Raphael Boechat-Barros, MD, PhD, Associate Professor, Faculty of Medicine, Professor and Advisor, Postgraduate Program in Medical Sciences, University of Brasília, Professor of the Medicine Course, University Center of the Central Plateau Apparecido dos Santos, Brazil
Although diagnosed schizophrenia can be managed through pharmacologic intervention, side effects of long-term use of these drugs can include tardive dyskinesia (TD), which can be disruptive to a patient’s daily life. Although prescription medications are available for the treatment of TD, alternative therapies are now being considered. For example, treatments for schizophrenia may have the potential for the treatment of TD.
“Indeed, some researchers have already used transcranial Direct Current Stimulation (tDCS) as a treatment for schizophrenia, evaluating effects over its common positive and negative symptoms but not for tardive dyskinesia, and none explored the potential benefits of anodal tDCS over the cerebellum or the primary motor cortex,” write Raphael Boechat-Barros, MD, PhD, and colleagues in Brain Stimulation.
tDCS for Patients With Schizophrenia & TD
To address this unmet need, Dr. Boechat-Barros and his team developed a pilot study that engaged four patients of the psychiatry outpatient clinic of the University Hospital from the University of Brasilia (Brazil) who were diagnosed with chronic schizophrenia and TD. These patients also adhered to a regimen of antipsychotic pharmacologic treatments in accordance with standard practices. All patients gave informed written consent for their participation in the study.
All participants received tDCS treatments consisting of the direct application of a current of 2mA within the course of 20 minutes during a consecutive 5-day period. Gradual and regressive currents were used to produce a fade-in and fade-out effect during the treatment. Patients were described as at rest in a chair during the procedure.
Objective Reduction in Abnormal Movements
These interventions occurred in two phases with a 3-month break between them for washout reasons. During phase I, an anodal electrode was placed over the central cerebellum, and during phase II, the anodal electrode was placed over the supraorbital region.
The documented results were positive, “All patients had an objective reduction in abnormal movements after cerebellar stimulation according to the [Abnormal Involuntary Movement Scale],” wrote Dr. Boechat-Barros and colleagues. “Surprisingly, the improvement was maintained after 3 months washout period and we demonstrated an additional benefit after the M1 stimulation phase. In parallel with TD improvement, we observed improvement in schizophrenia clinical outcomes through CGI-SH, in both stimulation phases.” Video documentation of the four patients is available here.
Whereas side effects of tDCS observed by Dr. Boechat-Barros and colleagues were congruent to similar research, they did note the observance of skin burn at the site of the applied cathode as a mild side effect of tDCS. Despite the small study group, the investigators suggest that the results warrant further study, as tDCS may prove to be a viable treatment option for TD.
