Psychiatric and Behavioral Complications of GPi DBS in an Adolescent with Myoclonus Dystonia

Abstract

Myoclonus dystonia is a rare movement disorder that often causes significant disability. Deep brain stimulation of the internal pallidum (GPi DBS) is a recommended treatment for those who do not respond to pharmacotherapy or who have intolerable side effects. This paper reports on the case of a 17-year-old male who was admitted to a tertiary level mental healthcare facility for treatment of psychiatric and behavioral symptoms thought to be related to GPi DBS. Prior to GPi DBS insertion, the patient was diagnosed with anxiety and mild obsessive compulsive disorder (OCD). Following insertion, his OCD became severe and he developed depression, Tourette syndrome, and stuttering. His first admission to a psychiatric unit was for management of a manic episode following treatment for depression with fluoxetine, and he began to exhibit severe aggressive behavior. GPi DBS was turned off, but there were neither changes in dystonic movements nor improvement in aggressive behavior or psychiatric symptoms, though stuttering improved. The patient was transferred to a secure treatment centre where he was able to gain control over his behaviors with intense dialectical behavior therapy, but the aggressive behavior and safety concerns continue to persist today.

The Efficacy and Predictors of Using GPi-DBS to Treat Early-Onset Dystonia: An Individual Patient Analysis

“…For movement symptom severity, GPi-DBS was more effective in DYT-1 (+) and DYT-11 (+) patients compared to DYT-6 (+) patients. Moreover, the change rate of BFMDRS-M between DYT-1 (+) and DYT-11 (+) patients was not significantly different on account of many studies have confirmed that GPi-DBS has significant improvement and certain safety for DYT-1 (+) patients and on DYT-11 (+) syndrome [ 7 , 13 , 26 – 30 ]. Considering the treatment effect is affected by the time after surgery, we set a restriction of 3 years for follow-up time.…”

“…Approximately 25% of DYT-6 (+) patients present with cervical dystonia [ 5 ]. Patients with DYT-11 genotype present with myoclonus, dystonia, or both, but most patients present with myoclonus in childhood or adolescence [ 6 , 7 ]. The patients with DYT-28 (+) are registered as an early-onset generalized dystonia with age at onset of symptoms generally between 4 and 6 years old [ 8 ].…”

Medical management of myoclonus-dystonia and implications for underlying pathophysiology

“…In addition, the motor improvement seen with GPI-DBS appears to be sustained [12] and leads to enhanced quality of life and social adjustment [84]. However, recent studies have raised concern that psychiatric symptoms can worsen following GPi-DBS [85,86].…”

“…Nevertheless, treatment of debilitating psychiatric comorbidities should not be withheld for this reason. Given the potential for psychiatric symptoms to worsen following GPi-DBS to worsen psychiatric symptoms, neuropsychological assessment is important both before and after surgery [85,86].…”

Dissociation in reactive and proactive inhibitory control in Myoclonus dystonia

“…Interestingly, the GPI is a key structure supporting the inhibitory control of actions and deep brain stimulation of the GPI is a gold standard treatment for motor symptoms in MD [29][30][31] . However, despite the motor benefit conferred by deep brain stimulation of the GPI in various dystonic syndromes, discrepant results for psychiatric symptoms have been reported [32][33][34][35][36][37] .…”