Gender differences in the prevalence, risk and clinical correlates of tardive dyskinesia in Chinese schizophrenia

Tardive dyskinesia in Asia- current clinical practice and the role of neurologists in the care pathway

Tardive dyskinesia (TD) is a movement disorder that can arise as a side effect of treatment with dopamine receptor-blocking agents (DRBAs), including antipsychotic drugs (APDs) used to manage psychotic illnesses. Second-generation APDs (SGAs) are often preferred to first-generation drugs due to their lower propensity to cause TD, however many SGAs-treated patients still develop the condition. Although TD is a global health concern, evidence regarding the occurrence of TD and how it is managed in Asian countries is currently limited. This article reports the results of a systematic review of the published literature on TD focusing on its prevalence, types of patients, knowledge of the condition, causative factors, and usual treatment pathways in clinical practice in Asian countries. Epidemiological data suggest that the prevalence of TD is increasing globally due to an overall rise in APD use, contributing factors being polypharmacy with multiple APDs, the use of higher than necessary doses, and off-label use for non-psychotic indications. Although exact prevalence figures for TD in Asian countries are difficult to define, there is a similar pattern of rising APD use which will result in increasing numbers of TD patients in this region. These issues need to be addressed and strategies developed to minimize TD risk and manage this disabling condition which impacts patients' quality of life and daily functioning. To date, both research into TD has been predominantly psychiatry focused and the perspectives from neurologists regarding the clinical management of this challenging condition are scarce. However, neurologists have an essential role in managing the movement disorders manifestations that characterize TD. Optimum management of TD, therefore, should ideally involve collaboration between psychiatrists and neurologists in joint care pathways, wherever practical. Collaborative pathways are proposed in this article, and the challenges that will need to be addressed in Asian countries to improve the care of people with TD are highlighted, with a focus on the neurologist's viewpoint and the implications for the management of TD globally.

Associations between polymorphisms in the cannabinoid receptor 1 gene, cognitive impairments and tardive dyskinesia in a Chinese population with schizophrenia

OBJECTIVE

Tardive dyskinesia (TD) is a medically induced movement disorder that occurs as a result of long-term use of antipsychotic medications, commonly seen in patients with schizophrenia (SCZ). The study aimed to investigate the relationship between single nucleotide polymorphisms (SNPs) of the CNR1 gene, TD and cognitive impairments in a Chinese population with SCZ.

METHODS

A total of 216 SCZ patients were recruited. The participants were divided into TD and without TD (WTD) groups using the Schooler-Kane International Diagnostic Criteria. The severity of TD was assessed using the Abnormal Involuntary Movement Scale (AIMS). Cognitive function was assessed using the Repeatable Battery for Assessment of Neuropsychological Status (RBANS) scale. Hardy-Weinberg equilibrium tests, chained disequilibrium analyses and haplotype analyses were performed using SHE-sis software. To explore the main effects of TD diagnosis, genotype and cognitive function, as well as interaction effects, analysis of covariance (ANCOVA) was employed.

RESULTS

The prevalence of TD was approximately 27.3%. Significant differences were observed in the rs806368 CT genotype and rs806370 TC genotype within the hypercongenic pattern between the male TD and WTD groups (OR = 2.508, 95% CI: 1.055-5.961, p = 0.037; OR = 2.552, 95% CI: 1.073-6.069, p = 0.034). Among TD patients, those carrying the rs806368 CC genotype exhibited higher limb trunk scores (p < 0.05). Moreover, there was a statistically significant difference in visuospatial/construction between the TD and WTD groups (p = 0.04), and a borderline significant difference in visuospatial/construction when considering the interaction between TD diagnosis and genotype at the rs806368 locus (p = 0.05).

CONCLUSION

CNR1 rs806368 and rs806370 polymorphisms may play a role in TD susceptibility. Additionally, CNR1 gene polymorphisms were associated with the severity of involuntary movements and cognitive impairments in TD patients.

Sex difference in association between tardive dyskinesia and cognitive deficits in patients with chronic schizophrenia

BACKGROUND

Tardive dyskinesia (TD), a side effect due to long-term use of antipsychotic medication, is associated with cognitive impairment. Several studies have found sex differences in cognitive impairment in schizophrenia patients, while whether there are sex differences in cognitive performance in schizophrenia patients with TD has not been reported.

METHODS

A total of 496 schizophrenia inpatients and 362 healthy controls were recruited for this study. We used the Positive and Negative Syndrome Scale (PANSS) to assess patients' psychopathological symptoms and the Abnormal Involuntary Movement Scale (AIMS) to assess the severity of TD. Cognitive function was measured in 313 of these inpatients and 310 of healthy controls using the Repeatable Battery for Assessment of Neuropsychological Status (RBANS).

RESULTS

Patients with schizophrenia performed worse in all cognitive domains than healthy controls(all p < 0.001). Compared to patients without TD, patients with TD had higher PANSS total, PANSS negative symptom subscale and AIMS scores (all p < 0.001), while RBANS total, visuospatial/constructional and attention subscale scores were significantly lower (all p < 0.05). In addition, the visuospatial/constructional and attention indices remained significantly lower in male patients with TD than those without TD (both p < 0.05), but these results were not observed in female patients. Moreover, visuospatial/constructional and attention indices were negatively correlated with total AIMS scores only in male patients (both p < 0.05).

CONCLUSION

Our results suggest that there may be sex differences in cognitive impairment in schizophrenia patients with comorbid TD, indicating that female gender may have a protective effect on cognitive impairment in schizophrenia patients caused by TD.

Clinical determinants, patterns and outcomes of antipsychotic medication prescribing in the treatment of schizophrenia and schizoaffective disorder: A naturalistic cohort study

BACKGROUND

Schizophrenia affects individuals, families, and systems, with treatment primarily being antipsychotic medications. Long-acting injectable (LAI) antipsychotics are increasingly being used. This study sought to identify predictors of antipsychotic choice, in terms of formulation (LAI vs oral) and class (FGA vs SGA), and clinical outcomes.

METHODS

123 patients who received LAI antipsychotics were diagnosis-matched to patients who received oral antipsychotics. Sociodemographic and clinical factors were extracted from the medical record, including indicators of illness severity. Groups were compared with Chi-Square and t-tests, and logistic regression models were used to identify independent predictors of antipsychotic choice.

RESULTS

Patients that received LAIs had longer admissions, more complex discharges, and greater illness severity; however, there were no differences in readmission rates. Independent predictors of LAIs included younger age, being single, and longer admission. Patients who received FGA LAIs were more likely to use substances and be undomiciled compared to SGA LAIs, with the only predictor being older age. Oral FGAs were more likely than Oral SGAs to be prescribed to older and female patients, as well as those with co-occurring substance use, complex discharges, and longer admissions.

CONCLUSIONS

Illness severity and duration of illness appear to drive choice of LAI vs. oral antipsychotic medication and FGA vs. SGA. While LAIs were prescribed to patients with greater illness severity, readmission rates were equivalent to those receiving oral medication, supporting the use of LAI in patients with greater illness severity. Rationales for prescribing LAIs to younger patients and FGAs to older patients are discussed.

Identification of novel proteins associated with movement-related adverse antipsychotic effects by integrating GWAS data and human brain proteomes

Genome-wide association studies (GWAS) have identified some variants for movement-related adverse antipsychotic effects (MAAE), while how these variants confer MAAE remains unclear. We used the probabilistic Mendelian randomization (PMR) method to identify candidate proteins for MAAE by integrating MAAE GWASs and protein quantitative trait loci (pQTL) data. An independent pQTL data from the Banner project and brain-derived eQTL data were used to perform confirmatory PMR. A total of 56 proteins were identified as candidate targets for MAAE after false discovery rates (FDR) correction, such as GRIN2B, ADRA1A, and PED4B. 12 genes were replicated in the confirmatory PMR, and 18 genes had consistent evidence at the transcript level. Furthermore, we investigated the associations between candidate proteins and the motor symptoms of Parkinson's disease (PD). There were 24, 38, and 10 candidate proteins that were significantly associated with PD, PD motor subtypes, and PD motor progression, respectively. Enrichment analysis identified 34 GO terms and 17 pathways that may be involved in MAAE, such as glutamatergic synapse, glutamate receptor complex, and GABAergic synapse. Our study identified multiple candidate genes and pathways that were associated with MAAE, providing new insights into the biological mechanism of MAAE and targets for further mechanistic and therapeutic studies.

Tardive dyskinesia in Chinese patients with schizophrenia: Prevalence, clinical correlates and relationship with cognitive impairment

OBJECTIVE

Tardive dyskinesia (TD) has a high prevalence and is one of the distressing side effects of antipsychotic medications. Few studies have explored the relationship between TD, clinical correlates, and cognition. The aim of this study was to assess the prevalence, clinical correlates and cognitive impairment of co-occurring TD in Chinese patients with schizophrenia.

METHODS

We recruited 655 patients with chronic schizophrenia who met the DSM-IV diagnostic criteria for schizophrenia and collected clinical and demographic data. All patients were assessed using the Abnormal Involuntary Movement Scale (AIMS) for the severity of TD, Positive and Negative Syndrome Scale (PANSS) for psychopathological symptoms, and Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) for cognition.

RESULTS

The overall TD prevalence was 41.1%, 42.9% (246/574) in men and 28.4% (23/81) in women (χ2 = 6.1 df = 1, p < 0.05). There were significant differences in age, sex, duration of illness, number of hospitalizations, drug type, smoking and PANSS negative symptom subscore between TD and non-TD groups (all p < 0.05). Moreover, patients with TD scored lower for immediate memory, attention, delayed memory, and RBANS total scores (all p < 0.05). Logistic regression showed a significant correlation between TD and age, sex, drug type and attention subscore.

CONCLUSION

Our results suggest that multiple demographic and clinical variables may be associated with the development of TD. Moreover, TD patients may exhibit more cognitive impairment than non-TD patients.

Prevalence, clinical correlates and risk factors associated with Tardive Dyskinesia in Chinese patients with schizophrenia

Tardive Dyskinesia (TD) is a serious, nonrhythmic and iatrogenic movement disorder, and is a common comorbidity in patients with schizophrenia (SZ). The main goal of this study was to investigate the prevalence, clinical correlates, and risk factors of TD in Chinese patients with chronic SZ, which has not been fully studied. This study adopted a cross-sectional design. A total of 901 Chinese inpatients with SZ were recruited between 2008 and 2011. We used the Abnormal Involuntary Movement Scale (AIMS) to measure the severity of TD, and the Positive and Negative Syndrome Scale (PANSS) was used to measure the psychopathological symptoms of SZ. Blood samples were also collected for routine blood tests, including the levels of triglyceride (TG), cholesterol (CHO), HDL-cholesterol (HDL-CHO), LDL-cholesterol (LDL-CHO), Apolipoprotein A1 (ApoA1), and Apolipoprotein B (ApoB). Overall, 36% of patients with SZ had TD. Compared with the non-TD patients, the TD patients were more likely to be men, had older age, lower education level, higher smoking rate, higher hospitalization frequency, and longer duration of illness (DOI). Further, compared with the non-TD patients, the TD patients had higher PANSS total, PANSS negative subscale, and cognitive subscale scores, but had lower depressive subscale scores and lower mean levels of metabolic biomarkers, including TG, CHO, HDL-CHO, LDL-CHO, ApoA1 and ApoB. Moreover, binary regression analysis showed that antipsychotic type, BMI, gender, age, HDL-CHO, and ApoB were associated with TD. Our findings indicate that TD is a common movement disorder in patients with chronic SZ, with certain demographic and clinical variables being risk factors for the development of TD.

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.

Antipsychotic-induced tardive dyskinesia: update on epidemiology and management

PURPOSE OF REVIEW

To provide an update on the frequency of antipsychotic-induced tardive dyskinesia and its management in patients with schizophrenia spectrum disorders in studies published since the last systematic review in 2008.

RECENT FINDINGS

Recent data about antipsychotic-induced tardive dyskinesia in patients with schizophrenia underscore the superiority of newer generation antipsychotics (21%) over first-generation antipsychotics (30%) with respect to prevalence and incidence rates. Regarding recently tested management strategies, the new vesicular monoamine transporter 2 inhibitors valbenazine and deutetrabenazine have been found to be effective and may be considered as first-line pharmacotherapy for tardive dyskinesia. Owing to quality issues of randomized controlled trials and/or small sample sizes, limited and conflicting evidence remains for most treatment strategies.

SUMMARY

The reviewed literature reveals lower prevalence rates of antipsychotic-induced tardive dyskinesia in patients treated with newer generation compared with first-generation antipsychotics. The evidence of vesicular monoamine transporter 2 inhibitors as a first-line therapy for tardive dyskinesia is well supported by several controlled clinical trials.

Treatment of Tardive Dyskinesia: A General Overview with Focus on the Vesicular Monoamine Transporter 2 Inhibitors

Tardive dyskinesia (TD) encompasses the spectrum of iatrogenic hyperkinetic movement disorders following exposure to dopamine receptor-blocking agents (DRBAs). Despite the advent of atypical or second- and third-generation antipsychotics with a presumably lower risk of complications, TD remains a persistent and challenging problem. Prevention is the first step in mitigating the risk of TD, but early recognition, gradual withdrawal of offending medications, and appropriate treatment are also critical. As TD is often a persistent and troublesome disorder, specific antidyskinetic therapies are often needed for symptomatic relief. The vesicular monoamine transporter 2 (VMAT2) inhibitors, which include tetrabenazine, deutetrabenazine, and valbenazine, are considered the treatment of choice for most patients with TD. Deutetrabenazine-a deuterated version of tetrabenazine-and valbenazine, the purified parent product of one of the main tetrabenazine metabolites, are novel VMAT2 inhibitors and the only drugs to receive approval from the US FDA for the treatment of TD. VMAT2 inhibitors deplete presynaptic dopamine and reduce involuntary movements in many hyperkinetic movement disorders, particularly TD, Huntington disease, and Tourette syndrome. The active metabolites of the VMAT2 inhibitors have high affinity for VMAT2 and minimal off-target binding. Compared with tetrabenazine, deutetrabenazine and valbenazine have pharmacokinetic advantages that translate into less frequent dosing and better tolerability. However, no head-to-head studies have compared the various VMAT2 inhibitors. One of the major advantages of VMAT2 inhibitors over DRBAs, which are still being used by some clinicians in the treatment of some hyperkinetic disorders, including TD, is that they are not associated with the development of TD. We also briefly discuss other treatment options for TD, including amantadine, clonazepam, Gingko biloba, zolpidem, botulinum toxin, and deep brain stimulation. Treatment of TD and other drug-induced movement disorders must be individualized and based on the severity, phenomenology, potential side effects, and other factors discussed in this review.

Management of common adverse effects of antipsychotic medications

The benefits of antipsychotic medications are sometimes obscured by their adverse effects. These effects range from relatively minor tolerability issues (e.g., mild sedation or dry mouth) to very unpleasant (e.g., constipation, akathisia, sexual dysfunction) to painful (e.g., acute dystonias) to disfiguring (e.g., weight gain, tardive dyskinesia) to life-threatening (e.g., myocarditis, agranulocytosis). Importantly, adverse effect profiles are specific to each antipsychotic medication and do not neatly fit into first- and second-generation classifications. This paper reviews management strategies for the most frequent side effects and identifies common principles intended to optimize net antipsychotic benefits. Only use antipsychotics if the indication is clear; only continue antipsychotics if a benefit is discernible. If an antipsychotic is providing substantial benefit, and the adverse effect is not life-threatening, then the first management choice is to lower the dose or adjust the dosing schedule. The next option is to change the antipsychotic; this is often reasonable unless the risk of relapse is high. In some instances, behavioral interventions can be tried. Finally, concomitant medications, though generally not desirable, are necessary in many instances and can provide considerable relief. Among concomitant medication strategies, anticholinergic medications for dystonias and parkinsonism are often effective; beta-blockers and anticholinergic medications are useful for akathisia; and metformin may lead to slight to moderate weight loss. Anticholinergic drops applied sublingually reduce sialorrhea. Usual medications are effective for constipation or dyslipidemias. The clinical utility of recently approved treatments for tardive dyskinesia, valbenazine and deutetrabenazine, is unclear.

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.

New findings in pharmacogenetics of schizophrenia

PURPOSE OF REVIEW

This review highlights recent advances in the investigation of genetic factors for antipsychotic response and side effects.

RECENT FINDINGS

Antipsychotics prescribed to treat psychotic symptoms are variable in efficacy and propensity for causing side effects. The major side effects include tardive dyskinesia, antipsychotic-induced weight gain (AIWG), and clozapine-induced agranulocytosis (CIA). Several promising associations of polymorphisms in genes including HSPG2, CNR1, and DPP6 with tardive dyskinesia have been reported. In particular, a functional genetic polymorphism in SLC18A2, which is a target of recently approved tardive dyskinesia medication valbenazine, was associated with tardive dyskinesia. Similarly, several consistent findings primarily from genes modulating energy homeostasis have also been reported (e.g. MC4R, HTR2C). CIA has been consistently associated with polymorphisms in the HLA genes (HLA-DQB1 and HLA-B). The association findings between glutamate system genes and antipsychotic response require additional replications.

SUMMARY

The findings to date are promising and provide us a better understanding of the development of side effects and response to antipsychotics. However, more comprehensive investigations in large, well characterized samples will bring us closer to clinically actionable findings.

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

INTRODUCTION

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

Association between DBH 19bp insertion/deletion polymorphism and cognition in schizophrenia with and without tardive dyskinesia

Long-term antipsychotic treatment for schizophrenia is associated with the development of tardive dyskinesia (TD), which is involved in increased cognitive impairment. Dopamine beta-hydroxylase (DBH) gene associated with dopamine and norepinephrine systems influences cognition. Schizophrenia with TD have higher DBH activity than those without TD. This study examined whether DBH5'-insertion/deletion (-Ins/Del) polymorphism could influence cognitive function in schizophrenia with and without TD. The presence of DBH5'-Ins/Del polymorphism was determined in 345 schizophrenia with TD and 397 schizophrenia without TD. The Abnormal Involuntary Movement Scale and Repeatable Battery for Assessment of Neuropsychological Status (RBANS) were used to assess TD severity and cognition. The allele and genotype frequencies of DBH5'-Ins/Del polymorphism did not differ between patients with and without TD (both p>0.05). RBANS total score and subscales did not differ by DBH5'-Ins/Del genotype groups in patients with TD (all p>0.05). However, attention score significantly differed by DBH5'-Ins/Del genotype groups in those without TD (p<0.05). Patients without TD who were Del homozygous had significantly lower attention score than those without TD who were Ins alleles (p<0.05). Immediate memory and attention scores were lower in patients with TD than without TD (both p<0.05). This study indicated that DBH5'-Ins/Del polymorphism may not play a role in the susceptibility to TD and cognitive deficits in schizophrenia with TD, but it may influence cognitive function in schizophrenia with non-TD. Moreover, schizophrenia with TD experienced greater cognitive deficits than those with non-TD, especially in immediate memory and attention.

Pharmacogenetics of tardive dyskinesia: an updated review of the literature

Tardive dyskinesia (TD) is a serious and potentially irreversible side effect of long-term exposure to antipsychotic medication characterized by involuntary trunk, limb and orofacial muscle movements. Various mechanisms have been proposed for the etiopathophysiology of antipsychotic-induced TD in schizophrenia patients with genetic factors playing a prominent role. Earlier association studies have focused on polymorphisms in CYP2D6, dopamine-, serotonin-, GABA- and glutamate genes. This review highlights recent advances in the genetic investigation of TD. Recent promising findings were obtained with the HSPG2, DPP6, MTNR1A, SLC18A2, PIP5K2A and CNR1 genes. More research, including collection of well-characterized samples, enhancement of genome-wide strategies, gene–gene interaction and epigenetic analyses, is needed before genetic tests with clinical utility can be made available for TD.

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.

Tardive dyskinesia is associated with greater cognitive impairment in schizophrenia

OBJECTIVE

Schizophrenia is a psychiatric disorder diagnosed by the presence of a number of symptoms with cognitive impairment as a core feature. Long-term antipsychotic treatment is often associated with the emergence of tardive dyskinesia (TD) and the presence of TD is linked to cognitive impairment. This study examined the relationship between TD and cognitive deficits in Chinese patients with schizophrenia.

METHODS

We recruited 206 chronic patients with TD (n=102) and without TD (n=104) meeting DSM-IV criteria for schizophrenia and 104 control subjects who were matched on age, gender, and education. All the patients completed the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), Positive and Negative Symptom Scale (PANSS), and the Abnormal Involuntary Movement Scale (AIMS).

RESULTS

The PANSS total score (p=0.01), N subscore (p=0.006), and AIMS total score (p<0.001) were significantly higher in patients with TD compared to patients without TD. Patients with TD scored lower for visuospatial/constructional, attention, and total index scores (all p<0.001) on the RBANS. AIMS orofacial scores were identified as an independent contributor to RBANS total scores and attention index (p<0.05), whereas AIMS limb and truncal scores were an independent determinant to the visuospatial/constructional index of RBANS (p<0.05).

CONCLUSION

TD was associated with greater cognitive impairment in patients with schizophrenia compared to those without TD. The orofacial and limb-trunk TD specifically appeared to be a risk factor or contributor to the different aspects of cognitive deficits in schizophrenia. The association between schizophrenia and TD may be explained in part by oxidative stress.

Association of the dopamine β-hydroxylase 19 bp insertion/deletion polymorphism with positive symptoms but not tardive dyskinesia in schizophrenia

OBJECTIVE

Overactivity of dopaminergic neurotransmission is a putative mechanism of tardive dyskinesia (TD). Dopamine beta-hydroxylase (DBH) is a key enzyme in the conversion of dopamine to norepinephrine, and plasma DBH activity is altered in TD patients. This study examined whether the functional DBH 5'-Ins/Del polymorphism was associated with TD severity in Chinese patients with schizophrenia.

METHODS

We compared the rate of this polymorphism in patients with (n = 312) and without TD (n = 435), and healthy controls (n = 625). The severity of TD was assessed using the Abnormal Involuntary Movement Scale (AIMS) and psychopathology using the Positive and Negative Syndrome Scale (PANSS).

RESULTS

There were no significant differences in the distribution of the allele and genotype frequencies between the patients and controls, or between the patients with and without TD. Also, there was no significant difference in the AIMS total score between the three genotype groups. However, the PANSS positive symptom subscore was significantly higher in patients with Del/Del genotype (13.2 ± 5.2) than those with Ins/Del (11.2 ± 4.9) and Ins/Ins (11.1 ± 3.1) genotypes (both p < 0.05).

CONCLUSION

These results suggest that although the DBH 5'-Ins/Del polymorphism was not associated with susceptibility to TD in patients with schizophrenia, it might be related to positive symptoms of schizophrenia.

Intramuscular ziprasidone versus haloperidol for managing agitation in Chinese patients with schizophrenia

Intramuscular (IM) antipsychotics are preferred for efficient control of agitation symptoms. Previous studies have demonstrated that IM ziprasidone is efficacious and safe for treatment of agitation in schizophrenia. However, clinicians now recognize that racial differences may contribute to altered therapeutic response and tolerability. This study compared the efficacy and tolerability of IM ziprasidone versus IM haloperidol for the management of agitation in Chinese subjects with schizophrenia. Subjects with acute schizophrenia were randomized to either ziprasidone (n = 189, 10 to 20 mg as required up to a maximum of 40 mg/d) or haloperidol (n = 187, 5 mg every 4 to 8 hours to a maximum of 20 mg/d) for 3 days. Psychiatric assessments and adverse events were assessed at baseline, 2, 4, 24, 48, and 72 hours. In the ziprasidone group, 2.1% of subjects discontinued versus 3.7% in the haloperidol group. The least squares mean change (SE) from baseline to 72 hours in Brief Psychiatry Rating Scale total score was -17.32 (0.7) for ziprasidone (n = 167) and -18.44 (0.7) for haloperidol (n = 152), with a 95% confidence interval treatment difference of -0.7 to 2.9. Fewer subjects experienced adverse events after ziprasidone (n = 54, 28.6%) than haloperidol (n = 116, 62.0%), with a notably higher incidence of extrapyramidal symptoms in the haloperidol group (n = 69, 36.9%) compared to the ziprasidone group (n = 4, 2.1%). For controlling agitation in schizophrenia in this Chinese study, ziprasidone had a favorable tolerability profile and comparable efficacy and safety compared to haloperidol.

Rater evaluations for psychiatric instruments and cultural differences: the positive and negative syndrome scale in China and the United States

This article compares Positive and Negative Syndrome Scale (PANSS) data from Chinese and American inpatients with chronic schizophrenia to show how differences in item ratings may reflect cultural attitudes of raters. The Chinese sample (N = 504) came from Beijing Huilongguan Hospital. The American sample came from 268 PANSS assessments of Clinical Antipsychotic Trials of Intervention Effectiveness subjects hospitalized for 15 days or more to optimize equivalence of the samples. When controlling for age and sex, the Chinese sample scored significantly lower for total score by 25% (p < 0.0001), for the positive subscale by 35% (p < 0.0001), and on the general subscale by 32% (p < 0.0001) but not significantly different on the negative subscale score (+0.26%; p = 0.76). However, the Chinese sample scored 26% higher on the item on poor rapport (p < 0.0001), 10.2% higher on passive social withdrawal (p = 0.003), and most notably 46% higher on the item on lack of judgment and insight (p < 0.0001). These results remain broadly consistent across sex subgroup analyses. Differences seem to be best explained by both cultural differences in patient clinical presentations and varying American and Chinese cultural values affecting rater judgment.

Comparing the PANSS in Chinese and American inpatients: cross-cultural psychiatric analyses of instrument translation and implementation

This article compares data from the Positive and Negative Syndrome Scale (PANSS) collected from Chinese and American inpatients diagnosed with schizophrenia to show how patterned differences in item ratings may reflect cultural attitudes of the raters. The Chinese sample (N=553) was based on consecutive admissions to four academic hospitals in Changsha, China. Only patients ill for 3 or more years were included in the analysis to match the chronically ill sample represented in the US CATIE sample. A total of 261 PANSS assessments were completed during a month when CATIE subjects had been hospitalized for 15 days or more to optimize equivalence of the US and Chinese samples. Controlling for age and gender, the total PANSS and the three sub-scores were all significantly lower in the Chinese than in the US CATIE sample by 5-8% (all p<.05). However, on 9 items, the Chinese sample scored 10-30% higher than the US sample (all p<.05) and on 5 items they scored over 20% higher (all p<.0001). These items rated increased hostility, poorer attention, lack of judgment and insight, disturbance of volition, and poorer impulse control. We ascribe these differences to cultural variations in the ways individuals relate to others in their social environment within Chinese and American societies.

Gender differences in antipsychotic prescribing

OBJECTIVE

Optimum outcome for those with psychosis will necessarily involve treatment with antipsychotic medication. Unfortunately this medication is associated with a high rate of adverse effects and as a consequence non-adherence. Maximizing symptomatic relief whilst minimizing side effects is the aim of treatment. In order to do this adequately prescribers need to be aware of the significant differences between men and women in response to antipsychotic treatment. These differences are not simply biologically mediated; both physiological and sociocultural factors contribute.

METHOD

Findings from a variety of sources were used to summarize gender differences in antipsychotic treatment.

RESULTS

Pharmacokinetic and pharmacodynamic factors, the impact of reproductive phases in women and gender differences in antipsychotic prescription across the lifespan (from children and adolescents to the elderly) are discussed. Important ethnic and racial differences are also mentioned.

CONCLUSION

Women require less antipsychotic medication than men to achieve a better symptom response, but this is at the expense of a higher side effect burden, in particular hormonal and metabolic side effects. Children, adolescents and the elderly are at especially high risk of adverse reactions with antipsychotics. In order to optimize outcome in people with psychosis, prescribers should ensure that gender differences are taken into account.

Phosphodiesterase 4B genetic variants are not associated with antipsychotic-induced tardive dyskinesia

Phosphodiesterase 4B (PDE4B) has been evaluated as a genetic risk factor for schizophrenia. Selective PDE4 inhibitor drugs have antipsychotic-like effects and reduce tardive dyskinesia-like movements in animal models. We investigated whether PDE4B genetic variants are associated with antipsychotic-induced tardive dyskinesia incidence and severity in schizophrenia patients. Our sample consisted of 169 Caucasian patients taking typical antipsychotic medication for at least 1 year. We found two PDE4B gene variants to be nominally associated with tardive dyskinesia (rs1338719 and rs7528545) in the overall population and two other variants nominally associated with the presence of tardive dyskinesia and severity in female patients (rs1890196 and rs783036). None of these results survived correction for multiple testing. Overall, our results do not support a genetic association between tardive dyskinesia and PDE4B.

The catechol-O-methyl-transferase gene in tardive dyskinesia

Tardive dyskinesia (TD) is a severe and potentially irreversible motor side effect linked to long-term antipsychotic exposure. Changes in dopamine neurotransmission have been implicated in the etiology of TD, and catechol-O-methyl-transferase (COMT) is an enzyme that metabolizes dopamine.

OBJECTIVES

We investigated five single-nucleotide polymorphisms in addition to the functional Val158Met variant spanning the COMT gene for association with TD.

METHODS

We analyzed the six COMT single-nucleotide polymorphisms in a sample of schizophrenia/schizoaffective disorder patients (n=226; 196 Caucasians and 30 African Americans).

RESULTS

We found a significant association between the marker rs165599 in the 3' untranslated region of COMT and TD (AA versus G-carrier: OR(AA)=2.22, 95% CI:1.23-4.03; P=0.007). The association appeared to be originating from males. We did not find a significant association of the other five tested polymorphisms with TD in our samples. We performed a sex-stratified meta-analysis across all of the published studies (n=6 plus our own data) of COMT and TD, and found an association between ValVal genotype and TD in females (OR(ValVal)=1.63, 95% CI: 1.09-2.45; P=0.019) but not in males.

CONCLUSIONS

Overall, our results suggest that the COMT gene may have a minor but consistent role in TD, although sex-stratified studies with additional markers in larger clinical samples should be performed.