The Clinical and Economic Burden of Tardive Dyskinesia in Israel: Real-World Data Analysis.

PURPOSE/BACKGROUND: Tardive dyskinesia (TD) is a hyperkinetic movement disorder caused by exposure to dopamine-receptor blockers. Data on TD burden in Israel are scarce. This analysis assesses the clinical and economic burden of TD in Israeli patients. METHODS/PROCEDURES: This retrospective analysis used a national health plan database (Maccabi Healthcare Services), representing 25% of the Israeli population. The study included adults alive at index date with an International Classification of Diseases, Ninth Revision, Clinical Modification TD diagnosis before 2018 and more than or equal to 1-year enrollment before diagnosis. Tardive dyskinesia patients were matched to non-TD patients (1:3) by underlying psychiatric condition, birth year, and sex. Treatment patterns and 2018 annual health care resource utilization and costs were assessed. FINDINGS/RESULTS: Of 454 TD patients alive between 2013 and 2018, 333 alive on January 1, 2018, were matched to 999 non-TD patients. At baseline, TD patients had lower socioeconomic status and higher proportion of chronic kidney disease and antipsychotic medication use; all analyses were adjusted accordingly. Tardive dyskinesia patients had significantly more visits to general physicians, neurologists, psychiatrists, physiotherapists, and emergency departments versus non-TD patients (all P < 0.05). Tardive dyskinesia patients also had significantly longer hospital stays than non-TD patients ( P = 0.003). Total healthcare and medication costs per patient were significantly higher in the TD versus non-TD population (US $11,079 vs US $7145, P = 0.018). IMPLICATIONS/CONCLUSIONS: Israeli TD patients have higher clinical and economic burden than non-TD patients. Understanding real-world health care resource utilization and costs allows clinicians and decision makers to quantify TD burden and prioritize resources for TD patients' treatment.

Clinical Phenotype of Tardive Dyskinesia in Bipolar Disorder.

PURPOSE: Recognizing the negative impact that antipsychotic-induced movement disorders have on the quality of life and treatment outcomes in bipolar disorder (BD), this study aimed to assess clinical correlates and antipsychotic use patterns of tardive dyskinesia (TD+) in BD. MATERIALS AND METHODS: Participants with and without TD were included. Clinical variables were compared using t-test and χ2 test. Antipsychotic use patterns in TD+, including number of trials, mean doses, and estimated cumulative exposure, were assessed in a case-only analysis. RESULTS: The prevalence rate of TD was 5.1%. In comparison to the TD- group (n = 1074), TD+ participants (n = 58) were older, more likely to be female and have type I bipolar illness. There were 60.3% of the TD+ group that continued using antipsychotics at study entry and had a mean cumulative exposure to antipsychotics of 18.2 ± 15.6 years. Average dose, in haloperidol equivalents, was 5.9 ± 3.5 mg and 77.7% of the trials were second-generation antipsychotics. CONCLUSIONS: This study confirms previously identified TD risk factors, such as age, sex, and bipolar subtype in a large BD cohort. Limitations included a cross-sectional design and the lack of tardive illness severity assessment. As atypical antipsychotics continue to be primary mood stabilization treatment, attempting to harmonize large data sets to identify additional biomarkers of tardive risk will optimize individualized care for patients with BD.

RE-KINECT: A Prospective Study of the Presence and Healthcare Burden of Tardive Dyskinesia in Clinical Practice Settings.

PURPOSE/BACKGROUND: RE-KINECT (NCT03062033) was designed to assess the presence and impact of possible tardive dyskinesia (TD) in antipsychotic-treated outpatients. METHODS/PROCEDURES: The study included adults with 3 or more months of lifetime antipsychotic exposure and 1 or more psychiatric disorder. Based on clinician observation and assessment, patients were assigned to cohort 1 (without involuntary movements or with non-TD involuntary movements) or cohort 2 (with involuntary movements confirmed by clinician as possible TD). Baseline assessments included the following: patient characteristics; location/severity of involuntary movements; and impact of possible TD on health-related quality of life, including the EuroQoL 5-Dimensions 5-Level questionnaire. FINDINGS/RESULTS: Of 739 eligible patients, 204 (27.6%) had clinician-confirmed possible TD (cohort 2). Compared with cohort 1, patients in cohort 2 were significantly older (P < 0.0001), more likely to have schizophrenia or schizoaffective disorder (P < 0.0001) and longer lifetime exposure to antipsychotics (P < 0.0001), and less likely to be working or studying, based on clinician perception (P = 0.0010). Clinician- and patient-rated severity of possible TD movements was significantly correlated in each of 4 body regions (head/face, neck/trunk, upper extremities, lower extremities), for maximum severity in any region, and for total number of affected regions (P < 0.001 for all correlations). For the patient-rated EuroQoL 5-Dimensions 5-Level, the health state visual analog scale score was significantly lower (worse) in cohort 2 versus cohort 1 (66.8 vs 69.7; P = 0.0002), as was the utility index score (0.71 vs 0.76; P < 0.0175). IMPLICATIONS/CONCLUSIONS: Results from this real-world population indicate that TD occurs frequently and can significantly reduce quality of life in patients with a psychiatric disorder.

Cumulative Burden of Illness in Veterans With Tardive Dyskinesia and Serious Mental Disorders.

PURPOSE/BACKGROUND: To inform cost-benefit decisions for veterans, the risk of tardive dyskinesia (TD) and its impact on comorbidities and outcomes were assessed. METHODS/PROCEDURES: In a retrospective study, veterans with schizophrenia/schizoaffective, and bipolar and major depressive disorders receiving antipsychotics during the period October 1, 2014, to September 30, 2015, were identified. Tardive dyskinesia was determined by International Classification of Diseases, Ninth Revision, Clinical Modification codes. Correlates of TD were examined using χ or t tests. Odds ratios (ORs) and ß parameters with 95% confidence intervals (CIs) for categorical and continuous variables associated with TD were derived from a multivariate logistic and linear regression, respectively. FINDINGS/RESULTS: Among 7985 veterans, 332 (4.2%) were diagnosed as having possible TD. The odds of having TD were higher for older veterans (OR, 1.04; 95% CI, 1.03-1.05; P < 0.0001) and veterans with schizophrenia/schizoaffective disorder (OR, 1.54; 95% CI, 1.23-1.91; P < 0.0001) or diabetes (OR, 1.64; 95% CI, 1.30-2.06; P < 0.0001). Veterans with TD received more antipsychotic prescriptions (mean ± SD, 18.4 ± 30.3 vs 13.3 ± 26.4; P = 0.003) and days of supply (233.9 ± 95.4 vs 211.4 ± 102.0; P < 0.0001). They were more likely to have received 2 or more antipsychotics (27.1% vs 19.7%, P = 0.0009) and benztropine (OR, 2.25: 95% CI 1.73-2.91; P < 0.0001). Veterans with TD had a higher Charlson Comorbidity Index score (ß = 0.32; SE, 0.09; 95% CI, 0.14-0.49; P = 0.0003) and higher odds of any medical hospitalization (OR, 1.45; 95% CI, 1.07-1.95; P = 0.001). IMPLICATIONS/CONCLUSIONS: The diagnosis of possible TD was associated with older age, schizophrenia/schizoaffective disorder, medical comorbidity, and hospitalization. Tardive dyskinesia may be a marker for patients at risk of adverse health care outcomes and diminished quality of life.

The role of glutamate receptors and their interactions with dopamine and other neurotransmitters in the development of tardive dyskinesia: preclinical and clinical results.

Tardive dyskinesia is a serious, disabling, movement disorder associated with the ongoing use of antipsychotic medication. Current evidence regarding the pathophysiology of tardive dyskinesia is mainly based on preclinical animal models and is still not completely understood. The leading preclinical hypothesis of tardive dyskinesia development includes dopaminergic imbalance in the direct and indirect pathways of the basal ganglia, cholinergic deficiency, serotonin receptor disturbances, neurotoxicity, oxidative stress, and changes in synaptic plasticity. Although, the role of the glutamatergic system has been confirmed in preclinical tardive dyskinesia models it seems to have been neglected in recent reviews. This review focuses on the role and interactions of glutamate receptors with dopamine, acetylcholine, and serotonin in the neuropathology of tardive dyskinesia development. Moreover, preclinical and clinical results of the differentiated effectiveness of N-methyl-D-aspartate (NMDA) receptor antagonists are discussed with a special focus on antagonists that bind with the GluN2B subunit of NMDA receptors. This review also presents new combinations of drugs that are worth considering in the treatment of tardive dyskinesia.

High Incidence and Prevalence of Drug-Related Movement Disorders in Young Patients With Psychotic Disorders.

BACKGROUND: Drug-related movement disorders (DRMDs) reduce quality of life and contribute to medication noncompliance of patients with psychotic disorders. Little is known about the epidemiology of DRMDs in relatively young patients a few years after onset of psychosis. This is an important period to study, as the impact of the antipsychotic treatment on the long-term potentiation of the neural pathways associated with psychotic disorders and DRMDs is still minimal. This study investigated the prevalence, incidence, persistence, and clinical correlates of DRMDs in patients during their first years after disease onset. METHODS: The Genetic Risk and Outcome of Psychosis study is a longitudinal study of 1120 relatively young patients with nonaffective psychosis and a mean age and illness duration of 27 and 4 years, respectively. The following drug-related movement disorders were assessed at baseline and at the 3-year follow-up: parkinsonism, akathisia, tardive dyskinesia, and tardive dystonia. We determined prevalence, incidence, and persistence and investigated clinical correlates at and over the baseline and follow-up assessment. RESULTS: Patients' mean age and illness duration at baseline were 27.1 and 4.3 years, respectively. In 4 patients, 1 developed a DRMD over the 3-year study period. Prevalence, incidence, and persistence rates were highest for parkinsonism (32%, 21%, and 53%) followed by akathisia (9%, 5%, and 17%) and tardive dyskinesia (4%, 3%, and 20%). Significant associations were found between DRMDs and the patients' age, IQ, and psychopathology. CONCLUSIONS: The prevalence, persistence, and incidence of DRMDs in this sample were high despite the relatively young age, recent onset of the disorder, and treatment primarily with second-generation antipsychotics. These findings emphasize that screening, diagnosis, and treatment of DRMDs are still important.

Comparing the risk of tardive dyskinesia in older adults with first-generation and second-generation antipsychotics: a systematic review and meta-analysis.

OBJECTIVE: The advent of second-generation antipsychotics (SGAs) in the 1990s brought optimism that neuroleptic-induced tardive dyskinesia (TD) may become relegated to history. Whether or not this is the case remains inconclusive, and this review aims to compare the risk of TD in older adults treated with first-generation antipsychotics (FGAs) versus SGAs. METHODS: Relevant papers were sourced via a range of electronic databases, with a date range from 1957 to January 2015. Included studies used both a validated rating scale and research diagnostic criteria to report on the prevalence or incidence of TD in older adults exposed to antipsychotic medications. RESULTS: For FGAs, the prevalence estimate was 53% (95% confidence interval [CI] [39.0, 68.4]) for mild TD and 38% (95% CI [25.9, 50.3]) for probable TD. Incidence estimates for probable TD with FGAs were 23% (95% CI [15.3, 30.6]) at 1 year, 42% (95% CI [24.8, 58.4]) at 2 years and 57% (95% CI [45.3, 69.1]) at 3 years. For SGAs, the incidence estimates at 1 year were 7% (95% CI [4.4, 10.2]) for probable TD and 3% (95% CI [1.5, 4.2]) for persistent TD. CONCLUSIONS: The risk of probable TD is more than three times lower in older adults receiving SGAs in comparison with FGAs after 1 year of treatment (23% vs 7%). The risk of persistent TD at 1 year with SGAs is particularly low. Evidence is lacking in regard to the longer-term risk of TD with SGAs, although the rates associated with the prolonged use of FGAs are high. Caution is therefore still required, particularly with the protracted use of both FGAs and SGAs.

A descriptive analysis of spontaneous reports of antipsychotic-induced tardive dyskinesia and other extrapyramidal symptoms in the Japanese Adverse Drug Event Report database.

AimThe aim of this study is to summarize the spontaneous reports of tardive dyskinesia (TD) and extrapyramidal symptoms (EPSs) that occurred in Japan over the past decade. MethodsThe study analyzed TD and EPS cases reported in the Japanese Adverse Drug Event Report database between April 2011 and March 2021. The cases were stratified by the diagnoses of schizophrenia, bipolar disorders, and depressive disorders. ResultsIn total, 800 patients including a total of 171 TD cases and 682 EPS cases were reported in the JADER database across psychiatric diagnosis. The cases were caused by first-generation antipsychotics (FGA, TD: n = 105, EPS: n = 245) and second-generation antipsychotics (SGA, TD: n = 144, EPS: n = 598). The SGA were categorized based on Neuroscience-based Nomenclature (NbN) regarding pharmacological domain and mode of action, which were reported evenly as the offending agents. Among reported treatment and outcome in TD cases (n = 67, 37.6%) and EPS cases (n = 405, 59.3%), the relatively limited number of TD cases were reported as recovered/improved was also limited (n = 32, 47.8%) compared to those of EPS cases (n = 266, 65.7%). Some cases still had residual symptoms or did not recover fully (TD: n = 21, 31.3%, EPS: n = 77, 19.0%). CONCLUSION: Tardive dyskinesia and EPS have been widely reported in Japan over the past decade across psychiatric diagnoses and antipsychotic classes. LIMITATIONS: It is important to acknowledge the presence of reporting bias and the lack of comparators to accurately assess risks. Owing to the nature of spontaneous reporting, the estimation of prevalence is not feasible.

Impact of tardive dyskinesia on patients and caregivers: a survey of caregivers in the United States.

BACKGROUND: Tardive dyskinesia (TD) has a multidimensional impact on patients with TD and, as importantly, their caregivers. An online survey was developed and administered to assess patient and caregiver burden of TD. Survey participants were unpaid caregivers for patients with diagnoses of TD and schizophrenia, bipolar disorder, and/or major depressive disorder. Overall, 162 caregivers rated the 7-day impact of TD on the physical, psychological, and social functioning of patients and the impact of TD on these domains in their own lives and in their professional lives. RESULTS: Across physical, psychological, and social domains, most caregivers (82.7%) reported that TD had severe impact on the cared-for patients, and 23.5% reported severe impact of TD in their own lives. Caregivers experienced 46.4% activity impairment, and caregivers who were employed (n = 136) experienced 49.5% overall work impairment because of TD-related caregiving. CONCLUSIONS: These results suggest that TD imposes substantial burden for both caregivers and patients.

[Idiopathic (Oral) and Tardive Dyskinesia: Pathogenesis, Epidemiology, and Treatment].

Etymologically, dyskinesia is a combination of the prefix "dys-," which means 'abnormality' and the suffix "-kinesia," which means 'movement.' In a broad sense, dyskinesia indicates hyperkinetic involuntary movements. In a narrow sense, as a general term, dyskinesia refers to combinations of one or more of the following movements: chorea, dystonia, tremor, ballism, athetosis, tics, and myoclonus. In this article, we describe the pathogenesis, epidemiology, and treatment of idiopathic (oral) and tardive dyskinesia.

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.

Correlation of Blood Biochemical Markers with Tardive Dyskinesia in Schizophrenic Patients.

Objective: Oxidative stress factors and proinflammatory cytokines had been found to be involved in the pathogenesis of patients with tardive dyskinesia (TD). This study assumes that blood biochemical markers would have a link with TD in schizophrenia patients. To explore the correlation between blood biochemical markers and tardive dyskinesia in patients with schizophrenia (SCH). Methods: From January 2010 to August 2021, the inpatients who met the diagnostic criteria of schizophrenia in the Chinese Classification and Diagnosis Criteria of Mental Disorders (DSM-4) and the American Diagnostic and Statistical Manual of Mental Disorders (DSM-4) were followed up in the psychiatric outpatient department of Jinxia Street Community Health Service Center, Longhu District, Shantou City. The diagnostic criteria of Abnormal Involuntary Movement Scale (AIMS) used in the TD study of Schooler and Kane were used to screen the patients. Patients were divided into the schizophrenia (SCH group) and the schizophrenia with TD groups (TD group). Oxidative stress factors including Superoxide Dismutase1 (SOD1), Glutathione Peroxidase1 (GPX1), Malondialdehyde1 (MDA1), Catalase Activity1 (CAT1), and brain-derived neurotrophic factor 1 (BDNF1) and some inflammatory cytokines including interleukin-2 (IL-2), interleukin-6 (IL-6), interleukin-8 (IL-8), serum tumor necrosis factor (TNF-α), prolactin, estrogen, and cortisol were measured in 121 schizophrenic patients with tardive dyskinesia and 118 schizophrenic patients. The correlation analysis was conducted on the data. Results: Age and female were immutable risk factors for the development of TD, and there were significant differences in blood biochemical indices GPX1, MDA1, CAT1, and TNF-α in schizophrenic patients with and without TD. Conclusion: This study supports that oxidative stress and immune disorders are associated with TD patients. Blood biochemical markers GPX1, MDA1, CAT1, and TNF-α may play an important role in the pathogenesis of schizophrenia combined with TD patients, and they may be useful in the diagnosis of schizophrenia with tardive dyskinesia.

Prevalence of Tardive Dyskinesia in an Electronic Medical Record Study at a Large Community Mental Health Treatment Center.

Objective: To determine the prevalence of tardive dyskinesia (TD) identified by clinicians in naturalistic data in a real-world treatment setting.Methods: Electronic medical record data were analyzed from a single large community mental health treatment center for all psychiatric provider encounters of 120,431 unique adult and child patients during a 5-year period from January 2013 through December 2017, focusing on clinician-identified TD in patients prescribed antipsychotic medication.Results: Only half of the antipsychotic-prescribed patients had Abnormal Involuntary Movement Scale (AIMS) information recorded in their medical records, and only 1% of those with AIMS data had a positive AIMS identifying TD. AIMS testing represented the largest source of all identified TD in these patients, but only one-third of the patients with a positive AIMS in the record had a clinical diagnosis of TD recorded in the prescriber's diagnostic impression list from billing code data. The clinical identification of only 1% of antipsychotic-prescribed patients with TD in this study is far below generally established TD prevalence estimates of previous research. An important methodological contributor to this discrepancy is generation of the data by treating clinicians in this study who greatly under identified TD relative to systematic research methodology.Conclusions: Given the recent availability of US Food and Drug Administration-approved pharmaceutical agents for treatment of TD, it is now more important than ever to identify and intervene in TD. Agency-wide policies and procedures can be established to ensure that TD assessments are systematically conducted with regularity and accuracy among all antipsychotic-prescribed patients.

Tardive Dyskinesia and Long-Acting Injectable Antipsychotics: Analyses Based on a Spontaneous Reporting System Database in Japan.

Objective: This study compared the reporting frequency of tardive dyskinesia (TD) between long-acting injectable antipsychotics (LAI-APs) and the equivalent oral antipsychotics (O-APs), LAI first-generation antipsychotics (LAI-FGAs) and LAI second-generation antipsychotics (LAI-SGAs), and individual LAI-APs.Methods: The Japanese Adverse Drug Event Report was used in this study, and data were obtained from April 2004 to February 2021. Patients who received LAI-APs available in Japan (LAI haloperidol, LAI fluphenazine, LAI aripiprazole, LAI risperidone, and LAI paliperidone) or the equivalent O-APs were included in this study. We calculated the adjusted reporting odds ratios (aRORs) to compare the reporting frequency of TD.Results: A total of 8,425 patients were included in the study. TD was reported significantly less frequently with LAI paliperidone than with oral paliperidone (aROR [95% confidence interval (CI)] = 0.13 [0.05-0.36]). Other LAI-APs were associated with a numerically lower reporting frequency of TD than the equivalent oral SGAs. The reporting frequency of TD associated with LAI-SGAs was significantly lower than that of LAI-FGAs (aROR [95% CI] = 0.18 [0.08-0.43]). All LAI-SGAs were significantly associated with a lower reporting frequency of TD than that of LAI fluphenazine (aROR [95% CI]: LAI aripiprazole, 0.11 [0.04-0.35]; LAI risperidone, 0.09 [0.03-0.32]; LAI paliperidone, 0.02 [0.005-0.09]). and LAI haloperidol, 8.58 [1.85-39.72]). LAI fluphenazine was significantly associated with a higher reporting frequency of TD than LAI haloperidol (aROR [95% CI] = 8.58 [1.85-39.72]). The reporting frequency of TD associated with LAI paliperidone was significantly lower than that with LAI aripiprazole (aROR [95% CI] = 0.18 [0.05-0.73]).Conclusions: Compared to O-APs, LAI-APs, particularly LAI-SGAs, may be associated with a lower risk of TD.

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.

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.

Assesment of Risk Factors for Tardive Dyskinesia.

Objective: Aim of the study is to evaluate sociodemographic and clinical features that may be associated with the development of Tardive dyskinesia (TD). Methods: 80 patients attending an outpatient psychiatry clinic in Istanbul, Turkey were divided into TD (n = 50) and control groups (CG) (n = 30). Sociodemographic and clinical data was collected through face-to-face interviews and a retrospective search of medical records. Results: There was a significant difference between TD and control group (CG) in terms of mean; onset of psychiatric disease at or after 35 years of age; first use of APD at or after 35 years of age; use of long-acting injectable APD; history of extrapyramidal side-effects; history of akathisia and family history of psychiatric disease. There was no significant difference between the two groups in terms of DSM- IV-based psychiatric diagnosis distributions, the existence of complete recovery periods during the course of the disease; total duration of APD use for at least 10 years; APD holidays; regular APD use; history of ECT and smoking or alcohol and substance abuse/addiction. Conclusion: Advancing age seemed to be the most significant risk factor in the development of TD. Clinicians need to be cautious about TD when prescribing APD for elderly patients.

Liver enzyme CYP2D6 gene and tardive dyskinesia.

Background: Tardive dyskinesia (TD) is an iatrogenic involuntary movement disorder occurring after extended antipsychotic use with unclear pathogenesis. CYP2D6 is a liver enzyme involved in antipsychotic metabolism and a well-studied gene candidate for TD. Materials & methods: We tested predicted CYP2D6 metabolizer phenotype with TD occurrence and severity in our two samples of European chronic schizophrenia patients (total n = 198, of which 82 had TD). Results: TD occurrence were associated with extreme metabolizer phenotype, controlling for age and sex (p = 0.012). In other words, individuals with either increased and no CYP2D6 activity were at higher risk of having TD. Conclusion: Unlike most previous findings, TD occurrence may be associated with both extremes of CYP2D6 metabolic activity rather than solely for poor metabolizers.

Tardive dyskinesia: Who gets it and why.

Tardive dyskinesia (TD) is a potentially permanent movement disorder resulting from chronic use of dopamine receptor blocking agents (DRBA). Identified risk factors include the type of antipsychotic agent, being greater for those of first generation antipsychotics (FGA), the duration of illness and cumulative dose of DRBA and advanced age. Female sex and African and Caucasian ethnicity are additional potential risk factors. Because only a subset of people taking DRBA's develops TD, genetics may play a role. Susceptibility gene candidates include those involved in DRBA metabolism and the targets or receptors of DRBA's. Although met with conflicting data, the following genes may be involved with TD development: the cytochrome P450 gene CYP2D6, involved with metabolism of most antipsychotics, Dopamine D2 and D3 receptor genes, serotonin 2A and 2C receptor genes, vesicular monoamine transporter 2 (VMAT 2) gene, involved with intracellular neurotransmitter packaging, and the manganese superoxide dismutase (MnSOD) gene, an antioxidant enzyme. Heparan sulfate proteoglycan 2 (HSPG 2) gene is another potential gene involved with development of TD. The pathogenesis of TD is unknown, however there are three main theories proposed: dopamine receptor supersensitivity resulting from chronic dopamine receptor blockade, oxidative stress and maladaptive synaptic plasticity each of which is discussed further in this article. Tardive dyskinesia (TD) is a potentially permanent and disabling adverse effect from certain medications. By definition TD is the insidious onset of rhythmic, repetitive, stereotypic movements of the face, mouth and tongue, often with involvement of the trunk and extremities that occur as a result of dopamine receptor blocking agents (DRBA) [1]. The term tardive refers to the delayed onset of the disorder. The mean prevalence of TD is estimated to be 25.3% in psychiatric patients taking antipsychotics [2]. Compared to the number of people taking these drugs, TD represents a minority. TD is a potentially permanent condition; stopping the offending agent does not always alleviate the condition. Therefore, prevention of TD by avoiding DRBA's if at all possible is ideal. However, there is no apparent way to predict who will develop TD and there are some cases in which DRBA's are necessary for treatment of chronic conditions. As TD has been present since the development of DRBA's, possible risk factors for its development have been studied. Solmi et al. (2018) [3] have written a comprehensive review on this subject.