Exclusion Criteria: Previous inborn neurological disease Previous acquired neurological disease Previous or current major psychiatric illness Epilepsy or anticonvulsant treatment Use of calcium channel blocker drugs Treatments with other technologies (robotics, FES, etc.) Neurolytic treatments with botulinum toxin