Diabetes and development of tardive dyskinesia

Current perspectives on the epidemiology and burden of tardive dyskinesia: a focused review of the clinical situation in Japan

Tardive dyskinesia (TD) is a movement disorder that can develop with the use of dopamine receptor-blocking agents and is most commonly caused by antipsychotics. The use of antipsychotics is expanding, which may lead to an increased number of patients experiencing TD. To summarise the current knowledge of the epidemiology and risk factors for TD in Japan, we reviewed articles related to the current state of knowledge around TD identified through a PubMed search, and held a roundtable discussion of experts in Japan on 9 September 2021 to form the basis of the opinion presented within this review. The true prevalence of TD among patients treated with antipsychotics is not well characterised; it is reported to be between 15% and 50% globally and between 6.5% and 7.7% in Japan. Potential barriers to timely treatment of TD include the stigma surrounding mental health issues and the lack of data regarding TD in Asian patients. This review summarises the current knowledge of the epidemiology, challenges to TD diagnosis and risk factors for TD in Japan. Recent strategies for symptom monitoring and early diagnosis, as well as consensus recommendations are included. Achieving a high level of awareness of TD among physicians who treat patients with psychiatric disorders is of great importance and physicians should ensure that patients with psychiatric disorders receiving antipsychotics are proactively monitored for signs of TD.

PLAIN LANGUAGE SUMMARY

Plain Language Summary (In Japanese).

VISUAL SUMMARY

Visual Summary (In Japanese).

Gastroparesis, metoclopramide, and tardive dyskinesia: Risk revisited

BACKGROUND

Metoclopramide is primarily a dopamine receptor antagonist, with 5HT₃ receptor antagonist and 5HT₄ receptor agonist activity, and used as an antiemetic and gastroprokinetic since almost 50 years. Regulatory authorities issued restrictions and recommendations regarding long-term use of the drug at oral doses exceeding 10 mg 3-4 times daily because of the risk for development of tardive dyskinesia. The aim of our study was to review mechanism(s) of action and pharmacokinetic-pharmacodynamic properties of metoclopramide, as well as the risk of metoclopramide-induced tardive dyskinesia, factors that may change drug exposure in humans, and to summarize the clinical context for appropriate use of the drug.

METHODS

A PubMed, Google Scholar, and Cross Reference search was done using the key words and combined searches: drug-drug interaction, gastroparesis, metoclopramide, natural history, pharmacokinetics, pharmacodynamics, drug-drug interaction, outcome, risk factors, tardive dyskinesia.

KEY RESULTS

Data show that the risk of tardive dyskinesia from metoclopramide is low, in the range of 0.1% per 1000 patient years. This is far below a previously estimated 1%-10% risk suggested in treatment guidelines by regulatory authorities. High-risk groups are elderly females, diabetics, patients with liver or kidney failure, and patients with concomitant antipsychotic drug therapy, which reduces the threshold for neurological complications.

CONCLUSIONS & INFERENCES

The risk of tardive dyskinesia due to metoclopramide is far below approximated numbers in treatment guidelines. This risk and the influence of known risk factors should be considered when starting a course of metoclopramide for treatment of gastroparesis.

Indirect treatment comparison of valbenazine and deutetrabenazine efficacy and safety in tardive dyskinesia

Aim: Utilize the Bucher indirect treatment comparison (ITC) method to compare valbenazine and deutetrabenazine efficacy using clinical trial data. Methods: Outcomes included mean change from baseline in Abnormal Involuntary Movement Scale (AIMS) total score, AIMS response (≥50% improvement), clinical global impression of change response (score ≤2) and safety outcomes. Data were pooled by trial and dose; outcomes were analyzed at multiple time points. Results: ITC of AIMS score improvement significantly favored valbenazine 80 mg/day at 6 weeks versus deutetrabenazine 36 mg/day at 8 weeks, while valbenazine 40 mg/day was statistically similar to all doses of deutetrabenazine at all time points. No significant differences between drugs were found in AIMS and clinical global impression of change responses and safety outcomes. Conclusion: In this ITC of pooled trial data, valbenazine was generally favorable over deutetrabenazine, although dose titration and equivalency should be considered when interpreting results.

Olanzapine: Psychopharmacology, Clinical Efficacy, and Adverse Effects

Olanzapine is an atypical antipsychotic that has a pharmacological profile similar that of clozapine. It is biotransformed by hepatic enzymes and can be dosed on a once-daily basis. In large, double-blind, placebo-controlled trials, olanzapine was shown to be efficacious in the treatment of schizophrenia relative to placebo. Many trials showed superior efficacy to haloperidol, especially against negative symptoms. Olanzapine is FDA-approved for the treatment of psychotic disorders, though data suggest possible use in depression, bipolar disorder, psychogenic polydipsia, and developmental disabilities. Olanzap-ine appears to be well-tolerated. Commonly reported adverse effects include orthostatic hypotension, sedation, hepatic transaminase elevations, weight gain, headache, agitation, dizziness, and constipation. The incidence of extrapyramidal symptoms and tardive dyskinesia is low. Few drug interactions have been reported. The recommended starting dose is 10 mg once daily. One trial indicated that the higher cost of this agent might be offset by a reduction in overall hospitalization costs.

Successful Management of Tardive Dyskinesia with Quetiapine and Clonazepam in a Patient of Schizophrenia with Type 2 Diabetes Mellitus

Tardive dyskinesia is one of the most significant side effects of antipsychotic medications. Antipsychotic treated schizophrenia patients with diabetes mellitus are more likely to develop tardive dyskinesia than those without diabetes. Clozapine is probably best supported for management of tardive dyskinesia. But clozapine has been strongly linked to hyperglycaemia and impaired glucose tolerance, so it is not preferred in patients with diabetes mellitus. We present a case of 35-year-old male with a diagnosis of schizophrenia and type 2 diabetes mellitus with tardive dyskinesia, who was successfully treated with quetiapine and clonazepam.

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.

Drug-induced movement disorders

Movement disorders are frequently a result of prescription drugs or of illicit drug use. This article focuses on prescribed drugs but briefly mentions drugs of abuse. The main emphasis is on movement disorders caused by dopamine receptor-blocking agents. However, movement disorders caused by other drugs are also briefly discussed.

Pyridoxal 5 phosphate for neuroleptic-induced tardive dyskinesia

BACKGROUND

Tardive dyskinesia is a chronic and disabling abnormal movement disorder affecting the muscles of the face, neck, tongue and the limbs. It is a common side effect of long-term antipsychotic medication use in individuals with schizophrenia and other related psychotic disorders. While there are no known effective treatments for tardive dyskinesia to date, some reports suggest that pyridoxal 5 phosphate may be effective in reducing the severity of tardive dyskinesia symptoms.

OBJECTIVES

To determine the effectiveness of pyridoxal 5 phosphate (vitamin B6 or Pyridoxine or Pyridoxal phosphate) in the treatment of neuroleptic-induced tardive dyskinesia among people with schizophrenia and other related psychotic disorders.

SEARCH METHODS

The Cochrane schizophrenia group's register of clinical trials was searched (January 2013) using the phrase: [*Pyridoxal* OR *Pyridoxine* OR *P5P* OR *PLP* OR *tardoxal* OR *Vitamin B6* O *Vitamin B 6* R in title, abstract or index terms of REFERENCE, or interventions of STUDY. References of relevant identified studies were handsearched and where necessary, the first authors of relevant studies were contacted.

SELECTION CRITERIA

Studies described as randomised controlled trials comparing the effectiveness pyridoxal 5 phosphate with placebo in the treatment of neuroleptic-induced tardive dyskinesia among patients with schizophrenia.

DATA COLLECTION AND ANALYSIS

The review authors independently extracted data from each selected study. For dichotomous data, we calculated risk ratios (RR) and their 95% confidence intervals (CIs) on an intention-to-treat basis based on a fixed-effect model. For continuous data, we calculated mean differences (MD) with 95% CIs, again based on a fixed-effect model. We assessed risk of bias for each included study and used GRADE (Grading of Recommendations Assessment, Development and Evaluation) approach to rate quality of evidence.

MAIN RESULTS

Of the 12 records retrieved by the search, three trials published in 2001, 2003 and 2007, involving 80 inpatients with schizophrenia, aged 18 to 71 years, admitted in a psychiatric facility and followed up for a period nine weeks to 26 weeks, were included. Overall, pyridoxal 5 phosphate produced a significant improvement in tardive dyskinesia symptoms when compared with placebo, assessed by a change in Extrapyramidal Symptoms Rating Scale (ESRS) scores from baseline to the end of the first phase of the included studies (2 RCTs n = 65, RR 19.97, CI 2.87 to 139.19, low quality evidence). The endpoint tardive dyskinesia score (a measure of its severity) assessed with the ESRS, was significantly lower among participants on pyridoxal 5 phosphate compared to those on placebo (2 RCTs n = 60, MD -4.07, CI -6.36 to -1.79, low quality evidence).It was unclear whether pyridoxal 5 phosphate led to more side effects (n = 65, 2 RCTs, RR 3.97, CI 0.20 to 78.59, low quality evidence) or caused deterioration in tardive dyskinesia symptoms when compared to placebo (n = 65, 2 RCTs, RR 0.16, CI 0.01 to 3.14, low quality evidence). Five participants taking pyridoxal 5 phosphate withdrew from the study because they were not willing to take more medications while none of the participants taking placebo discontinued their medications (n = 65, 2 RCTs, RR 8.72, CI 0.51 to 149.75, low quality evidence).There was no significant difference in the endpoint positive and negative psychiatric symptoms scores, measured using the Positive and Negative symptoms Scale (PANSS) between participants taking pyridoxal 5 phosphate and those taking placebo. For the positive symptoms: (n = 15, 1 RCT, MD -1.50, CI -4.80 to 1.80, low quality evidence). For negative the symptoms: (n = 15, 1 RCT, MD -1.10, CI -5.92 to 3.72, low quality evidence).

AUTHORS' CONCLUSIONS

Pyridoxal 5 phosphate may have some benefits in reducing the severity of tardive dyskinesia symptoms among individuals with schizophrenia. However, the quality of evidence supporting the effectiveness of pyridoxal 5 phosphate in treating tardive dyskinesia is low, based on few studies, short follow-up periods, small sample sizes and inadequate adherence to standardised reporting guidelines for randomised controlled trials among the included studies.

Tardive dyskinesia: therapeutic options for an increasingly common disorder

Tardive dyskinesia (TD) is a serious, often disabling, movement disorder that is caused by medications that block dopamine receptors (i.e., neuroleptics, anti-emetics). There is currently no standard treatment approach for physicians confronted with such patients. This may be the result of notions that TD is disappearing because of the switch to second-generation antipsychotic agents and that it is largely reversible. In this article we demonstrate that second-generation antipsychotics do, indeed, cause TD and, in fact, the frequency is likely higher than expected because of growing off-label uses and a tripling of prescriptions written in the last 10 years. In addition, studies demonstrate that TD actually remits in only a minority of patients when these drugs are withdrawn. Furthermore, neuroleptic agents are often utilized to treat TD, despite prolonged exposure being a risk factor for irreversibility. The outcome of these trends is a growing population afflicted with TD. We review non-neuroleptic agents that have shown positive results in small, early-phase, blinded trials, including tetrabenazine, amantadine, levetiracetam, piracetam, clonazepam, propranolol, vitamin B6, and Ginkgo biloba. Other options, such as botulinum toxin and deep brain stimulation, will also be discussed, and a suggested treatment algorithm is provided. While these agents are reasonable treatment options at this time there is a need, with a concerted effort between neurology and psychiatry, for full-scale drug development, including multicenter, randomized, blinded trials to confirm the effectiveness of the agents that were positive in phase 2 trials and the development of newer ones.

Tardive and spontaneous dyskinesia incidence in the general population

BACKGROUND

To identify the incidence rate of spontaneous dyskinesia (SD) and tardive dyskinesia (TD) in a general population and to examine the association between dykinesia and potential risk factors (exposure to metoclopramide [MCP], antipsychotic drugs, and history of diabetes and psychoses).

METHODS

A retrospective cohort study was conducted for the years 2001 through 2010, based on medical claims data from the Deseret Mutual Benefit Administrators (DMBA).

RESULTS

Thirty-four cases of TD and 229 cases of SD were identified. The incidence rate of TD among persons previously prescribed an antipsychotic or metoclopramide (MCP) (per 1,000) was 4.6 (1.6-7.7) for those with antipsychotic drug use only, 8.5 (4.8-12.2) for those with MCP use only, and 15.0 (2.0-28.1) for those with both antipsychotic and MCP use. In the general population, the incidence rate (per 100,000 person-years) of TD was 4.3 and of probable SD was 28.7. The incidence rates of TD and SD increased with age and were greater for females. Those with diabetes or psychoses had almost a 3-fold greater risk of TD than those without either of these diseases. Persons with schizophrenia had 31.2 times increased risk of TD than those without the disease. Positive associations also existed between the selected diseases and the incidence rate of probable SD, with persons with schizophrenia having 4.4 times greater risk of SD than those without the disease.

CONCLUSIONS

SD and TD are rare in this general population. Diabetes, psychoses, and especially schizophrenia are positively associated with SD and TD. A higher proportion of those with SD present with spasm of the eyelid muscles (blepharospasm) compared more with the TD cases who present more with orofacial muscular problems.

Movement disorders in patients with diabetes mellitus

Movement disorders are not infrequent in patients with diabetes mellitus. These may occur on the basis of both central and peripheral nervous system dysfunction and can be secondary to severe hyperglycemia, complications of diabetes or its treatment and less often to diseases in which both diabetes and a movement disorder are primary manifestations of the same underlying disease. We present a typical case of a severe movement disorder complicating diabetes as a springboard to review the spectrum of disorders associated with this condition.

Tardive dyskinesia

OPINION STATEMENT

Tardive dyskinesia (TD) is iatrogenic (drug-induced); hence the best strategy is prevention. Try to limit exposure to any dopamine receptor blocking agents (DRBAs) if possible. These agents may be unavoidable in some psychiatric conditions such as schizophrenia, but alternative therapies can be used in many situations, such as in the treatment of depression, anxiety, gastrointestinal conditions, and other neurologic conditions, including migraines and sleep disorders. When DRBAs are necessary, physicians should prescribe the smallest possible dose and try to taper and stop the drug at the earliest signs of TD. Abrupt cessation should be avoided, as this can worsen symptoms of TD. Always discuss and document the possibility of TD as an adverse effect when starting patients on DRBAs. If TD is mild and tolerable, the withdrawal of the offending agent is possible, and exposure to DRBAs was short, physicians should consider avoiding treatment and waiting for spontaneous recovery. When treatment is necessary, tetrabenazine (TBZ) is considered a potential first-line agent and is known to be one of the most effective drugs in treating TD, but it is expensive and adverse effects such as depression, akathisia and parkinsonism frequently occur. Therefore, second-line agents with better tolerability profiles are often tried first in practice. These include amantadine, benzodiazepines, beta-blockers, and levetiracetam. When using TBZ, adverse effects should be aggressively monitored. (Depression often can be managed with antidepressants, for instance). In patients with psychosis, withdrawal of the antipsychotic may not be possible. Switching to clozapine or quetiapine is one option to minimize TD. When these agents are contraindicated and the patient must continue using other atypical antipsychotic drugs, try to add dopamine-depleting agents such as TBZ or reserpine, but watch for the development of parkinsonism. When the symptoms are focal, such as tongue protrusion or blepharospasm, botulinum toxin injections can be very effective if spontaneous recovery does not occur. As a last resort, when disabling, life-threatening symptoms of TD persist despite all of the above-mentioned methods, some advocate resuming treatment with the DRBA to suppress symptoms of TD. This has the potential to worsen TD in the long run.

Review article: metoclopramide and tardive dyskinesia

BACKGROUND

Metoclopramide is a dopamine receptor antagonist which has been used for treatment of a variety of gastrointestinal symptoms over the last thirty years. In 2009, the FDA issued a black box warning regarding long-term or high-dose use of this medication because of the risk of developing tardive dyskinesia.

AIMS

To review the mechanism of action and pharmacokinetic properties of metoclopramide, the risk of metoclopramide-induced tardive dyskinesia, potential mechanisms that may alter and to summarize the clinical context for appropriate use of the drug.

METHODS

We conducted a PubMed search using the following key words and combined searches: metoclopramide, neuroleptics, tardive dyskinesia, incidence, prevalence, dopamine, receptors, pharmacokinetic, pharmacology, pharmacogenetics, DRD3 Ser9Gly polymorphism, cytochrome P450, p-glycoprotein, risk factors, gastroparesis, outcome, natural history.

RESULTS

Available data show that risk of tardive dyskinesia from metoclopramide use is likely to be <1%, much less than the estimated 1-10% risk previously suggested in national guidelines. Tardive dyskinesia may represent an idiosyncratic response to metoclopramide; pharmacogenetics affect pharmacokinetic and dopamine receptor pharmacodynamics in response to neuroleptic agents that cause similar neurological complications.

CONCLUSION

Community prevalence and pharmacogenetic mechanisms involved in metoclopramide-induced tardive dyskinesia require further study to define the benefit-risk ratio more clearly.

NonParkinsonism Movement Disorders in the Elderly

OBJECTIVE

The primary objective of this article is to review the clinical presentation and pharmacologic management of essential tremor and tardive dyskinesia.

DATA SOURCES

The MEDLINE (1966-August 2005), Cochrane Database of Systematic Reviews, and International Pharmaceutical Abstracts (1970-August 2005) databases were searched for original research and review articles published in English. The search terms were essential tremor and tardive dyskinesia. Reference lists from articles were also consulted.

DATA SYNTHESIS

Essential tremor is most commonly manifested as a postural or action tremor of the upper extremities. Midline regions such as the head and voice are also commonly affected. Based on review of the literature, propranolol and primidone are the current pharmacologic mainstays for treating essential tremor of the upper extremities. The choice of agent depends on patient-specific factors such as underlying medical conditions. Other agents with demonstrated efficacy include gabapentin and topiramate. Benzodiazepines are effective adjunctive agents, but should be utilized judiciously in the elderly. Botulinum toxin is effective for essential tremor of the voice and head. Surgery is very effective, but may not be appropriate in the frail elderly and should be avoided in the presence of cognitive impairment. Tardive dyskinesia is characterized by involuntary choreoathetoid movements of the orofacial region. For the management of tardive dyskinesia, emphasis is placed on primary prevention and early recognition of signs and symptoms. In some cases, discontinuation of the offending agent can result in reversal of symptoms. If a conventional neuroleptic is the causative agent, switching to an atypical antipsychotic may be helpful. Overall, few treatments have proven to be consistently useful. Other agents that may be helpful include acetylcholinesterase inhibitors, amantadine, baclofen, benzodiazepines, branched chain amino acids, gabapentin, levetiracetam, pyridoxine, verapamil, and vitamin E.

CONCLUSION

Current pharmacologic agents for essential tremor can be expected to provide partial benefit. However, agents for the symptomatic management of tardive dyskinesia are limited, and additional research is warranted in this area.

Diabetes mellitus and drug-induced Parkinsonism: a case-control study

To investigate if diabetes is more common in drug-induced parkinsonism patients. We performed a hospital-based retrospective case-control study on 44 drug-induced parkinsonism (DIP) patients, 177 Parkinson disease patients, and 176 acute stroke patients matched for age and sex who were seen over the same period at the same hospital. The frequency of diabetes, age-at onset and sex were compared between DIP and IPD or acute stroke. Multivariate analysis showed that patients with diabetes are more frequent in DIP compared with IPD (p<0.001, adjusted OR 5.48; 95% CI, 2.52-11.94). The frequency of diabetes in DIP was comparable to that in acute stroke patients (p=0.16, adjusted OR 0.62; 95% CI, 0.32-1.21). These data suggest that diabetes may be a risk factor for DIP. Drugs with dopamine receptor blocking potency should be avoided in elderly with diabetes.

Mortality rates among patients with schizophrenia and tardive dyskinesia

Tardive dyskinesia (TD) is a severe and potentially irreversible movement, and previous studies have suggested increased mortality among patients with TD, but most of these studies are limited by small sample sizes and short periods of follow-up. This study examined the mortality rate of a cohort of 608 Asian patients with schizophrenia during a 6-year period and used survival analyses on time from case ascertainment to outcome (death). Data on the survival status were collected and compared between those with and without TD, and cross-tabulation was performed to show the correlation between survival and mortality rates among patients with and without TD.Seventy-two patients died, 39 (54.2%) of whom had TD previously. Of the 536 surviving cases, 239 (44.6%) have TD. The mortality rates between those with TD and those without TD were statistically significant (hazard ratio, 2.62; 95% confidence interval, 1.58-4.33; P = 0.0006).The mortality rate was dependent on age; nevertheless, the adverse effect of TD on survival rate, although reduced, remains after controlling for age (hazard ratio, 1.90; 95% confidence interval, 1.12-3.20; P = 0.017). Our finding showed a robust association with increased mortality rate and TD, but we failed to find any significant association with any specific cause of death and TD.

Neurophysiological endophenotypes across bipolar and schizophrenia psychosis

The search for liability genes of the world's 2 major psychotic disorders, schizophrenia and bipolar disorder I (BP-I), has been extremely difficult even though evidence suggests that both are highly heritable. This difficulty is due to the complex and multifactorial nature of these disorders. They encompass several intermediate phenotypes, some overlapping across the 2 psychotic disorders that jointly and/or interactively produce the clinical manifestations. Research of the past few decades has identified several neurophysiological deficits in schizophrenia that frequently occur before the onset of psychosis. These include abnormalities in smooth pursuit eye movements, P50 sensory gating, prepulse inhibition, P300, mismatch negativity, and neural synchrony. Evidence suggests that many of these physiological deficits are distinct from each other. They are stable, mostly independent of symptom state and medications (with some exceptions) and are also observed in non-ill relatives. This suggests a familial and perhaps genetic nature. Some deficits are also observed in the BP-I probands and to a lesser extent their relatives. These deficits in physiological measures may represent the intermediate phenotypes that index small effects of genes (and/or environmental factors). The use of these measures in genetic studies may help the hunt for psychosis liability genes and clarify the extent to which the 2 major psychotic disorders share etio-pathophysiology. In spite of the rich body of work describing these neurophysiological measures in psychotic disorders, challenges remain: Many of the neurophysiological phenotypes are still relatively complex and are associated with low heritability estimates. Further refinement of these physiological phenotypes is needed that could identify specific underlying physiological deficits and thereby improve their heritability estimates. The extent to which these neurophysiological deficits are unique or overlap across BP-I and schizophrenia is unclear. And finally, the clinical and functional consequences of the neurophysiological deficits both in the probands and their relatives are not well described.

Tardive dyskinesia and glucid metabolism

A role of insulin-dependent diabetes in the onset of tardive dyskinesia has been reported and relies on weak physiopathological evidence.

OBJECTIVE

To study the relationship between the occurrence of tardive dyskinesia and variations in glucose levels in a population of patients under typical antipsychotic treatment.

METHODS

Sixty-nine patients with a schizophrenic disorder and who had been receiving continuous neuroleptic treatment for at least 2 years were included. Tardive dyskinesias were assessed by the Abnormal Involuntary Movements Scale (AIMS) and glucose levels by glucose oxidase method.

RESULTS

No significant differences in values of fasting glucose (FG) levels, post-prandial glucose (PPG) levels and glycosylated haemoglobin between the groups with and without tardive dyskinesia were found. In the sub-group with normal FG, comparison of post-prandial delta glucose levels (difference between PPG and FG) between the two group with and without tardive dyskinesia showed a significant difference (p < 0.05). This comparison also showed a correlation between post-prandial delta glucose levels and the AIMS score in the group with tardive dyskinesia (r = 0.482, p < 0.05).

CONCLUSION

Glucose metabolism could be involved in patients with tardive dyskinesia. Various factors outside antipsychotic treatment can favour a disturbance of glucose metabolism, which may not be severe.

Implications of the CATIE trial on treatment: extrapyramidal symptoms

Development of extrapyramidal symptoms (EPS), particularly tardive dyskinesia (TD), has long been a troubling side effect for patients taking antipsychotics. Atypical antipsychotics have been hailed as an improvement over conventional antipsychotics, offering similar efficacy with more favorable EPS profiles. In the recent Clinical Antipsychotic Trials of Intervention Effectiveness (CATIE) study, which compared the conventional antipsychotic perphenazine with atypical antipsychotics olanzapine, quetiapine, risperidone, and ziprasidone in patients with schizophrenia, no significant differences in time to treatment discontinuation due to intolerability were observed between treatment groups. However, perphenazine was associated with a higher rate of patients experiencing EPS as well as a significantly higher rate of discontinuation due to EPS, despite the fact that patients with TD at baseline were excluded from the perphenazine group. Unfortunately, due to short treatment duration, the CATIE study did not have the assay sensitivity to detect differences in TD risk among any of the drugs. Thus, the atypical antipsychotics remain the first line of treatment for most patients, with specific drug selection based on benefit-risk profiles that best fit the individual patient's needs. Frequent monitoring, while noting a patient's subjective experience, remains the best strategy for choosing therapy to maximize symptom relief and minimize the impact of EPS and other side effects over the long- term. This article explores the reported results of the CATIE trial regarding EPS and emphasizes the differentiation of the atypicals from perphenazine on EPS and how these results should be incorporated into daily practice for the clinician.

Focus on lower risk of tardive dyskinesia with atypical antipsychotics

BACKGROUND

Tardive dyskinesia (TD) is one of the most serious iatrogenic neurological complications of the first-generation antipsychotics. Identifying the risk factors for TD is important to minimize the risk of this potentially irreversible movement disorder in susceptible populations.

METHODS

A Medline search was conducted for the literature on risk factors for TD with the first-generation antipsychotics, as well as the emerging literature of the lower risk of TD with the second-generation antipsychotics.

RESULTS

Several demographic, phenomenological, comorbidities and treatment variables have been reported to be associated with higher risk of TD. On the other hand, significantly lower rates of TD have been reported with the second-generation atypical antipsychotics, even in high risk groups such as the elderly.

CONCLUSIONS

The use of the second-generation antipsychotics as first-line treatment of psychosis appears to have lowered the overall prevalence of acute movement disorders as well as TD, and have led them to become the standard of care in part because of their safer extrapyramidal profiles.

Clinical correlates of tardive dyskinesia in schizophrenia: baseline data from the CATIE schizophrenia trial

OBJECTIVE

To examine the clinical characteristics of individuals with schizophrenia that develop tardive dyskinesia (TD) associated with antipsychotic treatment.

METHODS

Baseline data on 1460 patients with schizophrenia were collected as part of the Clinical Antipsychotic Trials of Intervention Effectiveness schizophrenia study. Subjects who met Schooler-Kane criteria for probable TD were compared to those without TD. Multiple regression analyses were used to examine the relationship between TD and clinical variables.

RESULTS

212 subjects met the Schooler-Kane criteria for probable TD and 1098 had no history or current evidence of TD. Subjects with TD were older, had a longer duration of receiving antipsychotic medication, and were more likely to have been receiving a conventional antipsychotic and an anticholinergic agent. After controlling for important baseline covariates, diabetes mellitus (DM) and hypertension did not predict TD, whereas substance abuse significantly predicted TD. Differences in cognitive functioning were not significantly different after controlling for baseline covariates. The TD subjects also had higher ratings of psychopathology, EPSE, and akathisia.

CONCLUSION

Our results confirm the established relationships between the presence of TD and age, duration of treatment with antipsychotics, treatment with a conventional antipsychotic, treatment with anticholinergics, the presence of EPS and akathisia, and substance abuse. Subjects with TD had higher ratings of psychopathology as measured by the PANSS. We found no support for DM or hypertension increasing the risk of TD, or for TD being associated with cognitive impairment.

Diabetes, tardive dyskinesia, parkinsonism, and akathisia in schizophrenia: a retrospective study applying 1998 diabetes health care guidelines to antipsychotic use

BACKGROUND

This study examines the links among diabetes, tardive dyskinesia (TD), and other extrapyramidal symptoms (EPS) in schizophrenia outpatients treated with typical and atypical antipsychotics.

OBJECTIVES

Using a retrospective chart review, we compared 30 schizophrenia patients with diabetes mellitus (DM) with 30 schizophrenia patients, matched for age and sex, with no DM. We compared prevalence and severity of parkinsonism, akathisia, TD, dystonia, and antipsychotic type (that is, typical vs atypical).

RESULTS

We found no statistically significant differences between the DM group and the non-DM group prevalence and severity of EPS, including TD.

CONCLUSION

We did not find DM and TD association to be significant in the era of atypical antipsychotics, possibly because of their antidyskinetic effect.

Chronic metoclopramide therapy for diabetic gastroparesis

OBJECTIVE

To review the safety and efficacy of chronic metoclopramide for diabetic gastroparesis.

DATA SOURCES

Medical literature was accessed through MEDLINE (1965 to October 2002) and PubMed (1965 to October 2002). Key search terms included metoclopramide; diabetic gastroparesis; and dyskinesia, drug induced.

DATA SYNTHESIS

Metoclopramide is often used for diabetic gastroparesis, despite the risk of tardive dyskinesia. Published information is limited regarding long-term efficacy and toxicity of metoclopramide. The literature was assessed concerning these topics.

CONCLUSIONS

Limited data do not provide sufficient evidence to conclude whether metoclopramide is efficacious for chronic use. Routine monitoring may mitigate the risk associated with metoclopramide therapy.

Miscellaneous treatments for neuroleptic-induced tardive dyskinesia

BACKGROUND

Tardive dyskinesia is a disabling movement disorder associated with the prolonged use of neuroleptic medication. This review, one in a series examining the treatment of tardive dyskinesia, will cover miscellaneous treatments not covered elsewhere.

OBJECTIVES

To determine whether the following interventions were associated with a reduction of neuroleptic induced tardive dyskinesia: botulin toxin, endorphin, essential fatty acid, EX11582A, ganglioside, insulin, lithium, naloxone, oestrogen, periactin, phenylalanine, piracetam, stepholidine, tryptophan, neurosurgery, or ECT.

SEARCH STRATEGY

The initial search of Biological Abstracts (1982-1995), The Cochrane Schizophrenia Group's Register (January 1996), EMBASE (1980-1995), LILACS (1982-1996), MEDLINE (1966-1995) and PsycLIT (1974-1995) was updated by searching Cochrane Schizophrenia Group's Register in July 2002. References of all relevant studies were searched for further trial citations. Principal authors of trials were contacted.

SELECTION CRITERIA

Studies were selected if they focused on people with schizophrenia or other chronic mental illnesses, with neuroleptic-induced tardive dyskinesia and compared the use of the interventions listed above versus placebo or no intervention.

DATA COLLECTION AND ANALYSIS

Studies were reliably selected, quality assessed and data extracted. Data were excluded where more than 50% of participants in any group were lost to follow up. For binary outcomes a random effects risk ratio (RR) and its 95% confidence interval (CI) was calculated. Where possible, the weighted number needed to treat/harm statistic (NNT/H), and its 95% confidence interval (CI), was also calculated. For continuous outcomes, endpoint data were preferred to change data. Non-skewed data from valid scales were to have been synthesised using a weighted mean difference (WMD).

MAIN RESULTS

Fifty-seven references describing 37 different trials were identified by the search strategy. Seven of these were included, 27 excluded, and three await assessment. Ceruletide was not clearly more effective than placebo (n=132, 2 RCTs, RR not any improvement in tardive dyskinesia 0.82 CI 0.6 to 1.1). This also applied to gamma-linolenic acid, although data were sparse (n=16, 1 RCT, RR no clinical improvement 1.00 CI 0.7 to 1.5), oestrogen (n=12, 1 RCT, RR no clinically important improvement 1.2 CI 0.8 to 1.7), and lithium (n=11, 1 RCT, RR no clinically important improvement 1.39 CI 0.6 to 3.1). Phenylalanine may even be detrimental (n=18, 1 RCT, MD AIMS score 4.40 CI 1.16 to 7.64). One small study (n=20) found that insulin was more likely to produce a clinical improvement in tardive dyskinesia than placebo (RR no clinical improvement 0.5 CI 0.3 to 0.9, NNT 2 CI 1 to 5).

REVIEWER'S CONCLUSIONS

There is no strong evidence to support the everyday use of any of the agents included in this review. All results must be considered inconclusive and these compounds probably should only be used within the context of a well-designed evaluative study.

Role of oxidative stress and antioxidants in neurodegenerative diseases

Neurodegenerative diseases (NDD) are a group of illness with diverse clinical importance and etiologies. NDD include motor neuron disease such as amyotrophic lateral sclerosis (ALS), cerebellar disorders, Parkinson's disease (PD), Huntington's disease (HD), cortical destructive Alzheimer's disease (AD) and Schizophrenia. Numerous epidemiological and experimental studies provide many risk factors such as advanced age, genetic defects, abnormalities of antioxidant enzymes, excitotoxicity, cytoskeletal abnormalities, autoimmunity, mineral deficiencies, oxidative stress, metabolic toxicity, hypertension and other vascular disorders. Growing body of evidence implicates free radical toxicity, radical induced mutations and oxidative enzyme impairment and mitochondrial dysfunction due to congenital genetic defects in clinical manifestations of NDD. Accumulation of oxidative damage in neurons either primarily or secondarily may account for the increased incidence of NDD such as AD, ALS and stroke in aged populations. The molecular mechanisms of neuronal degeneration remain largely unknown and effective therapies are not currently available. Recent interest has focused on antioxidants such as carotenoids and in particular lycopene, a potent antioxidant in tomatoes and tomato products, flavonoids and vitamins as potentially useful agents in the management of human NDD. The pathobiology of neurodegenerative disorders with emphasis on genetic origin and its correlation with oxidative stress of neurodegenerative disorders will be reviewed and the reasons as to why brain constitutes a vulnerable site of oxidative damage will be discussed. The article will also discuss the potential free radical scavenger, mechanism of antioxidant action of lycopene and the need for the use of antioxidants in the prevention of NDD.

Tardive dyskinesia and impaired glucose tolerance

The authors examined the role of impaired glucose metabolism in the pathophysiology of tardive dyskinesia in schizophrenic patients with and without persistent TD. Glucose tolerance and insulin levels were determined in 86 patients with persistent tardive dyskinesia and in 108 patients without tardive dyskinesia. Dyskinesias were assessed by the abnormal involuntary movement scale (AIMS) and extrapyramidal symptoms by the Simpson--Angus rating scale (SARS). Fasting blood glucose levels were significantly lower while the first and second hour glucose levels did not reveal any differences in patients with tardive dyskinesia compared with those without tardive dyskinesia. Insulin levels did not differ in these two groups. Our cross-sectional epidemiological study does not suggest hyperglycemia to be a risk factor for tardive dyskinesia. However, prospective long-term studies with multiple assessment points are needed to clarify the role of glucose metabolism in the development of tardive dyskinesia.

Tardive dyskinesia among Chinese and Malay patients with schizophrenia

The prevalence of tardive dyskinesia (TD) was studied with the Abnormal Involuntary Movements Scale in Chinese and Malay patients with schizophrenia who were hospitalized in a Singapore state psychiatric institute. We also studied the relationship of neuroleptic-induced extrapyramidal side effects to TD. By using established criteria, the rates of TD were 40.6% for Chinese and 29.0% for Malays, higher than previously reported for Chinese subjects. Older age and lower current neuroleptic dose were significantly associated with TD. Multivariate analysis, after controlling for other salient risk variables, did not show a significant difference in TD prevalence rates between the two races. We conclude that suggested differences in interethnic rates of TD among Chinese, Malays, and Westerners are unlikely to exist and that any variation in prevalence is more likely to be determined by differences in duration of exposure and dose levels of neuroleptic drugs.

Diabetes is not a risk factor for tardive dyskinesia: a retrospective observational study

The aim of this observational study was to compare the prevalence of tardive dyskinesia (TD) in diabetic and non diabetic patients. We compared 34 diabetic patients with 34 non diabetic controls, matched by sex, age and time of admission, who had received a complete neuropsychiatric evaluation and who had been exposed to antidopaminergic treatment for at least 3 months. Among them, 8 of 24 diabetic (33.3%) and 6 of 15 (40.0%) non diabetic patients presented TD. The prevalence of TD in the diabetic group is numerically lower than in the controls but the difference is not statistically significant (chi(2) = 0.006; fd = 1; p = 0.937). These results suggest that diabetes is unlikely to play a major role in the pathogenesis of TD.

Long-term effects of topiramate on bipolar mood instability, weight change and glycemic control: a case-series

Topiramate is an antiepileptic agent, which is being investigated as a mood-stabilizer. Three obese individuals with DSM-IV bipolar I disorder and type II diabetes mellitus received topiramate treatment in combination with antipsychotics and valproate or carbamazepine. In addition to improved mood stability, these individuals lost between 16 to 20.5% of their pre-topiramate body weight and also achieved significant glycemic control.

Movement disorder, memory, psychiatric symptoms and serum DHEA levels in schizophrenic and schizoaffective patients

OBJECTIVE

Reports of low levels of dehydroepiandrosterone (DHEA) or its sulphate (DHEA-S) in some schizophrenic patients and in some persons with poorer motoric and cognitive functioning led us to examine clinical correlates of serum DHEA and DHEA-S levels in schizophrenic patients.

METHOD

Ratings of abnormal movements, memory and psychiatric symptoms in 17 medicated chronic schizophrenic or schizoaffective inpatients at a state hospital were correlated with serum DHEA and DHEA-S levels, and their ratios with serum cortisol.

RESULTS

Controlling for age, higher DHEA levels and/or higher DHEA/cortisol ratios were significantly correlated with lower symptom ratings on the Brief Psychiatric Rating Scale, better performance on some measures of memory, and lower ratings of parkinsonian symptoms.

CONCLUSION

Relatively low DHEA levels or DHEA/cortisol ratios may identify a particularly impaired subgroup of medicated patients with chronic schizophrenia. Potential implications are discussed.

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.

Managing antipsychotic-induced acute and tardive dystonia

Antipsychotic-induced extrapyramidal adverse effects continue to be a serious problem in the treatment of psychotic disorders. While the pathophysiology of these adverse effects is not well understood, much recent research has focused on improving our ability to use available pharmacotherapy in the most effective and least toxic manner. Acute dystonic reactions only occur within the first days of antipsychotic treatment. They are often distressing and frightening for the patient and may even be dangerous. However, they can be effectively prevented or reversed with anticholinergics. Furthermore, the growing use of the new atypical antipsychotics will lead to a significant decrease in the rate of acute dystonic reactions. In contrast, tardive dystonia is a long-lasting menace in the course of antipsychotic treatment, for which there is no established therapy. Tardive dystonia is sometimes disabling or disfiguring and, like other tardive disorders, is potentially irreversible. Because, in most cases, patients need to continue taking the antipsychotic that has caused the adverse effect to prevent relapse of the mental illness, preventive measures are crucial. Antipsychotics should be prescribed only for patients affected by psychotic disorders, when definitely indicated and at the lowest effective dosage. The use of clozapine and other novel antipsychotic agents is also likely to represent an important step in the prevention and treatment of tardive dystonia. Compared with traditional antipsychotics, most of the new antipsychotics are characterised by a low acute extrapyramidal adverse effects liability and they also bring the hope of reducing the risk of tardive disorders. If tardive dystonia has occurred, switching to clozapine or another atypical antipsychotic and treatment with tetrabenazine, reserpine and botulinum toxin are possible options.

New strategies for old problems: tardive dyskinesia (TD). Review and report on severe TD cases treated with clozapine, with 12, 8 and 5 years of video follow-up

Tardive dyskinesia (TD) is the most feared and troublesome extrapyramidal side-effect of prolonged neuroleptic (NL) treatment. We present a review of TD. Its pathophysiology remains elusive, although extrapyramidal symptoms (EPS) increase the liability for TD. Nowadays, therefore, avoidance of all EPS remains the best preventive strategy, as it is not possible to predict which liable patients will develop TD, or of what type or severity. TD frequently includes dystonic features, and is more disabling when these dystonias are present. Clozapine (CLZ) has been reported to be effective in suppressing nearly 60% of TD syndromes, specially those with dystonic features. Based on the few reports in the literature on CLZ and TD by the early 1980s, we started to videotape the first severe TD patient treated with CLZ in 1984. We present the first three case reports of severe TD, with prominent disabling dystonic features, treated with CLZ and videotaped since pretreatment and then periodically for 12, 8 and 5 years of follow-up, respectively. The patients' current diagnosis, gender and age are: Case 1, DSM-IV Schizophrenia Residual Type, male, 39 years; Case 2, DSM-IV Polysubstance Related Disorder, Borderline Personality Disorder, female, 28 years; Case 3, DSM-IV Schizoaffective Disorder, male, 40 years. Two of them presented with a recurrence of TD because of CLZ interruption within the first 2 months of treatment, with no further breakthrough to date. The first two cases have complete remission of TD; the third case is still improving after 5 years of CLZ treatment, with only minor dystonic features persisting that constitute no impairment for work or daily routines at present. All patients, independent of their psychiatric primary diagnosis, have shown significant and progressive improvement in both motor and psychosocial aspects. None of them has been rehospitalized. Long-term treatment and follow-up is required to avoid TD recurrence and to assure full assessment of treatment effectiveness. Ideally, periodic video recording with standardized examination is advisable for long-term follow-up and outcome assessment. At present, CLZ could be regarded as the drug of choice for patients with TD, specially for those with disabling and or dystonic features and who require ongoing NL therapy. The use of novel antipsychotic agents for TD treatment and prevention, with their low EPS liability, is promising, but has yet to be tested.

Increased S(-)-apomorphine-induced vacuous chewing and attenuated effect of chronic haloperidol treatment in streptozotocin-induced diabetic rat

The incidence of S(-)-apomorphine-induced vacuous chewing movements (VCMs) as a model for tardive dyskinesia was investigated in streptozotocin (STZ)-induced diabetic rats. A single dose of STZ (65 mg/kg, intravenously) caused a diabetic state (hyperglycemia, 480-490 vs. 116-118 mg/dl in naive rats). S(-)-apomorphine (250 micrograms/kg, subcutaneously)-induced VCMs were significantly intensified in diabetic rats which had received STZ 9 weeks previously. The enhancement of VCMs was also observed in nondiabetic rats which received subsequent treatment with depot haloperidol (4 mg/kg, intramuscularly, once a week, every week for 4 weeks) followed by a 2-week washout period. The ability of haloperidol to enhance VCMs was attenuated in diabetic rats. The implications of these results in relation to altered neurotransmissions in STZ-induced diabetes are discussed.

Risk factors for orofacial and limbtruncal tardive dyskinesia in older patients: a prospective longitudinal study

Although there is a consensus that orofacial and limbtruncal subtypes of tardive dyskinesia (TD) exist and may represent distinct pathophysiologic entities, few studies have examined the incidence of and risk factors associated with the development of these TD subtypes. Two hundred and sixty-six middle-aged and elderly outpatients with a median duration of 21 days of total lifetime neuroleptic exposure at study entry were evaluated at 1- to 3-month intervals. Using "mild" dyskinesia in any part of the body for diagnosis of TD, the cumulative incidence of orofacial TD was 38.5 and 65.7% after 1 and 2 years, respectively, whereas that of limbtruncal TD was 18.6 and 32.6% after 1 and 2 years. Preclinical dyskinesia was predictive of both orofacial and limbtruncal TD. History of alcohol abuse or dependence was a significant predictor of orofacial TD only whereas tremor was a significant predictor of limbtruncal TD only. Findings support suggestions that orofacial and limbtruncal TD may represent specific subsyndromes with different risk factors.

Diabetes mellitus in schizophrenic patients

Studies conducted in the United States and Japan indicate that diabetes mellitus is more common among schizophrenic patients than among the general population. The prevalence of known diabetes was examined in 95 schizophrenic patients aged 45 to 74 years admitted to a long-term care facility in Italy. The overall prevalence of diabetes was 15.8% (95% confidence interval, 12.1% to 19.5%), and increased from 0% in those younger than 50 years, through 12.9% in the 50- to 59-year age group, and to 18.9% in the 60- to 69-year age group, and then decreased to 16.7% in those aged 70 to 74 years. These rates are considerably higher than those reported from population surveys in Italy, and indicate that a higher prevalence of diabetes in schizophrenic patients may be a universal phenomenon. The clinical picture indicated that in all cases this was the common variant of type II (non-insulin-dependent) diabetes mellitus. Diabetes was more common in patients not receiving neuroleptics than in those who were receiving such treatment. There was no association between diabetes and the use of anticholinergic drugs.