The current status of tardive dystonia

An Evidence-Based Update on Anticholinergic Use for Drug-Induced Movement Disorders

Drug-induced movement disorders (DIMDs) are associated with use of dopamine receptor blocking agents (DRBAs), including antipsychotics. The most common forms are drug-induced parkinsonism (DIP), dystonia, akathisia, and tardive dyskinesia (TD). Although rare, neuroleptic malignant syndrome (NMS) is a potentially life-threatening consequence of DRBA exposure. Recommendations for anticholinergic use in patients with DIMDs were developed on the basis of a roundtable discussion with healthcare professionals with extensive expertise in DIMD management, along with a comprehensive literature review. The roundtable agreed that "extrapyramidal symptoms" is a non-specific term that encompasses a range of abnormal movements. As such, it contributes to a misconception that all DIMDs can be treated in the same way, potentially leading to the misuse and overprescribing of anticholinergics. DIMDs are neurobiologically and clinically distinct, with different treatment paradigms and varying levels of evidence for anticholinergic use. Whereas evidence indicates anticholinergics can be effective for DIP and dystonia, they are not recommended for TD, akathisia, or NMS; nor are they supported for preventing DIMDs except in individuals at high risk for acute dystonia. Anticholinergics may induce serious peripheral adverse effects (e.g., urinary retention) and central effects (e.g., impaired cognition), all of which can be highly concerning especially in older adults. Appropriate use of anticholinergics therefore requires careful consideration of the evidence for efficacy (e.g., supportive for DIP but not TD) and the risks for serious adverse events. If used, anticholinergic medications should be prescribed at the lowest effective dose and for limited periods of time. When discontinued, they should be tapered gradually.

Reversible Dysphagia Associated With Risperidone Presenting With a Choking Episode

Dysphagia has been associated with antipsychotic drug use. This case report describes the management of dysphagia in a psychiatric patient who presented to the emergency department from a psychiatric facility after choking on a hot dog. The patient was on risperidone 4 mg, initiated a month prior to treat acute psychosis. Foreign body removal from the distal trachea was performed by bronchoscopy, followed by a swallow evaluation by the speech and swallow team. The patient exhibited severe oropharyngeal dysphagia, leading to aspiration pneumonia and subsequent enteral feeding through a nasojejunal tube. Changes in medication from risperidone to aripiprazole, along with a short course of benztropine and dietary modifications, were implemented, with gradual improvement in swallowing function observed during the hospital stay. The patient's complex medical and psychiatric history contributed to a prolonged hospital stay.

Mealtime difficulties in adults with mental health conditions: an integrative review

BACKGROUND

Dysphagia and choking are highly prevalent in adults with mental health conditions. However, there is scant research considering the personal experience of dysphagia for this population.

AIMS

To understand the evidence-base for strategies to involve the patient in recognition, assessment and treatment of mealtime difficulties.

METHODS

This integrative review synthesised the literature on the experience of dysphagia in patients with mental health conditions. Patient consultation led to co-designed search terms and eligibility criteria for a systematic search of five scientific databases following Prisma guidance. Quality assessment of the eligible studies and reflexive thematic analysis were completed.

RESULTS

31 studies were included for review. These included case reports, literature reviews and cross-sectional studies. Quality of evidence was weak and no intervention studies were identified. There was scant detail regarding the personal experience of dysphagia or choking. Themes identified related to biomedical perspectives, influencing factors presented without context, and decision-making led by clinicians.

CONCLUSIONS

Guidance on mental healthcare calls attention to under-diagnosis of physical co-morbidities and advocates patient inclusion. However, the patient voice in this population is rarely described regarding dysphagia. Further inclusive research is indicated to explore the impact of dysphagia and choking, and implications for interventions and outcome measures.

Late-Onset Dystonia With Low-Dose Olanzapine in an Older Person: A Case Report

Drug-induced dystonias are rare but can occur with second-generation antipsychotics. They are usually dose-related and occur soon after dose initiation. This case describes the development of dystonia after two years of olanzapine 5 mg daily in an older person with Alzheimer's dementia. The dystonia resolved after diphenhydramine treatment on day two of hospitalization, but then the patient became delirious, which was treated with lorazepam on day three. Six days after admission, she developed tremors and rigidity that self-resolved. Her dystonia resolved after 11 days. The recurrence of symptoms during the hospitalization may have been a result of the progression of her dementia. This is the first known case of a patient developing dystonia after chronic use of low-dose olanzapine. This was not characterized as tardive dystonia because the dystonia was resolved with anticholinergic medication. This case illustrates the difficulty of using anticholinergics to treat dystonias in older people, which can precipitate delirium. Choosing an alternative antipsychotic with less extrapyramidal symptom risk is challenging as she had previous trials with quetiapine and risperidone. Clozapine was deemed an unfavorable alternative, as laboratory monitoring would be burdensome. Olanzapine-induced dystonias can develop anytime during therapy. Families must balance the desire for mood stabilization with antipsychotics side effects.

Genetic association study detected misalignment in previous whole exome sequence: association study of ZNF806 and SART3 in tardive dystonia

Tardive dystonia is one of the most serious types of extrapyramidal symptoms that antipsychotics can cause. There is no established treatment to relieve this symptom, and its etiology is unclear. Recently, we identified very rare single-nucleotide polymorphisms (SNPs) on ZNF806 and SART3 by exome sequencing in three patients with profoundly severe tardive dystonia. Here, we conducted an association study (case, N = 16 vs. control, N = 96) on the rarest SNP selected from each gene. The results showed that rs2287546 on SART3 was not related to tardive dystonia and that rs4953961 on ZNF806 was a heterozygote in all the subjects, implying the absence of a rare SNP in this locus. We found three other genomic regions with high similarity to the relevant region on ZNF806 by BLAT searches. This strongly suggested a misalignment error in this region in our previous exome sequence. In conclusion, ZNF806 and SART3 are unlikely to be related to tardive dystonia.

Globus Pallidus Internus Deep Brain Stimulation for Dystonic Opisthotonus in Adult-Onset Dystonia: A Personalized Approach

Introduction

Dystonic opisthotonus is defined as a backward arching of the neck and trunk, which ranges in severity from mild backward jerks to life-threatening prolonged severe muscular spasms. It can be associated with generalized dystonic syndromes or, rarely, present as a form of axial truncal dystonia. The etiologies vary from idiopathic, genetic, tardive, hereditary-degenerative, or associated with parkinsonism. We report clinical cases of dystonic opisthotonus associated with adult-onset dystonic syndromes, that benefitted from globus pallidus internus (GPi) deep brain stimulation (DBS).

Methods

Clinical data from patients with dystonic syndromes who underwent comprehensive medical review, multidisciplinary assessment, and tailored medical and neurosurgical managements were prospectively analyzed. Quantification of dystonia severity pre- and postoperatively was performed using the Burke-Fahn-Marsden Dystonia Rating Scale and quantification of overall pain severity was performed using the Visual Analog Scale.

Results

Three male patients, with age of onset of the dystonic symptoms ranging from 32 to 51 years old, were included. Tardive dystonia, adult-onset dystonia-parkinsonism and adult-onset idiopathic axial dystonia were the etiologies identified. Clinical investigation and management were tailored according to the complexity of the individual presentations. Although they shared common clinical features of adult-onset dystonia, disabling dystonic opisthotonus, refractory to medical management, was the main indication for GPi-DBS in all patients presented. The severity of axial dystonia ranged from disturbance of daily function to life-threatening truncal distortion. All three patients underwent bilateral GPi DBS at a mean age of 52 years (range 48–55 years), after mean duration of symptoms prior to DBS of 10.7 years (range 4–16 years). All patients showed a rapid and sustained clinical improvement of their symptoms, notably of the dystonic opisthotonos, at postoperative follow-up ranging from 20 to 175 months. In some, the ability to resume activities of daily living and reintegration into the society was remarkable.

Conclusion

Adult-onset dystonic syndromes predominantly presenting with dystonic opisthotonus are relatively rare. The specific nature of dystonic opisthotonus remains a treatment challenge, and thorough investigation of this highly disabling condition with varying etiologies is often necessary. Although patients may be refractory to medical management and botulinum toxin injection, Globus pallidus stimulation timed and tailored provided symptomatic control in this cohort and may be considered in other carefully selected cases.

Long-Term Follow-Up of 12 Patients Treated with Bilateral Pallidal Stimulation for Tardive Dystonia

Tardive dystonia (TD) is a side effect of prolonged dopamine receptor antagonist intake. TD can be a chronic disabling movement disorder despite medical treatment. We previously demonstrated successful outcomes in six patients with TD using deep brain stimulation (DBS); however, more patients are needed to better understand the efficacy of DBS for treating TD. We assessed the outcomes of 12 patients with TD who underwent globus pallidus internus (GPi) DBS by extending the follow-up period of previously reported patients and enrolling six additional patients. All patients were refractory to pharmacotherapy and were referred for surgical intervention by movement disorder neurologists. In all patients, DBS electrodes were implanted bilaterally within the GPi under general anesthesia. The mean ages at TD onset and surgery were 39.2 ± 12.3 years and 44.6 ± 12.3 years, respectively. The Burke–Fahn–Marsden Dystonia Rating Scale (BFMDRS) performed the preoperative and postoperative evaluations. The average BFMDRS improvement rate at 1 month postoperatively was 75.6 ± 27.6% (p < 0.001). Ten patients were assessed in the long term (78.0 ± 50.4 months after surgery), and the long-term BFMDRS improvement was 78.0 ± 20.4%. Two patients responded poorly to DBS. Both had a longer duration from TD onset to surgery and older age at surgery. A cognitive and psychiatric decline was observed in the oldest patients, while no such decline ware observed in the younger patients. In most patients with TD, GPi-DBS could be a beneficial therapeutic option for long-term relief of TD.

Neurobiological mechanisms associated with antipsychotic drug-induced dystonia

Dystonia is by far the most intrusive and invalidating extrapyramidal side effect of potent classical antipsychotic drugs. Antipsychotic drug-induced dystonia is classified in both acute and tardive forms. The incidence of drug-induced dystonia is associated with the affinity to inhibitory dopamine D2 receptors. Particularly acute dystonia can be treated with anticholinergic drugs, but the tardive form may also respond to such antimuscarinic treatment, which contrasts their effects in tardive dyskinesia. Combining knowledge of the pathophysiology of primary focal dystonia with the anatomical and pharmacological organization of the extrapyramidal system may shed some light on the mechanism of antipsychotic drug-induced dystonia. A suitable hypothesis is derived from the understanding that focal dystonia may be due to a faulty processing of somatosensory input, so leading to inappropriate execution of well-trained motor programmes. Neuroplastic alterations of the sensitivity of extrapyramidal medium-sized spiny projection neurons to stimulation, which are induced by the training of specific complex movements, lead to the sophisticated execution of these motor plans. The sudden and non-selective disinhibition of indirect pathway medium-sized spiny projection neurons by blocking dopamine D2 receptors may distort this process. Shutting down the widespread influence of tonically active giant cholinergic interneurons on all medium-sized spiny projection neurons by blocking muscarinic receptors may result in a reduction of the influence of extrapyramidal cortical-striatal-thalamic-cortical regulation. Furthermore, striatal cholinergic interneurons have an important role to play in integrating cerebellar input with the output of cerebral cortex, and are also targeted by dopaminergic nigrostriatal fibres affecting dopamine D2 receptors.

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 update: the syndrome

Tardive dyskinesia is a common iatrogenic neurological and neurobehavioural syndrome associated with the use of antidopaminergic medication, especially antipsychotics. Prior to the introduction of the newer antipsychotics in the 1990s, it was one of the major areas of psychiatric research but interest waned as the new drugs were reputed to have a reduced liability to extrapyramidal adverse effects in general, a claim now discredited by numerous pragmatic research studies. Early small-scale short-term prevalence studies were presented as evidence to support the assumption that patients on the newer drugs did indeed have a lower prevalence of tardive dyskinesia but recent large-scale review of studies with patients exposed for longer suggest that things have not changed. This article presents a clinical overview of a complex and varied syndrome in terms of its phenomenology, epidemiology and risk factors; a companion article will consider treatment. This overview aims to highlight tardive dyskinesia once again, especially to practitioners who have trained in an environment where this was considered mainly in historical terms.

LEARNING OBJECTIVES

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DECLARATION OF INTEREST

None.

Surgical treatment of dystonia

INTRODUCTION

Treatment of dystonia should be individualized and tailored to the specific needs of patients. Surgical treatment is an important option in medically refractory cases. Several issues regarding type of the surgical intervention, targets, and predict factors of benefit are still under debate. Areas covered: To date, several clinical trials have proven the benefit and safety of deep brain stimulation (DBS) for inherited and idiopathic isolated dystonia, whereas there is still insufficient evidence in combined and acquired dystonia. The globus pallidus internus (GPi) is the target with the best evidence, but data on the subthalamic nucleus seems also to be promising. Evidence suggests that younger patients with shorter disease duration experience greater benefit following DBS. Pallidotomy and thalamotomy are currently used in subset of carefully selected patients. The development of MRI-guided focused ultrasound might bring new options to ablation approach in dystonia. Expert commentary: GPi-DBS is effective and safe in isolated dystonia and should not be delayed when symptoms compromise quality of life and functionality. Identifying the best candidates to surgery on acquired and combined dystonias is still necessary. New insights about pathophysiology of dystonia and new technological advances will undoubtedly help to tailor surgery and optimize clinical effects.

Antipsychotic-Induced Pisa Syndrome: A 2-Year Follow-up Study

OBJECTIVES

Pisa syndrome is characterized by lateral trunk flexion. It is an uncommon adverse drug reaction in patients on antipsychotic medication. Although Pisa syndrome has been reported in patients on antipsychotic treatment, previous studies have not discussed the prognosis of patients with Pisa syndrome. We studied psychiatric patients with Pisa syndrome following antipsychotic treatment for a 2-year period.

METHODS

From January 2012 to December 2014, 13 inpatients with Pisa syndrome following antipsychotic treatment were identified at our institution, from a prospectively collected database. These patients were studied for a 2-year period.

RESULTS

The prevalence rate of Pisa syndrome during neuroleptic treatment was 0.45% in men and 0.37% in women, with a collective prevalence rate of 0.42%. The mean age of patients with Pisa syndrome was 47 years. Eight (61.5%) of the cases had a position with a tilt toward the right side. In 5 (38.5%) of the cases, a tilt toward the left side was observed. The average Cobb angle of the trunk was 17.3 (SD, 4.0) degrees. On presentation with Pisa syndrome within 3 months of medication modification, the pattern of trunk dystonia had a significantly shorter duration (P = .024) compared with that seen in the tardive-onset group.

CONCLUSIONS

Pisa syndrome is an uncommon adverse event that can also be chronic or recurrent, especially in those with tardive onset. We should be aware of the risks in patients with the following predisposing factors: old age, chronic psychosis, long-term antipsychotic use, advanced drug-induced parkinsonism, and combined pharmacologic treatment.

Deep Brain Stimulation for the Dystonias: Evidence, Knowledge Gaps, and Practical Considerations

BACKGROUND

Deep brain stimulation (DBS) of the globus pallidus internus (GPi-DBS) is among the most effective treatment options for dystonias. Because the term "dystonia" is defined by a characteristic phenomenology of involuntary muscle contractions, which may present with a large clinical and pathogenetic heterogeneity, decision making for or against GPi-DBS can be difficult in individual patients.

METHODS

A search of the PubMed database for research and review articles, focused on "deep brain stimulation" and "dystonia" was used to identify clinical trials and to determine current concepts in the surgical management of dystonia. Patient selection in previous studies was recategorized by the authors using the new dystonia classification put forward by a consensus committee of experts in dystonia research. The evidence and knowledge gaps are summarized and commented by the authors taking into account expert opinion and personal clinical experience for providing practical guidance in patient selection for DBS in dystonia.

RESULTS

The literature review shows that pallidal deep brain stimulation is most effective in patients with isolated dystonia irrespective of the underlying etiology. In contrast, patients with combined dystonias are less likely to benefit from DBS, because the associated neurological symptoms (e.g., hypotonia or ataxia), with the exception of myoclonus, do not respond to pallidal neurostimulation.

CONCLUSIONS

It is important to recognize the clinical features of dystonia, because the distinction between isolated and combined dystonia syndromes may predict the treatment response to pallidal deep brain stimulation. The aim of this review is to help guide clinicians with advising patients about deep brain stimulation therapy for dystonia and refering appropriate candidates to surgical centers.

Long-term follow-up of bilateral subthalamic deep brain stimulation for refractory tardive dystonia

BACKGROUND

No effective treatment for tardive dystonia (TD) has been well established. Deep brain stimulation (DBS) can ameliorate motor manifestations in primary dystonia, and may also be an effective approach for TD.

OBJECTIVES

This study aimed to illuminate the long-term efficacy and safety of subthalamic nucleus (STN)-DBS in treating TD.

METHODS

Ten patients with refractory TD underwent STN-DBS therapy and were assessed by the Burke-Fahn-Marsden dystonia rating scale (BFMDRS), Abnormal Involuntary Movement Scale (AIMS), Hamilton Depression Scale (HAMD), Hamilton Anxiety Scale (HAMA), and the Short Form (36) Health Survey (SF-36) at four time points: pre-operation, 1 week post-operation, 6 months post-operation, and at a final long-term postsurgical follow-up time point.

RESULTS

The mean follow-up time was 65.6 ± 30.4 months (range, 12-105 months). At the first follow-up, BFMDRS motor and disability scores had improved by 55.9± 28.3% and 62.6± 32.0%, respectively, while AIMS scores improved by 53.3± 26.7%. At the second follow-up, BFMDRS motor and disability scores improved further, by 87.3± 17.0% and 84.3% ± 22.9%, respectively, while AIMS scores improved by 88.4 ± 16.1%. At the last follow-up, this benefit was sustained and had plateaued. Quality of life was improved significantly at the long-term follow-up, and the HAMA and HAMD scores displayed a significant reduction that persisted after the first follow-up.

CONCLUSION

STN-DBS may be an effective and acceptable procedure for TD, leading to persistent and significant improvement in both movement and psychiatric symptoms.

Tardive Dystonia Related with Aripiprazole

Tardive dystonia is characterized by sustained, generally slow involuntary twisting movements. It is estimated to occur at a frequency of 1% to 4% among patients who are taking an antipsychotic agent. Unlike the first generation antipsychotics, the second generation antipsychotics are less likely to cause neuroleptic-induced movement disorder. For aripiprazole, only a few cases have been reported for tardive dystonia. We present a young male, who developed a severe tardive dystonia after taking aripiprazole for 5 years. The patient was admitted to for the treatment of both hisdystonic and psychotic symptoms. Olanzapine was administered instead of aripiprazole and while his psychotic symptoms improved, the dystonic symptoms were continued. Therefore, olanzapine was switched to clozapine while augmenting with benzodiazepine, anti-cholinergic, and ginko biloba to control his tardive dystonia. After 2 weeks of treatment, the dystonic movement decreased remarkably.

Clozapine Effective in Olanzapine-Induced Pisa Syndrome

Objective:

To report a case of olanzapine-induced Pisa syndrome that improved after treatment with clozapine.

Case Summary:

A 22-year-old male with paranoid schizophrenia presented with insidious onset tonic truncal flexion with axial rotation and difficulty in walking after exposure to olanzapine in doses up to 15 mg/day for 9 months. An objective causality assessment suggested that Pisa syndrome was probably related to olanzapine. There was improvement in his symptoms after 6 weeks of treatment with clozapine in doses gradually titrated to 350 mg/day.

Discussion:

Pisa syndrome is a type of dystonia that has been associated with both typical and atypical antipsychotics. Both acute and insidious onset cases have been described in the literature, which have different course and treatment response. Clozapine was found to be effective in reducing the severity of olanzapine-induced Pisa syndrome.

Conclusion:

Clozapine may be a useful treatment option for Pisa syndrome that has been caused by olanzapine.

Drug-Induced Extrapyramidal Syndromes: Implications for Contemporary Practice

The development of drugs to treat psychosis is a fascinating nexus for understanding mechanisms underlying disorders of mind and movement. Although the risk of drug-induced extrapyramidal syndromes has been mitigated by the acceptance of less potent dopamine antagonists, expansive marketing and off-label use has increased the number of susceptible people who may be at risk for these neurologic effects. Clinicians need to be familiar with advances in diagnosis and management, which are reviewed herein. A better understanding of drug-induced effects on the motor circuit may improve patient safety, enhance antipsychotic effectiveness, and provide insights into mechanisms underlying antipsychotic activity in parallel brain circuits.

Deep brain stimulation for intractable tardive dystonia: Literature overview

BACKGROUND

Tardive dystonia (TD) represents a side effect of prolonged intake of dopamine receptor blocking compounds. TD can be a disabling movement disorder persisting despite available medical treatment. Deep brain stimulation (DBS) has been reported successful in this condition although the number of treated patients with TD is still limited to small clinical studies or case reports. The aim of this study was to present the systematical overview of the existing literature regarding DBS for intractable TD.

METHODS AND RESULTS

A literature search was carried out in PudMed. Clinical case series or case reports describing the patients with TD after DBS treatment were included in the present overview. Literature search revealed 19 articles reporting 59 individuals operated for TD. GPi was the target in 55 patients, while subthalamic nucleus (STN) was the target in the remaining 4. In most studies the motor part of Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS) was improved by more than 80% when compared to preoperative BFMDRS scores.

CONCLUSIONS

The performed literature analysis indicates that bilateral GPi DBS is an effective treatment for disabling TD. The response of TD to bilateral GPi DBS may be very rapid and occurs within days/weeks after the procedure. The efficacy of bilateral GPi DBS in TD patients is comparable to results achieved in patients with primary generalized dystonia.

Antipsychotics-induced tardive syndrome: a retrospective epidemiological study

OBJECTIVES

Only little information of the epidemiology of tardive syndrome in patients using antipsychotics is available. Herein, we aimed to investigate the prevalence and risk factors of antipsychotics-induced tardive syndrome.

METHODS

This study was conducted by means of a retrospective survey. Subjects receiving antipsychotics for more than 6 months, but no other agents that may cause involuntary movements, were consecutively recruited. Tardive syndrome was evaluated in every included subject. Possible confounding medical conditions were carefully ruled out.

RESULTS

Of the 123 included subjects, 35 (28.5%) were found to have at least 1 episode of tardive syndrome. The prevalence of subtypes of tardive syndrome were as follows: tardive dyskinesia, 21.1%; tardive dystonia, 12.5%; tardive tremor, 2.4%; and tardive akathisia, 2.4%. Concurrent physical illness and a history of extrapyramidal symptoms were significant risk factors for tardive syndrome.

CONCLUSIONS

This study showed that antipsychotics may induce various types of tardive syndrome, of which tardive dyskinesia is the most predominant one. Physicians should be aware of this common and distressing adverse effect when using antipsychotics.

Glucose hypermetabolism in the thalamus of patients with drug-induced blepharospasm

We examined the difference in cerebral function alterations between drug-induced blepharospasm patients and essential blepharospasm (EB) patients by using positron emission tomography with (18)F-fluorodeoxyglucose. Cerebral glucose metabolism was examined in 21 patients with drug-induced blepharospasm (5 men and 16 women; mean age, 53.1 [range, 29-78] years), 21 essential EB patients (5 men and 16 women; mean age, 53.0 [range, 33-72] years) and 24 healthy subjects (6 men and 18 women; mean age, 57.9 [range, 22-78] years) with long-term history of benzodiazepines use (drug healthy subjects). Drug-induced blepharospasm patients developed symptoms while taking benzodiazepines or thienodiazepines. Sixty-three normal volunteers (15 men and 48 women; mean age, 53.6 [range, 20-70] years) were examined as controls. Differences between the patient groups and control group were examined by statistical parametric mapping. Additionally, we defined regions of interests on both sides of the thalamus, caudate nucleus, anterior putamen, posterior putamen and primary somatosensory area. The differences between groups were tested using two-sample t-tests with Bonferroni correction for multiple comparisons. Cerebral glucose hypermetabolism on both side of the thalamus was detected in drug-induced blepharospasm, EB patients and drug healthy subjects by statistical parametric mapping. In the analysis of regions of interest, glucose metabolism in both sides of the thalamus in the drug-induced blepharospasm group was significantly lower than that in the EB group. Moreover, we observed glucose hypermetabolism in the anterior and posterior putamen bilaterally in EB group but not in drug-induced blepharospasm group and drug healthy subjects. Long-term regimens of benzodiazepines or thienodiazepines may cause down-regulation of benzodiazepine receptors in the brain. We suggest that the functional brain alteration in drug-induced blepharospasm patients is similar to that in EB patients, and that alteration of the GABAergic system might be related to the pathology of both blepharospasm types.

Clozapine and tardive movement disorders: a review

BACKGROUND

Tardive syndromes (TS) arise from long term exposure to dopamine receptor blocking agents. Clozapine has been considered to have low risk of causing new onset TS and is considered as a treatment option in patients with TS.

AIM

This review evaluates the usefulness of clozapine in patients with TS and occasional reports of clozapine causing TS.

METHODOLOGY

Electronic searches were carried out using the search engines of PUBMED, Science direct and Google Scholar databases. All reports describing use of clozapine in management of TS, monitoring of TS while on clozapine and onset of TS after initiation of clozapine were identified.

RESULTS

Fifteen trials and 28 case series/case reports describe the use of clozapine in TS. Most of these reports show that clozapine is useful in patients with TS, in the dose range of 200-300 mg/day and the beneficial effect is seen within 4-12 weeks of initiation. One case series and two case reports described clozapine withdrawal emergent dyskinesias suggesting a masking role of clozapine. One trial, three case series and two case reports describe beneficial effects of clozapine on long standing neurological syndromes. There is relatively less literature (2 trials and 15 case series/reports) describing the emergence of TS with clozapine.

CONCLUSION

Evidence of beneficial effects of clozapine in TS is greater than its role in causation/worsening of TS. Hence, clozapine should be considered in symptomatic patients who develop TS while receiving other antipsychotics. Further research on mechanism of TS and clozapine effect on TS is required.

Globus pallidus interna deep brain stimulation for tardive dyskinesia: case report and review of the literature

Tardive dyskinesia (TD) can be a disabling condition and is frequently refractory to medical therapy. Over the past decade there have been many reports of TD patients experiencing significant benefit with deep brain stimulation (DBS) of the globus pallidus interna (GPi). The growing literature on this treatment option for TD consists predominantly of case reports and series. The reported benefit ranges widely, but the majority of cases experienced at least a 50% improvement in symptoms. The anatomical distribution of dyskinesias has not clearly influenced outcome, though fixed postures appear less likely to improve than phasic movements. Onset of benefit can be immediate or take months, and benefit is sustained in most cases, for at least 6 months and up to several years. A wide variety of voltages, frequencies, and pulse widths have demonstrated efficacy. A small number of reports which examined psychiatric symptoms before and after surgery did not find any decline, and in some cases revealed improvement in mood. However, these overall positive results should be interpreted with caution, as the majority of reports lacked blinded assessments, control groups, or standardized therapy parameters. Finally, we present an illustrative case of refractory tardive dyskinesia treated with GPi-DBS with 5 years of follow-up and 4 accompanying video segments.

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.

Bilateral deep brain stimulation of the globus pallidus internus in tardive dystonia

Tardive dystonia is a disabling movement disorder as a consequence of exposure to neuroleptic drugs. We followed 6 patients with medically refractory tardive dystonia treated by bilateral globus pallidus internus (GPi) deep brain stimulation (DBS) for 21 +/- 18 months. At last follow-up, the Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS) motor score improved by 86% +/- 14%, and the BFMDRS disability score improved by 80% +/- 12%. Bilateral GPi-DBS is a beneficial therapeutic option for the long-term relief of tardive dystonia.

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.

Extrapyramidal symptoms with atypical antipsychotics : incidence, prevention and management

The treatment of schizophrenia changed drastically with the discovery of antipsychotic medications in the 1950s, the release of clozapine in the US in 1989 and the subsequent development of the atypical or novel antipsychotics. These newer medications differ from their conventional counterparts, primarily based on their reduced risk of extrapyramidal symptoms (EPS). EPS can be categorised as acute (dystonia, akathisia and parkinsonism) and tardive (tardive dyskinesia and tardive dystonia) syndromes. They are thought to have a significant impact on subjective tolerability and adherence with antipsychotic therapy in addition to impacting function. Unlike conventional antipsychotic medications, atypical antipsychotics have a significantly diminished risk of inducing acute EPS at recommended dose ranges. These drugs may also have a reduced risk of causing tardive dyskinesia and in some cases may have the ability to suppress pre-existing tardive dyskinesia. This paper reviews the available evidence regarding the incidence of acute EPS and tardive syndromes with atypical antipsychotic therapy. Estimates of incidence are subject to several confounds, including differing methods for detection and diagnosis of EPS, pretreatment effects and issues surrounding the administration of antipsychotic medications. The treatment of acute EPS and tardive dyskinesia now includes atypical antipsychotic therapy itself, although other adjunctive strategies such as antioxidants have also shown promise in preliminary trials. The use of atypical antipsychotics as first line therapy for the treatment of schizophrenia is based largely on their reduced risk of EPS compared with conventional antipsychotics. Nevertheless, EPS with these drugs can occur, particularly when prescribed at high doses. The EPS advantages offered by the atypical antipsychotics must be balanced against other important adverse effects, such as weight gain and diabetes mellitus, now known to be associated with these drugs.

Mouvements anormaux d’origine médicamenteuse : les syndromes tardifs

Persistent drug-induced movement disorders (tardive syndromes) remain an important clinical problem and consist of a variety of involuntary movements appearing in a patient exposed to a dopamine-blocking agent. The current state of knowledge on this topic is summarised in this article. Clinical aspects (tardive dyskinesia, tardive dystonia and other forms), prevalence, risk factors, prevention and management are discussed.

Treatment of severe neuroleptic-induced tardive torticollis

Background

The aim of this paper is to describe a case of severe neuroleptic-induced tardive torticollis successfully treated with a combination of clozapine, clonazepam and botulinum toxin-A.

Case Report

The patient, a 30-year old man with a seven-year history of delusional disorder experienced severe right torticollis with painful tightness of the neck and elevation of the shoulder. At this time he was receiving haloperidol 20 mg, trifluoperazine 5 mg, zuclopenthixol 20 mg and biperidine 4 mg daily. The combination therapy with clozapine and clonazepam and the long-term use of botulinum toxin-A resulted in a complete remission of dystonic movements.

Conclusions

The present observations provide evidence indicating that this combination therapy may be of benefit in patients with severe neuroleptic-induced tardive torticollis.

Tardive dystonia and genetic polymorphisms of cytochrome P4502D6 and dopamine D2 and D3 receptors: a preliminary finding

Tardive dystonia is an uncommon but intractable and distressing complication of neuroleptic treatment. It is suggested that individual predisposing vulnerability plays a major role in the development of the side effect. This study aimed to investigate relationship tardive dystonia and several genetic factors such as polymorphism of cytochrome P4502D6, and receptor polymorphisms of dopamine D(2) (TaqI A and -141C Ins/Del polymorphisms) and D(3) (Ser(9)Gly polymorphism). Nine patients with tardive dystonia were genotyped for these genetic polymorphisms. No specific genotypes or alleles were overpresented in the patients. This study suggests that these polymorphisms are not related to the development of tardive dystonia.

Dyskinesia: L-dopa-induced and tardive dyskinesia

Neuroleptic induced tardive dyskinesia and L-dopa-induced dyskinesia are the two most common types of drug-induced abnormal involuntary movements. These two drug-induced dyskinesias are clearly different with respect to the offending drugs and the underlying disease, but they both share a number of intriguing similarities in terms of clinical phenomenology, epidemiology, risk factors, pathophysiological mechanisms and therapeutic responses. In both instances, it is believed that some dysregulation occurring at the level of the striatal dopaminergic receptors, and related non-dopaminergic neurotransmitters systems are playing a crucial role in the development and persistence of the mechanisms causing dyskinesia. These long-lasting functional changes, known as the "priming" phenomenon, are responsible for an impaired balance within the relays of the cortico-subcortical motor loops that release an inadequate output from the basal ganglia leading to an abnormal motor behavior. From a therapeutic perspective, there are also many similarities in the strategies proposed to manage these two dyskinesias. In both cases, unprimed patients not previously exposed to the offending drugs, are offered alternative medications to reduce, at least partly, the risk of occurrence of future dyskinesia: "atypical" neuroleptics in the place of "typical" neuroleptics, and dopamine agonists in the place of L-dopa. In both cases, once dyskinesias are present, in already "primed" patients, both types of dyskinesia appear to be poorly and only partly reversible. Based on limited clinical evidence, it is a common proposal to switch the dyskinetic subject from "typical" to "atypical" neuroleptics for tardive dyskinesia, or to switch from (or more pragmatically to substitute as much as possible) L-dopa to a dopamine agonist for L-dopa-induced dyskinesia. In both cases, efficacious symptomatic antidyskinetic interventions, to reduce the severity of a ready present dyskinesia, are rare. There are some uncontrolled data suggesting that dopamine depleting agents, like tetrabenazine, are possibly useful for tardive dyskinesia; however, there is more clinical evidence to support the efficacy of amantadine and functional surgery in parkinsonian patients with L-dopa-induced dyskinesia.

The current status of tardive dyskinesia

OBJECTIVE

This paper aims to provide an overview of the current knowledge on neuroleptic-induced tardive dyskinesia (TD) in relation to its clinical features, risk factors, pathophysiology and management.

METHOD

The published literature was selectively reviewed and assessed.

RESULTS

Tardive diskinesia is a common neurological side-effect of neuroleptic medication, the cumulative incidence of which increases with increasing duration of treatment. Its clinical manifestations are diverse and subsyndromes have been described. Many risk factors for TD are now recognised, but increasing age remains pre-eminent as a risk factor. The pathophysiology of TD is not completely understood. Of the neurotransmitter hypotheses, the dopamine receptor supersensitivity hypothesis and the gamma-aminobutyric acid insufficiency hypothesis are the main contenders. There is increasing recognition that TD may in fact be caused by neuroleptic-induced neuronal toxicity through free radical and excitotoxic mechanisms. The occurrence of spontaneous dyskinesias in schizophrenic patients and even healthy subjects suggests that neuroleptics act on a substratum of vulnerability to dyskinesia. As no effective treatment for TD is available, the primary emphasis is on prevention. Many drugs can be tried to reduce symptoms in established cases. The increasing use of atypical neuroleptics has raised the possibility of a lower incidence of TD in the future.

CONCLUSIONS

After four decades of clinical recognition, the pathophysiology of TD is still not understood and no effective treatment is available. Its prevention with the optimal usage of currently available drugs and regular monitoring of patients on long-term neuroleptic treatment remain the best strategies to reduce its impact.