Tardive dyskinesia responsive to deep brain stimulation

A systematic review on the use of clozapine in treatment of tardive dyskinesia and tardive dystonia in patients with psychiatric disorders

RATIONALE

Though clozapine is recommended for treatment of tardive dyskinesia (TD) relating to the use of antipsychotic medications, studies comprehensively investigating the treatment effect of clozapine on TD are still limited.

OBJECTIVES

This review examines the effectiveness of clozapine as an intervention for tardive dyskinesia and dystonia in patients with all psychiatric conditions. Effectiveness of clozapine, duration to exert the effect and dosage used were also analysed.

METHODS

A search in the PubMed, PsycINFO and clinicaltrials databases was performed, using the search terms "Clozapine" AND "dyskinesia" OR "dystonia". Full-text articles that reported the use of clozapine to treat abnormal involuntary movements and were written in English were included.

RESULTS

A total of 48 studies were identified, of which 13 were clinical trials and 35 were case reports. Significant improvement was seen in 86.7% of patients with schizophrenia spectrum disorders (average dose of clozapine = 355 mg/day) and 93% of patients with other psychiatric disorders (average dose of clozapine = 152.5 mg/day). Patients with other psychiatric diagnoses had faster improvement than the patients with schizophrenia spectrum disorders. Variation in improvements and dosage were also seen in the clinical trials.

CONCLUSION

Results suggested an overall effectiveness of clozapine in the treatment of TD for patients with a range of psychiatric conditions. Different response time and clozapine dosage were seen in patients with different psychiatric conditions, suggesting different treatment protocols are required for different conditions. Most of the studies identified are of inadequate qualities, highlighting the need for high quality studies to provide clearer evidence.

Resolution of tardive tremor after bilateral subthalamic nucleus deep brain stimulation placement

Background:

Tardive tremor (TT) is an underrecognized manifestation of tardive syndrome (TS). In our experience, TT is a rather common manifestation of TS, especially in a setting of treatment with aripiprazole, and is a frequent cause of referrals for the evaluation of idiopathic Parkinson disease. There are reports of successful treatment of tardive orofacial dyskinesia and dystonia with deep brain stimulation (DBS) using globus pallidus interna (GPi) as the primary target, but the literature on subthalamic nucleus (STN) DBS for tardive dyskinesia (TD) is lacking. To the best of our knowledge, there are no reports on DBS treatment of TT.

Case Description:

A 75-year-old right-handed female with the medical history of generalized anxiety disorder and major depressive disorder had been treated with thioridazine and citalopram from 1980 till 2010. Around 2008, she developed orolingual dyskinesia. She was started on tetrabenazine in June 2011. She continued to have tremors and developed Parkinsonian gait, both of which worsened overtime. She underwent DBS placement in the left STN in January 2017 with near-complete resolution of her tremors. She underwent right STN implantation in September 2017 with similar improvement in symptoms.

Conclusion:

While DBS-GPi is the preferred treatment in treating oral TD and dystonia, DBS-STN could be considered a safe and effective target in patients with predominating TT and/or tardive Parkinsonism. This patient saw a marked improvement in her symptoms after implantation of DBS electrodes, without significant relapse or recurrence in the years following implantation.