Transcranial direct current stimulation improves tardive dyskinesia in long-term hospitalized patients with chronic schizophrenia

Objective

This study aimed to evaluate the efficacy and safety of transcranial direct current stimulation (tDCS) in chronic schizophrenia patients with tardive dyskinesia (TD) who were long-term hospitalized.

Methods

Sixty-four inpatients who met the DSM-IV diagnostic criteria for schizophrenia and TD were randomly assigned to either the active (N=35) or sham (N=29) group. Treatment was given 15 times, with each session lasting for 30 min, and an intensity of 2 mA. The anode was placed on the left dorsolateral prefrontal cortex and the cathode on the right supraorbital region. Primary outcome was measured by the changes in Abnormal Involuntary Movements Scale (AIMS) score. Secondary outcomes were measured using the Positive and Negative Syndrome Scale (PANSS) and the Scale for the Assessment of Negative Symptoms (SANS). Adverse effects of tDCS were assessed with an experimenter-administered open-ended questionnaire throughout the experiment.

Results

Of the 64 patients, 52 (81.25%) completed the study. Compared to the sham group, patients in the active group exhibited a significant reduction in both the total AIMS score and the facial-oral subscore (P<0.05). An improvement of at least 30% in total AIMS scores was observed in the active group (14 patients, 50%) compared to the sham group (2 patients, 8.3%) after treatment (P<0.01). There were no between-group differences in the PANSS and SANS total scores. However, there was a significant difference between the two groups in the occurrence of the reported adverse effect of tingling sensation (P<0.05).

Conclusions

TDCS may be an effective and safe treatment for improving the facial-oral motor symptoms of TD in chronically hospitalized patients with schizophrenia.

Significance

This study provides a novel perspective for the clinical treatment of patients with TD.