Prospective study of tardive dyskinesia in the elderly: rates and risk factors

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.

Movement disorders of the mouth: a review of the common phenomenologies

Movement disorders of the mouth encompass a spectrum of hyperactive movements involving the muscles of the orofacial complex. They are rare conditions and are described in the literature primarily in case reports originating from neurologists, psychiatrists, and the dental community. The focus of this review is to provide a phenomenological description of different oral motor disorders including oromandibular dystonia, orofacial dyskinesia and orolingual tremor, and to offer management strategies for optimal treatment based on the current literature. A literature search of full text studies using PubMed/Medline and Cochrane library combined with a manual search of the reference lists was conducted until June 2021. Results from this search included meta-analyses, systematic reviews, reviews, clinical studies, case series, and case reports published by neurologists, psychiatrists, dentists and oral and maxillofacial surgeons. Data garnered from these sources were used to provide an overview of most commonly encountered movement disorders of the mouth, aiding physicians in recognizing these rare conditions and in initiating appropriate therapy.

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.

Botulinum Toxin Therapy for Oromandibular Dystonia and Other Movement Disorders in the Stomatognathic System

Various movement disorders, such as oromandibular dystonia, oral dyskinesia, bruxism, functional (psychogenic) movement disorder, and tremors, exist in the stomatognathic system. Most patients experiencing involuntary movements due to these disorders visit dentists or oral surgeons, who may be the first healthcare providers. However, differential diagnoses require neurological and dental knowledge. This study aimed to review scientific advances in botulinum toxin therapy for these conditions. The results indicated that botulinum toxin injection is effective and safe, with few side effects in most cases when properly administered by an experienced clinician. The diagnosis and treatment of movement disorders in the stomatognathic system require both neurological and dental or oral surgical knowledge and skills, and well-designed multicenter trials with a multidisciplinary team approach must be necessary to ensure accurate diagnosis and proper treatment.

Long-Term Deutetrabenazine Treatment for Tardive Dyskinesia Is Associated With Sustained Benefits and Safety: A 3-Year, Open-Label Extension Study

Background

Deutetrabenazine is a vesicular monoamine transporter 2 inhibitor approved for the treatment of tardive dyskinesia (TD) in adults. In two 12-week pivotal studies, deutetrabenazine demonstrated statistically significant improvements in Abnormal Involuntary Movement Scale (AIMS) scores, with favorable safety/tolerability in TD patients. This study reports long-term efficacy and safety of deutetrabenazine in a 3-year, single-arm, open-label extension (OLE) study.

Methods

Patients who completed the pivotal studies could enroll in this single-arm OLE study, titrating up to 48 mg/day based on dyskinesia control and tolerability. Efficacy was assessed based on change from baseline in total motor AIMS score, Clinical Global Impression of Change (CGIC) and Patient Global Impression of Change (PGIC), and quality of life (QOL) assessments. Safety evaluation included adverse event (AE) incidence, reported using exposure-adjusted incidence rates, and safety scales.

Results

343 patients enrolled in the study (6 patients were excluded). At Week 145 (mean dose: 39.4 ± 0.83 mg/day), mean ± SE change from baseline in total motor AIMS score was −6.6 ± 0.37 and 67% of patients achieved ≥50% improvement in total motor AIMS score. Based on CGIC and PGIC, 73% and 63% of patients achieved treatment success, respectively. QOL improvements were also observed. Deutetrabenazine was generally well tolerated, with low rates of mild-to-moderate AEs and no new safety signals; most safety scales remained unchanged over time.

Conclusions

Long-term deutetrabenazine treatment was associated with sustained improvement in AIMS scores, indicative of clinically meaningful long-term benefit, and was generally well tolerated. Results suggest deutetrabenazine may provide increasing benefit over time without increases in dose.

Long-Term Safety and Efficacy of Deutetrabenazine in Younger and Older Patients With Tardive Dyskinesia

OBJECTIVES

To assess long-term safety and efficacy of deutetrabenazine in younger (<55 years) and older (≥55 years) adult participants with tardive dyskinesia (TD).

DESIGN

Three-year, single-arm, open-label extension (OLE) study enrolling participants who completed the 12-week, pivotal ARM-TD or AIM-TD studies.

SETTING

Seventy-six centers in the United States and Europe.

PARTICIPANTS

A total of 337 participants with TD (119 younger and 218 older).

INTERVENTION

Deutetrabenazine was initiated at 12 mg/day and titrated once weekly by 6 mg/day using a response-driven dosing regimen until adequate dyskinesia control was reached or a clinically significant adverse event occurred.

MEASUREMENTS

This post hoc analysis assessed change and percent change from baseline in total motor Abnormal Involuntary Movement Scale (AIMS) score, response rates for ≥50% AIMS improvement, Clinical Global Impression of Change (CGIC), Patient Global Impression of Change (PGIC), and safety in younger and older participants with TD.

RESULTS

After 3 years of open-label treatment, mean deutetrabenazine dose was ∼39.5 mg/day in both groups. Mean±SE changes from baseline in total motor AIMS score were -6.7 ± 0.62 and -6.5 ± 0.47 in younger and older participants, respectively (percent changes: -61.4% ± 4.10% and -54.6% ± 3.01%); 76% of younger and 62% of older participants achieved ≥50% AIMS response. Most younger and older participants achieved treatment success per CGIC (67% and 76%) and PGIC (64% and 63%). Deutetrabenazine was generally well tolerated in both groups.

CONCLUSIONS

Deutetrabenazine treatment was associated with sustained improvements in total motor AIMS score, treatment success, and improved quality of life, and was well tolerated in younger and older adults with TD in this 3-year OLE study.

Atypical dyskinesias under treatment with antipsychotic drugs: Report from the AMSP multicenter drug safety project

OBJECTIVES

The aim of this study was to describe atypical dyskinesias (AtypDs) occurring during treatment with antipsychotic drugs (APDs). AtypDs are dyskinesias showing either an unusual temporal relationship between onset of treatment and start of the adverse drug reaction (ADR) or an unusual presentation of clinical symptoms.

METHODS

Data on the utilisation of APDs and reports of severe APD-induced AtypDs were collected using data from the observational pharmacovigilance programme - 'Arzneimittelsicherheit in der Psychiatrie (English: drug safety in psychiatry)' (AMSP) - from 1993 to 2016.

RESULTS

A total of 495,615 patients were monitored, of which 333,175 were treated with APDs. Sixty-seven cases (0.020%) of severe AtypDs under treatment with APDs were registered. The diagnoses of schizophrenic disorders as well as organic mental disorders were related to significantly higher rates of AtypDs. Second-generation antipsychotic drugs (SGAs) showed slightly higher rates of AtypDs (0.024%) than high-potency (0.011%) or low-potency first-generation antipsychotic drugs (FGAs; 0.006%). In 41 cases (61.2%), two or more drugs were found to cause AtypDs.

CONCLUSIONS

Our study indicates that AtypDs are rare ADRs. SGAs may have a higher risk for the occurrence of AtypDs than FGAs. Clinicians should be aware of this ADR and patients should be monitored and examined carefully.

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

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

PLAIN LANGUAGE SUMMARY

Plain Language Summary (In Japanese).

VISUAL SUMMARY

Visual Summary (In Japanese).

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.

A long-term, open-label study of valbenazine for tardive dyskinesia

BACKGROUND

Individuals with tardive dyskinesia (TD) who completed a long-term study (KINECT 3 or KINECT 4) of valbenazine (40 or 80 mg/day, once-daily for up to 48 weeks followed by 4-week washout) were enrolled in a subsequent study (NCT02736955) that was primarily designed to further evaluate the long-term safety of valbenazine.

METHODS

Participants were initiated at 40 mg/day (following prior valbenazine washout). At week 4, dosing was escalated to 80 mg/day based on tolerability and clinical assessment of TD; reduction to 40 mg/day was allowed for tolerability. The study was planned for 72 weeks or until termination due to commercial availability of valbenazine. Assessments included the Clinical Global Impression of Severity-TD (CGIS-TD), Patient Satisfaction Questionnaire (PSQ), and treatment-emergent adverse events (TEAEs).

RESULTS

At study termination, 85.7% (138/161) of participants were still active. Four participants had reached week 60, and none reached week 72. The percentage of participants with a CGIS-TD score ≤2 (normal/not ill or borderline ill) increased from study baseline (14.5% [23/159]) to week 48 (64.3% [36/56]). At baseline, 98.8% (158/160) of participants rated their prior valbenazine experience with a PSQ score ≤2 (very satisfied or somewhat satisfied). At week 48, 98.2% (55/56) remained satisfied. Before week 4 (dose escalation), 9.4% of participants had ≥1 TEAE. After week 4, the TEAE incidence was 49.0%. No TEAE occurred in ≥5% of participants during treatment (before or after week 4).

CONCLUSIONS

Valbenazine was well-tolerated and persistent improvements in TD were found in adults who received once-daily treatment for >1 year.

Assessment of the Impact of Tardive Dyskinesia in Clinical Practice: Consensus Panel Recommendations

PURPOSE

Tardive dyskinesia (TD) is a hyperkinetic movement disorder in which patients experience abnormal involuntary movements that can have profound negative impacts on physical, cognitive, and psychosocial functioning. Use of measures to assess the functional impact of TD in routine clinical practice is lacking. To address this gap, an advisory panel of experts in psychiatry and movement disorder neurology was convened to develop consensus recommendations on assessment of the impact of TD on patients' functioning that can be used in clinical practice.

METHODS

An advisory panel provided recommendations using an iterative process, beginning with a narrative literature review regarding current practices for assessing the impact of TD in clinical settings. A detailed summary was generated, and the advisory panel provided comments about the content and answered questions about assessing TD impact in clinical practice. The panelists' responses were discussed during a virtual meeting held on August 28, 2020. A second meeting on September 25, 2020, focused on developing and refining recommendations for assessment of the impact of TD in clinical practice. At the conclusion of the second meeting, general consensus was reached on all recommendation statements.

RESULTS

As part of routine clinical practice, it is imperative to assess the impact of TD on the patient's life to help guide treatment decisions. Key domains for assessing the overall impact of TD include social, physical, vocational, and psychological functioning and the impact of TD on the underlying psychiatric disorder. Assessment of TD impact should be performed at every patient visit. Impact assessments should include consultation with patients, caregivers, and family members. Shared decision-making to initiate TD treatment should consider impact.

CONCLUSION

The impact of TD should be assessed routinely, including the key domains of social, physical, vocational, and psychological functioning and the impact of TD on the underlying psychiatric disorder.

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.

Tardive Dyskinesia in Older Persons Taking Antipsychotics

Tardive dyskinesia (TD) is a hyperkinetic movement disorder caused by the use of dopamine receptor-blocking agents (DRBAs), a category of medications that includes first- and second-generation antipsychotics (APs) and agents such as metoclopramide that are used for the treatment of nausea and gastrointestinal dysmotility. While TD can affect people of all ages, older age is associated with increased risk of TD and also with the emergence of TD occurring after shorter treatment durations and lower dosages of DRBAs. TD is characterized by involuntary movements that include the face, limbs, and trunk, and is associated with increased comorbidities, social stigmatization, and impaired physical and mental health. Once present, TD tends to persist despite AP dose adjustment or discontinuation. Even with the use of US Food and Drug Administration (FDA)-approved medications for TD, symptoms may persist. Because the leading hypothesis for the pathophysiology of TD has been dysregulation of dopamine transmission due to treatment with DRBAs, APs that avoid postsynaptic dopamine receptor blockade may provide an alternative therapeutic approach for patients who require an AP. In this review, we discuss the risks, burdens, prevention, and management of TD, with a focus on older people.

Psychotropic medications induced parkinsonism and akathisia in people attending follow-up treatment at Jimma Medical Center, Psychiatry Clinic

OBJECTIVE

To determine the magnitude and factors associated with psychotropic drug-induced parkinsonism and akathisia among mentally ill patients.

METHODS

A hospital-based cross-sectional study was conducted with a total of 410 participants attending a follow-up treatment service at Jimma Medical Center, a psychiatry clinic from April to June 2019. Participants were recruited using a systematic random sampling method. Drug-induced parkinsonism and akathisia were assessed using the Extra-pyramidal Symptom Rating Scale. Substance use was assessed using the World Health Organization Alcohol, Smoking, and Substance Involvement Screening Test. Data entry was done using EpiData version 3.1, and analysis done by the Statistical Package for Social Sciences version 22. Statistically, the significant association was declared by adjusted odds ratio, 95% confidence interval, and p-value less than or equal to 0.05.

RESULTS

The mean age of the respondents was 33.3 years (SD ± 8.55). Most of the participants 223 (54.4%) had a diagnosis of schizophrenia. The prevalence of drug-induced parkinsonism was 14.4% (95% CI: 11.0 to 18.0) and it was 12.4% (95% CI: 9.3 to 15.4) for drug-induced akathisia. The result of the final model found out drug-induced parkinsonism was significantly associated with female sex, age, type of antipsychotics, physical illness, and anti-cholinergic medication use. Similarly, female sex, chlorpromazine equivalent doses of 200 to 600 mg, combined treatment of sodium valproate with antipsychotic, and severe khat/Catha edulis use risk level was significantly associated with akathisia.

CONCLUSION

One of seven patients developed drug-induced parkinsonism and akathisia. Careful patient assessment for drug-induced movement disorders, selection of drugs with minimal side effects, screening patients for physical illness, and psycho-education on substance use should be given top priority.

Oromandibular dystonia: a diagnosis not to miss

Oromandibular dystonia (OMD) is characterised by sustained or repetitive involuntary movements of the jaw, face, and tongue. People with the condition may present to their dentist, general practitioner, or a secondary care specialist with non-specific symptoms including jaw or facial pain, bruxism, subluxations or dislocations of the jaw; fractured teeth or dental restorations, or both; or jaw tremor. Many clinicians are not aware of the disorder and this can lead to delayed diagnoses, unnecessary complications, and inappropriate treatment. OMD is an important diagnosis not to miss because referral for specialist management can provide good long-term results. To aid early, accurate diagnosis, this paper focuses on the key clinical features of the disorder and its dental and medical mimics.

The effects of valbenazine on tardive dyskinesia in older and younger patients

OBJECTIVE

To evaluate the effects of once-daily valbenazine (40 or 80 mg/d) in older and younger adults with tardive dyskinesia (TD).

METHODS

Data were pooled from three 6-week, randomized, double-blind, placebo-controlled (DBPC) studies (KINECT [NCT01688037], KINECT 2 [NCT01733121], and KINECT 3 [NCT02274558]) and two long-term studies (KINECT 3 extension and KINECT 4 [NCT02405091]). Outcomes analyzed in older and younger participants (55 years or older and younger than 55 years, respectively) included Abnormal Involuntary Movement Scale (AIMS) response (threshold of greater than or equal to 50% improvement from baseline in total score [items 1 to 7]) and Clinical Global Impression of Change-Tardive Dyskinesia (CGI-TD) response (score 2 or less ["very much improved" or "much improved"]). Safety assessments included treatment-emergent adverse events (TEAEs).

RESULTS

At week 6 (end of DBPC treatment), the percentage of participants who met the AIMS response threshold was higher with valbenazine versus placebo in both subgroups: 55 years or older (80 mg/d, 39.7% [P < .001]; 40 mg/d, 28.6% [P < .01]; placebo, 9.7%); younger than 55 years (80 mg/d, 39.5% [P < .001]; 40 mg/d, 20.0% [P > .05]; placebo, 10.8%). The percentage of participants with CGI-TD response was also higher with valbenazine versus placebo: 55 years or older (80 mg/d, 41.3% [P < .01]; 40 mg/d, 30.2% [P > .05]; placebo, 19.4%); younger than 55 years (80 mg/d, 39.5% [P < .05]; 40 mg/d, 35.3% [P < .05]; placebo, 18.5%). Responses at week 48 (end of long-term treatment, combined doses) were as follows: 55 years or older (AIMS, 70.7%; CGI-TD, 82.8%); younger than 55 years (AIMS, 58.7%; CGI-TD, 72.3%). No significant differences between older and younger subgroups were found for AIMS or CGI-TD response. No new safety signals or TEAEs of clinical concern were found in older participants who received long-term treatment.

CONCLUSIONS

Valbenazine improved TD and was generally well tolerated in older and younger adults.

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

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

Metoclopramide as a prokinetic agent for diabetic gastroparesis: revisiting the risk of Parkinsonism

Background:

Metoclopramide is used to relieve gastrointestinal symptoms, however, it could cause adverse reactions of motor disorders. The aim of this study was to investigate whether metoclopramide treatment has a duration–response or dose–response effect and to estimate the risk of developing Parkinsonism following different and specific durations of treatment.

Methods:

A cohort study of newly diagnosed type 2 diabetes mellitus in 45- to 79-year-old patients, between 1999 and 2008, was selected using the Longitudinal Health Insurance Database 2005. A nested case–control study was conducted in the diabetes cohort in which all incident cases of Parkinsonism were identified. We randomly matched each case with up to 10 controls from the risk set. Conditional logistic regression was utilized to estimate odds ratio of Parkinsonism associated with metoclopramide use.

Results:

A total of 34,685 patients with diabetes were assembled as the cohort, and 541 incident Parkinsonism cases were identified. There were duration–response and dose–response effects on the risk of developing Parkinsonism. Compared with never-use patients, the adjusted odds ratios (ORs) of continuing therapy for 0–1 month, 1–2 months, 2–3 months, 3–5 months, and more than 5 months were 1.17 [95% confidence interval (CI) 0.93–1.45], 1.44 (95% CI 1.04–2.00), 1.74 (95% CI 1.14–2.65), 1.90 (95% CI 1.23–2.93), and 2.17 (95% CI 1.50–3.12), respectively.

Conclusions:

With metoclopramide treatment, regardless of less or more than 3 months of use, the risk of developing Parkinsonism in patients with newly diagnosed diabetes escalated with the duration of therapy. Therefore, we recommend close monitoring for the development of Parkinsonism in patients treated with metoclopramide, particularly (but not limited to) those with prolonged exposure.

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.

Prevalence and management practice of first generation antipsychotics induced side effects among schizophrenic patients at Amanuel Mental Specialized Hospital, central Ethiopia: cross-sectional study

BACKGROUND

First-generation antipsychotics (FGAs) are associated with a range of adverse events which can significantly reduce patients' quality of life and contribute to non-adherence. The aim of this study was to assess the prevalence and management practice of first generation antipsychotics induced side effects among schizophrenic patients.

METHODS

The study was conducted at Amanuel Mental Specialized Hospital from March to June, 2017. Data from patients were collected using a pretested structured questionnaire. Demographics and side effects of antipsychotics were collected by face to face interview. Clinical characteristics, medications and previous history of adverse drug events were extracted from medical records using data abstraction format. The data were analyzed using statistical software for social sciences (SPSS) version 20. Descriptive statistics and chi-square tests were done. Statistical significance was considered at p < 0.05.

RESULTS

Out of 356 participants, 300 of them had complete data and were included in the study. The mean age of participants was 33.71 ± 10.2 years. The majority, 195(65.0%), of participants were males. Most of the participants, 293(97.7%), developed FGA medication induced side effects. One hundred sixty three (54.3%) participants were treated with Trihexyphenidyl for FGAs induced side effects. Dose reduction of antipsychotics was done for 51(17.0%) participants. Most of the participants' side effects were not managed according to American Psychiatric Association guideline; 178 (82.4%). The most common types of FGAs induced side effects were cardiovascular side effects 169(56.3%); sedation and CNS side effects 149(49.6%); and extrapyramidal side effects 114(38.0%). There is a significant association between occurrence of side effects of FGAs and duration of illness (P = 0.04).

CONCLUSIONS

The prevalence of first generation antipsychotics induced side effects was high. However, management practice of the side effects was minimal.

Tardive dyskinesia update: the syndrome

Tardive dyskinesia is a common iatrogenic neurological and neurobehavioural syndrome associated with the use of antidopaminergic medication, especially antipsychotics. Prior to the introduction of the newer antipsychotics in the 1990s, it was one of the major areas of psychiatric research but interest waned as the new drugs were reputed to have a reduced liability to extrapyramidal adverse effects in general, a claim now discredited by numerous pragmatic research studies. Early small-scale short-term prevalence studies were presented as evidence to support the assumption that patients on the newer drugs did indeed have a lower prevalence of tardive dyskinesia but recent large-scale review of studies with patients exposed for longer suggest that things have not changed. This article presents a clinical overview of a complex and varied syndrome in terms of its phenomenology, epidemiology and risk factors; a companion article will consider treatment. This overview aims to highlight tardive dyskinesia once again, especially to practitioners who have trained in an environment where this was considered mainly in historical terms.

LEARNING OBJECTIVES

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DECLARATION OF INTEREST

None.

Treatment of tardive dyskinesia with VMAT-2 inhibitors: a systematic review and meta-analysis of randomized controlled trials

Aim

The aim of this study was to summarize the characteristics, efficacy, and safety of vesicular monoamine transporter-2 (VMAT-2) inhibitors for treating tardive dyskinesia (TD).

Materials and methods

We conducted a literature search in PubMed, Cochrane Database, and ClinicalTrials.gov, screening for systematic reviews, meta-analyses or double-blind, randomized, placebo-controlled trials (DBRPCTs) reporting efficacy or safety data of VMAT-2 inhibitors (tetrabenazine, deutetrabenazine, and valbenazine) in patients with TD. A random effects meta-analysis of efficacy and safety data from DBRPCTs was performed.

Results

Two acute, 12-week DBRPCTs with deutetrabenazine 12–48 mg/day (n=413) and 4 acute, 4–6-week double-blind trials with valbenazine 12.5–100 mg/day (n=488) were meta-analyzable, without meta-analyzable, high-quality data for tetrabenazine. Regarding reduction in total Abnormal Involuntary Movement Scale (AIMS) scores (primary outcome), both deutetrabenazine (k=2, n=413, standardized mean difference [SMD] =−0.40, 95% confidence interval [CI] =−0.19, −0.62, p<0.001; weighted mean difference (WMD) =−1.44, 95% CI =−0.67, −2.19, p<0.001) and valbenazine (k=4, n=421, SMD =−0.58, 95% CI =−0.26, −0.91, p<0.001; WMD =−2.07, 95% CI =−1.08, −3.05, p<0.001) significantly outperformed placebo. Results were confirmed regarding responder rates (≥50% AIMS total score reduction; deutetrabenazine: risk ratio [RR] =2.13, 95% CI =1.10, 4.12, p=0.024, number-needed-to-treat [NNT] =7, 95% CI =3, 333, p=0.046; valbenazine: RR =3.05, 95% CI =1.81, 5.11, p<0.001, NNT =4, 95% CI =3, 6, p<0.001). Less consistent results emerged from patient-rated global impression-based response (p=0.15) and clinical global impression for deutetrabenazine (p=0.088), and for clinical global impression change for valbenazine (p=0.67). In an open-label extension (OLE) study of deutetrabenazine (≤54 weeks) and a dose-blinded valbenazine study (≤48 weeks), responder rates increased over time. With valbenazine, discontinuation effects were studied, showing TD symptom recurrence towards baseline severity levels within 4 weeks after valbenazine withdrawal. No increased cumulative or specific adverse (AEs) events versus placebo (acute trials) in extension versus acute trial data were observed.

Conclusion

The 2 VMAT-2 inhibitors, valbenazine and deutetrabenazine, are effective in treating TD, both acutely and long-term, without concerns about increased risk of depression or suicide in the TD population. No head-to-head comparison among VMAT-2 inhibitors and no high-quality, meta-analyzable data are available for tetrabenazine in patients with TD.

Clinical risk factors for the development of tardive dyskinesia

BACKGROUND

Tardive dyskinesia (TD) is a severe condition that can affect almost 1 out of 4 patients on current or previous antipsychotic treatment, including both first-generation antipsychotics (FGAs) and second-generation antipsychotics (SGAs). While two novel vesicular monoamine transporter inhibitors, deutetrabenazine and valbenazine, have shown acute efficacy for TD, the majority of patients do not remit, and TD appears to recur once treatment is withdrawn. Hence, prevention of TD remains a crucial goal.

METHODS

We provide a clinically oriented overview of risk factors for TD, dividing them into patient-, illness- and treatment-related variables, as well as nonmodifiable and modifiable factors.

RESULTS

Unmodifiable patient-related and illness-related risk factors for TD include older age, female sex, white and African descent, longer illness duration, intellectual disability and brain damage, negative symptoms in schizophrenia, mood disorders, cognitive symptoms in mood disorders, and gene polymorphisms involving antipsychotic metabolism and dopamine functioning. Modifiable comorbidity-related and treatment-related factors include diabetes, smoking, and alcohol and substance abuse, FGA vs SGA treatment, higher cumulative and current antipsychotic dose or antipsychotic plasma levels, early parkinsonian side effects, anticholinergic co-treatment, akathisia, and emergent dyskinesia.

DISCUSSION

Clinicians using dopamine antagonists need to consider risk factors for TD to minimize TD and its consequences.

Rational pharmacotherapy in early psychosis

Background

An increased focus in research specific to first-episode schizophrenia has provided a rapidly growing body of evidence that can be directly translated to clinical practice.

Aims

To provide clinical recommendations specific to effective pharmacotherapy of first-episode schizophrenia.

Method

Evidence from clinical trials focused on the first-episode population is combined with data from other areas of investigation.

Results

In first-episode psychosis, when to initiate treatment is not always clear, being intimately linked to challenges regarding early detection and diagnosis. There may be differences in antipsychotic dosing, patterns of response and sensitivity to side-effects. Adherence appears to be even more problematic at this stage.

Conclusions

Clinicians currently treating early psychosis have considerably more information to guide their decision-making. However, the speed at which the field is growing is a reminder totreatthis knowledge as a work in progress.

Severe Tardive Dystonia on Low Dose Short Duration Exposure to Atypical Antipsychotics: Factors Explored

Tardive dystonia (TD) is a serious side effect of antipsychotic medications, more with typical antipsychotics, that is potentially irreversible in affected patients. Studies show that newer atypical antipsychotics have a lower risk of TD. As a result, many clinicians may have developed a false sense of security when prescribing these medications. We report a case of 20-year-old male with hyperthymic temperament and borderline intellectual functioning, who developed severe TD after low dose short duration exposure to atypical antipsychotic risperidone and then olanzapine. The goal of this paper is to alert the reader to be judicious and cautious before using casual low dose second generation antipsychotics in patient with no core psychotic features, hyperthymic temperament, or borderline intellectual functioning suggestive of organic brain damage, who are more prone to develop adverse effects such as TD and monitor the onset of TD in patients taking atypical antipsychotics.

Clozapine Treatment of Olanzapine-induced Tardive Dyskinesia: A Case Report

Tardive dyskinesias (TD) are serious, often irreversible side effects of dopamine blocking agents, most commonly first-generation antipsychotics. No definitive treatment exists, with different interventions showing inconsistent results. We report a case of TD presenting after 12 years of olanzapine therapy in a 66-year-old Hispanic male with paranoid schizophrenia. The TD symptoms were successfully treated within a few weeks by switching to clozapine. Two cases of olanzapine-induced TD treated with clozapine have previously been reported, but in those cases, the symptom onset was quicker, ranging from a few months to a few years after initiation of olanzapine therapy, and the treatment response was relatively slower. Clinicians should carefully monitor for symptoms of TD after prolonged treatment with olanzapine and other antipsychotics. If otherwise indicated for psychiatric treatment, clozapine can be considered a good choice for patients with TD in preventing or reversing the debilitating consequences of this condition.

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.

Drug-Induced Movement Disorders

Drug-induced movement disorders (DIMDs) pose a significant burden to patients, often resulting in nonadherence, disease relapse, and decreased quality of life. Dopamine-receptor blocking agents such as conventional antipsychotics (eg, haloperidol and chlorpromazine) and antiemetics (eg, metoclopramide and prochlorperazine) are most commonly implicated. DIMDs can be categorized by the onset of symptoms: acute reactions occurring hours to days after exposure, subacute DIMDs appearing within weeks, and tardive occurring months to years after drug exposure. The DIMDs of akathisia, tardive dyskinesia, dystonia, and parkinsonism are reviewed. Their epidemiology, mechanism, clinical presentation and differential diagnosis, risk factors, morbidity and mortality, and prevention and management are discussed. For many of these disorders, treatment inconsistently provides benefit, and therefore, primary prevention is essential. Clinicians and other healthcare professionals play a key role in the identification of patients with DIMDs, or those at risk, and in implementing prevention and treatment plans.

[Prevention and treatment of tardive dyskinesia caused by antipsychotic drugs]

INTRODUCTION

Tardive dyskinesia (TD) is a movement disorder of tongue, jawbone, trunk and/or limbs that may appear after a prolonged use of dopamine receptor blocking agents (after 3 months of treatment or after 1 month for patients over 60), and that are present during at least four consecutive weeks. TD is a frequent side effect of both classical neuroleptics and new generation antipsychotic drugs. The prevalence of iatrogenic TD is between 24 and 32 % after treatment with classical neuroleptics and about 13 % after treatment with a new generation antipsychotic.

OBJECTIVE

This paper presents an updated literature review of data on diagnosis, prevention and treatment of TD.

METHODS

We conducted a review of literature using the Medline Browser tool, screening studies from 1950 to 2013 in English or French with keywords « tardive dyskinesia », « tardive dystonia », and « abnormal movements caused by antipsychotic drugs ».

RESULTS

We first describe and define semeiological features of TD: dystonia, tremor, myoclonus, acathisie, chorea, ballism and athetosia. Secondarily, we resume the main differential diagnoses to exclude when confronted with this kind of movement disorders. Differential diagnoses for dyskinesia can be classified between primary (Parkinson and Huntington diseases) and secondary (Wilson disease, intoxication, metabolic abnormality, cerebrovascular accident) abnormal movements. Psychogenic TD can be evocated if previous pathologies are excluded in case of atypical clinical presentation. We detail the risk factors for TD. Endogenous risk factors are related to the patient's age, underlying psychiatric disease (bipolar disorder or Alzheimer dementia), addiction to alcohol or cocaine, female gender, or neurodevelopmental vulnerability. Iatrogenic risk factors are high doses of antipsychotics, long or intermittent administration, and particular pharmaceutical classes or associations of antipsychotics. As a comprehensive tool, we review the main physiopathological hypotheses to explain the occurrence of TD in some patients: hypersensitivity of D2 neuronal receptor or neurotoxicity associated with oxidative stress mechanisms. We also summarize the current guidelines for prevention and treatment of TD. Three successive curative strategies are suggested in the literature. First, the clinician can adapt the current antipsychotic treatment (switch to a new generation antipsychotic, diminution or cessation of antipsychotic drugs). If this first intervention is not pertinent or ineffective, the clinician can prescribe an antikinetic therapeutic agent, such as tetrabenazine, or an antioxidant. Review of the published studies does not show proof of efficacy of cholinergic or anticholinergic drugs, benzodiazepine or other GABAergic drugs, nor for amantadine. Non-medication therapeutics such as ECT and TMS are discussed, but the level of proof is insufficient to promote them as a curative treatment for TD. In case of high resistance and discomfort for the patient, a neurosurgical intervention should be discussed. These curative interventions are limited, emphasising the importance of TD prevention, by limiting the prescription and doses of antipsychotics, regularly evaluating their side effects and informing the patient of TD's risk.

CONCLUSION

We propose to practitioners a synthesised update of literature concerning a frequent iatrogenic effect of antipsychotics. Nevertheless, no solid guidelines have as yet been established, and further clinical studies are expected in order to better understand this frequent and discomforting side effect.

Drug-induced movement disorders

INTRODUCTION

Drug-induced movement disorders (DIMDs) can be elicited by several kinds of pharmaceutical agents. The major groups of offending drugs include antidepressants, antipsychotics, antiepileptics, antimicrobials, antiarrhythmics, mood stabilisers and gastrointestinal drugs among others.

AREAS COVERED

This paper reviews literature covering each movement disorder induced by commercially available pharmaceuticals. Considering the magnitude of the topic, only the most prominent examples of offending agents were reported in each paragraph paying a special attention to the brief description of the pathomechanism and therapeutic options if available.

EXPERT OPINION

As the treatment of some DIMDs is quite challenging, a preventive approach is preferable. Accordingly, the use of the offending agents should be strictly limited to appropriate indications and they should be applied in as low doses and as short duration as the patient's condition allows. As most of DIMDs are related to an unspecific adverse action of medications in the basal ganglia and the cerebellum, future research should focus on better characterisation of the neurochemical profile of the affected functional systems, in addition to the development of drugs with higher selectivity and better side-effect profile.

Tardive dyskinesia (syndrome): Current concept and modern approaches to its management

Tardive dyskinesia is a serious, disabling and potentially permanent, neurological hyperkinetic movement disorder that occurs after months or years of taking psychotropic drugs. The pathophysiology of tardive dyskinesia is complex, multifactorial and still not fully understood. A number of drugs were tried for the management of this motor disturbance, yet until now no effective and standard treatment has been found. It is very disappointing to realize that the introduction of antipsychotics from the second generation has not significantly decreased the prevalence and incidence of tardive dyskinesia. Therefore, the management of this motor disturbance remains an actual topic as well as a challenge for clinicians. This review summarizes recent relevant publications concerning the treatment of tardive dyskinesia.

Incidence of tardive dyskinesia in older adult patients treated with olanzapine or conventional antipsychotics

BACKGROUND

The risk of persistent tardive dyskinesia (TD) was compared in patients with acute psychosis or agitation aged 55 years or older who were treated with olanzapine (OLZ) or conventional antipsychotic (CNV) drug therapy.

METHODS

Patients without TD were randomized to treatment with OLZ (2.5-20 mg/d; n = 150) or CNV (dosed per label; n = 143). Following a 6-week drug tapering/initiation period, patients without TD were treated with OLZ or CNV for up to 1 year. The a priori defined primary outcome end point was persistent TD defined as Abnormal Involuntary Movement Scale (AIMS) scores = 2 on at least 2 items or ≥3 on at least 1 item (items 1-7) lasting at least for 1 month (Criterion A). Post hoc analyses assessed persistent TD meeting the criterion of moderate severity defined as AIMS score ≥3 on at least 1 item persisting for 1 month (Criterion B) and probable TD defined as elevated AIMS scores (Criterion A or B) not persisting for 1 month. Treatment groups were compared using Kaplan-Meier curve with log-rank exact test.

RESULTS

On average, patients were 78 years of age; the predominant diagnosis was dementia (76.7% in the OLZ group and 82.5% in the CNV group). Approximately, 40.6% of patients in the CNV group received haloperidol. No significant difference in time to developing persistent TD was observed during treatment with OLZ or CNV (cumulative incidence: OLZ, 2.5% [95% confidence interval [95% CI]: 0.5-7.0]; CNV, 5.5% [95% CI: 2.1-11.6], P = .193). The exposure-adjusted event rates per 100 person-years were not significantly different between treatment groups: OLZ (2.7) and CNV (6.3; ratio: 0.420; 95% CI: 0.068-1.969). Post hoc analyses revealed a significantly lower risk of at least moderately severe persistent TD persisting for 1 month (P = .012) and probable TD not persisting for 1 month (Criterion A, P = .030; Criterion B, P = .048) in OLZ-treated patients. For those patients without significant extrapyramidal symptoms at baseline, significantly more patients in the CNV treatment group developed treatment-emergent parkinsonism than for patients in the OLZ treatment group (CNV: 70%, 35 of 50 patients; OLZ 44%, 25 of 57 patients; P = .011). No significant difference between the groups was observed for treatment-emergent akathisia (CNV: 6%, 7 of 117 patients; OLZ: 10%, 13 of 130 patients; P = .351).

CONCLUSION

The cumulative incidence of persistent TD was low and the risk of persistent TD did not differ significantly among predominantly older adult patients having dementia with acute psychosis or agitation treated with OLZ or CNV.

Pharmacogenetics of antipsychotic-induced movement disorders as a resource for better understanding Parkinson's disease modifier genes

Antipsychotic-induced movement disorders are major side effects of antipsychotic drugs among schizophrenia patients, and include antipsychotic-induced parkinsonism (AIP) and tardive dyskinesia (TD). Substantial pharmacogenetic work has been done in this field, and several susceptibility variants have been suggested. In this paper, the genetics of antipsychotic-induced movement disorders is considered in a broader context. We hypothesize that genetic variants that are risk factors for AIP and TD may provide insights into the pathophysiology of motor symptoms in Parkinson’s disease (PD). Since loss of dopaminergic stimulation (albeit pharmacological in AIP and degenerative in PD) is shared by the two clinical entities, genes associated with susceptibility to AIP may be modifier genes that influence clinical expression of PD motor sub-phenotypes, such as age at onset, disease severity, or rate of progression. This is due to their possible functional influence on compensatory mechanisms for striatal dopamine loss. Better compensatory potential might be beneficial at the early and later stages of the PD course. AIP vulnerability variants could also be related to latent impairment in the nigrostriatal pathway, affecting its functionality, and leading to subclinical dopaminergic deficits in the striatum. Susceptibility of PD patients to early development of l-DOPA induced dyskinesia (LID) is an additional relevant sub-phenotype. LID might share a common genetic background with TD, with which it shares clinical features. Genetic risk variants may predispose to both phenotypes, exerting a pleiotropic effect. According to this hypothesis, elucidating the genetics of antipsychotic-induced movement disorders may advance our understanding of multiple aspects of PD and it clinical course, rendering this a potentially rewarding field of study.

Association of tardive dyskinesia with variation in CYP2D6: Is there a role for active metabolites?

BACKGROUND

The aim of this study was to examine whether there was an association between tardive dyskinesia (TD) and number of functional CYP2D6 genes.

METHODS

A Caucasian sample of 70 patients was recruited in 1996-1997 from South London and Maudsley National Health Service (NHS) Foundation Trust, UK. Subjects had a DSM-IIIR diagnosis of schizophrenia and were treated with typical antipsychotics at doses equivalent to at least 100 mg chlorpromazine daily for at least 12 months prior to assessment. All patients were genotyped for CYP2D6 alleles*3-5, *41, and for amplifications of the gene.

RESULTS

There were 13 patients with TD. The mean (standard deviation (SD)) years of duration of antipsychotic treatment in TD-positive was 15.8 (7.9) vs TD-negative 11.1 (7.4) (p=0.04). Increased odds of experiencing TD were associated with increased ability to metabolize CYP2D6, as measured by genotypic category (odds ratio (OR)=4.2), increasing duration in treatment (OR=1.0), and having drug-induced Parkinsonism (OR=9.7).

DISCUSSION

We found a significant association between CYP2D6 genotypic category and TD with the direction of effect being an increase in the number of functional CYP2D6 genes being associated with an increased risk of TD. This is the first study to examine the association between TD and CYP2D6 in Caucasians with this number of genotypic categories. In the future, metabolomics may be utilized in the discovery of biomarkers and novel drug targets.

The effects of electroconvulsive therapy on tardive dystonia or dyskinesia induced by psychotropic medication: a retrospective study

BACKGROUND

Tardive dystonia and dyskinesia are potentially irreversible neurological syndromes. Successful electroconvulsive treatment (ECT) has been reported by multiple sources; however, the existing retrospective reviews and open prospective trials provide little information on the response rate.

METHODS

Eighteen consecutive patients with tardive dystonia or dyskinesia received a standard course of ECT to treat abnormal movement. The severity of the tardive dystonia and dyskinesia was evaluated using the Abnormal Involuntary Movement Scale (AIMS) before and after the course of ECT. The patients who displayed a greater than 50% improvement in the AIMS score were classified as the responders.

RESULTS

The mean AIMS score decreased from 19.1±4.7 to 9.6±4.2. There were seven responders among the 18 patients, which yielded a 39% response rate.

CONCLUSION

ECT has a moderate but significant effect on tardive dystonia and dyskinesia.

Tardive dyskinesia: therapeutic options for an increasingly common disorder

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

The incidence of tardive dyskinesia in the study of pharmacotherapy for psychotic depression

Tardive dyskinesia (TD) is a debilitating adverse effect associated with antipsychotic treatment. Older age and the presence of mood disorder have been identified as risk factors for the development of TD. Thus, we assessed the incidence of TD in younger and older patients with major depressive disorder with psychotic features who participated in a 12-week clinical trial comparing olanzapine plus sertraline versus olanzapine plus placebo. All subjects (n = 259) were assessed with the Abnormal Involuntary Movement Scale at baseline and after 4, 8, and 12 weeks of treatment (or at termination). We used 7 different published criteria to estimate the prevalence of TD at baseline and the incidence over the duration of the trial. We compared the incidence of TD in subjects 60 years or older and those younger than 60 years. The overall prevalence and incidence of TD varied almost 10-fold, depending on the criteria (prevalence range, 1.2%-8.9%; incidence range, 0.0%-5.9%). Tardive dyskinesia was observed as a clinical adverse event in only 1 subject (0.4%). Whereas older subjects had a higher prevalence of TD at baseline, the incidence in younger and older subjects did not differ significantly. The incidence of TD was relatively low in both younger and older patients with major depressive disorder with psychotic features treated acutely with olanzapine. However, the estimate of the risk of TD varies widely, depending on the criteria used to define TD.

Tardive dyskinesia after short-term treatment with oral metoclopramide in an adolescent

CASE

The objective of this case report is to report the development of tardive dyskinesia in an African-American adolescent male after short-term treatment with metoclopramide 10 mg orally three times daily secondary to delayed gastric emptying. The patient developed symptoms of tardive dyskinesia after 2 days of therapy with metoclopramide. Metoclopramide was discontinued and diphenhydramine 50 mg was initially administered intravenously followed with 25 mg orally every 4 hours as needed. While there are case reports of drug-induced tardive dyskinesia after intravenous administration of metoclopramide, this is to our knowledge the first report of tardive dyskinesia after short-term treatment with oral metoclopramide in an adolescent.

CONCLUSION

Awareness of the risk of development of this adverse effect even with short-term treatment with metoclopramide and in younger patients is important.

Alpha-phenyl-N-tert-butylnitrone prevents oxidative stress in a haloperidol-induced animal model of tardive dyskinesia: investigating the behavioural and biochemical changes

Haloperidol (HP) is a widely prescribed antipsychotic drug used for the treatment of mental disorders. However, while providing therapeutic benefits, this drug also causes serious extrapyramidal side effects, such as tardive dyskinesia (TD). Upon chronic administration, HP causes behavioural supersensitivity to dopamine D2 receptor agonists, as well as the development of vacuous chewing movements (VCMs), in an animal model of human TD. Currently, a prevailing hypothesis to account for these behavioural abnormalities implicates oxidative stress. This study was undertaken to examine whether the free radical trapping agent, α-phenyl-N-tert-butylnitrone (PBN), can prevent the development of behavioural supersensitivity to dopamine D2 receptor agonists and the development of VCMs. Additionally, the study examined whether increased synthesis of apoptosis inducing factor (AIF) can result from HP-induced oxidative stress. Male Sprague-Dawley rats were treated with HP in conjunction with PBN, or its vehicle, for 4weeks. After a 24-hour washout period, behavioural observations were recorded along with the estimation of lipid peroxidation and antioxidant enzyme activities. The free radical trapping agent, PBN, prevented the development of behavioural supersensitivity, reduced lipid peroxidation and prevented the reduction of antioxidant enzyme activities. AIF concentrations at the mRNA and protein levels remained unchanged; therefore increased AIF gene expression is unlikely to be involved in HP-induced oxidative stress. The findings of the present study suggest the involvement of striatal free radicals in the development of behavioural supersensitivity, and free radical trapping agents, such as PBN, as possible options for the treatment of extrapyramidal side effects in humans.

Incidence of tardive dyskinesia with risperidone or olanzapine in the elderly: results from a 2-year, prospective study in antipsychotic-naïve patients

Tardive dyskinesia (TD) rates with second-generation antipsychotics (SGAs) are considered to be low relative to first-generation antipsychotics (FGAs), even in the particularly vulnerable elderly population. However, risk estimates are unavailable for patients naïve to FGAs. Therefore, we aimed to determine the TD incidence in particularly vulnerable, antipsychotic-naïve elderly patients treated with the SGA risperidone or olanzapine. The present work describes a prospective inception cohort study of antipsychotic-naïve elderly patients aged 55 years identified at New York Metropolitan area in-patient and out-patient geriatric psychiatry facilities and nursing homes at the time of risperidone or olanzapine initiation. At baseline, 4 weeks, and at quarterly periods, patients underwent assessments of medical and medication history, abnormal involuntary movements, and extra-pyramidal signs. TD was classified using Schooler-Kane criteria. Included in the analyses were 207 subjects (age: 79.8 years, 70.0% female, 86.5% White), predominantly diagnosed with dementia (58.9%) or a major mood disorder (30.9%), although the principal treatment target was psychosis (78.7%), with (59.4%) or without (19.3%) agitation. With risperidone (n=159) the cumulative TD rate was 5.3% (95% confidence interval (CI): 0.7, 9.9%) after 1 year (mean dose: 1.0±0.76 mg/day) and 7.2% (CI: 1.4, 12.9%) after 2 years. With olanzapine (n=48) the cumulative TD rate was 6.7% (CI: 0, 15.6%) after 1 year (mean dose: 4.3±1.9 mg/day) and 11.1% (CI: 0, 23.1%) after 2 years. TD risk was higher in females, African Americans, and patients without past antidepressant treatment or with FGA co-treatment. The TD rates for geriatric patients treated with risperidone and olanzapine were comparable and substantially lower than previously reported for similar patients in direct observation studies using FGAs. This information is relevant for all patients receiving antipsychotics, not just the especially sensitive elderly.

Ethical and Policy Considerations in the Application of Pharmacogenomic Testing for Tardive Dyskinesia: Case Study of the Dopamine D3 Receptor

Tardive dyskinesia (TD) is a serious adverse effect often associated with the first generation antipsychotic medications used in the management of mental health disorders such as schizophrenia. Pharmacogenomics is the study of human genomic variation in relation to individual and population variability in medication response and side effects. Neuropsychiatry is one of the clinical domains in which pharmacogenomic approaches have been extensively studied. In the late 1990s, the Glycine9 (Gly9) allele of the Serine-9-Glycine (Ser9Gly) polymorphism in dopamine D3 receptor gene (DRD3) was found to be associated with both a liability to, and worsened severity of, TD in schizophrenic patients treated with typical antipsychotics. This initial discovery has been subsequently replicated and testing for the Ser9Gly polymorphism has now become commercially available. The question that currently presents itself is whether its use should be encouraged for patients who may be prescribed a typical or atypical antipsychotic medication. However, the translation of this new technology to clinical practice presents multiple social, ethical and policy challenges. Though pharmacogenomic testing holds much promise in this scenario, many important questions remain to be answered before its widespread use can be medically and ethically justified. This article highlights the key advances in our understanding of the role of human genetic variation in the D3 receptor in relation to TD. Then, issues of uncertainty, consent, confidentiality, and access are considered with respect to the use of DRD3 polymorphism testing in risk stratification for susceptibility to tardive dyskinesia. We propose three recommendations that may help bring this technology into the clinic: 1) prospective pharmacogenomic studies of DRD3 polymorphism and TD risk should be conducted; 2) the design of such studies should be influenced by scientists, ethicists and policy makers to protect potentially vulnerable patients; and 3) appropriate knowledge transfer to front-line health care workers must take place.