Tardive dystonia

Tardive syndrome: An update and mini-review from the perspective of phenomenology

Tardive syndrome (TS) is a group of movement disorders caused by the long-term use of dopamine receptor blocking agents. The phenotypic presentation of TS is diverse, ranging from the most well-characterized symptom of tardive dyskinesia to other symptoms, including dystonia, akathisia, myoclonus, parkinsonism, tremor, and tics. These tardive symptoms are distinct not only in their phenomenology but also in their clinical outcomes. However, our knowledge of the pathophysiology and management of TS is almost exclusively based on tardive dyskinesia. First-generation antipsychotics have a higher risk of inducing TS and have largely been replaced by second-generation antipsychotics with a lower risk of TS. However, patients with off-label use of second-generation antipsychotics are still at risk of developing TS. Thus, the management of TS remains a challenging and important issue for physicians. In this review, we update the information on the epidemiology, phenomenology, and treatment of TS from the perspective of the specific form of TS.

Tardive Dyskinesia After Aripiprazole Treatment That Improved With Tetrabenazine, Clozapine, and Botulinum Toxin

We report on a patient with tardive dyskinesia (TDK) treated with aripiprazole, a third-generation antipsychotic with partial D2 agonist-antagonist activity at both the dopamine and serotonin receptors. The patient’s condition improved with administration of a combination of tetrabenazine, botulinum toxin, and clozapine, which has previously not been used. We suggest that this treatment combination may have potential benefits for patients with TDK. After aripiprazole discontinuation, the patient was treated with clozapine (150 mg/day) and biperiden (8 mg/day). Due to a lack of improvement, we administered 300 units (intramuscularly; IM) of botulinum toxin into the paravertebral muscles every 3 months and 1,000 units IM every 4 months in addition to tetrabenazine (75 mg/day) and biperiden (8 mg/day). The patient stopped this treatment, at which point TDK reappeared. After starting a treatment regimen of clozapine (100 mg/day), tetrabenazine (75 mg/day), and botulinum toxin (300 units IM), the patient’s symptoms remitted.

VMAT2 Inhibitors for Tardive Dyskinesia-Practice Implications

Tardive dyskinesia is a potentially irreversible, debilitating, hyperkinetic movement disorder that can result from dopamine receptor antagonists. Prompt recognition and resolution of symptoms are instrumental in preventing disease irreversibility, though current treatment options have fallen short of robust, effective, and long-term symptom control. In April 2017, the Food and Drug Administration (FDA) approved 2 new vesicular monoamine transporter 2 (VMAT2) inhibitors, deutetrabenazine and valbenazine, for chorea related to Huntington's disease and tardive dyskinesia, respectively. These agents were pharmacologically modified from tetrabenazine, a VMAT2 inhibitor used off-label in the treatment of tardive dyskinesia. Despite FDA-labeled indications of deutetrabenazine and valbenazine, each agent was explored as a treatment option for those with tardive dyskinesia. In this study, the pharmacologic modifications of the 2 new VMAT2 inhibitors are described, with detailed explanation as to how these may impact clinical practice. The associated case series, observational studies, and clinical trials exploring their use in the treatment of tardive dyskinesia are reported with expert opinion on practice implication.

Remission of irreversible aripiprazole-induced tardive dystonia with clozapine: a case report

BACKGROUND

Aripiprazole can cause irreversible tardive dystonia in some individuals, and additional intervention is sometimes needed. Here, we report the first case of aripiprazole-induced irreversible tardive dystonia in which complete recovery of motor function was achieved using the antipsychotic drug clozapine.

CASE PRESENTATION

A 24-year-old man with bipolar disorder was treated with aripiprazole and gradually developed tardive dystonia. Thorough medical and neurological examinations were performed to rule out other possible causes of tardive dystonia. Clozapine was administered when the patient did not improve following long-term withdrawal of aripiprazole or adjuvant medications. Before administration of clozapine, the patient was experiencing severe dystonia as assessed by the Extrapyramidal Symptom Rating Scale. Dystonic symptoms began to improve about 1 month after starting administration of clozapine and were completely resolved 3 months after clozapine administration.

CONCLUSIONS

Clinicians should note the risk of aripiprazole-induced tardive dystonia and consider clozapine as an alternative and effective treatment modality in cases of irreversible tardive dystonia, particularly when concomitant treatment of psychotic symptoms is required.

Challenging neurological symptoms in paediatric palliative care: An approach to symptom evaluation and management in children with neurological impairment

Neurological symptoms are very common in children with life-limiting conditions and are challenging in terms of burden of illness. Moreover, neurological symptoms can significantly impact the child's quality of life and contribute to distress among parents, families, caregivers and health care providers. Knowing how to manage and alleviated these symptoms is essential for providing good palliative care. In the present article, the more common neurological symptoms of agitation/irritability, spasticity and dystonia will be reviewed. The aim of the present brief review is to provide a basic approach to both the identification and treatment of these neurological symptoms. A medication table is provided for quick reference. A brief commentary and guidance for the management of pain are also incorporated, with reference to further literature sources.

Deep brain stimulation suppresses pallidal low frequency activity in patients with phasic dystonic movements

Deep brain stimulation of the globus pallidus internus alleviates involuntary movements in patients with dystonia. However, the mechanism is still not entirely understood. One hypothesis is that deep brain stimulation suppresses abnormally enhanced synchronized oscillatory activity within the motor cortico-basal ganglia network. Here, we explore deep brain stimulation-induced modulation of pathological low frequency (4-12 Hz) pallidal activity that has been described in local field potential recordings in patients with dystonia. Therefore, local field potentials were recorded from 16 hemispheres in 12 patients undergoing deep brain stimulation for severe dystonia using a specially designed amplifier allowing simultaneous high frequency stimulation at therapeutic parameter settings and local field potential recordings. For coherence analysis electroencephalographic activity (EEG) over motor areas and electromyographic activity (EMG) from affected neck muscles were recorded before and immediately after cessation of high frequency stimulation. High frequency stimulation led to a significant reduction of mean power in the 4-12 Hz band by 24.8 ± 7.0% in patients with predominantly phasic dystonia. A significant decrease of coherence between cortical EEG and pallidal local field potential activity in the 4-12 Hz range was revealed for the time period of 30 s after switching off high frequency stimulation. Coherence between EMG activity and pallidal activity was mainly found in patients with phasic dystonic movements where it was suppressed after high frequency stimulation. Our findings suggest that high frequency stimulation may suppress pathologically enhanced low frequency activity in patients with phasic dystonia. These dystonic features are the quickest to respond to high frequency stimulation and may thus directly relate to modulation of pathological basal ganglia activity, whereas improvement in tonic features may depend on long-term plastic changes within the motor network.

Genetic animal models of dystonia: common features and diversities

Animal models are pivotal for studies of pathogenesis and treatment of disorders of the central nervous system which in its complexity cannot yet be modeled in vitro or using computer simulations. The choice of a specific model to test novel therapeutic strategies for a human disease should be based on validity of the model for the approach: does the model reflect symptoms, pathogenesis and treatment response present in human patients? In the movement disorder dystonia, prior to the availability of genetically engineered mice, spontaneous mutants were chosen based on expression of dystonic features, including abnormal muscle contraction, movements and postures. Recent discovery of a number of genes and gene products involved in dystonia initiated research on pathogenesis of the disorder, and the creation of novel models based on gene mutations. Here we present a review of current models of dystonia, with a focus on genetic rodent models, which will likely be first choice in the future either for pathophysiological or for preclinical drug testing or both. In order to help selection of a model depending on expression of a specific feature of dystonia, this review is organized by symptoms and current knowledge of pathogenesis of dystonia. We conclude that albeit there is increasing need for research on pathogenesis of the disease and development of improved models, current models do replicate features of dystonia and are useful tools to develop urgently demanded treatment for this debilitating disorder.

The focal dystonias: current views and challenges for future research

The most common forms of dystonia are those that develop in adults and affect a relatively isolated region of the body. Although these adult-onset focal dystonias are most prevalent, knowledge of their etiologies and pathogenesis has lagged behind some of the rarer generalized dystonias, in which the identification of genetic defects has facilitated both basic and clinical research. This summary provides a brief review of the clinical manifestations of the adult-onset focal dystonias, focusing attention on less well understood clinical manifestations that need further study. It also provides a simple conceptual model for the similarities and differences among the different adult-onset focal dystonias as a rationale for lumping them together as a class of disorders while at the same time splitting them into subtypes. The concluding section outlines some of the most important research questions for the future. Answers to these questions are critical for advancing our understanding of this group of disorders and for developing novel therapeutics.

Alteration of striatal dopaminergic neurotransmission in a mouse model of DYT11 myoclonus-dystonia

Background

DYT11 myoclonus-dystonia (M-D) syndrome is a neurological movement disorder characterized by myoclonic jerks and dystonic postures or movement that can be alleviated by alcohol. It is caused by mutations in SGCE encoding ε-sarcoglycan (ε-SG); the mouse homolog of this gene is Sgce. Paternally-inherited Sgce heterozygous knockout (Sgce KO) mice exhibit myoclonus, motor impairment and anxiety- and depression-like behaviors, modeling several clinical symptoms observed in DYT11 M-D patients. The behavioral deficits are accompanied by abnormally high levels of dopamine and its metabolites in the striatum of Sgce KO mice. Neuroimaging studies of DYT11 M-D patients show reduced dopamine D2 receptor (D2R) availability, although the possibility of increased endogenous dopamine, and consequently, competitive D2R occupancy cannot be ruled out.

Methodology/Principal Findings

The protein levels of striatal D2R, dopamine transporter (DAT), and dopamine D1 receptor (D1R) in Sgce KO mice were analyzed by Western blot. The striatal dopamine release after amphetamine injection in Sgce KO mice were analyzed by microdialysis in vivo. The striatal D2R was significantly decreased in Sgce KO mice without altering DAT and D1R. Sgce KO mice also exhibited a significant increase of dopamine release after amphetamine injection in comparison to wild-type (WT) littermates.

Conclusion/Significance

The results suggest ε-SG may have a role in the regulation of D2R expression. The loss of ε-SG results in decreased striatal D2R, and subsequently leads to increased discharge of dopamine which could contribute to the behavioral impairment observed in DYT11 dystonia patients and in Sgce KO mice. The results suggest that reduction of striatal D2R and enhanced striatal dopamine release may contribute to the pathophysiology of DYT11 M-D patients.

Motor symptoms of schizophrenia: is tardive dyskinesia a symptom or side effect? A modern treatment

Abnormal involuntary dyskinetic movements in schizophrenia patients have been documented for more than 140 years. Clinicians should distinguish between two kinds of disturbances-spontaneous dyskinetic movements and movements induced by psychotropic medications-which may look familiar clinically. As a modern term, tardive dyskinesia (TD) is a potentially permanent neurological hyperkinetic movement disorder that occurs after months or years of taking psychotropic drugs. Several distinct forms of TD exist, specifically tardive akathisia, tardive blepharospasm, tardive dystonia, tardive gait, tardive myoclonus, tardive tremor, and tardive tics, and they have different pathophysiologies and treatment. The pathogenesis of TD remains unclear, and the pathophysiology is complex and multifactorial. Moreover, there is solid evidence of a genetic predisposition to TD. This article summarizes recent relevant publications concerning TD and the most recent studies regarding treatment of this disorder with antioxidative agents.

A biopsychosocial approach to improving quality of life in tardive dystonia

Tardive dystonia is a potential side effect of antipsychotic medications and certain other dopamine antagonists. It is characterized by sustained muscle contractions that lead to abnormal postures and movements. It is generally a permanent side effect that has a significant impact on a patient's physical, psychological, and social well-being, decreasing overall quality of life. The authors present the case of a patient with severe tardive dystonia due to metoclopramide that illustrates the profound physical, psychological, and social impact of this condition. It is important for clinicians to be knowledgeable about tardive dystonia so that they can take active steps to prevent its development and have a positive impact on its prognosis when it does develop by recognizing the condition early. Treatment of tardive dystonia should follow a biopsychosocial approach that combines an array of treatment modalities, depending on the individual presentation. Incorporating a quality of life questionnaire specific to dystonia into clinical practice can help clinicians tailor care to the needs of the individual patient.

Evaluation of akathisia in patients with schizophrenia, schizoaffective disorder, or bipolar I disorder: a post hoc analysis of pooled data from short- and long-term aripiprazole trials

The objective of this article is to assess the clinical characteristics of akathisia in patients with schizophrenia, schizoaffective disorder, or bipolar I disorder receiving aripiprazole, haloperidol, olanzapine, or placebo. We conducted post hoc analyses of pooled safety data from trials in patients with schizophrenia, schizoaffective disorder, and bipolar I disorder. Outcome measures included the incidence of akathisia, time to onset, duration, severity, and discontinuation due to akathisia, concomitant use of benzodiazepines and/or anticholinergics, Barnes Akathisia Rating Scale (BARS) scores, and the correlation between antipsychotic efficacy and akathisia. The results for schizophrenia and schizoaffective disorder were as follows: akathisia in 9% of aripiprazole- and 6% of placebo-treated patients; 12.5% of aripiprazole- versus 24% of haloperidol-treated patients; 11% of aripiprazole- versus 6% of olanzapine-treated patients. Bipolar I disorder: akathisia in 18% of aripiprazole- and 5% of placebo-treated patients. The clinical characteristics of akathisia were similar between each data set, regardless of disease. Akathisia was generally mild-to-moderate in severity. Discontinuation due to akathisia was low in both the schizophrenia trials (aripiprazole 0.3%; placebo 0%; aripiprazole 0.9%; haloperidol 2.3%; aripiprazole 1.2%; olanzapine 0.2%) and the bipolar trials (aripiprazole 2.3%; placebo 0%). Treatment-emergent akathisia was not associated with a poorer clinical response. In conclusion, akathisia with aripiprazole occurred early in treatment, was mild-to-moderate in severity, led to few study discontinuations, and did not compromise therapeutic efficacy.

Drug-Induced Movement Disorders in Older Adults: An Overview for Clinical Practitioners

OBJECTIVE

To provide an overview of some of the most common drug-induced movement disorders (DIMD) seen in the elderly by the primary care clinician. The epidemiology, clinical presentation, differential diagnosis, treatment, risk factors, and preventive measures are presented for each DIMD.

DATA SOURCES

Medical literature and research article search utilizing PubMed (National Library of Medicine), Psych INFO (American Psychological Association), CINAHL Database (CINAHL Information Systems), the Library of Congress Catalogue, and the Internet.

STUDY SELECTION

Reviews and articles from 1954 to 2005 concerning various movement disorders associated with medication in older adults. DATA EXTRACTIONS: Data on movement disorders associated with medications ranging from possible or controversial to well-established.

DATA SYNTHESIS

With the aging of populations in the United States and other countries, the use of medications with potential risk of precipitating movement disorders is increasing. The majority of these iatrogenic problems will be first seen in the geriatric patient in various clinical settings, typically in a primary care setting. To a large extent they will be observed in patients with mild cognitive impairment or dementia having impaired recall and reduced capacity to participate in the diagnostic interview. The challenge to clinicians is complicated by the sizable number of medications that may be involved.

Current treatment of nausea and vomiting associated with gastroparesis: antiemetics, prokinetics, tricyclics

Gastroparesis is a symptomatic chronic disorder characterized by delayed gastric emptying without a mechanical obstruction. Gastroparesis is most often associated with diabetes, gastric surgery, and systemic disorders affecting the neuromuscular control of the stomach. However, no underlying etiology can be found in up to 40% of patients, a condition referred to as idiopathic gastroparesis. Due to the numerous potential etiologies and the highly variable clinical manifestations, the management of gastroparesis is particularly challenging. The purpose of this review is to provide an update on the use of antiemetics, prokinetics, and tricyclics for the treatment for nausea and vomiting associated with gastroparesis.

Ziprasidone-induced tardive laryngeal dystonia: a case report

Tardive laryngeal dystonia, a rare form of dystonic syndrome, was only reported to be induced by typical antipsychotics. Here, we report one case of ziprasidone-induced tardive laryngeal dystonia in a schizophrenic female patient, who showed dysphonia, hoarseness and dyspnea after taking ziprasidone 120 mg/day for 8 months. These symptoms were significantly improved after discontinuing ziprasidone and increasing the dose of trihexyphenidyl for 1 week. Although atypical antipsychotics are associated with a lower risk of extrapyramidal symptoms, caution should be taken for any tardive dystonic movement when using these medications.

Dopamine release is impaired in a mouse model of DYT1 dystonia

Early onset torsion dystonia, the most common form of hereditary primary dystonia, is caused by a mutation in the TOR1A gene, which codes for the protein torsinA. This form of dystonia is referred to as DYT1. We have used a transgenic mouse model of DYT1 dystonia [human mutant-type (hMT)1 mice] to examine the effect of the mutant human torsinA protein on striatal dopaminergic function. Analysis of striatal tissue dopamine (DA) and metabolites using HPLC revealed no difference between hMT1 mice and their non-transgenic littermates. Pre-synaptic DA transporters were studied using in vitro autoradiography with [(3)H]mazindol, a ligand for the membrane DA transporter, and [(3)H]dihydrotetrabenazine, a ligand for the vesicular monoamine transporter. No difference in the density of striatal DA transporter or vesicular monoamine transporter binding sites was observed. Post-synaptic receptors were studied using [(3)H]SCH-23390, a ligand for D(1) class receptors, [(3)H]YM-09151-2 and a ligand for D(2) class receptors. There were again no differences in the density of striatal binding sites for these ligands. Using in vivo microdialysis in awake animals, we studied basal as well as amphetamine-stimulated striatal extracellular DA levels. Basal extracellular DA levels were similar, but the response to amphetamine was markedly attenuated in the hMT1 mice compared with their non-transgenic littermates (253 +/- 71% vs. 561 +/- 132%, p < 0.05, two-way anova). These observations suggest that the mutation in the torsinA protein responsible for DYT1 dystonia may interfere with transport or release of DA, but does not alter pre-synaptic transporters or post-synaptic DA receptors. The defect in DA release as observed may contribute to the abnormalities in motor learning as previously documented in this transgenic mouse model, and may contribute to the clinical symptoms of the human disorder.

The role of dopamine receptors in the neurobehavioral syndrome provoked by activation of L-type calcium channels in rodents

In rodents, activation of L-type calcium channels with +/-BayK 8644 causes an unusual behavioral syndrome that includes dystonia and self-biting. Prior studies have linked both of these behaviors to dysfunction of dopaminergic transmission in the striatum. The current studies were designed to further elucidate the relationship between +/-BayK 8644 and dopaminergic transmission in the expression of the behavioral syndrome. The drug does not appear to release presynaptic dopamine stores, since microdialysis of the striatum revealed dopamine release was unaltered by +/-BayK 8644. In addition, the behaviors were preserved or even exaggerated in mice or rats with virtually complete dopamine depletion. On the other hand, pretreatment of mice with D(3) or D(1/5) dopamine receptor antagonists attenuated the behavioral effects of +/-BayK 8644, while pretreatment with D(2) or D(4) antagonists had no effect. In D(3) receptor knockout mice, +/-BayK 8644 elicited both dystonia and self-biting, but these behaviors were less severe than in matched controls. In D(1) receptor knockout mice, behavioral responses to +/-BayK 8644 appeared exaggerated. These results argue that the behavioral effects of +/-BayK 8644 are not mediated by a presynaptic influence. Instead, the behaviors appear to result from a postsynaptic activation of the drug, which does not require but can be modified by D(3) or D(1/5) receptors.