Abstract
Movement disorders are well recognized as a potential complication of antipsychotic therapy but less well known is its reported presence in antipsychotic naïve psychotic patients without organicity in the prodromal period [1]. Studies in the literature on movement disorders found its prevalence to be 23% in psychotic patients, versus 7% in the non-psychotic population [2].
The conceptualization of schizophrenia as a disorder of cortico-basal ganglia-thalamo-cortical/cerebellar network disconnectivity suggests that the basal ganglia may play a role in its pathogenesis, with mesolimbic dopaminergic hyperactivity as the cause of positive psychotic symptoms [2]. It has been hypothesized that there may be a primary or an adaptive striatal dopaminergic hypoactivity, resulting in negative symptoms and movement disorders [3].
We report a 38-year-old man who developed a movement disorder three months before the onset of positive psychotic symptoms. The movement disorder occurred on the background of a 2-year history of apathy, social withdrawal and functional decline as part of a prodrome. Three weeks before his first psychiatric admission, he experienced visual and auditory hallucinations with accompanying hostility. There was also a noted worsening of his movement disorder with the onset of psychosis.
This patient's movement disorder consisted of spontaneous, involuntary movements of the left upper limb and left facial muscles. They were the result of non-sustained muscular contractions, each lasting less than 3 s and worsened by stress. The limb movements were purposeless, jerky but not choreiform. Facial movements resembled grimacing. There were no tremors or fasciculation. Neurological with cranial nerve examinations were normal.
The patient has no relevant past medical and psychiatric history. There was no history of substance use. His maternal grandfather was diagnosed with Parkinson's disease.
Organic causes of his movement disorder were investigated and excluded. These included Huntington's disease, tic disorders, epilepsy, Wilson's disease, haemochromatosis, autoimmune diseases, vitamin deficiencies, heavy metal poisoning and infections.
After a neurological review, baclofen was empirically trialled for his movement disorder without benefit.
The patient fulfilled the DSM-IV criteria for schizophrenia, and hence olanzapine was prescribed. There was no response after 1 month and his medication was changed to risperidone 6 mg/day. His psychosis improved and his involuntary movements decreased in frequency. He was discharged after a 2-month admission. He remained on risperidone for 4 months post discharge. Due to the persistence of both psychotic symptoms and his movement disorder, risperidone was ceased and quetiapine commenced. His psychotic symptoms worsened on quetiapine and his movement disorder was unchanged. Risperidone was reinstated in the interim with an elective admission planned in the future to initiate clozapine.
On assessment 6 months after discharge, the patient still showed moderate psychiatric illness (Brief Psychiatric Rating Scale: 44). His movement disorder was rated using the Simpson-Angus Scale (score: 3), Abnormal Involuntary Movement Scale (score: 3) and Barnes Akathisia Rating Scale (score: 3). Clozapine was considered in the setting of treatment resistance, negative symptoms and the persistence of his movement disorder [4].
This case highlights how the presence of a movement disorder can be part of a psychotic prodrome and that its persistence with negative symptoms can predict a poorer prognosis and a greater likelihood of treatment resistance [5].
The presence of a movement disorder without organicity in schizophrenia can be an integral part of the illness process, and its poorer prognosis suggests that clinicians should consider clozapine early rather than later [1,5].