Structural brain changes associated with tardive dyskinesia in schizophrenia

Immunosenescence-related T cell phenotypes and white matter in schizophrenia patients with tardive dyskinesia

Schizophrenia patients with tardive dyskinesia (TD) are associated with accelerated biological aging, immunological dysfunction, and premature morbidity and mortality. Older individuals are particularly vulnerable to TD development. As a characteristic of immunosenescence, alterations in the relative proportions of naïve or memory T cell subpopulations may be negatively or positively associated with brain structure abnormalities; however, whether these changes are correlated with TD remains unclear. In this study, we investigated correlations between distributions of T cell phenotypes and brain structure abnormalities (especially white matter) in schizophrenia patients with (TD) and without (NTD) TD (n = 50 and 58, respectively) relative to healthy controls (HC, n = 41). Immune markers, including naïve (CD45RA+), memory (CD45RO+), and apoptotic (CD95+) CD4+ and CD8+ T cells, were examined by flow cytometry, as were the intracellular levels of cytokines (interferon (IFN)-γ, interleukin (IL)-6, IL-1β, and tumor necrosis factor (TNF)-α) in CD8 + CD45RA + CD95+ and CD8 + CD45RO + CD95+ T cells. MRI was employed to evaluate the fractional anisotropy (FA) of white matter tracts and subcortical volumes, following published routines. The percentage of CD8 + CD45RO + CD95+ T cells was higher in TD compared with NTD and HC groups and correlated with the choroid plexus volume in TD group. The intracellular level of IFN-γ in CD8 + CD45RO + CD95+ T cells, the FA of the fornix/stria terminalis, and the pallidum volume were correlated with orofacial TD, whereas the FAs of the inferior fronto-occipital fasciculus, cingulum, and superior longitudinal fasciculus were correlated with limb-truncal TD. These findings provide preliminary evidence that the association between immunosenescence-related T cell subpopulations and brain structure may underline the pathological process of TD.

Differential regulation of G protein-coupled receptor-associated proteins in the caudate and the putamen of cynomolgus macaques following chronic ethanol drinking

The dorsal striatum is composed of the caudate nucleus and the putamen in human and non-human primates. These two regions receive different cortical projections and are functionally distinct. The caudate is involved in the control of goal-directed behaviors, while the putamen is implicated in habit learning and formation. Previous reports indicate that ethanol differentially influences neurotransmission in these two regions. Because neurotransmitters primarily signal through G protein-coupled receptors (GPCRs) to modulate neuronal activity, the present study aimed to determine whether ethanol had a region-dependent impact on the expression of proteins that are involved in the trafficking and function of GPCRs, including G protein subunits and their effectors, protein kinases, and elements of the cytoskeleton. Western blotting was performed to examine protein levels in the caudate and the putamen of male cynomolgus macaques that self-administered ethanol for 1 year under free access conditions, along with control animals that self-administered an isocaloric sweetened solution under identical operant conditions. Among the 18 proteins studied, we found that the levels of one protein (PKCβ) were increased, and 13 proteins (Gαi1/3, Gαi2, Gαo, Gβ1γ, PKCα, PKCε, CaMKII, GSK3β, β-actin, cofilin, α-tubulin, and tubulin polymerization promoting protein) were reduced in the caudate of alcohol-drinking macaques. However, ethanol did not alter the expression of any proteins examined in the putamen. These observations underscore the unique vulnerability of the caudate nucleus to changes in protein expression induced by chronic ethanol exposure. Whether these alterations are associated with ethanol-induced dysregulation of GPCR function and neurotransmission warrants future investigation.

Deep Brain Stimulation in the Treatment of Tardive Dyskinesia

Tardive dyskinesia (TD) is a phenomenon observed following the predominantly long-term use of dopamine receptor blockers (antipsychotics) widely used in psychiatry. TD is a group of involuntary, irregular hyperkinetic movements, mainly in the muscles of the face, eyelid, lips, tongue, and cheeks, and less frequently in the limbs, neck, pelvis, and trunk. In some patients, TD takes on an extremely severe form, massively disrupting functioning and, moreover, causing stigmatization and suffering. Deep brain stimulation (DBS), a method used, among others, in Parkinson's disease, is also an effective treatment for TD and often becomes a method of last resort, especially in severe, drug-resistant forms. The group of TD patients who have undergone DBS is still very limited. The procedure is relatively new in TD, so the available reliable clinical studies are few and consist mainly of case reports. Unilateral and bilateral stimulation of two sites has proven efficacy in TD treatment. Most authors describe stimulation of the globus pallidus internus (GPi); less frequent descriptions involve the subthalamic nucleus (STN). In the present paper, we provide up-to-date information on the stimulation of both mentioned brain areas. We also compare the efficacy of the two methods by comparing the two available studies that included the largest groups of patients. Although GPi stimulation is more frequently described in literature, our analysis indicates comparable results (reduction of involuntary movements) with STN DBS.

Tardive Syndrome Is a Mysterious Phenomenon with Different Clinical Manifestations-Review

Tardive syndrome (TS) refers to persistent hyperkinetic, hypokinetic, and sensory complaints appearing after chronic neuroleptics and other dopamine receptor-blocking agents (DRBAs). It is defined as involuntary movements, often rhythmic, choreiform, or athetoid, involving the tongue, face, extremities, and sensory urges such as akathisia and lasts for a few weeks. TS develops in association with neuroleptic medication usage for a few months at least. There is usually a delay between the initiation of the causative drug and the onset of abnormal movements. However, it was soon noted that TS can also develop early, even days or weeks after DRBAs begin. However, the longer the exposure, the greater the risk of developing TS. Tardive dyskinesia, dystonia, akathisia, tremor, and parkinsonism are frequent phenomenologies of this syndrome.

Why Does Tardive Dyskinesia Have Oro-facial Predominance? A Network Analysis

Tardive dyskinesia is a involuntary hyperkinetic disorder which usually occurs in older patients after long-term treatment with antipsychotic drugs. These dyskinesias are mostly irreversible and are frequently expressed in the tongue, cheeks, mandible, perioral area and other regions of the face. In this theoretical study we asked the question, why does tardive dyskinesia often have orofacial predominance? What might be the underlying neural network structure which contributes to this propensity? Graph analysis of high-level cortico-striato-thalamo-cortical network structure suggests a connectivity bottleneck. The number of walks of different lengths from the substantia nigra pars reticulata (SNr) to other vertices, as well as the returning cycles are the lowest in the network, which may indicate a higher damage susceptibility of this node. Analysis was also performed on published data from a recent high resolution histological study on cortico-striato-thalamo-cortical networks in rodents. Finer network partitioning and adjacency matrices demonstrated that the SNr has a heterogeneous connectivity structure and the number of local walks from nodes neighboring orofacial neural representation is higher, indicating possible early compensatory escape routes. However, with more extensive SNr damage the larger circuit compensation might be limited. This area of inquiry is important for future research, because identifying key vulnerable structures may provide more targeted therapeutical interventions.

The effects of cannabidiol on behavioural and oxidative stress parameters induced by prolonged haloperidol administration

OBJECTIVES

We investigated the influence of oral cannabidiol (CBD) on vacuous chewing movements (VCM) and oxidative stress parameters induced by short- and long-term administration of haloperidol in a rat model of tardive dyskinesia (TD).

METHODS

Haloperidol was administered either sub-chronically via the intraperitoneal (IP) route or chronically via the intramuscular (IM) route to six experimental groups only or in combination with CBD. VCM and oxidative stress parameters were assessed at different time points after the last dose of medication.

RESULTS

Oral CBD (5 mg/kg) attenuated the VCM produced by sub-chronic administration of haloperidol (5 mg/kg) but had minimal effects on the VCM produced by chronic administration of haloperidol (50 mg/kg). In both sub-chronic and chronic haloperidol groups, there were significant changes in brain antioxidant parameters compared with CBD only and the control groups. The sub-chronic haloperidol-only group had lower glutathione activity compared with sub-chronic haloperidol before CBD and the control groups; also, superoxide dismutase, catalase, and 2,2-diphenyl-1-picrylhydrazyl activities were increased in the sub-chronic (IP) haloperidol only group compared with the CBD only and control groups. Nitric oxide activity was increased in sub-chronic haloperidol-only group compared to the other groups; however, the chronic haloperidol group had increased malondialdehyde activity compared to the other groups.

CONCLUSIONS

Our findings indicate that CBD ameliorated VCM in the sub-chronic haloperidol group before CBD, but marginally in the chronic haloperidol group before CBD. There was increased antioxidant activity in the sub-chronic group compared to the chronic group.

Disentangling dyskinesia from parkinsonism in motor structures of patients with schizophrenia

Patients with schizophrenia frequently suffer from motor abnormalities, but underlying alterations in neuroarchitecture remain unclear. Here, we aimed to disentangle dyskinesia from parkinsonism in motor structures of patients with schizophrenia and to assess associated molecular architecture. We measured grey matter of motor regions and correlated volumetric estimates with dyskinesia and parkinsonism severity. Associations with molecular architecture were identified by cross-modal spatial correlations between ensuing maps of abnormality-related volume alterations and neurotransmitter maps from healthy populations. Both phenomena were linked to (specific) striatal and basal forebrain reductions as well as to D₁ receptor density. Dyskinesia also manifested in cerebellar decrease, while parkinsonism was associated with less motor cortex volume. The parkinsonism-related brain pattern was additionally associated with 5-HT_1A/2A and µ-opioid receptors distribution. Findings suggest the need to develop psychopharmacological compounds that display not only selectivity for receptor subtypes but also anatomical selectivity for alleviating dyskinesia without worsening parkinsonism and vice versa.

Genome wide study of tardive dyskinesia in schizophrenia

Tardive dyskinesia (TD) is a severe condition characterized by repetitive involuntary movement of orofacial regions and extremities. Patients treated with antipsychotics typically present with TD symptomatology. Here, we conducted the largest GWAS of TD to date, by meta-analyzing samples of East-Asian, European, and African American ancestry, followed by analyses of biological pathways and polygenic risk with related phenotypes. We identified a novel locus and three suggestive loci, implicating immune-related pathways. Through integrating trans-ethnic fine mapping, we identified putative credible causal variants for three of the loci. Post-hoc analysis revealed that SNPs harbored in TNFRSF1B and CALCOCO1 independently conferred three-fold increase in TD risk, beyond clinical risk factors like Age of onset and Duration of illness to schizophrenia. Further work is necessary to replicate loci that are reported in the study and evaluate the polygenic architecture underlying TD.

Abnormal functional connectivity of motor circuit in the schizophrenic patients with tardive dyskinesia: A resting-state fMRI study

BACKGROUND

Animal and neuroimaging studies suggest that the volume of the motor-circuit region decreases in tardive dyskinesia (TD). This study examined the differences in functional connectivity within the motor circuit of patients with schizophrenia with and without TD to further clarify how the dysfunction is related to the pathogenesis of TD.

METHODS

Functional magnetic resonance images were taken of 56 schizophrenic patients with TD (TD group), 64 without TD (non-TD group), and 68 healthy controls (HC group). The motor-circuit area was selected as the seed region for a whole brain resting-state functional connectivity (rsFC) analysis. Psychopathological symptoms and TD severity were assessed with the Positive and Negative Syndrome Scale (PANSS) and Abnormal Involuntary Movement Scale (AIMS), respectively. Group differences and correlations among 18 brain regions of interest (e.g., the global strength of connectivity between two regions) were analyzed.

RESULTS

The analysis of variance results were as follows: The three groups exhibited rsFC losses in the left primary motor cortex, bilateral parietal cortices, right postcentral gyrus, right putamen, right superior parietal lobule, right supplementary motor area and bilateral thalami (false discovery rate,p < 0.05). The TD group showed a significant rsFC loss between the right postcentral gyrus and the inferior frontal gyrus of the left triangular part when compared with the non-TD group (AlphaSim, p < 0.001), which was negatively correlated with the AIMS total score (r=-0.259, p = 0.03).

CONCLUSIONS

These findings may suggest dysfunction of the postcentral and inferior frontal gyri of the triangular part in patients with schizophrenia and TD.

Management of Tardive Syndrome: Medications and Surgical Treatments

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

Altered serum levels of glial cell line-derived neurotrophic factor in male chronic schizophrenia patients with tardive dyskinesia

OBJECTIVES

Many research indicate that the tardive dyskinesia (TD) is generally linked with long-term antipsychotic therapy for schizophrenia. Glial cell line-derived neurotrophic factor (GDNF) is a critical role in the protection of catecholaminergic, dopaminergic, and cholinergic neurons. Thus, we examined the serum GDNF levels in schizophrenia patients with TD (WTD) and without TD (NTD) and compared with healthy controls (HC), respectively.

METHODS

Totally 75 males with schizophrenia were recruited into this study. All were measured by the Diagnostic and Statistical Manual of Mental Disorders, fifth edition, the Positive and Negative Syndrome Scale, and the Abnormal Involuntary Movement Scale (AIMS). The patient group was divided into two subgroups: WTD (n = 32) and NTD (n = 43) according to the AIMS score. Fifty-three healthy controls matching in age and gender were also enlisted from the region. GDNF levels were examined with sandwich enzyme-linked immunosorbent assay.

RESULTS

Analysis of variance indicated significant differences between the three groups (P = 0.012); GDNF levels in the WTD group were significantly different from those in the NTD (P = 0.030) and HC (P = 0.003) groups.

CONCLUSION

Decreased GDNF levels in TD patients indicated that alterations in neurotrophic factors may be involved in the pathophysiology of TD, but the exact mechanisms need further investigation.

Tardive dyskinesia: motor system impairments, cognition and everyday functioning

The recent approval of treatments for tardive dyskinesia (TD) has rekindled interest in this chronic and previously recalcitrant condition. A large proportion of patients with chronic mental illness suffer from various degrees of TD. Even the newer antipsychotics constitute a liability for TD, and their liberal prescription might lead to emergence of new TD in patient populations previously less exposed to antipsychotics, such as those with depression, bipolar disorder, autism, or even attention deficit hyperactivity disorder. The association of TD with activity limitations remains poorly understood. We review potential new avenues of assessing the functional sequelae of TD, such as the performance of instrumental activities of daily living, residential status, and employment outcomes. We identify several mediating aspects, including physical performance measures and cognition, that may represent links between TD and everyday performance, as well as potential treatment targets.

Decreased Gray Matter Volume of Cuneus and Lingual Gyrus in Schizophrenia Patients with Tardive Dyskinesia is Associated with Abnormal Involuntary Movement

Tardive dyskinesia (TD) is a devastating motor disorder associated with the etiological process of schizophrenia or antipsychotic medication treatments. To examine whether cerebral morphological changes may manifest in TD, we used voxel-based morphometry to analyze high-resolution T1-weighted brain structural magnetic resonance images from 32 schizophrenics with TD (TD group), 31 schizophrenics without TD (non-TD group), and 32 healthy controls (HC group). We also assessed psychopathological symptoms with the Positive and Negative Syndrome Scale (PANSS), and TD severity with the Abnormal Involuntary Movement Scale (AIMS). We compared gray matter volumes (GMVs) among groups, and tested for correlations between GMV changes and psychopathological symptoms or TD severity. The results showed significant differences in GMV in the frontal and temporal cortices, insula and cerebellum among the three groups. Brainstem and inferior frontal and precentral gyri GMVs were significantly larger, whereas cuneus and lingual gyrus GMVs were significantly smaller in the TD group as compared to non-TD group. Further, the cuneus and lingual gyrus GMVs were positively correlated with AIMS scores in the TD group. The current results suggest that TD may be associated with the alterations in GMV that are different from that of schizophrenics without TD. Further studies are needed to confirm and to examine the functional significance of these structural findings.

Parkinsonism is associated to fronto-caudate disconnectivity and cognition in schizophrenia

The present work studies the possible relation of parkinsonism and fronto-caudate dysconnectivity, as well as its relation to cognition in schizophrenia patients. We assessed parkinsonism using Simpson-Angus scale and prefronto-caudate connectivity using diffusion magnetic resonance in 22 schizophrenia patients (11 first-episodes) and 14 healthy controls. Fractional anisotropy was calculated for the white matter tracts directly linking rostral middle prefrontal (RMPF) and superior medial prefrontal (SMPF) regions with caudate nucleus. Cognition was assessed using the Brief Assessment of Cognition in Schizophrenia Scale (BACS). Total parkinsonism scores were negatively related to fractional anisotropy in the right SMPF-caudate tract in patients, which was also found in the first-episode patients alone, but not in controls. Parkinsonism was also inversely associated in patients to performance in social cognition, verbal memory, working memory and performance speed tests. In conclusion, our data support the involvement of fronto-striatal dysconnectivity in parkinsonism in schizophrenia.

Resting-state Brain Activity Changes Associated with Tardive Dyskinesia in Patients with Schizophrenia: Fractional Amplitude of Low-frequency Fluctuation Decreased in the Occipital Lobe

We explored resting-state brain activity and its potential links to clinical parameters in schizophrenic patients with tardive dyskinesia (TD) using fractional amplitude of low-frequency fluctuations (fALFF). Resting-state functional magnetic resonance imaging data were acquired from 32 schizophrenic patients with TD (TD group), 31 without TD (NTD group), and 32 healthy controls (HC group). Clinical parameters including psychopathological symptoms, severity of TD, and cognitive function were assessed using the Positive and Negative Syndrome Scale, Abnormal Involuntary Movement Scale (AIMS), and Repeatable Battery for the Assessment of Neuropsychological Status, respectively. Pearson correlation analyses were performed to determine the relationship between the regions with altered fALFF values and clinical parameters in TD patients. The TD group showed decreased fALFF in the left middle occipital gyrus (MOG) and the right calcarine sulcus (CAL) compared to the HC group, and decreased fALFF in the left cuneus compared to the NTD group. In the TD group, fALFF values in the left MOG and the right CAL were correlated separately with the delayed memory score (r = 0.44, p = 0.027; r = 0.43, p = 0.028, respectively). The AIMS total score was negatively correlated to the visuospatial/constructional score (r = -0.53, p = 0.005). Our findings suggested that resting-state brain activity changes were associated with TD in schizophrenic patients. There was an association between the decreased brain activity in the occipital lobe and the delayed memory cognition impairment in this population.

Future directions in tardive dyskinesia research

Tardive dyskinesia (TD) research is at a crossroads because of renewed interest in this syndrome following the successful development and regulatory approval of two novel vesicular monoamine transport 2 (VMAT2) inhibitors. Despite these clinical advances, significant lacunae exist in the knowledge base of TD pathophysiology, prognosis, and epidemiology. Moreover, conflicting definitions of TD as either a syndrome that encompasses a broad array of related phenomena or as a specific subset of tardive syndromes are an impediment to both clinical and basic science research, and to educational efforts targeting nonspecialist clinicians. A unique opportunity is thus presented by the enhanced focus on TD to resolve fundamental issues with regards to nomenclature and clinical criteria, thereby facilitating more sophisticated surveillance and genetic and epidemiological research into tardive movement disorders related to dopamine receptor blocking agents. The widespread use of newer antipsychotics portends that TD will remain a persistent public health issue. This article will present one view of research avenues to be explored for this neuropsychiatric condition, including those that may yield immediate therapeutic benefits by extending expert knowledge into routine clinical care situations.

Distinct Associations of Motor Domains in Relatives of Schizophrenia Patients-Different Pathways to Motor Abnormalities in Schizophrenia?

INTRODUCTION

Aberrant motor function is an integral part of schizophrenia. In fact, abnormalities are frequently found in patients, in populations at risk, and in unaffected relatives. Motor abnormalities are suspected to be relevant for the clinical outcome and could probably predict the conversion from at-risk individuals to schizophrenia. Furthermore, motor function has been argued as endophenotype of the disorder. Yet, which particular motor domain may classify as a potential endophenotype is unknown. We aimed to compare schizophrenia patients, unaffected first-degree relatives and healthy controls for different motor domains. We expected impairments in all domains in patients and in some domains in relatives.

METHOD

We included 43 schizophrenia patients, 34 unaffected first-degree relatives of schizophrenia patients, and 29 healthy control subjects, matched for age, gender, and education level. We compared motor function of four motor domains between the groups. The domains comprise neurological soft signs (NSS), abnormal involuntary movements (dyskinesia), Parkinsonism, and fine motor function including simple [finger tapping (FT)] and complex fine motor function, (i.e., dexterity as measured with the coin rotation test). Furthermore, we tested the association of motor function of the four domains with working memory, frontal lobe function, and nonverbal intelligence for each group separately using within-group bivariate correlations.

RESULTS

Schizophrenia patients showed poorer motor function in all tested domains compared to healthy controls. First-degree relatives had intermediate ratings with aberrant function in two motor domains. In detail, relatives had significantly more NSS and performed poorer in the FT task than controls. In contrast, complex fine motor function was intact in relatives. Relatives did not differ from controls in dyskinesia or Parkinsonism severity.

DISCUSSION

Taken together, schizophrenia patients have motor abnormalities in all tested domains. Thus, motor abnormalities are a key element of the disorder. Likewise, first-degree relatives presented motor deficits in two domains. A clear difference between relatives and healthy controls was found for NSS and FT. Thus, NSS and FT may be potential markers of vulnerability for schizophrenia. The lack of association between genetic risk and dyskinesia or Parkinsonism suggests distinct pathobiological mechanisms in the various motor abnormalities in schizophrenia.

Brain volume changes over the first year of treatment in schizophrenia: relationships to antipsychotic treatment

BACKGROUND

Progressive brain volume reductions have been described in schizophrenia, and an association with antipsychotic exposure has been reported.

METHODS

We compared percentage changes in grey and white matter volume from baseline to month 12 in 23 previously antipsychotic-naïve patients with a first episode of schizophrenia or schizophreniform disorder who were treated with the lowest effective dose of flupenthixol decanoate depot formulation, with 53 matched healthy individuals. Total antipsychotic dose was precisely calculated and its relationship with brain volume changes investigated. Relationships between volumetric changes and treatment were further investigated in terms of treatment response (changes in psychopathology and functionality) and treatment-related adverse-events (extrapyramidal symptoms and weight gain).

RESULTS

Excessive cortical volume reductions were observed in patients [-4.6 (6.6)%] v. controls [-1.12 (4.0)%] (p = 0.009), with no significant group differences for changes in subcortical grey matter and white matter volumes. In a multiple regression model, the only significant predictor of cortical volume change was total antipsychotic dose received (p = 0.04). Cortical volume change was not significantly associated with the changes in psychopathology, functionality, extrapyramidal symptoms and body mass index or age, gender and duration of untreated psychosis.

CONCLUSIONS

Brain volume reductions associated with antipsychotic treatment are not restricted to poor outcome patients and occur even with the lowest effective dose of antipsychotic. The lack of an association with poor treatment response or treatment-related adverse effects counts against cortical volume reductions reflecting neurotoxicity, at least in the short term. On the other hand, the volume reductions were not linked to the therapeutic benefits of antipsychotics.

Forgotten but not gone: new developments in the understanding and treatment of tardive dyskinesia

The broad use of atypical antipsychotics was expected to dramatically reduce the prevalence and incidence of tardive dyskinesia (TD), but data show that TD remains an important challenge due the persistent nature of its symptoms and resistance to numerous treatment modalities, including antipsychotic discontinuation. Recent insights on genetic risk factors and new concepts surrounding pathophysiology have spurred interest in the possibility of targeted treatment for TD. As will be reviewed in this article, the number of evidence-based strategies for TD treatment is small: only clonazepam, amantadine, ginkgo biloba extract, and the vesicular monoamine transporter 2 (VMAT2) inhibitor tetrabenazine have compelling data. Using new insights into the metabolism of tetrabenazine and the properties of its active metabolites, 2 modifications of tetrabenazine have been synthesized to improve the kinetic profile, and are currently involved in double-blind placebo controlled studies aimed at U.S. Food and Drug Administration (FDA) regulatory approval. The possible availability of these new agents, deuterated tetrabenazine and valbenazine, significantly widens the range of treatment choices for patients with TD. For clinicians with patients at risk for TD due to dopamine antagonist exposure, experience has shown that the problem of TD will be an ongoing issue in modern psychiatry, and that an appreciation of new developments in the pathophysiology of, risk factors for, and treatment of TD is crucial to managing this condition.

A Correlative Classification Study of Schizophrenic Patients with Results of Clinical Evaluation and Structural Magnetic Resonance Images

Patients with schizophrenia suffer from symptoms such as hallucination and delusion. There are currently a number of publications that discuss the treatment, diagnosis, prognosis, and damage in schizophrenia. This study utilized joint independent component analysis to process the images of GMV and WMV and incorporated the Wisconsin card sorting test (WCST) and the positive and negative syndrome scale (PANSS) to examine the correlation of obtained brain characteristics. We also used PANSS score to classify schizophrenic patients into acute and subacute cases, to analyze the brain structure differences. Finally, we used brain structure images and the error rate of the WCST as eigenvalues in support vector machine learning and classification. The results of this study showed that the frontal and temporal lobes of a normal brain are more apparent than those of a schizophrenia brain. The highest level of classification recognition reached 91.575%, indicating that the WCST error rate and characteristic changes in brain structure volume can be used to effectively distinguish schizophrenia and normal brains. Similarly, this result confirmed that the WCST and brain structure volume are correlated with the differences between schizophrenia and normal participants.

Therapeutic Perspective on Tardive Syndrome with Special Reference to Deep Brain Stimulation

Tardive syndrome (TDS) is a potentially permanent and irreversible hyperkinetic movement disorder caused by exposure to dopamine receptor blocking agents. Guidelines published by the American Academy of Neurology recommend pharmacological first-line treatment for TDS with clonazepam (level B), ginkgo biloba (level B), amantadine (level C), and tetrabenazine (level C). Recently, a class II study provided level C evidence for use of deep brain stimulation (DBS) of the globus pallidus internus (GPi) in patients with TDS. Although the precise pathogenesis of TDS remains to be elucidated, the beneficial effects of GPi-DBS in patients with TDS suggest that the disease may be a basal ganglia disorder. In addition to recent advances in understanding the pathophysiology of TDS, this article introduces the current use of DBS in the treatment of medically intractable TDS.

Utilizing the concept of geste antagoniste for conservative management of oro-mandibular tardive dyskinesia: a case report and mini-review

OBJECTIVE

This case report highlights the implication of the concept of "geste antagoniste" in conservatively managing oromotor dysfunction and its complications.

CLINICAL PRESENTATION

A 66-year-old female with a 1-year history of tardive dyskinesia (TD) was referred to the Craniofacial Pain Department (CPC) at Tufts University School of Dental Medicine for management of sore labial/lingual mucosa secondary to excessive daytime involuntary activity of the tongue, lips, and mandible. A detailed head/neck examination revealed excessive involuntary movements of the tongue, lips, and mandible with generalized tenderness of her masticatory muscles. No TMJ or bone pathology was evident in a panoramic radiograph.

INTERVENTION

A lower daytime appliance with bilateral posterior contacts was fabricated to protect her oral mucosa. On reevaluation, excessive movement of the jaw/tongue was significantly reduced with the presence of the appliance in her mouth. Face/neck muscle tenderness was also greatly reduced.

CONCLUSION

The use of oral appliance therapy in TD patients plays an important role in protecting the teeth/oral mucosa. The subsequent inhibition of excessive motor activity is proposed and should be further investigated.

Altered BDNF is correlated to cognition impairment in schizophrenia patients with tardive dyskinesia

BACKGROUND

Long-term antipsychotic treatment for schizophrenia is often associated with the emergence of tardive dyskinesia (TD), which is linked to greater cognitive impairment. Brain-derived neurotrophic factor (BDNF) plays a critical role in cognitive function, and schizophrenia patients with TD have lower BDNF levels than those without TD.

OBJECTIVE

This study examines the BDNF levels, the cognitive function, and the association of BDNF with cognitive function in schizophrenia patients with or without TD.

METHODS

We recruited 83 male chronic patients with (n=35) and without TD (n=48) meeting DSM-IV criteria for schizophrenia and 52 male control subjects. We examined the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) and BDNF levels for all subjects. Positive and Negative Symptom Scale (PANSS) and the Abnormal Involuntary Movement Scale (AIMS) were assessed in patients.

RESULTS

BDNF levels were lower in patients with than those without TD (p<0.05). RBANS total score (p<0.01) and subscales of immediate memory, visuospatial/constructional performance, and attention were lower in patients with than those without TD (all p<0.05). BDNF levels were positively associated with immediate memory in patients without TD, but negatively in TD patients (both p<0.05). Multiple regression analysis confirmed that in either TD or non-TD group, BDNF was an independent contributor to immediate memory (both p<0.05).

CONCLUSIONS

BDNF may be involved in the pathophysiology of TD. While the associations between BDNF and cognition in both TD and non-TD patients suggest a close relationship between BDNF and cognition, the different directions may implicate distinct mechanisms between TD and non-TD patients.

Association of altered CuZn superoxide dismutase and cognitive impairment in schizophrenia patients with tardive dyskinesia

Free radical-mediated abnormalities may contribute to the development of tardive dyskinesia (TD) and specific aspects of schizophrenia symptomatology such as cognitive deficits. Superoxide dismutase (SOD), a critical enzyme in the detoxification of superoxide radicals, was found to be abnormal in TD. While most of previous studies focused on the manganese isoform located in mitochondria, this study investigated the activities of isoform CuZnSOD present in the plasma. We recruited 113 male chronic patients with TD (n = 43) and without TD (n = 70) meeting DSM-IV criteria for schizophrenia, and 84 male control subjects. We examined the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), CuZnSOD activity for both the patient and control groups along with total antioxidant status (TAS) and malondialdehyde (MDA) levels in a subset of the cohort. Positive and Negative Symptom Scale (PANSS) and the Abnormal Involuntary Movement Scale (AIMS) were assessed in the patient group. Our results showed lower CuZnSOD activity and TAS levels, but higher MDA levels in patients with TD than those without TD (all p < 0.05). Patients with TD had lower RBANS subscales of Visuospatial/Constructional (p < 0.05) and attention (p < 0.01) than those without TD. Multiple regression analysis showed that in either TD or non-TD group, CuZnSOD was an independent contributor to the attention index of RBANS (both p < 0.05). These results implicated that TD patients suffered greater oxidative stress and cognitive dysfunction than non-TD patients. Oxidative stress could contribute to both TD development and cognitive impairment.

Movement disorders in neuroleptic-naïve patients with schizophrenia spectrum disorders

BACKGROUND

Spontaneous Movements Disorders (SMDs) or dyskinetic movements are often seen in patients with schizophrenia and other psychotic disorders, and are widely considered to be adverse consequences of the use of antipsychotic medications. Nevertheless, SMDs are also observed in the pre-neuroleptic ear and among patients who were never exposed to antipsychotic medications. The aim of this study was to determine the extent of SMDs among antipsychotic-naïve patients in a low income setting, and to evaluate contextually relevant risk factors.

METHODS

The study was a cross-sectional facility-based survey conducted at a specialist psychiatric hospital in Addis Ababa, Ethiopia. Consecutive consenting treatment-naïve patients with a diagnosis of schizophrenia, schizoaffective disorder and schizophreniform disorder contacting services for the first time were assessed using the Simpson-Angus Rating Scale (SAS) and the Abnormal Involuntary Movement Scale (AIMS) to evaluate the presence of SMDS. Scale for the Assessment of Negative Symptoms (SANS) and Scale for the Assessment of Positive Symptoms (SAPS) were administered to evaluate negative and positive symptom profiles respectively. Body mass index (BMI) was used as a proxy measure for nutritional status.

RESULT

Sixty-four patients, 67.2% male (n = 43), with first contact psychosis who met the DSM-IV-TR criteria for schizophrenia (n = 47), schizophreniform disorder (n= 5), and schizoaffective disorder (n = 12) were assessed over a two month study period. Seven patients (10.9%) had SMDs. BMI (OR = 0.6, 95% CI = 0.40, 0.89; p = 0.011) and increasing age (OR = 1.10; 95% CI = 1.02, 1.20; p = 0.017) were associated with SMD.

CONCLUSIONS

This finding supports previous suggestions that abnormal involuntary movements in schizophrenia and other psychotic disorders may be related to the pathophysiology of psychotic disorders and therefore cannot be attributed entirely to the adverse effects of neuroleptic medication.

Oxidative stress and the antipsychotic-induced vacuous chewing movement model of tardive dyskinesia: evidence for antioxidant-based prevention strategies

RATIONALE

Despite decades of research, tardive dyskinesia (TD) remains a poorly understood iatrogenic movement disorder with few effective treatments and no known cure. Accordingly, the development of an innocuous strategy to prevent or mitigate antipsychotic (AP)-associated TD would represent an important clinical advance. Supporting evidence for antioxidant (AX)-based treatment regimens can be found in the preclinical literature, where AP-induced vacuous chewing movements (VCMs) in rats are attenuated by the concurrent administration of direct and indirect AXs.

OBJECTIVES

Our aim was to review the preclinical literature examining the role of AX-promoting treatments in the prevention of AP-induced VCMs in rats.

METHODS

A literature search using Google Scholar and PubMed was performed. Relevant results were qualitatively reviewed.

RESULTS

Studies featuring a variety of naturally occurring and synthetic AX treatments were identified and included in the review. The majority of studies used haloperidol (HAL), a typical AP, to induce VCMs. Studies revealed reduced VCMs in co-treated rats, with favorable changes seen in markers of oxidative stress (OS) and AX status, but were limited by their short durations.

CONCLUSIONS

Some preclinical evidence suggests that the inclusion of a naturally occurring and benign AX compound as an adjunct to AP treatment may help guard patients against TD, but additional long-duration studies are needed. This AX-based strategy is further substantiated by accumulating evidence of preexisting OS abnormalities in schizophrenia (SZ).

Cognition impairment in schizophrenia patients with tardive dyskinesia: association with plasma superoxide dismutase activity

Long-term antipsychotic treatment for schizophrenia is often associated with the emergence of tardive dyskinesia (TD), and TD presence is also accompanied by more severe cognitive impairment. Oxidative stress-induced damage may be involved in the development of TD and contribute to cognitive deficits in schizophrenia. We examined the role of oxidative stress in relation to TD and cognitive deficits in schizophrenia using plasma manganese superoxide dismutase (MnSOD) as a biomarker. We recruited 83 male chronic patients with (n=32) and without TD (n=51) meeting DSM-IV criteria for schizophrenia, and 58 male control subjects. We examined the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) and MnSOD activity for all subjects. Positive and Negative Symptom Scale (PANSS) and the Abnormal Involuntary Movement Scale (AIMS) were assessed in the patients. MnSOD activity was lower in patients with TD than non-TD, and either TD or non-TD group had lower MnSOD levels than controls (all p<0.05). Patients with TD had lower RBANS total (p<0.05) and Visuospatial/Constructional subscale scores than non-TD patients (p<0.01), and either TD or non-TD group scored lower than the controls on all RBANS subscales (all p<0.001) except for the Visuospatial/Constructional index. Multiple regression analysis showed that in either TD or non-TD group, MnSOD was an independent contributor to the RBANS total score (both p<0.05). These findings suggest that TD patients suffered oxidative stress and cognition impairment at a more severe level than non-TD patients. Oxidative stress might serve as a functionally linking node between TD development and cognition dysfunction in schizophrenia.

Gray matter abnormalities in schizophrenia patients with tardive dyskinesia: a magnetic resonance imaging voxel-based morphometry study

OBJECTIVE

The pathophysiological mechanism of TD remains unknown. All previous studies, using the region-of-interest method, focused on basal ganglion areas, were with inconsistent results. This whole-brain voxel-based morphometry (VBM) study investigate the grey matter abnormality of TD and its correlates with clinical ratings.

METHOD

High resolution T1-weighted brain volumetric MRI from 25 schizophrenia patients with TD (TD group), 25 age-, gender-, and handedness-matched schizophrenia patients without TD (non-TD group), and 25 matched healthy subjects (NC group) were analyzed using a VBM approach. Clinical ratings included the Positive and Negative Symptom Scale (PANSS), Abnormal Involuntary Movement Scale (AIMS), and the Simpson-Angus Scale (SAS).

RESULTS

The TD group had significantly smaller total gray matter volumes than the NC group (p = 0.05). Compared to the non-TD group, the TD group had significantly higher PANSS negative (p<0.001), SAS (p<0.001), and AIMS (p<0.001) scores; and smaller bilateral inferior frontal gyrus, which correlated negatively with the PANSS negative scores (r = -0.366, p<0.05); and smaller right superior frontal gyrus, which correlated negatively with AIMS scores (r = -0.399, p<0.001), and PANSS general score (r = -0.338, p<0.05).

LIMITATIONS

The cross-section design can't separate the gray matter change to TD from the context of the illness of schizophrenia, although TD with more severe clinical psychopathology could be a phenotype.

CONCLUSIONS

The schizophrenia patients with TD had significantly reduced gray matter, mostly at the bilateral inferior frontal gyrus and the right superior frontal gyrus, which correlated with severity of clinical symptoms and involuntary movement, respectively.

Tardive dyskinesia in schizophrenia

Sarró et al report grey matter deficits associated with tardive dyskinesia in schizophrenia. Much evidence suggests that the intrinsic pathophysiology of schizophrenia contributes to predisposition to tardive dyskinesia. The possibility that antipsychotics might play a causal role in the grey matter deficits cannot be excluded, but the evidence is tenuous.