Treatment of tardive dyskinesia with vitamin E

Vitamin E in the treatment of tardive dyskinesia: a meta-analysis

Long-term use of antipsychotic drugs is associated with tardive dyskinesia. At present, there is no satisfactory treatment for tardive dyskinesia. Some randomized trials suggested that vitamin E can improve tardive dyskinesia. This study was undertaken to evaluate the effects of vitamin E treatment for tardive dyskinesia. We searched internet databases for randomized controlled trials. A total of 21 studies including 854 patients with tardive dyskinesia were included in this meta-analysis. Eighteen studies reported the Abnormal Involuntary Movements Scale (AIMS) as the primary outcome. After vitamin E treatment, a decrease of 2.36 (95% CI = -3.27 to -1.45; P < 0.00001) in the AIMS was observed in the treatment group, compared with the control group. Vitamin E may offer a new avenue treatment for tardive dyskinesia.

Systematic review of interventions for treating or preventing antipsychotic-induced tardive dyskinesia

BACKGROUND

Antipsychotic medication can cause tardive dyskinesia (TD) - late-onset, involuntary, repetitive movements, often involving the face and tongue. TD occurs in > 20% of adults taking antipsychotic medication (first-generation antipsychotics for > 3 months), with this proportion increasing by 5% per year among those who continue to use these drugs. The incidence of TD among those taking newer antipsychotics is not different from the rate in people who have used older-generation drugs in moderate doses. Studies of TD have previously been found to be limited, with no treatment approach shown to be effective.

OBJECTIVES

To summarise the clinical effectiveness and safety of treatments for TD by updating past Cochrane reviews with new evidence and improved methods; to undertake public consultation to gauge the importance of the topic for people living with TD/the risk of TD; and to make available all data from relevant trials.

DATA SOURCES

All relevant randomised controlled trials (RCTs) and observational studies.

REVIEW METHODS

Cochrane review methods, network meta-analysis (NMA).

DESIGN

Systematic reviews, patient and public involvement consultation and NMA.

SETTING

Any setting, inpatient or outpatient.

PARTICIPANTS

For systematic reviews, adults with TD who have been taking a stable antipsychotic drug dose for > 3 months.

INTERVENTIONS

Any, with emphasis on those relevant to UK NHS practice.

MAIN OUTCOME MEASURES

Any measure of TD, global assessments and adverse effects/events.

RESULTS

We included 112 studies (nine Cochrane reviews). Overall, risk of bias showed little sign of improvement over two decades. Taking the outcome of 'TD symptoms improved to a clinically important extent', we identified two trials investigating reduction of antipsychotic dose [n = 17, risk ratio (RR) 0.42, 95% confidence interval (CI) 0.17 to 1.04; very low quality]. Switching was investigated twice in trials that could not be combined (switching to risperidone vs. antipsychotic withdrawal: one RCT, n = 42, RR 0.45, 95% CI 0.23 to 0.89; low quality; switching to quetiapine vs. haloperidol: one RCT, n = 45, RR 0.80, 95% CI 0.52 to 1.22; low quality). In addition to RCTs, six observational studies compared antipsychotic discontinuation with decreased or increased dosage, and there was no clear evidence that any of these strategies had a beneficial effect on TD symptoms (very low-quality evidence). We evaluated the addition to standard antipsychotic care of several treatments, but not anticholinergic treatments, for which we identified no trials. We found no clear effect of the addition of either benzodiazepines (two RCTs, n = 32, RR 1.12, 95% CI 0.6 to 2.09; very low quality) or vitamin E (six RCTs, n = 264, RR 0.95, 95% CI 0.89 to 1.01; low quality). Buspirone as an adjunctive treatment did have some effect in one small study (n = 42, RR 0.53, 95% CI 0.33 to 0.84; low quality), as did hypnosis and relaxation (one RCT, n = 15, RR 0.45, 95% CI 0.21 to 0.94; very low quality). We identified no studies focusing on TD in people with dementia. The NMA model found indirect estimates to be imprecise and failed to produce useful summaries on relative effects of interventions or interpretable results for decision-making. Consultation with people with/at risk of TD highlighted that management of TD remains a concern, and found that people are deeply disappointed at the length of time it has taken researchers to address the issue.

LIMITATIONS

Most studies remain small and poorly reported.

CONCLUSIONS

Clinicians, policy-makers and people with/at risk of TD are little better informed than they were decades ago. Underpowered trials of limited quality repeatedly fail to provide answers.

FUTURE WORK

TD reviews have data from current trials extracted, tabulated and traceable to source. The NMA highlights one context in which support for this technique is ill advised. All relevant trials, even if not primarily addressing the issue of TD, should report appropriate binary outcomes on groups of people with this problem. Randomised trials of treatments for people with established TD are indicated. These should be large (> 800 participants), necessitating accrual through accurate local/national registers, including an intervention with acceptable treatments and recording outcomes used in clinical practice.

STUDY REGISTRATION

This study is registered as PROSPERO CRD4201502045.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Non-VMAT2 inhibitor treatments for the treatment of tardive dyskinesia

Although VMAT2-inhibitors are now established as first-line treatment for tardive dyskinesia, not all patients respond to, or tolerate them. Numerous other agents have been adopted to treat tardive dyskinesia, but with variable results and generally lower quality methodologic reports. Amantadine is the most promising but benzodiazepines, branched chain neutral amino acids, Vitamin B6, several nutraceuticals, and botulinum toxin injections might help some patients. In all cases, better placebo controlled trials are needed before definitive recommendations can be made.

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).

Natural Medicines for Psychotic Disorders: A Systematic Review

Patients with psychotic disorders regularly use natural medicines, although it is unclear whether these are effective and safe. The aim of this study was to provide an overview of evidence for improved outcomes by natural medicines. A systematic literature search was performed through Medline, PsycINFO, CINAHL, and Cochrane until May 2015. In 110 randomized controlled trials, evidence was found for glycine, sarcosine, N-acetylcysteine, some Chinese and ayurvedic herbs, ginkgo biloba, estradiol, and vitamin B6 to improve psychotic symptoms when added to antipsychotics. Ginkgo biloba and vitamin B6 seemed to reduce tardive dyskinesia and akathisia. Results on other compounds were negative or inconclusive. All natural agents, except reserpine, were well tolerated. Most study samples were small, study periods were generally short, and most results need replication. However, there is some evidence for beneficial effects of certain natural medicines.

Vitamin E for antipsychotic-induced tardive dyskinesia

BACKGROUND

Antipsychotic (neuroleptic) medication is used extensively to treat people with chronic mental illnesses. Its use, however, is associated with adverse effects, including movement disorders such as tardive dyskinesia (TD) - a problem often seen as repetitive involuntary movements around the mouth and face. Vitamin E has been proposed as a treatment to prevent or decrease TD.

OBJECTIVES

The primary objective was to determine the clinical effects of vitamin E in people with schizophrenia or other chronic mental illness who had developed antipsychotic-induced TD.The secondary objectives were:1. to examine whether the effect of vitamin E was maintained as duration of follow-up increased;2. to test the hypothesis that the use of vitamin E is most effective for those with early onset TD (less than five years) 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 included reports if they were controlled trials dealing with people with antipsychotic-induced TD and schizophrenia who remained on their antipsychotic medication and had been randomly allocated to either vitamin E or to a placebo, no intervention, or any other intervention.

DATA COLLECTION AND ANALYSIS

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

MAIN RESULTS

The review now includes 13 poorly reported randomised trials (total 478 people), all participants were adults with chronic psychiatric disorders, mostly schizophrenia, and antipsychotic-induced TD. There was no clear difference between vitamin E and placebo for the outcome of TD: not improved to a clinically important extent (6 RCTs, N = 264, RR 0.95, 95% CI 0.89 to 1.01, low-quality evidence). However, people allocated to placebo may show more deterioration of their symptoms compared with those given vitamin E (5 RCTs, N = 85, RR 0.23, 95% CI 0.07 to 0.76, low-quality evidence). There was no evidence of a difference in the incidence of any adverse effects (9 RCTs, N = 205, RR 1.21, 95% CI 0.35 to 4.15, very low-quality evidence), extrapyramidal adverse effects (1 RCT, N = 104, MD 1.10, 95% CI -1.02 to 3.22, very low-quality evidence), or acceptability of treatment (measured by participants leaving the study early) (medium term, 8 RCTs, N = 232, RR 1.07, 95% CI 0.64 to 1.80, very low-quality evidence). No trials reported on social confidence, social inclusion, social networks, or personalised quality of life, outcomes designated important to patients. There is no trial-based information regarding the effect of vitamin E for those with early onset of TD.

AUTHORS' CONCLUSIONS

Small trials of limited quality suggest that vitamin E may protect against deterioration of TD. There is no evidence that vitamin E improves symptoms of this problematic and disfiguring condition once established. New and better trials are indicated in this under-researched area, and, of the many adjunctive treatments that have been given for TD, vitamin E would be a good choice for further evaluation.

Tardive dyskinesia – how is it prevented and treated?

Tardive dyskinesia (TD), literally meaning a late occurring, abnormal movement disorder, was first described by Schonecker in 1957, about five years after the discovery of chlorpromazine (cited in Kane, 1992). TD generally occurs after long-term antipsychotic therapy: Kane et al (1984) reported that the incidence was increased with each subsequent year of exposure to antipsychotics, starting with an incidence of 5% after one year of exposure and increasing by 5% each subsequent year. Certainly, the prevalence of TD has increased over the last 20 years, probably as the result of more patients being exposed to antipsychotics for longer periods.

Safety assessment of Withania somnifera extract standardized for Withaferin A: Acute and sub-acute toxicity study

Background

The use of Withania somnifera is increasing due to a number of its chemical constituents found useful for health.

Objective

The present study was carried out to investigate the potential adverse effects (if any) of a standardized Withania somnifera extract (WSE) in rats following acute and sub chronic administration.

Materials and methods

The toxicity study was performed in Wistar rats by oral administration. An acute toxicity study was done at the dose of 2000 mg/kg. In the sub-acute study, Wistar rats (10/sex/group) were administered via gavage 0 (control), 500, 1000, 2000 mg/kg body weight/day of WSE for 28 days. Among two additional satellite groups, one group did not receive any drug while the second group received 2000 mg/kg/day for 28 days. At the end of study, the animals sacrificed and their body weight, hematology, serum chemistry, and histopathology evaluation was done.

Results

In acute toxicity studies, oral LD50 of WSE in Wistar rats was greater than 2000 mg/kg body weight. Compared to the control group in sub-acute toxicity study, administration of extract did not show any toxicologically significant treatment related changes in clinical observations, ophthalmic examination, body weight gain, feed consumption, clinical pathology evaluation, and organ weight. Hematological and serum chemistry parameters were within the normal limits. Terminal necropsy did not reveal any treatment related gross or histopathological findings.

Conclusion

Based on this study, the no-observed-adverse-effect-level of WSE is 2000 mg/kg body weight, the highest level tested.

Antioxidant treatments for schizophrenia

BACKGROUND

There is accumulating evidence that progressive changes in brain structure and function take place as schizophrenia unfolds. Among many possible candidates, oxidative stress may be one of the mediators of neuroprogression, grey matter loss and subsequent cognitive and functional impairment. Antioxidants are exogenous or endogenous molecules that mitigate any form of oxidative stress or its consequences. They may act from directly scavenging free radicals to increasing anti-oxidative defences. There is evidence that current treatments impact oxidative pathways and may to some extent reverse pro-oxidative states in schizophrenia. The existing literature, however, indicates that these treatments do not fully restore the deficits in antioxidant levels or restore levels of oxidants in schizophrenia. As such, there has been interest in developing interventions aimed at restoring this oxidative balance beyond the benefits of antipsychotics in this direction. If antioxidants are to have a place in the treatment of this serious condition, the relevant and up-to-date information should be available to clinicians and investigators.

OBJECTIVES

To evaluate the effect of antioxidants as add-on treatments to standard antipsychotic medication for improving acute psychotic episodes and core symptoms, and preventing relapse in people with schizophrenia.

SEARCH METHODS

We searched the Cochrane Schizophrenia Group's Study-Based Register of Trials which is based on regular searches of CINAHL, BIOSIS, AMED, Embase, PubMed, MEDLINE, PsycINFO, and registries of clinical trials. There are no language, time, document type, or publication status limitations for inclusion of records in the register. We ran this search in November 2010, and again on 8 January 2015. We also inspected references of all identified studies for further trials and contacted authors of trials for additional information.

SELECTION CRITERIA

We included reports if they were randomised controlled trials (RCTs) involving people with schizophrenia who had been allocated to either a substance with antioxidant potential or to a placebo as an adjunct to standard antipsychotic treatment.

DATA COLLECTION AND ANALYSIS

We independently extracted data from these trials and we estimated risk ratios (RR) or mean differences (MD), with 95% confidence intervals (CI). We assessed risk of bias for included studies and created a 'Summary of findings' table using GRADE.

MAIN RESULTS

The review includes 22 RCTs of varying quality and sample size studying Ginkgo biloba, N-acetyl cysteine (NAC), allopurinol, dehydroepiandrosterone (DHEA), vitamin C, vitamin E or selegiline. Median follow-up was eight weeks. Only three studies including a minority of the participants reported our a priori selected primary outcome of clinically important response. Short-term data for this outcome (measured as at least 20% improvement in scores on Positive and Negative Syndrome Scale (PANSS)) were similar (3 RCTs, n = 229, RR 0.77, 95% CI 0.53 to 1.12, low quality evidence). Studies usually reported only endpoint psychopathology rating scale scores. Psychotic symptoms were lower in those using an adjunctive antioxidant according to the PANSS ( 7 RCTS, n = 584, MD -6.00, 95% CI -10.35 to -1.65, very low quality evidence) and the Brief Psychiatric Rating Scale (BPRS) (8 RCTS, n = 843, MD -3.20, 95% CI -5.63 to -0.78, low quality evidence). There was no overall short-term difference in leaving the study early (16 RCTs, n = 1584, RR 0.73, 95% CI 0.48 to 1.11, moderate quality evidence), or in general functioning (2 RCTs, n = 52, MD -1.11, 95% CI -8.07 to 5.86, low quality evidence). Adverse events were generally poorly reported. Three studies reported useable data for 'any serious adverse effect', results were equivocal (3 RCTs, n = 234, RR 0.65, 95% CI 0.19 to 2.27, low quality evidence). No evidence was available for relapse, quality of life or service use.

AUTHORS' CONCLUSIONS

Although 22 trials could be included in this review, the evidence provided is limited and mostly not relevant to clinicians or consumers. Overall, although there was low risk of attrition and selective data reporting bias within the trials, the trials themselves were not adequately powered and need more substantial follow-up periods. There is a need for larger trials with longer periods of follow-up to be conducted. Outcomes should be meaningful for those with schizophrenia, and include measures of improvement and relapse (not just rating scale scores), functioning and quality of life and acceptability and, importantly, safety data.

Oxidative stress and tardive dyskinesia: pharmacogenetic evidence

Tardive dyskinesia (TD) is a serious adverse effect of long-term antipsychotic use. Because of genetic susceptibility for developing TD and because it is difficult to predict and prevent its development prior to or during the early stages of medication, pharmacogenetic research of TD is important. Additionally, these studies enhance our knowledge of the genetic mechanisms underlying abnormal dyskinetic movements, such as Parkinson's disease. However, the pathophysiology of TD remains unclear. The oxidative stress hypothesis of TD is one of the possible pathophysiologic models for TD. Preclinical and clinical studies of the oxidative stress hypothesis of TD indicate that neurotoxic free radical production is likely a consequence of antipsychotic medication and is related to the occurrence of TD. Several studies on TD have focused on examining the genes involved in oxidative stress. Among them, manganese superoxide dismutase gene Ala-9Val polymorphisms show a relatively consistent association with TD susceptibility, although not all studies support this. Numerous pharmacogenetic studies have found a positive relationship between TD and oxidative stress based on genes involved in the antioxidant defense mechanism, dopamine turnover and metabolism, and other antioxidants such as estrogen and melatonin. However, many of the positive findings have not been replicated. We expect that more research will be needed to address these issues.

Free radicals, antioxidant defense systems, and schizophrenia

The etiopathogenic mechanisms of schizophrenia are to date unknown, although several hypotheses have been suggested. Accumulating evidence suggests that excessive free radical production or oxidative stress may be involved in the pathophysiology of schizophrenia as evidenced by increased production of reactive oxygen or decreased antioxidant protection in schizophrenic patients. This review aims to summarize the basic molecular mechanisms of free radical metabolism, the impaired antioxidant defense system and membrane pathology in schizophrenia, their interrelationships with the characteristic clinical symptoms and the implications for antipsychotic treatments. In schizophrenia, there is accumulating evidence of altered antioxidant enzyme activities and increased levels of lipid peroxidation, as well as altered levels of plasma antioxidants. Moreover, free radical-mediated abnormalities may contribute to specific aspects of schizophrenic symptomatology and complications of its treatment with antipsychotic drugs, as well as the development of tardive dyskinesia (TD). Finally, the potential therapeutic strategies implicated by the accumulating data on oxidative stress mechanisms for the treatment of schizophrenia are discussed.

Treatment of neurolept-induced tardive dyskinesia

Tardive dyskinesia (TDK) includes orobuccolingual movements and "piano-playing" movements of the limbs. It is a movement disorder of delayed onset that can occur in the setting of neuroleptic treatment as well as in other diseases and following treatment with other drugs. The specific pathophysiology resulting in TDK is still not completely understood but possible mechanisms include postsynaptic dopamine receptor hypersensitivity, abnormalities of striatal gamma-aminobutyric acid (GABA) neurons, and degeneration of striatal cholinergic interneurons. More recently, the theory of synaptic plasticity has been proposed. Considering these proposed mechanisms of disease, therapeutic interventions have attempted to manipulate dopamine, GABA, acetylcholine, norepinephrine and serotonin pathways and receptors. The data for the effectiveness of each class of drugs and the side effects were considered in turn.

Antioxidant supplements for prevention of mortality in healthy participants and patients with various diseases

BACKGROUND

Our systematic review has demonstrated that antioxidant supplements may increase mortality. We have now updated this review.

OBJECTIVES

To assess the beneficial and harmful effects of antioxidant supplements for prevention of mortality in adults.

SEARCH METHODS

We searched The Cochrane Library, MEDLINE, EMBASE, LILACS, the Science Citation Index Expanded, and Conference Proceedings Citation Index-Science to February 2011. We scanned bibliographies of relevant publications and asked pharmaceutical companies for additional trials.

SELECTION CRITERIA

We included all primary and secondary prevention randomised clinical trials on antioxidant supplements (beta-carotene, vitamin A, vitamin C, vitamin E, and selenium) versus placebo or no intervention.

DATA COLLECTION AND ANALYSIS

Three authors extracted data. Random-effects and fixed-effect model meta-analyses were conducted. Risk of bias was considered in order to minimise the risk of systematic errors. Trial sequential analyses were conducted to minimise the risk of random errors. Random-effects model meta-regression analyses were performed to assess sources of intertrial heterogeneity.

MAIN RESULTS

Seventy-eight randomised trials with 296,707 participants were included. Fifty-six trials including 244,056 participants had low risk of bias. Twenty-six trials included 215,900 healthy participants. Fifty-two trials included 80,807 participants with various diseases in a stable phase. The mean age was 63 years (range 18 to 103 years). The mean proportion of women was 46%. Of the 78 trials, 46 used the parallel-group design, 30 the factorial design, and 2 the cross-over design. All antioxidants were administered orally, either alone or in combination with vitamins, minerals, or other interventions. The duration of supplementation varied from 28 days to 12 years (mean duration 3 years; median duration 2 years). Overall, the antioxidant supplements had no significant effect on mortality in a random-effects model meta-analysis (21,484 dead/183,749 (11.7%) versus 11,479 dead/112,958 (10.2%); 78 trials, relative risk (RR) 1.02, 95% confidence interval (CI) 0.98 to 1.05) but significantly increased mortality in a fixed-effect model (RR 1.03, 95% CI 1.01 to 1.05). Heterogeneity was low with an I(2)- of 12%. In meta-regression analysis, the risk of bias and type of antioxidant supplement were the only significant predictors of intertrial heterogeneity. Meta-regression analysis did not find a significant difference in the estimated intervention effect in the primary prevention and the secondary prevention trials. In the 56 trials with a low risk of bias, the antioxidant supplements significantly increased mortality (18,833 dead/146,320 (12.9%) versus 10,320 dead/97,736 (10.6%); RR 1.04, 95% CI 1.01 to 1.07). This effect was confirmed by trial sequential analysis. Excluding factorial trials with potential confounding showed that 38 trials with low risk of bias demonstrated a significant increase in mortality (2822 dead/26,903 (10.5%) versus 2473 dead/26,052 (9.5%); RR 1.10, 95% CI 1.05 to 1.15). In trials with low risk of bias, beta-carotene (13,202 dead/96,003 (13.8%) versus 8556 dead/77,003 (11.1%); 26 trials, RR 1.05, 95% CI 1.01 to 1.09) and vitamin E (11,689 dead/97,523 (12.0%) versus 7561 dead/73,721 (10.3%); 46 trials, RR 1.03, 95% CI 1.00 to 1.05) significantly increased mortality, whereas vitamin A (3444 dead/24,596 (14.0%) versus 2249 dead/16,548 (13.6%); 12 trials, RR 1.07, 95% CI 0.97 to 1.18), vitamin C (3637 dead/36,659 (9.9%) versus 2717 dead/29,283 (9.3%); 29 trials, RR 1.02, 95% CI 0.98 to 1.07), and selenium (2670 dead/39,779 (6.7%) versus 1468 dead/22,961 (6.4%); 17 trials, RR 0.97, 95% CI 0.91 to 1.03) did not significantly affect mortality. In univariate meta-regression analysis, the dose of vitamin A was significantly associated with increased mortality (RR 1.0006, 95% CI 1.0002 to 1.001, P = 0.002).

AUTHORS' CONCLUSIONS

We found no evidence to support antioxidant supplements for primary or secondary prevention. Beta-carotene and vitamin E seem to increase mortality, and so may higher doses of vitamin A. Antioxidant supplements need to be considered as medicinal products and should undergo sufficient evaluation before marketing.

Drug-induced movement disorders

This comprehensive review covers approaches for both the recognition and management of drug-induced movement disorders. Pharmacotherapeutic approaches for treating akathisia, dystonia, Parkinsonism and tardive dyskinesia are explored. The importance of early detection via periodic assessment is discussed.

Antioxidant therapeutics for schizophrenia

Pharmaceutical treatment for millions worldwide who have schizophrenia is limited to a handful of antipsychotics. Despite the proven efficacy of these drugs, the overall outcome for schizophrenia remains suboptimal. Thus, alternative treatment options are urgently needed. One possible approach may be antioxidant therapy. The extant evidence for the role of oxidative stress in the pathophysiology of schizophrenia offers a hypothesis-derived therapeutic approach in the form of antioxidants. Vitamins C and E, for example, are suitable for human clinical trials because they are readily available, inexpensive, and relatively safe. Research into the therapeutic use of antioxidants in schizophrenia can be grouped into two main clusters: for psychopathology and for side effects. Of these studies, some have been carefully conducted, but majority are open label. Use of antioxidants for treatment-related side effects has been more extensively investigated. The totality of the evidence to date suggests that specific antioxidants, such as N-acetyl cysteine, may offer tangible benefits for the clinical syndrome of schizophrenia, and vitamin E may offer salutary effects on glycemic effects of antipsychotics. However, a great deal of fundamental clinical research remains to be done before antioxidants can be routinely used therapeutically for schizophrenia and treatment-related complications.

Tardive dyskinesia: treatment with aripiprazole

Tardive dyskinesia is characterized by choreiform movements, or rhythmic abnormal involuntary movements of the face, mouth, tongue, trunk, and limbs. It is frequently associated with the use of neuroleptic medications. The choreiform movements are irreversible in some patients, even after the drug is withdrawn. Although no reliable treatment for tardive dyskinesia exists, atypical antipsychotics are associated with a significantly lower incidence of tardive dyskinesia than typical antipsychotics. Moreover, recent reports suggest that atypical antipsychotics may have a beneficial effect on tardive dyskinesia remission. Until recently, evidence for the effectiveness of aripiprazole on tardive dyskinesia has been mixed. Aripiprazole has a unique mechanism of action and has various effects in tardive dyskinesia. The drug acts as a partial D₂ receptor agonist that can stabilize D₂ up-regulation, and as a partial 5-HT_1A receptor agonist and a 5-HT_2A receptor antagonist, and can increase the release of dopamine in the striatum.

Vitamin E for neuroleptic-induced tardive dyskinesia

BACKGROUND

Antipsychotic (neuroleptic) medication is used extensively to treat people with chronic mental illnesses. Its use, however, is associated with adverse effects, including movement disorders such as tardive dyskinesia (TD) - a problem often seen as repetitive involuntary movements around the mouth and face. Vitamin E has been proposed as a treatment to prevent or decrease TD.

OBJECTIVES

To determine the effects of vitamin E for people with schizophrenia or other chronic mental illnesses who also developed neuroleptic-induced TD.

SEARCH STRATEGY

We searched the Cochrane Schizophrenia Group Trials Register (March 2010), inspected references of all identified studies for further trials and contacted authors of trials for additional information.

SELECTION CRITERIA

We included reports if they were controlled trials dealing with people with neuroleptic-induced TD and schizophrenia who had been randomly allocated to either vitamin E or to a placebo or no intervention.

DATA COLLECTION AND ANALYSIS

We independently extracted data from these trials and we estimated risk ratios (RR) or mean differences (MD), with 95% confidence intervals (CI). We assumed that people who dropped out had no improvement.

MAIN RESULTS

The review now includes 11 poorly reported randomised trials (total 427 people). There was no clear difference between vitamin E and placebo for the outcome of 'clinically relevant improvement in TD' (6 trials, 256 people, RR 0.95 CI 0.89 to 1.02). For the outcome of 'any improvement in TD symptoms', again, we found no clear difference between groups (7 trials, 311 people, RR 0.86 CI 0.75 to 1.00). However, people allocated to placebo showed more deterioration of their symptoms compared with those given vitamin E (5 trials, 98 people, RR 0.38 CI 0.16 to 0.9). There was no difference in the incidence of adverse effects (9 trials, 203 people, RR 1.29 CI 0.51 to 3.24) or leaving the study early (medium term 6 trials, 173 people, RR 1.29 CI 0.72 to 2.3). There is no trial-based information regarding the effect of vitamin E for those with early onset of TD.

AUTHORS' CONCLUSIONS

Small trials of limited quality suggest that vitamin E may protect against deterioration of TD. There is no evidence that vitamin E improves symptoms of this problematic and disfiguring condition once established. New and better trials are indicated in this under-researched area, and, of the many adjunctive treatments that have been given for TD, vitamin E would be a good choice for further evaluation.

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.

Antioxidant supplements for prevention of mortality in healthy participants and patients with various diseases

BACKGROUND

Animal and physiological research as well as observational studies suggest that antioxidant supplements may improve survival.

OBJECTIVES

To assess the effect of antioxidant supplements on mortality in primary or secondary prevention randomised clinical trials.

SEARCH STRATEGY

We searched The Cochrane Library (Issue 3, 2005), MEDLINE (1966 to October 2005), EMBASE (1985 to October 2005), and the Science Citation Index Expanded (1945 to October 2005). We scanned bibliographies of relevant publications and wrote to pharmaceutical companies for additional trials.

SELECTION CRITERIA

We included all primary and secondary prevention randomised clinical trials on antioxidant supplements (beta-carotene, vitamin A, vitamin C, vitamin E, and selenium) versus placebo or no intervention. Included participants were either healthy (primary prevention trials) or had any disease (secondary prevention trials).

DATA COLLECTION AND ANALYSIS

Three authors extracted data. Trials with adequate randomisation, blinding, and follow-up were classified as having a low risk of bias. Random-effects and fixed-effect meta-analyses were performed. Random-effects meta-regression analyses were performed to assess sources of intertrial heterogeneity.

MAIN RESULTS

Sixty-seven randomised trials with 232,550 participants were included. Forty-seven trials including 180,938 participants had low risk of bias. Twenty-one trials included 164,439 healthy participants. Forty-six trials included 68111 participants with various diseases (gastrointestinal, cardiovascular, neurological, ocular, dermatological, rheumatoid, renal, endocrinological, or unspecified). Overall, the antioxidant supplements had no significant effect on mortality in a random-effects meta-analysis (relative risk [RR] 1.02, 95% confidence interval [CI] 0.99 to 1.06), but significantly increased mortality in a fixed-effect model (RR 1.04, 95% CI 1.02 to 1.06). In meta-regression analysis, the risk of bias and type of antioxidant supplement were the only significant predictors of intertrial heterogeneity. In the trials with a low risk of bias, the antioxidant supplements significantly increased mortality (RR 1.05, 95% CI 1.02 to 1.08). When the different antioxidants were assessed separately, analyses including trials with a low risk of bias and excluding selenium trials found significantly increased mortality by vitamin A (RR 1.16, 95% CI 1.10 to 1.24), beta-carotene (RR 1.07, 95% CI 1.02 to 1.11), and vitamin E (RR 1.04, 95% CI 1.01 to 1.07), but no significant detrimental effect of vitamin C (RR 1.06, 95% CI 0.94 to 1.20). Low-bias risk trials on selenium found no significant effect on mortality (RR 0.91, 95% CI 0.76 to 1.09).

AUTHORS' CONCLUSIONS

We found no evidence to support antioxidant supplements for primary or secondary prevention. Vitamin A, beta-carotene, and vitamin E may increase mortality. Future randomised trials could evaluate the potential effects of vitamin C and selenium for primary and secondary prevention. Such trials should be closely monitored for potential harmful effects. Antioxidant supplements need to be considered medicinal products and should undergo sufficient evaluation before marketing.

Protective effects of olanzapine and haloperidol on serum withdrawal-induced apoptosis in SH-SY5Y cells

PURPOSE

Recent clinical studies have suggested that treatment with second generation antipsychotic drugs such as olanzapine may prevent progressive alterations of brain structure in patients with schizophrenia. However, the molecular mechanisms underlying these different effects remain to be determined. We investigated the mechanisms of action of olanzapine and haloperidol, on serum withdrawal apoptosis in human neuroblastoma SH-SY5Y cells.

METHODS

SH-SY5Y cells were cultured with olanzapine and haloperidol in medium with or without serum. We determined the effects of the drugs on cell viability against serum withdrawal by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay. Additionally, to explore the drugs' actions, Western blot was performed to examine the expression of key genes involved in GSK-3beta-mediated signaling, notably GSK-3beta, beta-catenin, and Bcl-2.

RESULTS

SH-SY5Y cells suffered about a 38% loss in cell number under serum-free conditions for 48 h. Olanzapine (10-200 muM) up to 100 muM significantly attenuated serum withdrawal-induced cell loss (p<0.01), and a dose of 100 muM also increased cell viability (p<0.05). In contrast, haloperidol (0.01-10 muM) did not affect cell viability but exacerbated cell death at 10 muM under serum-free conditions (p<0.01). Western blot analysis showed that olanzapine, but not haloperidol, prevented the serum withdrawal-induced decrease in levels of neuroprotective proteins such as p-GSK-3beta, beta-catenin, and Bcl-2 (p<0.01), whereas haloperidol robustly reduced the levels of these proteins at a 10 muM dose in serum-starved cells (p<0.05). Moreover, olanzapine alone significantly increased phosphorylation of GSK-3beta under normal conditions (p<0.05).

CONCLUSIONS

This study showed that olanzapine may have neuroprotective effects, whereas haloperidol was apparently neurotoxic. The actions of signaling systems associated with GSK-3beta may be key targets for olanzapine and haloperidol, but their effects are distinct. These differences suggest different therapeutic effects of first and second generation antipsychotic drugs in patients with schizophrenia.

Effects of vitamin E supplementation on plasma membrane permeabilization and fluidization induced by chlorpromazine in the rat brain

Neurotransmitter receptors play a key role in most research on antipsychotic drugs, but little is known about the effects of these drugs on the plasma membrane in the central nervous system. Therefore, we investigated whether chlorpromazine (CPZ), a typical phenothiazine antipsychotic drug, affects the plasma membrane integrity in the rat brain, and if so, whether these membrane alterations can be prevented by dietary supplementation with vitamin E, which has been shown to be an antioxidant and also a membrane-stabilizer. Leakage of [(18)F]2-fluoro-2-deoxy-D-glucose ([(18)F]FDG)-6-phosphate from rat striatal slices and decrease in 1,6-diphenyl-1,3,5-hexatriene fluorescence anisotropy were used as indexes for plasma membrane permeabilization and fluidization, respectively. CPZ induced leakage of [(18)F]FDG-6-phosphate from striatal slices, and the leakage was delayed in the vitamin E-supplemented group compared to that in the normal diet group. The decrease in plasma membrane anisotropy induced by CPZ was significantly attenuated by vitamin E supplementation. Chronic treatment with alpha-phenyl-N-tert-butyl nitrone, a free radical scavenger, had no effect on CPZ-induced plasma membrane permeabilization, and the treatment with CPZ did not induce lipid peroxidation. CPZ can reduce plasma membrane integrity in the brain, and this reduction can be prevented by vitamin E via its membrane-stabilizing properties, not via its antioxidant activity.

Evidence that lithium protects against tardive dyskinesia: the Curaçao Extrapyramidal syndromes study VI

Lithium may have neuroprotective properties and therefore could affect the occurrence of tardive dyskinesia (TD). We conducted a nine-year follow-up study with one baseline and six follow-up assessments including all psychiatric inpatients in Curaçao (N=194). TD was measured with the Abnormal Involuntary Movement Rating Scale (AIMS). There were 758 follow-up observations in the 166 patients (mean age 54.4 yrs, SD 16.0) with at least one follow-up assessment. Most patients (74%) had schizophrenia. The mean baseline score of the AIMS was 4.1 (SD 4.7). Sixteen patients (9.6%) used lithium at baseline and eight patients started lithium during follow-up. Prevalent and incident lithium significantly reduced the severity of existing TD with respectively 2.3 and 2.9 point reduction on the AIMS (AIMS score range: 0-23) and a standardised effect size of 0.5 for prevalent TD and 0.6 for incident TD. In the restricted sample of those with a baseline score of zero on the AIMS, prevalent lithium significantly lowered the risk of new abnormal movements (standardised effect size of 0.7). In conclusion, the use of lithium was significantly negatively associated with both persistence and onset of TD. These results suggest a beneficial effect on TD of lithium in some patients using long-term antipsychotics.

Diphenyl diselenide decreases the prevalence of vacuous chewing movements induced by fluphenazine in rats

RATIONALE

Chronic treatment with neuroleptics causes, as a side effect, tardive dyskinesia in humans; however, the mechanisms involved in its pathophysiology remain unclear.

OBJECTIVES

The purpose of this study was to examine the effects of diphenyl diselenide, an organoselenium compound with antioxidant properties, in an animal model of vacuous chewing movements (VCMs) induced by long-term treatment with fluphenazine.

RESULTS

Adult male rats were treated during 24 weeks with fluphenazine (25 mg/kg, intramuscularly [i.m.], once every 21 days) and diphenyl diselenide (1 mg/kg, subcutaneously, three times a week). VCMs and body weight gain were quantified every 3 weeks. The fluphenazine treatment produced VCMs in the majority of the treated rats (87% after 24 weeks). Concomitant treatment with diphenyl diselenide decreased the prevalence of VCMs to 50%. Additionally, we separated the rats that developed or did not develop VCMs. We did not find any statistical differences among the groups when oxidative stress parameters were evaluated. Chronic fluphenazine treatment significantly decreased [(3)H]-dopamine uptake. Concomitant treatment with diphenyl diselenide was not able to prevent this decrease in those rats that developed VCMs.

CONCLUSIONS

Our data suggest that the reduction in dopamine transport can be a possible mechanism related to the maintenance of VCMs in rats. Moreover, diphenyl diselenide seems to be a promising pharmacological agent in the reduction in the prevalence of VCMs in rats.

Effect of spirulina maxima on the haloperidol induced tardive dyskinesia and oxidative stress in rats

Haloperidol is a widely used neuroleptic drug for the treatment of acute and chronic psychosis. The use of haloperidol is limited by extrapyramidal movement disorders such as Parkinsonism, akathesia, dystonia, and tardive dyskinesia (TD). Treatment with haloperidol increases oxyradicals which are implicated in TD. Spirulina is widely used as nutritional supplement rich in proteins and antioxidants. The present study is proposed to study the effect of spirulina on haloperidol induced TD and oxidative stress by studying TD, various enzymatic and nonenzymatic antioxidants and lipid peroxidation. Haloperidol 1 mg/kg/i.p was used to induce vacuous chewing movements in rats. Spirulina maxima suspended in 1% between 80 at a dose of 45, 90 and 180 mg/kg were administered by gavage along with haloperidol from 21st day to 49th day of treatment. Spirulina supplementation at a dose of 180 mg/kg significantly improved enzymatic and nonenzymatic antioxidants and decreased the tardive dyskinesia induced by haloperidol. In conclusion, the results of present investigation suggest that spirulina decreases haloperidol induced oxidative stress and TD by many mechanisms as it is cocktail of antioxidants. On chronic use it may inhibit haloperidol induced reduced expression of DNA thereby increases the expression of enzymatic and nonenzymatic antioxidants and protects against oxidative stress induced neurodegeneration and TD.

Vitamin E supplementation in Alzheimer's disease, Parkinson's disease, tardive dyskinesia, and cataract: Part 2

OBJECTIVE

To review clinical trials evaluating the safety and efficacy of vitamin E supplementation in Alzheimer's disease, Parkinson's disease, tardive dyskinesia, and cataract.

DATA SOURCES

Using the MeSH terms alpha-tocopherol, tocopherols, vitamin E, Parkinson disease, tardive dyskinesia, Alzheimer disease, cataract, and clinical trials, a literature review was conducted to identify peer-reviewed articles in MEDLINE (1966-July 2005).

STUDY SELECTION AND DATA EXTRACTION

Published materials including original research, review articles, and meta-analyses were reviewed. Only English-language articles and trials that included vitamin E alone or in combination with other vitamins or minerals were reviewed. Emphasis was placed on prospective, randomized, double-blind, placebo-controlled clinical trials.

DATA SYNTHESIS

The clinical studies demonstrated contradicting results regarding the benefits of vitamin E in Parkinson's disease, tardive dyskinesia, and cataract. The study reviewed for Alzheimer's disease seemed to show benefit when vitamin E was used; however, the statistical methods employed are questionable. There is enough evidence from large, well-designed studies to discourage the use of vitamin E in Parkinson's disease, cataract, and Alzheimer's disease. We recommend that vitamin E be considered a treatment option in patients with tardive dyskinesia only if they are newly diagnosed.

CONCLUSIONS

We encourage patients to supplement with vitamin E-rich foods. The use of a daily multivitamin, which usually contains 30 IU of alpha-tocopherol, may be beneficial; however, we discourage individual vitamin E supplements that usually contain 400 IU of alpha-tocopherol.

Extrapyramidal symptoms with atypical antipsychotics : incidence, prevention and management

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

Important role of striatal catalase in aging- and reserpine-induced oral dyskinesia

Tardive dyskinesia, the most serious iatrogenic movement disorder, has been tentatively associated with nigrostriatal dopaminergic supersensitivity and with oxidative stress. It is also suggested that long-term neuroleptic treatment does not cause oral dyskinesia (OD), but interacts with some substrate of brain aging, resulting in the premature emergence of OD, that can occur spontaneously with aging. In order to investigate a possible role of nigrostriatal dopaminergic supersensitivity and of oxidative stress in aging- and reserpine-induced OD, the stereotyped behavior induced by dopaminergic agonists, a functional index of dopaminergic striatal activity, as well as the striatal antioxidant enzymes glutathione peroxidase and catalase were assessed. We demonstrate that, opposite to normotensive Wistar rats (NWR), spontaneously hypertensive rats (SHR) do not develop aging- or reserpine-OD. There were no differences between NWR and SHR in stereotyped behavior or in striatal glutathione peroxidase activity. Adult and old SHR presented higher striatal catalase activity relative to NWR, and aging increased it only in SHR. The catalase inhibitor aminotriazole reverted the absence of aging- and reserpine-induced OD in SHR. Our results suggest an important role of striatal catalase in the development of reserpine- and aging-induced OD.

The effect of vitamin E treatment on tardive dyskinesia and blood superoxide dismutase: a double-blind placebo-controlled trial

Free radicals may be involved in the pathogenesis of tardive dyskinesia (TD). Vitamin E, a free radical scavenger, has been reported to improve symptoms of TD. The present study was designed to replicate this finding in a group of Chinese patients with TD, and to examine the effect of vitamin E treatment on blood superoxide dismutase (SOD), a critical enzyme in the detoxification of free radicals. Forty-one inpatients with TD completed a double-blind, placebo-controlled, parallel-group study of vitamin E. Twenty-two of the patients were randomly assigned to receive a fixed dose of 1200 IU/d vitamin E, and 19 were assigned to a placebo for 12 weeks. Patients were assessed primarily using the Abnormal Involuntary Movement Scale (AIMS) at baseline, weeks 6 and 12. Blood SOD levels were measured by radioimmunometric assay before and after treatment. The results showed that the reduction in AIMS score from baseline was significantly higher with vitamin E treatment compared with placebo (45.9% vs. 4.3%). Blood SOD levels were significantly increased after treatment with vitamin E (P = 0.001), but no change with placebo treatment (P < 0.05). These results support earlier findings of the efficacy of vitamin E in the treatment of TD. Moreover, the efficacy of vitamin E may be due to its ability to increase SOD level, which may reduce oxidative injure in tardive dyskinesia.

Mouvements anormaux d’origine médicamenteuse : les syndromes tardifs

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

Oxidative mechanisms and tardive dyskinesia

Tardive dyskinesia has been and continues to be a significant problem associated with long-term antipsychotic use, but its pathophysiology remains unclear. In the last 10 years, preclinical studies of the administration of antipsychotics to animals, as well as clinical studies of oxidative processes in patients given antipsychotic medications, with and without tardive dyskinesia, have continued to support the possibility that neurotoxic free radical production may be an important consequence of antipsychotic treatment, and that such production may relate to the development of dyskinetic phenomena. In line with this hypothesis, evidence has accumulated for the efficacy of antioxidants, primarily vitamin E (alpha-tocopherol), in the treatment and prevention of tardive dyskinesia. Early studies suggested a modest effect of vitamin E treatment on existing tardive dyskinesia, but later studies did not demonstrate a significant effect. Because evidence has continued to accumulate for increased oxidative damage from antipsychotic medications, but less so for the effectiveness of vitamin E, especially in cases of long-standing tardive dyskinesia, alternative antioxidant approaches to the condition may be warranted. These approaches may include the use of antioxidants as a preventive measure for tardive dyskinesia or the use of other antioxidants or neuroprotective drugs, such as melatonin, for established tardive dyskinesia.

Oral dyskinesias and histopathological alterations in substantia nigra after long-term haloperidol treatment of old rats

The pathophysiologic basis of tardive dyskinesia remains unclear, but several lines of evidence suggest that persistent neuronal changes in the basal ganglia produced by oxidative stress or glutamate toxicity may play a role, especially in the elderly. In the present study we examined whether histopathological alterations in substantia nigra are related to oral dyskinesia in a rodent model of tardive dyskinesia. Haloperidol decanoate (38 mg/kg/4 weeks) was administered to young (8 weeks) and old (38 weeks) rats for a total period of 28 weeks, and the development of vacuous chewing movements (VCM) was observed. Rats with high and low levels of VCM and saline-treated controls were analyzed for histopathological alterations. Reduced nerve cell number and atrophic neurons were prominent features in the substantia nigra of old rats with high levels of VCM. Some alterations were also present in the substantia nigra of the old rats with low levels of VCM and young rats with high VCM levels, but these were significantly less affected than the high VCM rats. These results show that the development of haloperidol-induced oral dyskinesias in old rats is associated with histopathological alterations in the substantia nigra. This suggests that nigral degeneration induced by neuroleptics may contribute to the development of persistent VCM in rats and possibly irreversible tardive dyskinesia in humans.

Classification and treatment of tardive syndromes

BACKGROUND

Tardive syndromes are a group of delayed-onset abnormal involuntary movement disorders induced by a dopamine receptor blocking agent. There are several phenomenologically distinct types of TS.

REVIEW SUMMARY

The term tardive dyskinesia has been used to refer to the TS that presents with rapid, repetitive, stereotypic movements mostly involving the oral, buccal, and lingual areas. Tardive dystonia can be focal, segmental, or generalized. It commonly affects the face and neck followed by the arms and trunk. It usually results in retrocollis when it involves the neck and trunk arching backwards when it involves the trunk. Tardive akathisia is characterized by a feeling of inner restlessness and jitteriness with an inability to sit or stand still. Other tardive syndromes include tardive tics, myoclonus, tremor, and withdrawal-emergent syndrome. It remains unclear whether tardive parkinsonism truly exists. The only way to prevent TS is to avoid its etiologic agents. Chronic use of dopamine receptor blocking agents should be limited as much as possible to patients with chronic psychoses. In general, for mild TS, reducing the neuroleptic dose, switching to an atypical agent, or discontinuing antipsychotic treatment altogether in the hope of facilitating remission is recommended. For moderate to severe TS, tetrabenazine or reserpine may be the most effective agent. Neuroleptics should be resumed to treat TD in the absence of active psychosis only as a last resort for persistent, disabling, and treatment-resistant TD.

CONCLUSIONS

The severity of the TS and the absolute need for antipsychotic therapy often dictate the treatment approach for this disorder.

Detection of TOAD-64 in adult rat brain as revealed by two-dimensional protein gel electrophoresis followed by MALDI mass spectrometry possible modulatory effect of chronic haloperidol treatment

The molecular mechanisms by which antipsychotic effects are achieved remain largely elusive. Possible mechanisms include the modulation of nerve cell gene expression. The antipsychotic drug haloperidol was administered orally (1.6 mg/kg) to adult rats for 3 weeks. Protein patterns in striata and forebrains were studied by two-dimensional gel electrophoresis (2-DE). One differentially regulated protein spot was identified by matrix-assisted laser desorption ionization mass spectrometry (MALDI-MS) after trypsin digest. Turned on after devision-64 kD (TOAD-64), the identified protein, was present in all gels and, in addition, was up-regulated in the striata but not in the forebrains of the haloperidol-treated animals by 43%. It is concluded that TOAD-64, typically regarded as a marker for commitment to neuronal differentiation during fetal development, also plays a role in adult rat forebrain and striatum and that its concentration is possibly modulated by haloperidol treatment.

Effect of Withania somnifera glycowithanolides on a rat model of tardive dyskinesia

Withania somnifera glycowithanolides (WSG) were investigated for their preventive effect on the animal model of tardive dyskinesia (TD), induced by once daily administration of the neuroleptic, haloperidol (1.5 mg/kg, i.p.), for 28 days. Involuntary orofacial movements (chewing movements, tongue protusion and buccal tremors) were assessed as TD parameters. WSG (100 and 200 mg, p.o.), administered concomitantly with haloperidol for 28 days, inhibited the induction of the neuroleptic TD. Haloperidol-induced TD was also attenuated by the antioxidant, vitamin E (400 and 800 mg/kg, p.o.), but remained unaffected by the GABA-mimetic antiepileptic agent, sodium valproate (200 and 400 mg/kg, p.o.), both agents being administered for 28 days like WSG. The results indicate that the reported antioxidant effect of WSG, rather than its GABA-mimetic action, may be responsible for the prevention of haloperidol-induced TD.

Oxidative damage and schizophrenia: an overview of the evidence and its therapeutic implications

Free radicals are highly reactive chemical species generated during normal metabolic processes. which in excess can lead to membrane damage. Elaborate antioxidant defence systems exist to protect against oxidative stress. There is accumulating evidence of altered antioxidant capacity in schizophrenia. Membrane dysfunction can be secondary to free radical-mediated pathology, and may contribute to specific aspects of schizophrenic symptomatology and complications of its treatment. Specifically, free radical-mediated abnormalities may contribute to the development of a number of clinically significant consequences, including prominent negative symptoms, tardive dyskinesia, neurological 'soft' signs and parkinsonian symptoms. Our previous results showing altered membrane dynamics and antioxidant enzyme activities in schizophrenia, and findings from other investigators, are consistent with the notion of free radical-mediated neurotoxicity in schizophrenia. These findings provide a theoretical basis from which the development of novel therapeutic strategies such as fatty acid and antioxidant supplementation can occur in the future.

Neurotoxicity associated with neuroleptic-induced oral dyskinesias in rats. Implications for tardive dyskinesia?

Tardive dyskinesia is a serious motor side effect of long-term treatment with neuroleptics, with an unknown pathophysiologic basis. Brain damage and aging are prominent risk-factors, and together with the persistent character of the disorder, it is likely that long-lasting neuronal changes are involved in the pathogenesis. It has been hypothesized that striatal neurodegeneration caused by excitotoxic mechanisms and oxidative stress may play an important role in the development of the disorder, and the scope of the present work is to review the evidence supporting this hypothesis. The rat model of tardive dyskinesia has been used extensively in the field, and the usefulness of this model will be discussed. Neuroleptics are able to induce oxidative stress in vitro and increase striatal glutamatergic activity in rats, which may lead to toxic effects in the striatum. Drugs that block excitotoxicity inhibit the development of persistent oral dyskinesia in the rat model, and impaired energy metabolism leads to increased frequency of oral dyskinesia. There are also signs of altered striatal histology in rats with high frequency of oral dyskinesia. Furthermore, markers of increased oxidative stress and glutamatergic neurotransmission have been found in the cerebrospinal fluid of patients with tardive dyskinesia. In conclusion, several lines of evidence implicate neurotoxic events in the development of neuroleptic induced tardive dyskinesia.

Tardive Dyskinesia

Although there are many published studies on the treatment of tardive dyskinesia (TD), relatively few treatments have proven to be consistently useful in clinical practice. Reviewed critically, most treatments have produced only slight to moderate benefit in less than half the patients treated. Emphasis instead is on prevention, prompt detection, and management of early and potentially reversible cases. If a patient develops dyskinesia while taking an antipsychotic drug (APD), ideal management is immediate discontinuation of the APD, if this is psychiatrically feasible. The manifestations of TD should be documented and the patient examined to exclude other possible causes of dyskinesia. APDs should then be withheld in the hope that the dyskinesia will disappear. Although the dyskinesia may fade within several weeks, it has the potential to recur if APD treatment is reintroduced. Psychiatric reevaluation to consider alternative psychiatric diagnoses or treatments is strongly advised. If there is no alternative to reintroducing an APD for psychiatric treatment, then an atypical neuroleptic should be considered. Because dyskinesia is very often not disturbing enough to require treatment, the need for treatment of TD should be carefully assessed. For mild dyskinesia, low doses of a benzodiazepine (eg, clonazepam) may reduce the amount of both dyskinesia and associated anxiety. Anticholinergic drugs are unhelpful and may aggravate TD but, similar to their effect in idiopathic dystonia, may be effective in tardive dystonia. Botulinum toxin injections are of considerable value in managing localized forms of tardive dystonia, such as retrocollis or blepharospasm. Tetrabenazine and reserpine are presynaptic dopamine depletors that may have considerable efficacy in TD, especially tardive dystonia; however, their use is often limited by side effects. Based on the rationale that TD may be due to formation of free radicals, vitamin E has been used for treatment of TD, with mixed results. In some patients with persistent and disabling TD that fails to remit even after the patient is no longer taking an APD, it may be necessary to resume treatment eventually with a typical APD. This approach should be considered only as a last resort to suppress TD, however, because it carries the risk of preventing remission and possibly aggravating TD. In this case, further attempts to taper and discontinue the APD are recommended. At present, there is no evidence that established TD continues to progress in severity with continued APD exposure. This nonprogressive character of TD may provide to be a consolation to the patient and family and is also of potential medical-legal importance.

Nutritional Contributions to the CNS Pathophysiology of HIV-1 Infection and Implications for Treatment

Nutritional deficiencies are commonplace in patients with human immunodeficiency virus type 1 (HIV-1) infection, and recent research has indicated that nutritional factors may play an important role in the pathogenesis of HIV-1 disease. Although nutritional deficiencies are unlikely to be the primary causative factor in disease progression, they may contribute to cognitive dysfunction, neurologic abnormalities, mood disturbance, and immune dysregulation associated with HIV-1 infection. Furthermore, deficiencies of specific micronutrients have been associated with increased risk of HIV-1-associated mortality. This article will briefly summarize the role of macronutrient deficiency, the interactions of specific micronutrient deficiencies with neuropsychiatric functioning, and the role of these factors in HIV-1 disease progression. Since recent research has shown that normalization of many nutritional deficits and supplementation beyond normal levels are associated with improvements in neuropsychiatric functioning, potential treatment implications will also be discussed.

Vitamin E for neuroleptic-induced tardive dyskinesia

BACKGROUND

Neuroleptic (antipsychotic) medication is used extensively to treat people with chronic mental illnesses. However, it is associated with a wide range of adverse effects, including movement disorders such as tardive dyskinesia (TD). Vitamin E has been proposed as a treatment to prevent or decrease the severity of TD.

OBJECTIVES

To determine the clinical effects of vitamin E for people with schizophrenia or other chronic mental illnesses who also developed neuroleptic-induced tardive dyskinesia.

SEARCH STRATEGY

Electronic searches of Biological Abstracts (1982-1998), The Cochrane Schizophrenia Group's Register (September 1998), EMBASE (1980-98), LILACS (1982-96), MEDLINE (1966-98), PsycLIT (1974-98), SCISEARCH, handsearching the references of all identified studies and contacting the first author of each included trial.

SELECTION CRITERIA

Reports identified in the search were included if they were controlled trials dealing with people with neuroleptic-induced TD and schizophrenia or other chronic mental illness who had been randomly allocated to either vitamin E or to a placebo or no intervention.

DATA COLLECTION AND ANALYSIS

Data were independently extracted from these trials by each reviewer and Peto odds ratios (OR) or average differences, with the 95% confidence intervals (CI) were estimated. The reviewers assumed that people who dropped out had no improvement.

MAIN RESULTS

Eight studies were included, and another three are currently awaiting further data from authors. The overall results for both, 'clinically relevant improvement' and 'any improvement' of TD symptoms, were in favour of vitamin E (OR 0.16, CI 0.04-0.7, NNT 5 CI 2.-32 and OR 0.23, CI 0.10-0.55, NNT 4 CI 2. 5-12 respectively). People who had not used vitamin E showed more deterioration of their symptoms (OR 0.20, CI 0.04-0.93). No difference could be found regarding the presence of adverse effects or leaving the study early before the end of study. There is no trial-based information regarding the effect of vitamin E for those with early onset of TD.

REVIEWER'S CONCLUSIONS

Small trials with uncertain quality of randomisation, tend to suggest that vitamin E improves the symptoms of TD. Methodological problems such as small sample size, short term interventions, and inappropriate use of crossover design need to be dealt with in any future studies. The results of a recently completed trial involving 158 participants are eagerly awaited.

Vitamin E in the treatment of tardive dyskinesia

OBJECTIVE

To review the efficacy of vitamin E in the treatment of tardive dyskinesia (TD).

DATA SOURCES

Published articles and abstracts in English were identified from January 1986 to March 1999 by MEDLINE and International Pharmaceutical Abstracts searches using the terms vitamin E, alpha-tocopherol, and tardive dyskinesia. Additional articles were identified from the references of the retrieved articles and cross- referencing selected articles.

DATA EXTRACTION

All clinical trials evaluating the use of vitamin E in human subjects with TD were reviewed. Selected articles also included those considered to be helpful in providing a basic introduction to TD pathophysiology and management.

DATA SYNTHESIS

TD occurs in approximately 20% of patients treated with neuroleptics. The resulting dyskinesias can be irreversible and are often psychologically and physically debilitating. Recent research suggests that TD may be a result of neuronal damage inflicted by free radicals generated from increased neurotransmitter turnover and metabolism. Vitamin E as a naturally occurring free radical scavenger has been evaluated in the treatment of TD. Eighteen completed trials are available either in completed or abstract form. Twelve of these trials have produced positive results with vitamin E in the treatment of TD. Patients who have had TD for less than five years appear to respond better than patients with long-standing TD.

CONCLUSIONS

Research suggests that vitamin E offers benefit in the management of a subgroup of patients with TD. Further investigation is needed to ascertain continued efficacy with long-term use as well as the role of vitamin E in TD prophylaxis.

The treatment of tardive dyskinesia--a systematic review and meta-analysis

This systematic review aimed to collate randomized controlled trials (RCTs) of various interventions used to treat tardive dyskinesia (TD) and, where appropriate, to combine the data for meta-analysis. Clinical trials were identified by electronic searches, handsearches and contact with principal investigators. Data were extracted independently by two reviewers, for outcomes related to improvement, deterioration, side-effects and drop out rates. Data were pooled using the Mantel-Haenzel Odds Ratio (fixed effect model). For treatments that had significant effects, the number needed to treat (NNT) was calculated. From 296 controlled clinical trials, data were extracted from 47 trials. For most interventions, we could identify no RCT-derived evidence of efficacy. A meta-analysis showed that baclofen, deanol and diazepam were no more effective than a placebo. Single RCTs demonstrated a lack of evidence of any effect for bromocriptine, ceruletide, clonidine, estrogen, gamma linolenic acid, hydergine, lecithin, lithium, progabide, seligiline and tetrahydroisoxazolopyridinol. The meta-analysis found that five interventions were effective: L-dopa, oxypertine, sodium valproate, tiapride and vitamin E; neuroleptic reduction was marginally significant. Data from single RCTs revealed that insulin, alpha methyl dopa and reserpine were more effective than a placebo. There was a significantly increased risk of adverse events associated with baclofen, deanol, L-dopa, oxypertine and reserpine. Meta-analysis of the impact of placebo (n=485) showed that 37.3% of participants showed an improvement. Interpretation of this systematic review requires caution as the individual trials identified tended to have small sample sizes. For many compounds, data from only one trial were available, and where meta-analyses were possible, these were based on a small number of trials. Despite these concerns, the review facilitated the interpretation of the large and diverse range of treatments used for TD. Clinical recommendations for the treatment of TD are made, based on the availability of RCT-derived evidence, the strength of that evidence and the presence of adverse effects.

Haloperidol-induced changes in glutathione and energy metabolism: effect of nicergoline

The aim of this study was to evaluate the possible effects of nicergoline, a semisynthetic ergot derivative, on the biochemical changes observed during chronic treatment with haloperidol in male Sprague-Dawley rats. Chronic treatment with haloperidol induced a significant decrease in the cellular glutathione (GSH) content in selected areas of the brain (cerebellum, striatum and cortex) and in the liver. Prolonged nicergoline administration was able to antagonize the haloperidol-induced GSH decrease, maintaining the GSH concentration at levels comparable to those observed in the control group. Analysis of the energy charge revealed changes similar to those observed for GSH: haloperidol induced a significant decrease in ATP and energy charge that was completely reversed by repeated nicergoline administration. In conclusion, chronic treatment with the classical antipsychotic haloperidol induces profound biochemical changes in the brain and in the liver. Nicergoline treatment is able to counteract the haloperidol-induced decrease in GSH levels and energy charge, suggesting a potential role of the drug in the treatment of neuroleptic-induced side effects.

Induction of NF-kappaB activity during haloperidol-induced oxidative toxicity in clonal hippocampal cells: suppression of NF-kappaB and neuroprotection by antioxidants

Haloperidol (HP), a dopamine receptor antagonist, is cytotoxic to mouse clonal hippocampal HT22 cells in a concentration-dependent manner and causes cell death by oxidative stress. The addition of HP to HT22 cells led to an increase in intracellular peroxides and a time-dependent drop in the intracellular glutathione levels. HP-induced oxidative cell death was prevented by the pineal hormone melatonin, its precursor N-acetyl serotonin, and most effectively by vitamin E (alpha-tocopherol). These antioxidants inhibited the intracellular peroxide accumulation and stabilized the glutathione content of HT22 cells after the challenge with HP. At the molecular level, HP specifically induced the DNA binding activity and the transcriptional activity of the redox-sensitive transcription factor NF-kappaB. This enhanced NF-kappaB activity could be blocked by the neuroprotective antioxidants. The specific suppression of NF-kappaB by its inhibitor IkappaBalpha partially protected the cells against HP, indicating that the activation of NF-kappaB may be involved in HP-induced oxidative cell death in vitro.

Tardive dyskinesia and serum iron indices

BACKGROUND

This study was undertaken to evaluate whether peripheral (serum) markers of iron status are associated with severity of the choreoathetoid movements seen in tardive dyskinesia (TD).

METHODS

Serum iron indices (ferritin, iron, and total iron binding capacity) and fluphenazine levels were measured in a group of 30 male DSM-III diagnosed schizophrenic patients chronically treated with fluphenazine decanoate. The severity of choreoathetoid movements was assessed with the Abnormal Involuntary Movement Scale (AIMS), and akathisia was assessed with the Barnes scale.

RESULTS

A significant positive correlation was observed between AIMS scores and serum ferritin. This relationship remained significant after controlling for age and plasma fluphenazine levels. No significant correlations were observed between serum iron or total iron binding capacity and choreoathetoid movement ratings. There were no significant associations between serum iron indices and akathisia ratings.

CONCLUSIONS

The data suggest that choreoathetoid movements are associated with serum ferritin levels in chronically medicated male schizophrenic patients. This relationship does not seem to be caused by an association of these variable with age or plasma fluphenazine levels. In addition, the relationship seems to be specific, since other iron indices and another extrapyramidal side effect (akathisia) do not demonstrate a similar relationship. In view of reports that antipsychotic medications change normal iron metabolism and increase iron uptake into the brain, the current results could be interpreted to suggest that serum ferritin levels may be a risk factor for TD in patients treated with "classic" antipsychotic medications.

High-dose vitamin E plus vitamin B6 treatment of risperidone-related neuroleptic malignant syndrome

We present a case of a 74-year-old patient with schizoaffective disorder, who developed risperidone-related neuroleptic malignant syndrome. This patient responded satisfactorily to the supportive management and vit E plus vit B6.