Genetic association study detected misalignment in previous whole exome sequence: association study of ZNF806 and SART3 in tardive dystonia.

Tardive dystonia is one of the most serious types of extrapyramidal symptoms that antipsychotics can cause. There is no established treatment to relieve this symptom, and its etiology is unclear. Recently, we identified very rare single-nucleotide polymorphisms (SNPs) on ZNF806 and SART3 by exome sequencing in three patients with profoundly severe tardive dystonia. Here, we conducted an association study (case, N = 16 vs. control, N = 96) on the rarest SNP selected from each gene. The results showed that rs2287546 on SART3 was not related to tardive dystonia and that rs4953961 on ZNF806 was a heterozygote in all the subjects, implying the absence of a rare SNP in this locus. We found three other genomic regions with high similarity to the relevant region on ZNF806 by BLAT searches. This strongly suggested a misalignment error in this region in our previous exome sequence. In conclusion, ZNF806 and SART3 are unlikely to be related to tardive dystonia.

A Modified Delphi Consensus Study of the Screening, Diagnosis, and Treatment of Tardive Dyskinesia.

OBJECTIVE: A nominal group process followed by a modified Delphi method was used to survey expert opinions on best practices for tardive dyskinesia (TD) screening, diagnosis, and treatment and to identify areas lacking in clinical evidence. PARTICIPANTS: A steering committee of 11 TD experts met in nominal group format to prioritize questions to be addressed and identify core bibliographic materials and criteria for survey panelists. Of 60 invited experts, 29 (23 psychiatrists and 6 neurologists) agreed to participate. EVIDENCE: A targeted literature search of PubMed (search term: tardive dyskinesia) and recommendations of the steering committee were used to generate core bibliographic material. Inclusion criteria were as follows: (1) review articles, meta-analyses, guidelines, or clinical trials; (2) publication in English between 2007 and 2017; (3) > 3 pages in length; and (4) publication in key clinical journals with impact factors ≥ 2.0. Of 29 references that met these criteria, 18 achieved a score ≥ 5 (calculated as the number of steering committee votes multiplied by journal impact factor and number of citations divided by years since publication) and were included. CONSENSUS PROCESS: Two survey rounds were conducted anonymously through electronic media from November 2017 to January 2018; responses were collected, collated, and analyzed. Respondent agreement was defined a priori as unanimous (100%), consensus (75%-99%), or majority (50%-74%). For questions using a 5-point Likert scale, agreement was based on percentage of respondents choosing ≥ 4 ("agree completely" or "agree"). Round 1 survey included questions on TD screening, diagnosis, and treatment. Round 2 questions were refined per panelist feedback and excluded Round 1 questions with < 25% agreement and > 75% agreement (unless feedback suggested further investigation). CONCLUSIONS: Consensus was reached that (1) a brief, clinical assessment for TD should be performed at every clinical encounter in patients taking antipsychotics; (2) even mild movements in 1 body area may represent possible TD; (3) management requires an overall evaluation of treatment, including reassessment of antipsychotics and anticholinergics as well as consideration of vesicular monoamine transporter 2 (VMAT2) inhibitors; and (4) informed discussions with patients/caregivers are essential.

A probable case of movement disorder (Tardive dyskinesia) due to duloxetine treatment.

Tardive dyskinesia and tardive dystonia are caused by dopamine receptor blocking agents, mostly antipsychotics and sometimes antidepressants or calcium channel blockers. Duloxetine is a serotonin-noradrenaline reuptake inhibitor used in the treatment of diabetic neuropathic pain and fibromyalgia, as well as major depression. In this case, we aimed to discuss the tardive dyskinesia-like appearance of a patient using duloxetine due to fibromyalgia.

Neurostimulation in tardive dystonia/dyskinesia: A delayed start, sham stimulation-controlled randomized trial.

INTRODUCTION: Growing evidence suggests that pallidal deep brain stimulation represents a potential new therapeutic avenue in tardive dystonia/dyskinesia, but controlled and blinded randomized studies (RCT) are missing. The present RCT compares dystonia/dyskinesia severity of pallidal neurostimulation in patients with tardive dystonia using a delayed-start design paradigm. METHODS: Dystonia/dyskinesia severity was assessed via blinded videos following pallidal neurostimulation at 3 (blinded phase) and 6 months (open extension phase). Primary endpoint was the percentage change of dystonia severity (Burke-Fahn-Marsden-Dystonia-Rating-Scale, BFMDRS) at 3 months between active vs. sham neurostimulation using blinded-video assessment. Secondary endpoints comprised clinical rating scores for movement disorders. Clinicaltrials.gov NCT00331669. RESULTS: Twenty-five patients were randomized (1:1) to active (n = 12) or sham neurostimulation (n = 13). In the intention-to-treat analyses the between group difference of dystonia severity (BFMDRS) between active vs. sham stimulation was not significant at 3 months. Three months post-randomisation dystonia severity improved significantly within the neurostimulation by 22.8% and non-significantly within the sham group (12.0%) compared to their respective baseline severity. During the open-label extension with both groups being actively treated, significant and pronounced improvements of 41.5% were observed via blinded evaluation. Adverse events (n = 10) occurred in 10/25 of patients during the 6 months, mostly related to surgical implantation of the device; all resolved without sequelae. CONCLUSION: The primary endpoint of this randomized trial was not significant, most likely due to incomplete recruitment. However, pronounced improvements of most secondary endpoints at 3 and 6 months provide evidence for efficacy and safety of pallidal neurostimulation in tardive dystonia.

Deutetrabenazine: Treatment of hyperkinetic aspects of Huntington's disease, tardive dyskinesia and Tourette syndrome.

Deutetrabenazine is a derivative of tetrabenazine in which two trideuteromethoxy groups substitute two methoxy groups. The active metabolites of deutetrabenazine have a longer half-life than those of tetrabenazine, together with a greater overall absorption. However, the peak plasma concentrations are lower. Because of these pharmacokinetic differences, deutetrabenazine can be given twice daily, thus improving compliance. The lower peak concentrations may account for a lower incidence of some unwanted adverse effects. Unlike tetrabenazine, deutetrabenazine has no effect on the QT interval. Treatment with deutetrabenazine significantly improved chorea in Huntington's disease, the hyperkinetic features of tardive dyskinesia, and tics in Tourette syndrome. In all three conditions, deutetrabenazine produced an acceptable level of overall adverse effects without causing any severe adverse effects.