Short-term effects of tetrabenazine on chorea associated with Huntington's disease.

We sought to assess the short-term clinical effects of tetrabenazine (TBZ) on choreic movements in Huntington's disease patients. A total of 10 patients on stable doses of TBZ were enrolled in this observational study. Patients took their evening dose of TBZ and presented the next day to the Baylor College of Medicine Movement Disorders Clinic without taking the usual morning dose. They were assessed using the Unified Huntington's Disease Rating Scale (UHDRS) motor assessment and Beck Depression Inventory. The usual morning dose of TBZ was then administered and patients were followed with serial UHDRS motor examinations approximately every 2 hours until choreic movements subsided and then returned. TBZ decreased the UHDRS chorea score on average 42.4% +/- 17.8%. The duration of effect varied from a minimum of 3.2 hours to a maximum of 8.1 hours (mean = 5.4 +/- 1.3). No patient experienced an adverse event related to TBZ or its withdrawal. During short-term follow-up after a single dose, TBZ improves chorea for approximately 5 hours.     

A randomized,double‐blind,placebo‐controlled trial evaluating cysteamine in Huntington's disease

Background : Cysteamine has been demonstrated as potentially effective in numerous animal models of Huntington's disease. Methods : Ninety‐six patients with early‐stage Huntington's disease were randomized to 1200 mg delayed‐release cysteamine bitartrate or placebo daily for 18 months. The primary end point was the change from baseline in the UHDRS Total Motor Score. A linear mixed‐effects model for repeated measures was used to assess treatment effect, expressed as the least‐squares mean difference of cysteamine minus placebo, with negative values indicating less deterioration relative to placebo. Results : At 18 months, the treatment effect was not statistically significant — least‐squares mean difference, ‐1.5 ± 1.71 (P = 0.385) — although this did represent less mean deterioration from baseline for the treated group relative to placebo. Treatment with cysteamine was safe and well tolerated. Conclusions : Efficacy of cysteamine was not demonstrated in this study population of patients with Huntington's disease. Post hoc analyses indicate the need for definitive future studies. © 2017 International Parkinson and Movement Disorder Society     

Comparative cognitive effects of bilateral subthalamic stimulation and subcutaneous continuous infusion of apomorphine in Parkinson's disease.

Bilateral subthalamic deep brain stimulation (STN-DBS) and continuous subcutaneous infusion of apomorphine (APM-csi) can provide a comparable improvement on motor function in patients with advanced Parkinson's disease (PD), but the mechanisms by which both therapies exert their effects are different. We analyzed the cognitive effects of APM-csi. We also compared neuropsychological effects induced by STN-DBS and APM-csi in advanced PD to ascertain the neuropsychological aspects relevant in determining the therapeutic procedure that is the most appropriate in a particular patient. We studied 9 patients treated with STN-DBS and 7 patients with APM-csi. Neuropsychological measures included Rey's Auditory-Verbal Learning, Stroop, Trail Making, phonetic verbal fluency, and Judgment of Line Orientation tests. In the APM-csi group, significant changes were not observed in the neuropsychological tests performance. By contrast, in the STN-DBS group, moderate worsening was found in phonetic verbal fluency and Stroop Naming scores that was partially reversible at long-term follow-up and did not have consequences on regular activities. Consequently, these findings could be interpreted as being not relevant in deciding the most suitable treatment in a given patient.     

A randomized,double‐blind,placebo‐controlled trial of pridopidine in Huntington's disease

We examined the effects of 3 dosages of pridopidine, a dopamine‐stabilizing compound, on motor function and other features of Huntington's disease, with additional evaluation of its safety and tolerability. This was a randomized, double‐blind, placebo‐controlled trial in outpatient neurology clinics at 27 sites in the United States and Canada. Two hundred twenty‐seven subjects enrolled from October 24, 2009, to May 10, 2010. The intervention was pridopidine, either 20 (n=56), 45 (n=55), or 90 (n=58) mg daily for 12 weeks or matching placebo (n=58). The primary outcome measure was the change from baseline to week 12 in the Modified Motor Score, a subset of the Unified Huntington's Disease Rating Scale Total Motor Score. Measures of safety and tolerability included adverse events and trial completion on the assigned dosage. After 12 weeks, the treatment effect (relative to placebo, where negative values indicate improvement) of pridopidine 90 mg/day on the Modified Motor Score was ?1.2 points (95% confidence interval [CI], ?2.5 to 0.1 points; P = .08). The effect on the Total Motor Score was ?2.8 points (95% CI, ?5.4 to ?0.1 points; nominal P = .04). No significant effects were seen in secondary outcome measures with any of the active dosages. Pridopidine was generally well tolerated. Although the primary analysis did not demonstrate a statistically significant treatment effect, the overall results suggest that pridopidine may improve motor function in Huntington's disease. The 90 mg/day dosage appears worthy of further study. Pridopidine was well tolerated. © 2013 International Parkinson and Movement Disorder Society     

Open-label pilot study of levetiracetam (Keppra) for the treatment of chorea in Huntington's disease.

The objective of this study is to evaluate the tolerability and preliminary efficacy of levetiracetam (LEV) in reducing chorea in Huntington's disease (HD) patients in a prospective open-label pilot study. Nine HD patients with chorea were treated with LEV in doses up to 3,000 mg/day for up to 48 days. The primary endpoint measure was the Unified Huntington's Disease Rating Scale (UHDRS) chorea subscore. The mean dose (+/-SD) of LEV at endpoint was 2,583.3 +/- 1,020.6 mg/day. Mean UHDRS chorea score decreased from 12.6 +/- 3.0 at baseline to 6.7 +/- 4.3 at endpoint (P = 0.01). There was no significant change in UHDRS total motor scores (38.8 +/- 11.4 at baseline and 33.6 +/- 26.7 at endpoint; P = 0.24). Somnolence contributed to a 33% drop-out rate, and 3 patients developed Parkinsonism. Results of this open label study suggest that LEV may be efficacious in reducing chorea in HD patients.     

Intravenous flumazenil for Parkinson's disease: a single dose, double blind, placebo controlled, cross-over trial.

Flumazenil is a short-acting intravenously administered gamma-aminobutyric acid (GABA) antagonist used to reverse the effects of benzodiazepines. Based upon current basal ganglion models in Parkinson's disease (PD), flumazenil could normalize neuronal signaling at several different locations. We conducted a double-blind, placebo controlled, single dose, cross-over trial of flumazenil and placebo in 16 subjects with PD. Subjects were primarily assessed with serial tapping tests (1 minute for each hand) at 15-minute intervals for 90 minutes after infusion. Secondary assessments included the Unified Parkinson's Disease Rating Scale (UPDRS) Motor part at baseline and 45 minutes after infusion, and global impressions. Subjects then underwent a 90-minute washout and entered the opposite arm of the cross-over. Change in tapping speed compared to baseline improved throughout the 90-minute period (P < 0.0001) and at each individual time (P < 0.01), except for 15 minutes status after infusion, with flumazenil compared to placebo. UPDRS scores tended to improve more on drug, but this finding was not significant. The medication was well tolerated. The most common adverse event on drug was a sense of "light-headedness" or "dizziness." GABA antagonists represent a novel potential treatment class for PD.     

Continuous subcutaneous apomorphine infusion in Parkinson's disease patients with cognitive dysfunction: A retrospective long-term follow-up study

IntroductionContinuous apomorphine infusion (CAI) is an advanced therapy in fluctuating Parkinson's disease (PD). The use of CAI is controversial in PD patients with cognitive dysfunction including visual hallucinations (VHs), and orthostatic hypotension (OH). This study was set-up to analyze the effectiveness and safety of CAI in elderly PD patients with cognitive dysfunction.MethodsThis new-user cohort study identified fluctuating PD patients who started CAI treatment at the rehabilitation unit of Parkinson Expertise Center (RU-PEC) Groningen, from November 2004 until 2016. Efficacy and safety data included motor function, cognitive status, OH and VHs, and was analyzed retrospectively. Pre-existent non-motor symptoms were treated optimally before starting CAI.ResultsForty-five fluctuating PD patients (age: 70.9 ± 8.1 yrs, disease duration: 10.8 ± 4.8 yrs) were identified, with pre-existing cognitive dysfunction, VHs (71%), and OH (26%). During the stay at RU-PEC (median 52 days) apomorphine was successfully titrated without worsening of pre-existing VHs and OH. The mean daily apomorphine dose was 66 ± 28 mg, accompanied by a reduction of levodopa-equivalent daily dose (LEDD) with 17%. The duration of ON-time and OFF-time significantly improved with +2.36 h (25%) and −1.66 h (−45%), respectively, while dyskinesia duration did not change. During long-term follow-up (median of 26 months) VHs and OH worsened in 9 and 4 patients, which necessitated discontinuation in 4 cases.ConclusionThis study demonstrates that CAI is also an effective treatment in advanced PD patients with concomitant cognitive dysfunction including VHs and OH, provided that these comorbidities are treated adequately as well.     

Safety of entacapone and apomorphine coadministration in levodopa-treated Parkinson's disease patients: pharmacokinetic and pharmacodynamic results of a multicenter, double-blind, placebo-controlled, cross-over study.

We investigated whether administration of the catechol-O-methyl transferase (COMT) inhibitor entacapone, at doses of 200 mg and 400 mg, alters the pharmacokinetics of apomorphine in Parkinson's disease patients experiencing severe motor fluctuations. In addition, the pharmacodynamics and safety of entacapone and apomorphine coadministration in these patients were examined. The study followed a three-sequence, three-period, crossover design. Patients were randomly assigned to one of three sequences that included single oral doses of entacapone 200 mg, entacapone 400 mg, and placebo in a predefined order. On 3 separate test days, study treatment was administered before apomorphine. The study evaluations (pharmacokinetics, tapping test, and dyskinesia evaluation [Abnormal Involuntary Movements Scale - AIMS]) were performed on these days. Furthermore, Unified Parkinson Disease Rating Scale (UPDRS) scores were evaluated at baseline and study end. Pharmacokinetic parameters for apomorphine (C(max), AUC, t(max), t(1/2)) were unchanged by the administration of entacapone, and changes in both the tapping test and AIMS score were similar with all treatments (entacapone 200 mg, entacapone 400 mg, and placebo). There was no significant difference in mean total UPDRS scores between baseline and study end. The administration of entacapone did not change the pharmacokinetic or pharmacodynamic effects of apomorphine in these patients or prolong the clinical effect of apomorphine. Thus, apomorphine may be safely administered to patients receiving therapy with levodopa and entacapone, providing a useful addition to treatment for patients with advanced Parkinson's disease.     

A double blind trial of lithium carbonate and haloperidol in Huntington's chorea.

Six patients with a family history of Huntington's chorea (HC) participated in a double blind crossover trial involving four treatments--lithium carbonate, haloperidol, lithium carbonate and haloperidol, and placebo. Each treatment was administered for three weeks and, at the end of each treatment period, assessments were made of chorea and a number of psychological variables. None of the treatments significantly affected chorea measurements. With regard to the psychological variables, the levels of irritability, the frequency of angry outbursts and depression did appear to be affected in some patients by the treatment. Three patients improved on a combination of lithium carbonate and haloperidol while the remaining three did not. Haloperidol alone significantly raised depression ratings above levels for other treatments including placebo. It is suggested that lithium carbonate and haloperidol together should be seriously considered in the treatment of HC when patients are excessively irritable and impulsive.     

Pharmacological treatment of chorea in Huntington's disease–good clinical practice versus evidence‐based guideline

Recently, the American Academy of Neurology published an evidence‐based guideline for the pharmacological treatment of chorea in Huntington's disease. Although the progress in medical care because of the implementation of criteria of evidence‐based medicine is undisputed, the guideline classifies the level of evidence for drugs to reduce chorea based on anchors in the Unified Huntington's Disease Rating Scale‐Total Motor Score chorea sum score, which were chosen arbitrarily and do not reflect validated or generally accepted levels of clinical relevance. Thus, the guideline faces several serious limitations and delivers clinical recommendations that do not represent current clinical practice; these are reviewed in detail, and arguments are presented why these recommendations should not be followed. To remedy the lack of evidence‐based recommendations and provide guidance to a pragmatic symptomatic therapy of chorea in HD, a flow‐chart pathway that follows currently established clinical standards based on expert opinion is presented. © 2013 Movement Disorder Society     

Ultrasound treatment of cutaneous side‐effects of infused apomorphine: A randomized controlled pilot study

Apomorphine hydrochloride is a dopamine agonist used in the treatment of advanced Parkinson's disease. Its administration by subcutaneous infusions is associated with the development of nodules that may interfere with absorption of the drug. This pilot study assessed the effectiveness of ultrasound (US) in the treatment of these nodules. Twelve participants were randomly assigned to receive a course of real or sham US on an area judged unsuitable for infusion. Following treatment, no significant change was observed in measures of tissue hardness and tenderness. However, 5 of 6 participants receiving real US rated the treated area suitable for infusion compared with the 1 of 6 receiving sham US. Sonographic appearance improved in both groups, but more substantially in the real US group. Power calculations suggest a total sample size of 30 would be required to establish statistical significance. A full‐scale study of the effectiveness of therapeutic US in the treatment of apomorphine nodules is warranted. © 2008 Movement Disorder Society     

Prevalence of Huntington's disease in Southern Sardinia,Italy

BackgroundThe frequency of Huntington's disease (HD) may vary considerably, with higher estimates in non Asian populations. In Italy, two recent studies performed in Ferrara county and Molise provided different prevalence estimates, varying from 4.2 × 10⁵ to 10.8 × 10⁵. Here we present a study performed in the Southern part of Sardinia, a large Italian mediterranean island that is considered a genetic isolate.MethodsThe study area included the two neighbouring counties of South Sardinia and Cagliari with 353,830 and 431,955 inhabitants respectively on December 31st, 2017 (prevalence date). Case-patients were ascertained through multiple sources in Sardinia and Italy.ResultsWe identified 54 individuals with HD, of whom 47 were alive on prevalence date. The resulting prevalence rate was 5.98 × 10⁵ in the overall study area, however with marked variations between South Sardinia and Cagliari (9.6 × 10⁵ vs. 3.0 × 10⁵, p = 0.02). In the two study areas, we found similar CAG repeat length in normal alleles (17.5 ± 2.1 vs. 17.7 ± 2.2, p = 0.5).ConclusionsThe overall prevalence of HD in Sardinia is close to the correspondent estimates in Europeans. Our findings also highlighted the possibility of local microgeographic variations in the epidemiology of HD.     

Diffusion tensor imaging in presymptomatic and early Huntington's disease: Selective white matter pathology and its relationship to clinical measures.

Atrophy of cortical and subcortical gray matter is apparent in Huntington's disease (HD) before symptoms manifest. We hypothesized that the white matter (WM) connecting cortical and subcortical regions must also be affected early and that select clinical symptoms were related to systems degeneration. We used diffusion tensor magnetic resonance imaging (DTI) to examine the regional nature of WM abnormalities in early HD, including the preclinical period, and to determine whether regional changes correlated with clinical features. We studied individuals in early stages (HD), presymptomatic individuals known to carry the genetic mutation that causes HD (Pre-HD), and matched healthy controls. DTI indices of tissue integrity were obtained from several regions of interest, including the corpus callosum (CC), internal capsule (IC), and basal ganglia, were compared across groups by t tests, and were correlated to cognitive and clinical measures. WM alterations were found throughout the CC, in the anterior and posterior limbs of the IC, and in frontal subcortical WM in HD subjects, supporting the selective involvement of the pyramidal tracts in HD; a similar distribution of changes was seen in Pre-HD subjects, supporting presymptomatic alterations. There was a significant relationship between select DTI measures and cognitive performance. Alterations in diffusion indices were also seen in the striatum that were independent of atrophy. Our findings support that WM alterations occur very early in HD. The distribution of the changes suggests that these changes contribute to the disruption of pyramidal and extrapyramidal circuits and also support a role of compromised cortical circuitry in early cognitive and subtle motor impairment during the preclinical stages of HD.     

HD‐CAB: A cognitive assessment battery for clinical trials in Huntington's disease1,2,3

Cognitive dysfunction is central to Huntington's disease (HD) and undermines quality of life. Clinical trials are now targeting cognitive outcomes in HD; however, no cognitive battery has been optimized for HD clinical trials. We evaluated 16 cognitive tests in a 20‐site, five‐country, observational study designed to mimic aspects of a clinical trial (e.g., data collection managed by a contract research organization, repeated testing, prespecified statistical analyses). Fifty‐five early HD, 103 premanifest HD (pre‐HD), and 105 controls were tested at visit 1, visit 2 (1‐3 days later), and visit 3 (5‐7 weeks after visit 1). For inclusion in a recommended battery, tests were evaluated for sensitivity, practice effects, reliability, domain coverage, feasibility, and tolerability. Most tests differentiated controls from pre‐HD and early HD and showed excellent psychometric properties. We selected six tests to constitute the Huntington's Disease Cognitive Assessment Battery (HD‐CAB): Symbol Digit Modalities Test, Paced Tapping, One Touch Stockings of Cambridge (abbreviated), Emotion Recognition, Trail Making B, and the Hopkins Verbal Learning Test. These tests demonstrated sensitivity to disease status (Cohen's d effect sizes: early HD= ?1.38 to ?1.90 and pre‐HD= ?0.41 to ?0.78), and acceptable reliability (r's 0.73‐0.93). A composite score yielded large effect sizes (early HD = ?2.44 and pre‐HD = ?0.87) and high reliability (r = 0.95). HD‐CAB is the first cognitive battery designed specifically for use in late premanifest and early HD clinical trials. Adoption of the HD‐CAB will facilitate evaluation of treatments to improve cognition in HD. © 2014 International Parkinson and Movement Disorder Society     

Transdermal apomorphine permeation from microemulsions: a new treatment in Parkinson's disease.

We studied absorption, efficacy, and tolerability in Parkinson's disease (PD) of a new preparation of apomorphine included in a microemulsion and administered by transdermal route (Apo-MTD). Twenty-one PD patients were treated with levodopa plus oral dopamine-agonists (T0), with levodopa alone (T1), finally with levodopa plus Apo-MTD (T2). Apo-MTD provided therapeutic plasma levels for many hours, improved Unified Parkinson's Disease Rating Scale III scores, and reduced total duration of off periods compared to T0 and T1. We concluded that Apo-MTD is absorbed and demonstrates clinical efficacy and long action. Therefore, it seems a promising add-on treatment for uncontrolled prolonged off phases in PD patients, but chronic tolerability needs further study.     

A pilot study using nabilone for symptomatic treatment in Huntington's disease

Pilot study of nabilone in Huntington's disease (HD). Double‐blind, placebo‐controlled, cross‐over study of nabilone versus placebo. Primary outcome, Unified Huntington's Disease Rating Scale (UHDRS) total motor score. Secondary measures: UHDRS subsections for chorea, cognition and behavior, and neuropsychiatric inventory (NPI). 44 randomized patients received either nabilone (1 or 2 mg) followed by placebo (n = 22), or placebo followed by nabilone (n = 22). Recruiting was straightforward. Nabilone safe and well tolerated, no psychotic episodes. Assessment of either dose of nabilone versus placebo showed a treatment difference of 0.86 (95% CI: ?1.8 to 3.52) for total motor score; 1.68 (95% CI: 0.44 to 2.92) for chorea; 3.57 (95% CI: ?3.41 to 10.55) for UHDRS cognition; 4.01 (95% CI: ?0.11 to 8.13) for UHDRS behavior, and 6.43 (95% CI: 0.2 to 12.66) for the NPI. Larger longer RCT of nabilone in HD is feasible and warranted. © 2009 Movement Disorder Society     

Duodenal levodopa infusion for advanced Parkinson's disease: 12-month treatment outcome.

We assessed prospectively clinical and quality of life changes in 9 patients with Parkinson's disease (PD; H&Y > or = 3) with severe motor fluctuations and dyskinesia who started continuous daily levodopa duodenal infusion through percutaneous endoscopic gastrostomy. Seven patients completed the follow-up period. Duration of "off" periods and time with disabling dyskinesia shortened significantly in all patients (P < 0.01). Total daily dose of levodopa infused did not differ from baseline equivalents. There were significant improvements in UPDRS-II (activities of daily living) and -IV (motor complications) in the "on" condition (P < 0.02), and in four PDQ-39 domains (mobility, activities of daily living, stigma, bodily discomfort; P < 0.05). Two patients withdrew for adverse events. Our results demonstrate that a satisfactory therapeutic window can be achieved and maintained for several months in advanced PD patients.