Classification and treatment of tardive syndromes

Tardive dyskinesia

Tardive dyskinesia is a group of hyperkinetic and hypokinetic movement disorders, following the administration of dopamine receptor-blocking drugs. The severity of these syndromes varies from soft forms to the development of life-degrading situations. Phenomenologically tardive dyskinesia can be represented both in isolation and in various combinations. Recognition of these syndromes early in the development of tardive dyskinesia can optimize therapeutic treatment and reduce the risk of severe complications. As a means of treatment, deutetrabenazine or valbenazine are used as first-line drugs, with resistance to therapy and in severe cases, drugs of other groups are used (amantadine, baclofen, botulinum toxin type A, clonazepam, donepezil, gabapentin, ginkgo biloba, levetiracetam, melatonin, pregabalin, thiamine, verapamil, vitamin B6, vitamin E). Our own experience of 12 patients with tardive dystonia showed the effeciency of local injections of botulinum toxin.

Metoclopramide nasal spray for management of symptoms of acute and recurrent diabetic gastroparesis in adults

Introduction: Gastroparesis (GP) is characterized by delayed gastric emptying in the absence of mechanical obstruction. About 75% of GP patients are females. Diabetes and idiopathic are the two commonest etiologies of GP. Up to two-thirds of the GP patients do not have significant symptom responses to medical therapies, and there is a paucity of available oral prokinetic agents with only one medication approved by the U.S. Food and Drug Administration (FDA) for this indication. The oral and parenteral formulations of metoclopramide were FDA approved in 1979 to treat symptoms of acute and recurrent diabetic GP. Now, more than 40 years later, a nasal preparation of metoclopramide (Gimoti^TM) was approved in June 2020 for the same indication.Areas covered: PubMed search using the keywords 'nasal metoclopramide' and 'diabetic gastroparesis.' This article aims to provide a concise review of the pharmacology, clinical efficacy, and tolerability of nasal metoclopramide.Expert opinion: The nasal formulation can be systemically absorbed without relying on the passage through a poorly emptying stomach, thus assuring the delivery of a therapeutic dose of metoclopramide, even during episodes of vomiting. Hence, metoclopramide nasal spray has the potential to be used during an acute flare, potentially avoiding hospitalizations.

Deutetrabenazine for treatment of involuntary movements in patients with tardive dyskinesia

Introduction: Tardive dyskinesia (TD) is a hyperkinetic movement disorder that arises as a complication of exposure to dopamine receptor blocking agents. Vesicular monoamine transporter type 2 (VMAT2) inhibitors reduce dyskinesia by decreasing transport of monoamines, including dopamine, into presynaptic vesicles, leaving unpackaged dopamine to be metabolized by monoamine oxidase. Deutetrabenazine was adapted from an earlier VMAT2 inhibitor, tetrabenazine, by substituting three deuterium isotopes in place of three hydrogen isotopes at the site of metabolic degradation to improve upon the pharmacokinetics of the parent compound. Areas covered: The authors reviewed the pivotal trials examining the safety and efficacy of deutetrabenazine, as well as long-term data from an open-label extension. Also reviewed were posters and oral presentations, as well as information from the product label and the United States Food and Drug Administration. Expert opinion: Deutetrabenazine is effective at decreasing dyskinesia in TD, but drug selection and cost-effectiveness between existing VMAT2 inhibitors are evolving areas of study. Other areas of investigation include novel anti-dyskinetic agents and use of deep brain stimulation.

Management of Tardive Syndrome: Medications and Surgical Treatments

Tardive syndrome (TS) is an iatrogenic, often persistent movement disorder caused by drugs that block dopamine receptors. It has a broad phenotype including movement (orobuccolingual stereotypy, dystonia, tics, and others) and nonmotor features (akathisia and pain). TS has garnered increased attention of late because of the Food and Drug Administration approval of the first therapeutic agents developed specifically for this purpose. This paper will begin with a discussion on pathogenesis, clinical features, and epidemiology. However, the main focus will be treatment options currently available for TS including a suggested algorithm based on current evidence. Recently, there have been significant advances in TS therapy, particularly with the development of 2 new vesicular monoamine transporter type 2 inhibitors for TS and with new data on the efficacy of deep brain stimulation. The discussion will start with switching antipsychotics and the use of clozapine monotherapy which, despite the lack of higher-level evidence, should be considered for the treatment of psychosis and TS. Anti-dyskinetic drugs are separated into 3 tiers: 1) vesicular monoamine transporter type 2 inhibitors, which have level A evidence, are approved for use in TS and are recommended first-choice agents; 2) drugs with lower level of evidence for efficacy including clonazepam, Ginkgo biloba, and amantadine; and 3) drugs that have the potential to be beneficial, but currently have insufficient evidence including levetiracetam, piracetam, vitamin B6, melatonin, baclofen, propranolol, zolpidem, and zonisamide. Finally, the roles of botulinum toxin and surgical therapy will be examined. Current therapies, though improved, are symptomatic. Next steps should focus on the prevention and reversal of the pathogenic process.

Current treatment of tardive dyskinesia

Tardive dyskinesia (TD) is a common, iatrogenic movement disorder affecting many individuals treated with dopamine-receptor blocking agents (DRBAs). Studying treatment of TD can be complex, as the symptoms can be affected by changes in either dosage or type of DRBA, as well as by the variable natural course of the disease. Historically many pharmacological therapies have been studied in TD, finding varying degrees of treatment success. Most recently, the VMAT2 inhibitors valbenazine and deutetrabenazine were rigorously studied in TD in large, phase III clinical trials, and were shown to be beneficial in this population. In this article, we will review various treatments of TD, including manipulation of the offending agent, VMAT2 inhibitors, other non-VMAT2-inhibiting medications, and non-pharmacological approaches.

Changes in recruitment of motor cortex excitation and inhibition in patients with drug-induced tardive syndromes

OBJECTIVES

It has recently been suggested that drug-induced tardive syndromes (TS) might be due to maladaptive plasticity, which increases motor excitability in cerebral cortex and basal ganglia. In order to test this hypothesis, we performed the first measurements of cortical excitability in TS.

METHODS

Motor cortex excitability was examined using transcranial magnetic stimulation (TMS) in 22 TS patients and compared with that in 20 age and sex-matched healthy individuals. Resting and active motor threshold (RMT, AMT) and input-output curves (I/O curves) assessed corticospinal excitability. The duration of the contralateral silent period (cSP) at a range of stimulation intensities and ipsilateral silent period (iSP) were used as measures of inhibition.

RESULTS

There were no significant differences in RMT and AMT between patients and controls, although the input-output curves were significantly steeper in patients. The cSP (at different stimulus intensities) and iSP were both longer in the patients compared to the control group. However, most of this difference could be accounted for by increased recruitment of motor evoked potentials (MEPs) in patients.

CONCLUSION

TS is characterized by hyperexcitability of corticospinal output that might contribute to the lack of selectivity in muscle recruitment and contribute to excess involuntary movement. The findings are opposite to those in naturally-occurring hyperkinesia such as Sydenham's and Huntington's chorea, suggesting a fundamental difference in the pathophysiology.

Calcium channel blockers for antipsychotic-induced tardive dyskinesia

BACKGROUND

Schizophrenia and related disorders affect a sizable proportion of any population. Antipsychotic medications are the primary treatment for these disorders. Antipsychotic medications are associated with a variety of adverse effects including tardive dyskinesia. Dyskinesia is a disfiguring movement disorder of the orofacial region that can be tardive (having a slow or belated onset). Tardive dyskinesia is difficult to treat, despite experimentation with several treatments. Calcium channel blockers (diltiazem, nifedipine, nimodipine, verapamil, flunarizine) have been among these experimental treatments.

OBJECTIVES

To determine the effects of calcium channel blocker drugs (diltiazem, nifedipine, nimodipine, verapamil) for treatment of neuroleptic-induced tardive dyskinesia in people with schizophrenia, schizoaffective disorder or other chronic mental illnesses.

SEARCH METHODS

We searched the Cochrane Schizophrenia Group Trials Register (July 2015 and April 2017), inspected references of all identified studies for further trials and contacted authors of trials for additional information.

SELECTION CRITERIA

We selected randomised controlled trials comparing calcium channel blockers with placebo, no intervention or any other intervention for people with both tardive dyskinesia and schizophrenia or serious mental illness who remained on their antipsychotic medication.

DATA COLLECTION AND ANALYSIS

We independently extracted data and estimated risk ratios of dichotomous data or mean differences (MD) of continuous data, with 95% confidence intervals (CI). We assumed that people who left the trials early had no improvement. We also created a 'Summary of findings' table using GRADE.

MAIN RESULTS

Previous versions of this review included no trials. From the 2015 search, we identified three cross-over trials that could be included. The 2017 search found no new studies relevant to this review. The included trials randomised 47 inpatients with chronic mental illnesses in the USA and China. Trials were published in the 1990s and were of short duration (six to 10 weeks). Overall, the risk of bias was unclear, mainly due to poor reporting; allocation concealment was not described, generation of the sequence was not explicit, studies were not clearly blinded, and attrition and outcome data were not fully reported. Findings were sparse, no study reported on the primary outcome 'no clinically important improvement in tardive dyskinesia symptoms,' but two small studies (37 participants) found no difference on the tardive dyskinesia symptoms scale Abnormal Involuntary Movement Scale (AIMS) scores between diltiazem or flunarizine and placebo after three to four weeks' treatment (MD -0.71, 95% CI -2.68 to 1.26, very low quality evidence). Only one study randomising 20 participants reported on adverse events, and reported that there were no adverse events with flunarizine or with placebo (very low quality evidence). One study with 18 participants reported no events of deterioration in mental state with diltiazem or with placebo (very low quality evidence). No studies reported on acceptability of treatment or on social confidence, social inclusion, social networks or personalised quality of life outcomes designated important to patients.

AUTHORS' CONCLUSIONS

Available evidence from randomised controlled trials is extremely limited and very low quality, conclusions cannot be drawn. The effects of calcium channel blockers for antipsychotic-induced tardive dyskinesia are unknown. Their use is experimental and should only be given in the context of well-designed randomised trials.

Updating the recommendations for treatment of tardive syndromes: A systematic review of new evidence and practical treatment algorithm

BACKGROUND

Management of tardive syndromes (TS) is challenging, with only a few evidence-based therapeutic algorithms reported in the American Academy of Neurology (AAN) guideline in 2013.

OBJECTIVE

To update the evidence-based recommendations and provide a practical treatment algorithm for management of TS by addressing 5 questions: 1) Is withdrawal of dopamine receptor blocking agents (DRBAs) an effective TS treatment? 2) Does switching from typical to atypical DRBAs reduce TS symptoms? 3) What is the efficacy of pharmacologic agents in treating TS? 4) Do patients with TS benefit from chemodenervation with botulinum toxin? 5) Do patients with TS benefit from surgical therapy?

METHODS

Systematic reviews were conducted by searching PsycINFO, Ovid MEDLINE, PubMed, EMBASE, Web of Science and Cochrane for articles published between 2012 and 2017 to identify new evidence published after the 2013 AAN guidelines. Articles were classified according to an AAN 4-tiered evidence-rating scheme. To the extent possible, for each study we attempted to categorize results based on the description of the population enrolled (tardive dyskinesia [TD], tardive dystonia, tardive tremor, etc.). Recommendations were based on the evidence.

RESULTS AND RECOMMENDATIONS

New evidence was combined with the existing guideline evidence to inform our recommendations. Deutetrabenazine and valbenazine are established as effective treatments of TD (Level A) and must be recommended as treatment. Clonazepam and Ginkgo biloba probably improve TD (Level B) and should be considered as treatment. Amantadine and tetrabenazine might be considered as TD treatment (Level C). Pallidal deep brain stimulation possibly improves TD and might be considered as a treatment for intractable TD (Level C). There is insufficient evidence to support or refute TS treatment by withdrawing causative agents or switching from typical to atypical DRBA (Level U).

Tardive dyskinesia: Epidemiology

The term tardive syndrome (TS) encompasses a few different phenomenologic conditions, some of which occur in isolation and others in association with each other. This, along with the unusual confound for a drug side effect, in which increased use of the drug improves the problem, and the need for most patients to continue taking the offending drug, makes understanding the epidemiology difficult and unreliable. While the change from the "first generation" to the "second generation" of antipsychotic drugs is generally believed to have reduced the incidence of TS, prospective research studies have not supported that contention. Published reports have found point prevalences of 13% with second generation antipsychotics and 32% with first, yet others have found no differences. One study found increasing rates of TS with a 68% prevalence by 25 years, while another found a decreased prevalence over time, due presumably to masking effects of the antipsychotic drugs. Regardless of the possible differences, it is clear that TS remains a significant and common problem associated with almost all antipsychotic drugs. There have also been scattered reports of TS caused by drugs not known to inhibit dopamine receptors. These are reviewed and were found to be often of dubious reliability.

Reported time to onset of neurological adverse drug reactions among different age and gender groups using metoclopramide: an analysis of the global database Vigibase®

PURPOSE

Despite FDA and EMA warnings of long-term use, little is known regarding the time to onset (TTO) of neurological adverse drug reactions (ADR) for metoclopramide. The aims of this study were, first, to evaluate whether neurological ADRs are more commonly reported for metoclopramide than for other medications, and second, to describe how time to onset of neurological ADRs differs by age and gender.

METHODS

All ADR reports with metoclopramide as the suspected/interacting drug were extracted from the WHOs Global ADR database Vigibase® between 1967 and May 2016. Cox proportional hazards models were fit using TTO of neurological ADRs as the outcome and age, gender, and type of ADR as predictors. Proportional Reporting Ratios (PRRs) for neurological ADRs were compared across age and gender. Lawyer reports were excluded in the analysis.

RESULTS

Over 47,000 ADR reports with metoclopramide were identified. Over one third (35.6%) of the reports came from lawyers. The majority of ADRs in general and neurological ADRs in specific occurred within the first 5 days of metoclopramide use (median 1 day). TTO increased with age. Neurological ADRs were reported two to four times as frequently for metoclopramide than for other drugs, with the highest PRRs observed in children (PRR = 4.24 for girls and 4.60 for boys).

CONCLUSIONS

Most adverse drug reactions occur within the first 5 days of treatment with metoclopramide. Patients requiring use of metoclopramide should be carefully monitored for neurological ADRs during the first days of treatment.

Antipsychotic-induced Tardive dyskinesia: from biological basis to clinical management

INTRODUCTION

Tardive dyskinesia (TD) is a chronic and disabling movement disorder with a complex pathophysiological basis. A significant percentage of patients does not receive correct diagnosis, resulting in delayed or inaccurate treatment and poor outcome. Therefore, there is a critical need for prompt recognition, implementation of efficacious treatment regimens and long-term follow up of patients with TD. Areas covered: The current paper provides an overview of emerging data concerning proposed pathophysiology theories, epidemiology, risk factors, and therapeutic strategies for TD. Expert commentary: Despite considerable research efforts, TD remains a challenge in the treatment of psychosis as the available strategies remain sub-optimal. The best scenario will always be the prophylaxis or prevention of TD, which entails limiting the use of antipsychotics.

Unusual morphology of scapulae: incidence and dimensions of ossified ligaments and supraspinous bony tunnels for clinical consideration

INTRODUCTION

Knowledge of morphological variations of the suprascapular region is important in the management of entrapment neuropathy and interventional procedures. The objective of this study was to collect data on the morphological features and dimensions of ossified ligaments and unusual bony tunnels of scapulae from a North Indian population.

METHODS

A total of 268 adult human scapulae of unknown gender were obtained from the bone bank of the Department of Anatomy, Dayanand Medical College and Hospital, Ludhiana, Punjab, India. The scapulae were evaluated for the incidence of ossified superior transverse scapular ligaments (STSLs), ossified inferior transverse scapular ligaments (ITSLs) and bony tunnels (i.e. the bony canal between the suprascapular notch and spinoglenoid notch), found along the course of the suprascapular nerve (SSN). The dimensions of these structures were measured and noted down. Ossified STSLs were classified based on their shape (i.e. fan- or band-shaped) and the dimensions of the ossified suprascapular openings (SSOs) were measured.

RESULTS

Ossified STSLs were present in 26 (9.7%) scapulae. Among the 26 scapulae, 16 (61.5%) were fan-shaped (mean area of SSO 16.6 mm(2)) and 10 (38.5%) were band-shaped (mean area of SSO 34.2 mm(2)). Bony tunnels were observed in 2 (0.75%) specimens, while an ossified ITSL was observed in 1 (0.37%) specimen.

CONCLUSION

The data obtained in the present study augments the reference literature for SSN decompression and the existing anatomical databases, especially those on Indian populations. This data is useful to clinicians, radiologists and orthopaedic surgeons.

Clozapine Treatment of Olanzapine-induced Tardive Dyskinesia: A Case Report

Tardive dyskinesias (TD) are serious, often irreversible side effects of dopamine blocking agents, most commonly first-generation antipsychotics. No definitive treatment exists, with different interventions showing inconsistent results. We report a case of TD presenting after 12 years of olanzapine therapy in a 66-year-old Hispanic male with paranoid schizophrenia. The TD symptoms were successfully treated within a few weeks by switching to clozapine. Two cases of olanzapine-induced TD treated with clozapine have previously been reported, but in those cases, the symptom onset was quicker, ranging from a few months to a few years after initiation of olanzapine therapy, and the treatment response was relatively slower. Clinicians should carefully monitor for symptoms of TD after prolonged treatment with olanzapine and other antipsychotics. If otherwise indicated for psychiatric treatment, clozapine can be considered a good choice for patients with TD in preventing or reversing the debilitating consequences of this condition.

[Prevention and treatment of tardive dyskinesia caused by antipsychotic drugs]

INTRODUCTION

Tardive dyskinesia (TD) is a movement disorder of tongue, jawbone, trunk and/or limbs that may appear after a prolonged use of dopamine receptor blocking agents (after 3 months of treatment or after 1 month for patients over 60), and that are present during at least four consecutive weeks. TD is a frequent side effect of both classical neuroleptics and new generation antipsychotic drugs. The prevalence of iatrogenic TD is between 24 and 32 % after treatment with classical neuroleptics and about 13 % after treatment with a new generation antipsychotic.

OBJECTIVE

This paper presents an updated literature review of data on diagnosis, prevention and treatment of TD.

METHODS

We conducted a review of literature using the Medline Browser tool, screening studies from 1950 to 2013 in English or French with keywords « tardive dyskinesia », « tardive dystonia », and « abnormal movements caused by antipsychotic drugs ».

RESULTS

We first describe and define semeiological features of TD: dystonia, tremor, myoclonus, acathisie, chorea, ballism and athetosia. Secondarily, we resume the main differential diagnoses to exclude when confronted with this kind of movement disorders. Differential diagnoses for dyskinesia can be classified between primary (Parkinson and Huntington diseases) and secondary (Wilson disease, intoxication, metabolic abnormality, cerebrovascular accident) abnormal movements. Psychogenic TD can be evocated if previous pathologies are excluded in case of atypical clinical presentation. We detail the risk factors for TD. Endogenous risk factors are related to the patient's age, underlying psychiatric disease (bipolar disorder or Alzheimer dementia), addiction to alcohol or cocaine, female gender, or neurodevelopmental vulnerability. Iatrogenic risk factors are high doses of antipsychotics, long or intermittent administration, and particular pharmaceutical classes or associations of antipsychotics. As a comprehensive tool, we review the main physiopathological hypotheses to explain the occurrence of TD in some patients: hypersensitivity of D2 neuronal receptor or neurotoxicity associated with oxidative stress mechanisms. We also summarize the current guidelines for prevention and treatment of TD. Three successive curative strategies are suggested in the literature. First, the clinician can adapt the current antipsychotic treatment (switch to a new generation antipsychotic, diminution or cessation of antipsychotic drugs). If this first intervention is not pertinent or ineffective, the clinician can prescribe an antikinetic therapeutic agent, such as tetrabenazine, or an antioxidant. Review of the published studies does not show proof of efficacy of cholinergic or anticholinergic drugs, benzodiazepine or other GABAergic drugs, nor for amantadine. Non-medication therapeutics such as ECT and TMS are discussed, but the level of proof is insufficient to promote them as a curative treatment for TD. In case of high resistance and discomfort for the patient, a neurosurgical intervention should be discussed. These curative interventions are limited, emphasising the importance of TD prevention, by limiting the prescription and doses of antipsychotics, regularly evaluating their side effects and informing the patient of TD's risk.

CONCLUSION

We propose to practitioners a synthesised update of literature concerning a frequent iatrogenic effect of antipsychotics. Nevertheless, no solid guidelines have as yet been established, and further clinical studies are expected in order to better understand this frequent and discomforting side effect.

Drug-induced movement disorders

INTRODUCTION

Drug-induced movement disorders (DIMDs) can be elicited by several kinds of pharmaceutical agents. The major groups of offending drugs include antidepressants, antipsychotics, antiepileptics, antimicrobials, antiarrhythmics, mood stabilisers and gastrointestinal drugs among others.

AREAS COVERED

This paper reviews literature covering each movement disorder induced by commercially available pharmaceuticals. Considering the magnitude of the topic, only the most prominent examples of offending agents were reported in each paragraph paying a special attention to the brief description of the pathomechanism and therapeutic options if available.

EXPERT OPINION

As the treatment of some DIMDs is quite challenging, a preventive approach is preferable. Accordingly, the use of the offending agents should be strictly limited to appropriate indications and they should be applied in as low doses and as short duration as the patient's condition allows. As most of DIMDs are related to an unspecific adverse action of medications in the basal ganglia and the cerebellum, future research should focus on better characterisation of the neurochemical profile of the affected functional systems, in addition to the development of drugs with higher selectivity and better side-effect profile.

Identification and management of tardive dyskinesia: A case series and literature review

Tardive dyskinesia (TD) is a serious, disabling and potentially permanent, neurological hyperkinetic movement disorder that occurs after months or years of taking dopamine receptor-blocking agents. The pathophysiology of TD is complex, multifactorial and still not fully understood. Although there is no identified effective and standard treatment for TD, several agents have been tried for the management of this motor disturbance. The aim of this case series is to review the literature in regard to the identification, diagnosis and the treatment of TD with anticholinergics, anticholinergic medication withdrawal, cholinergic agents, botulinum toxin intramuscular injections, tetrabenazine, levetiracetam, propranolol and zolpidem, and to describe one case of TD that responded favorably to clonazepam and two cases of TD that responded favorably to Ginkgo biloba.

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.

Management of tardive syndromes with clozapine: a case series

Tardive syndromes are among the most debilitating side effects associated with use of antipsychotics. In this case series we present 5 cases of drug induced tardive syndromes, who had not responded to many of the other therapeutic measures but responded to clozapine. The response rate with clozapine varied from 50% to 100% and the response was seen by week 3 in most cases. Over the long term follow-up of as long as 6 years the response to clozapine was sustained. In two cases clozapine could be stopped.

A severe and irreversible case of tardive rigid-akinetic parkinsonian syndrome: the role of the DaTscan

In elderly patients, exposure to antipsychotic medication and subsequent withdrawal may lead to the development of persistent extrapyramidal symptoms, possibly including a syndrome suggested to be tardive parkinsonism. We describe a case in which withdrawal of antipsychotics was unexpectedly associated with progressive deterioration, rather than improvement, of extrapyramidal parkinsonian symptoms. Abnormal imaging of presynaptic dopamine transporters (DaTs) using single-photon emission computed tomography (SPECT) with ioflupane I 123 (DaTscan) substantially contributed to the differential diagnosis, suggesting it was likely that the patient had an underlying neurodegenerative disorder that preceded the onset of medicationinduced parkinsonian symptoms. Our report illustrates how novel findings from DaTscan may assist with diagnosing the cause of persistent parkinsonian symptoms after antipsychotic withdrawal and provide insight into the controversial concept of tardive parkinsonism.

An update on tardive dyskinesia: from phenomenology to treatment

Tardive dyskinesia (TD), characterized by oro-buccal-lingual stereotypy, can manifest in the form of akathisia, dystonia, tics, tremor, chorea, or as a combination of different types of abnormal movements. In addition to movement disorders (including involuntary vocalizations), patients with TD may have a variety of sensory symptoms, such as urge to move (as in akathisia), paresthesias, and pain. TD is a form of tardive syndrome-a group of iatrogenic hyperkinetic and hypokinetic movement disorders caused by dopamine receptor-blocking agents. The pathophysiology of TD remains poorly understood, and treatment of this condition is often challenging. In this update, we provide the most current information on the history, nomenclature, etiology, pathophysiology, epidemiology, phenomenology, differential diagnosis, and treatment of TD.

Tics and other stereotyped movements as side effects of pharmacological treatment

Tics and other stereotyped abnormal movements can be seen as adverse effects of some pharmacologic drugs. Among these drugs, antipsychotics may provoke tardive syndromes after a chronic exposure, primarily in the case of typical antipsychotics. These syndromes include tardive tics, tardive dyskinesia, or tardive akathisia, which present with tics or stereotyped movements as a clinical phenomenon. Psychostimulants (mainly methylphenidate) have traditionally been associated with the appearance of tics due to the increased dopamine activity caused by stimulants. Nevertheless, in recent years, several studies have concluded not only that methylphenidate does not exacerbate or reactivate tics but also that tics can improve with its use in patients with associated attention deficit and hyperactivity disorder and tic disorder. Antiepileptic drugs, although infrequently, can also induce tics, with carbamazepine and lamotrigine described as tic inducers. Other antiepileptics, including levetiracetam and topiramate, have been proposed as a potential treatment for tic disorders due to a positive effect on tics, especially in those with associated epileptic disorder. Clinical and therapeutic approaches to tics and stereotyped movements after exposure to antipsychotics, stimulants, and antiepileptic drugs will be reviewed in this chapter.

Systematic drug repositioning based on clinical side-effects

Drug repositioning helps fully explore indications for marketed drugs and clinical candidates. Here we show that the clinical side-effects (SEs) provide a human phenotypic profile for the drug, and this profile can suggest additional disease indications. We extracted 3,175 SE-disease relationships by combining the SE-drug relationships from drug labels and the drug-disease relationships from PharmGKB. Many relationships provide explicit repositioning hypotheses, such as drugs causing hypoglycemia are potential candidates for diabetes. We built Naïve Bayes models to predict indications for 145 diseases using the SEs as features. The AUC was above 0.8 in 92% of these models. The method was extended to predict indications for clinical compounds, 36% of the models achieved AUC above 0.7. This suggests that closer attention should be paid to the SEs observed in trials not just to evaluate the harmful effects, but also to rationally explore the repositioning potential based on this “clinical phenotypic assay”.

Calcium channel blockers for neuroleptic-induced tardive dyskinesia

BACKGROUND

Schizophrenia and related disorders affect a sizable proportion of any population. Neuroleptic (antipsychotic) medications are the primary treatment for these disorders. Neuroleptic medications are associated with a variety of side effects including tardive dyskinesia. Dyskinesia is a disfiguring movement disorder of the orofacial region that can be tardive (having a slow or belated onset). Tardive dyskinesia is difficult to treat, despite experimentation with several treatments. Calcium channel blockers (diltiazem, nifedipine, nimodipine, verapamil) have been among these experimental treatments.

OBJECTIVES

To determine the effects of calcium-channel blocker drugs (diltiazem, nifedipine, nimodipine, verapamil) for treatment of neuroleptic-induced tardive dyskinesia in people with schizophrenia, schizoaffective disorder or other chronic mental illnesses.

SEARCH STRATEGY

We updated previous searches in May 2010 by searching the Cochrane Schizophrenia Group Register using the Cochrane Schizophrenia Group search strategy.

SELECTION CRITERIA

Randomised clinical trials comparing calcium-channel blockers with placebo, no intervention or any other intervention for people with both tardive dyskinesia and schizophrenia or serious mental illness.

DATA COLLECTION AND ANALYSIS

We planned to extract and analyse data on an intention-to-treat (ITT) basis. We intended to calculate the relative risk (RR) and 95% confidence intervals (CI) of homogeneous dichotomous data using a random-effects model, and, where possible, calculate the number needed to treat. We planned to calculate mean differences (MD) for continuous data.

MAIN RESULTS

We did not include any trials in this review. We excluded 15 studies; eight were not randomised, one did not use calcium channel blockers, five small, randomised, studies reported no usable data and one did not include people with both tardive dyskinesia and schizophrenia.

AUTHORS' CONCLUSIONS

The effects of calcium-channel blockers for antipsychotic induced tardive dyskinesia are unknown. Their use is experimental and should only be given in the context of well designed randomised clinical trials.

Receptor screening technologies in the evaluation of Amazonian ethnomedicines with potential applications to cognitive deficits

ETHNOPHARMACOLOGICAL RELEVANCE

Amazonian peoples utilize a variety of psychoactive plants that may contain novel biologically active compounds. Efforts to investigate such remedies in terms of neuropharmacology have been limited.

AIM OF THIS STUDY

This study identified Amazonian ethnomedicines with potential for the treatment of cognitive deficits in schizophrenia and dementias, and characterized their interactions with CNS neurotransmitter receptors in vitro.

MATERIALS AND METHODS

Approximately 300 Amazonian species with folk uses or constituents indicative of central nervous system activity were incorporated into a database constructed from literature searches, herbarium surveys, and interviews with traditional practitioners. Approximately 130 of these targeted species were collected in Loreto province, Peru, and 228 fractions derived from them were screened in 31 radioreceptor assays via the resources of the NIMH Psychoactive Drug Screening Program. A subset was also screened in functional assays at selected serotonin, muscarinic, and adrenergic receptors.

RESULTS

Ninety-one samples displayed ≥60% inhibition of radioligand binding activity in receptor assays; 135 samples displayed agonist or antagonist activity (or both) in functional assays.

CONCLUSIONS

Potential CNS activity was detected in about 40% of the samples screened, with some correlations to both folk uses and phytochemical constituents. These results may point to novel and potentially therapeutic CNS active compounds.

A case of schizophrenia with dysphagia successfully treated by a multidimensional approach

Dysphagia in patients with psychiatric illnesses contributes to morbidities and mortalities. It is, however, an overlooked problem in clinical practice. We report a patient of schizophrenia with dysphagia who was successfully treated using a multidimensional approach, which included medication adjustment, swallowing training and diet modification.

The current prevalence and factors associated with tardive dyskinesia among Filipino schizophrenic patients

OBJECTIVE

To determine the prevalence of and the factors associated with tardive dyskinesia (TD) among Filipino patients with schizophrenia admitted at the National Center for Mental Health.

STUDY DESIGN

Cross-sectional study.

METHODS

A total of 227 inpatients fulfilling the DSM-IV TR criteria for schizophrenia participated in the study. Demographic data including age, disease duration and medication intake were obtained. The Abnormal Involuntary Movement Scale (AIMS) and Simpson Angus Rating Scale (SARS) were performed on all patients. Odds of developing TD in relation to the different variables were computed. The association between study variables and development of TD was also evaluated using the Chi-square test.

FINDINGS

Our cohort of patients had a mean age of 40 (range: 19-73 years old), had a mean disease duration of 6 years, had a daily neuroleptic dose of 700 mg in chlorpromazine equivalent, and had a lifetime neuroleptic exposure of at least 5 years. The prevalence rate of TD was 20.3% (46 out of 227 patients). Fifty-three percent of patients had significant extrapyramidal features (SARS > or =3). TD was noted more in females and older age groups. The other factors associated with TD: were those patients with longer duration of illness and those patients with longer cumulative exposure to neuroleptic drugs. There was no association found with regard to the presence of diabetes mellitus type II, to the use of anticholinergic drugs, to the history of substance abuse and to the history of electroconvulsive therapy.

CONCLUSIONS

Despite the predominant use of first-generation antipsychotic agents, the prevalence of TD among Filipino schizophrenic patients is similar to that reported among Asians, but lower than that reported among our Western counterparts. The results may be affected by differences in methodological, racial and genetic determinants.

Treatment of tardive dyskinesia with levetiracetam in a transplant patient

OBJECTIVE

To describe successful treatment of tardive dyskinesia with levetiracetam.

BACKGROUND

Tardive dyskinesia is a late-onset movement disorder caused by exposure to dopamine receptor blocking agents, most commonly neuroleptics. Metoclopramide is frequently used to treat gastrointestinal dysmotility. It has antidopaminergic properties, and is estimated to be responsible for two-thirds of drug-related movement disorders.

DESIGN/METHODS

Case report.

RESULTS

A 68-year-old woman presented with a history of intestinal transplantation (12 years ago; short gut syndrome related to bowel resection for rectal carcinoma) and renal transplantation (1 year ago; diabetes). She developed involuntary movements with stereotypic oro-buccal-lingual dyskinesias and right-sided choreiform movements. Her Abnormal Involuntary Movement Scale score (AIMS) score was 27. She has been treated with metoclopramide for gastrointestinal dysmotility for more than 10 years and was diagnosed with tardive dyskinesia. Treatment with levetiracetam 250 mg orally b.i.d. led to a significant improvement of abnormal movements within a week. Her AIMS score decreased to 8.

DISCUSSION

Tardive dyskinesia may be quite disabling and options include withdrawal of offending medication, or use of tetrabenazine or reserpine. Several reports also suggested improvement of tardive movement disorders with levetiracetam. In our patient, levetiracetam relieved symptoms of tardive dyskinesia and allowed continuous use of metoclopramide. Larger studies are needed to confirm its efficacy.

Four oral motor disorders: bruxism, dystonia, dyskinesia and drug-induced dystonic extrapyramidal reactions

This article reviews four of the involuntary hyperkinetic motor disorders that affect the orofacial region: bruxism, orofacial dystonia, oromandibular dyskinesia, and medication-induced extrapyramidal syndrome-dystonic reactions. It discusses and contrasts the clinical features and management strategies for spontaneous, primary, and drug-induced motor disorders in the orofacial region. The article provides a list of medications that have been reported to cause drug-related extrapyramidal motor activity, and discusses briefly the genetic and traumatic events that are associated with spontaneous dystonia. Finally, it presents an approach for management of the orofacial motor disorders. The contraindications, side effects, and usual approach for medications and injections are covered. An overview of the indications, contraindications, and complications of using botulinum toxin as a therapeutic modality is discussed briefly.

A blessing in disguise: Resolution of tardive dyskinesia with development of cervical myelitis

Tardive dyskinesia (TD), which is frequently seen in patients treated with dopamine receptor blocking agents, is difficult to manage. We report on a young Chinese man with bipolar disorder who developed TD after haloperidol treatment, involving the trunk, limbs, and orofacial area. TD persisted despite switching to atypical antipsychotic agents and treatment with valproate, benzodiazepines, and tetrabenazine. Resolution only occurred years later when he developed quadriplegia arising from infective myelitis of the cervical cord (C4-5). He had concomitant vertebral osteomyelitis, which was successfully treated with intravenous antibiotics. With intensive rehabilitation, he recovered the use of his limbs, but had no recurrence of TD. We attribute the resolution of orofacial dyskinesias with a cervical lesion to the interconnections between the orofacial area and cervical spine via the trigeminal nucleus (which has fibers descending as far caudally as C6), as well as to resetting of cortical maps.

Tardive dystonia

Tardive dyskinesia is a movement disorder that develops after exposure to dopamine receptor blocking agents. Less well-appreciated are other, more recently described tardive syndromes that are phenomenologically distinct from tardive dyskinesia and respond to different treatments. Patients may simultaneously have more than one tardive syndrome. Major subtypes of tardive syndromes include tardive dyskinesia, characterized by orobuccolingual, truncal, or appendicular, choreiform movements; tardive dystonia, characterized by sustained, stereotyped muscle spasms of a twisting or turning character; and tardive akathisia, characterized by an inner sense of restlessness or unease. The sensation often is unpleasant and may be accompanied by repetitive, purposeless movements (stereotypies), such as pacing. Less common tardive syndromes include tardive myoclonus, tardive tourettism, and tardive tremor. Tardive syndromes often are a source of great distress and disability to patients and may be permanent, despite discontinuing the responsible medication. Prevention, early detection, and prompt management are the major clinical focus. When a patient develops a tardive syndrome appropriate actions include 1) review of the primary diagnosis that prompted starting a dopamine receptor blocking agent; 2) characterization of the movement disorder(s); 3) where possible, discontinuation of dopamine blocking agent or replacement with a less potent alternative agent; 4) gradual withdrawl of the offending drug because some patients have an exacerbation of a tardive syndrome after abrupt withdrawal; and 5) assessment of the severity of symptoms and development of a treatment plan based on the phenomenology, with the goal of maximizing patient comfort and function. Although tardive dyskinesia typically develops after chronic exposure to dopamine receptor blocking agents, it, and other variants (such as tardive dystonia) can develop very rapidly after treatment. There seems to be no minimal safe duration of exposure for the development of a tardive syndrome. It is important to recognize that anti-emetics, which are dopamine receptor blockers, such as prochlorperazine, promethazine and metoclopramide, can cause tardive syndromes. Clinicians should become familiar with antipsychotic agents that have a lower risk of causing tardive syndromes, such as clozapine, quetiapine, and olanzapine. We review treatment options for tardive dystonia.

Circadian-dependent effect of melatonin on dopaminergic D2 antagonist-induced hypokinesia and agonist-induced stereotypies in rats

Although a melatonin/dopamine relationship has been well established in nonmotor systems wherein dopamine and melatonin share an antagonist relationship, less clear is the role melatonin may play in extrapyramidal dopaminergic function. Therefore, the purpose of the present experiments was to examine the relationship between melatonin and the dopaminergic D2 receptor system and behavior. Hypokinesia was induced in male Sprague-Dawley rats with fluphenazine (D2 antagonist, 0.4 mg/kg ip) and stereotypies with apomorphine (D2 agonist, 0.6 mg/kg sc) during the light (1200 h) and dark (2200 h) phases. As expected, fluphenazine induced severe hypokinesia during the light phase (482 +/- 176 s); however, unexpectedly, fluphenazine-induced hypokinesia during the dark was almost nonexistent (25 +/- 6 s). Furthermore, melatonin treatment (30 mg/kg ip) produced a strong interaction with fluphenazine in that it reduced fluphenazine-induced hypokinesia by nearly 80% in the light (112 +/- 45 s) but paradoxically increased the minimal fluphenazine-induced hypokinesia in the dark by more than 60% (70 +/- 17 s). Melatonin also reduced apomorphine-induced stereotypies by nearly 40% in the light but had no effect in the dark. Taken together, these data show (1) a strong and unexpected nocturnal effect of fluphenazine on hypokinesia and (2) provide support for an antagonistic melatonin/dopaminergic interaction in the context of motor behavior and D2 receptor function which appears to be critically dependent on the light/dark status of the dopaminergic system.