Fatigue Impacts Quality of Life in People with Spinocerebellar Ataxias

BACKGROUND

Fatigue is a prevalent and debilitating symptom in neurological disorders, including spinocerebellar ataxias (SCAs). However, the risk factors of fatigue in the SCAs as well as its impact have not been well investigated.

OBJECTIVES

To study the prevalence of fatigue in SCAs, the factors contributing to fatigue, and the influence of fatigue on quality of life.

METHODS

Fatigue was assessed in 418 participants with SCA1, SCA2, SCA3, and SCA6 from the Clinical Research Consortium for the Study of Cerebellar Ataxia using the Fatigue Severity Scale. We conducted multi-variable linear regression models to examine the factors contributing to fatigue as well as the association between fatigue and quality of life.

RESULTS

Fatigue was most prevalent in SCA3 (52.6%), followed by SCA1 (36.7%), SCA6 (35.7%), and SCA2 (35.6%). SCA cases with fatigue had more severe ataxia and worse depressive symptoms. In SCA3, those with fatigue had a longer disease duration and longer pathological CAG repeat numbers. In multi-variable models, depressive symptoms, but not ataxia severity, were associated with more severe fatigue. Fatigue, independent of ataxia and depression, contributed to worse quality of life in SCA3 and SCA6 at baseline, and fatigue continued affecting quality of life throughout the disease course in all types of SCA.

CONCLUSIONS

Fatigue is a common symptom in SCAs and is closely related to depression. Fatigue significantly impacts patients' quality of life. Therefore, screening for fatigue should be considered a part of standard clinical care for SCAs.

The Cerebellar Cognitive Affective/Schmahmann Syndrome Scale in Spinocerebellar Ataxias

The Cerebellar Cognitive Affective/Schmahmann Syndrome (CCAS) manifests as impaired executive control, linguistic processing, visual spatial function, and affect regulation. The CCAS has been described in the spinocerebellar ataxias (SCAs), but its prevalence is unknown. We analyzed results of the CCAS/Schmahmann Scale (CCAS-S), developed to detect and quantify CCAS, in two natural history studies of 309 individuals Symptomatic for SCA1, SCA2, SCA3, SCA6, SCA7, or SCA8, 26 individuals Pre-symptomatic for SCA1 or SCA3, and 37 Controls. We compared total raw scores, domain scores, and total fail scores between Symptomatic, Pre-symptomatic, and Control cohorts, and between SCA types. We calculated scale sensitivity and selectivity based on CCAS category designation among Symptomatic individuals and Controls, and correlated CCAS-S performance against age and education, and in Symptomatic patients, against genetic repeat length, onset age, disease duration, motor ataxia, depression, and fatigue. Definite CCAS was identified in 46% of the Symptomatic group. False positive rate among Controls was 5.4%. Symptomatic individuals had poorer global CCAS-S performance than Controls, accounting for age and education. The domains of semantic fluency, phonemic fluency, and category switching that tap executive function and linguistic processing consistently separated Symptomatic individuals from Controls. CCAS-S scores correlated most closely with motor ataxia. Controls were similar to Pre-symptomatic individuals whose nearness to symptom onset was unknown. The use of the CCAS-S identifies a high CCAS prevalence in a large cohort of SCA patients, underscoring the utility of the scale and the notion that the CCAS is the third cornerstone of clinical ataxiology.

The S-Factor, a New Measure of Disease Severity in Spinocerebellar Ataxia: Findings and Implications

Spinocerebellar ataxias (SCAs) are progressive neurodegenerative disorders, but there is no metric that predicts disease severity over time. We hypothesized that by developing a new metric, the Severity Factor (S-Factor) using immutable disease parameters, it would be possible to capture disease severity independent of clinical rating scales. Extracting data from the CRC-SCA and READISCA natural history studies, we calculated the S-Factor for 438 participants with symptomatic SCA1, SCA2, SCA3, or SCA6, as follows: ((length of CAG repeat expansion - maximum normal repeat length) /maximum normal repeat length) × (current age - age at disease onset) × 10). Within each SCA type, the S-Factor at the first Scale for the Assessment and Rating of Ataxia (SARA) visit (baseline) was correlated against scores on SARA and other motor and cognitive assessments. In 281 participants with longitudinal data, the slope of the S-Factor over time was correlated against slopes of scores on SARA and other motor rating scales. At baseline, the S-Factor showed moderate-to-strong correlations with SARA and other motor rating scales at the group level, but not with cognitive performance. Longitudinally the S-Factor slope showed no consistent association with the slope of performance on motor scales. Approximately 30% of SARA slopes reflected a trend of non-progression in motor symptoms. The S-Factor is an observer-independent metric of disease burden in SCAs. It may be useful at the group level to compare cohorts at baseline in clinical studies. Derivation and examination of the S-factor highlighted challenges in the use of clinical rating scales in this population.

Current and Emerging Treatment Modalities for Spinocerebellar Ataxias

INTRODUCTION

Spinocerebellar ataxias (SCA) are a group of rare neurodegenerative diseases that dramatically affect the lives of affected individuals and their families. Despite having a clear understanding of SCA's etiology, there are no current symptomatic or neuroprotective treatments approved by the FDA.

AREAS COVERED

Research efforts have greatly expanded the possibilities for potential treatments, including both pharmacological and non-pharmacological interventions. Great attention is also being given to novel therapeutics based in gene therapy, neurostimulation, and molecular targeting. This review article will address the current advances in the treatment of SCA and what potential interventions are on the horizon.

EXPERT OPINION

SCA is a highly complex and multifaceted disease family with the majority of research emphasizing symptomatic pharmacologic therapies. As pre-clinical trials for SCA and clinical trials for other neurodegenerative conditions illuminate the efficacy of disease modifying therapies such as AAV-mediated gene therapy and ASOs, the potential for addressing SCA at the pre-symptomatic stage is increasingly promising.

Emerging therapies in Friedreich's Ataxia

INTRODUCTION

Friedreich's ataxia (FRDA) is a progressive, neurodegenerative disease that results in gait and limb ataxia, diabetes, cardiac hypertrophy, and scoliosis. At the cellular level, FRDA results in the deficiency of frataxin, a mitochondrial protein that plays a vital role in iron homeostasis and amelioration of oxidative stress. No cure currently exists for FRDA, but exciting therapeutic developments which target different parts of the pathological cascade are on the horizon.

AREAS COVERED

Areas covered include past and emerging therapies for FRDA, including antioxidants and mitochondrial-related agents, nuclear factor erythroid-derived 2-related factor 2 (Nrf2) activators, deuterated polyunsaturated fatty acids, iron chelators, histone deacetylase (HDAC) inhibitors, trans-activator of transcription (TAT)-frataxin, interferon gamma (IFNγ), erythropoietin, resveratrol, gene therapy, and anti-sense oligonucleotides (ASOs), among others.

EXPERT OPINION

While drug discovery has been challenging, new and exciting prospective treatments for FRDA are currently on the horizon, including pharmaceutical agents and gene therapy. Agents that enhance mitochondrial function, such as Nrf2 activators, dPUFAs and catalytic antioxidants, as well as novel methods of frataxin augmentation and genetic modulation will hopefully provide treatment for this devastating disease.

Prospective Home-use Study on Non-invasive Neuromodulation Therapy for Essential Tremor

Highlights

This prospective study is one of the largest clinical trials in essential tremor to date. Study findings suggest that individualized non-invasive neuromodulation therapy used repeatedly at home over three months results in safe and effective hand tremor reduction and improves quality of life for many essential tremor patients.

Background

Two previous randomized, controlled, single-session trials demonstrated efficacy of non-invasive neuromodulation therapy targeting the median and radial nerves for reducing hand tremor. This current study evaluated efficacy and safety of the therapy over three months of repeated home use.

Methods

This was a prospective, open-label, post-clearance, single-arm study with 263 patients enrolled across 26 sites. Patients were instructed to use the therapy twice daily for three months. Pre-specified co-primary endpoints were improvements on clinician-rated Tremor Research Group Essential Tremor Rating Assessment Scale (TETRAS) and patient-rated Bain & Findley Activities of Daily Living (BF-ADL) dominant hand scores. Other endpoints included improvement in the tremor power detected by an accelerometer on the therapeutic device, Clinical and Patient Global Impression scores (CGI-I, PGI-I), and Quality of Life in Essential Tremor (QUEST) survey.

Results

205 patients completed the study. The co-primary endpoints were met (p≪0.0001), with 62% (TETRAS) and 68% (BF-ADL) of 'severe' or 'moderate' patients improving to 'mild' or 'slight'. Clinicians (CGI-I) reported improvement in 68% of patients, 60% (PGI-I) of patients reported improvement, and QUEST improved (p = 0.0019). Wrist-worn accelerometer recordings before and after 21,806 therapy sessions showed that 92% of patients improved, and 54% of patients experienced ≥50% improvement in tremor power. Device-related adverse events (e.g., wrist discomfort, skin irritation, pain) occurred in 18% of patients. No device-related serious adverse events were reported.

Discussion

This study suggests that non-invasive neuromodulation therapy used repeatedly at home over three months results in safe and effective hand tremor reduction in many essential tremor patients.

Test-retest reliability of the Friedreich's ataxia rating scale

The modified Friedreich Ataxia Rating Scale (mFARS) is a disease specific, exam-based neurological rating scale commonly used as a outcome measure in clinical trials. While extensive clinimetric testing indicates it's validity in measuring disease progression, formal test-retest reliability was lacking. To fill this gap, we acquired results from screening and baseline visits of several large clinical trials and calculated intraclass correlation coefficients, coefficients of variance, standard error, and the minimally detectable changes. This study demonstrated excellent test-retest reliability of the mFARS, and it's upright stability subscore.

Orphan Drugs In Development For The Treatment Of Friedreich's Ataxia: Focus On Omaveloxolone

Friedreich’s Ataxia (FRDA) is a devastating and progressive ataxia, marked by mitochondrial dysfunction and oxidative stress. Nrf2 activators such as omaveloxolone (Omav) modulate antioxidative mechanisms, and thus may be viable therapeutic agents in FRDA.

Management of Early Parkinson Disease

Early Parkinson disease is the approximate time period between initial diagnosis and the onset of motor fluctuations. Treatment requires an integrative approach, including identification of motor and nonmotor symptoms, choice of pharmacologic treatment, and emphasis on exercise. Patients should be treated for motor symptoms, whereas medications may be delayed for milder symptoms. The choice of treatment in patients with early Parkinson disease must be weighed against financial considerations, ease of administration, and potential long-term adverse events. Nonmotor symptoms should also be identified and treated. Exercise is an important component for treatment of Parkinson disease at any stage.

Comprehensive systematic review summary: Treatment of cerebellar motor dysfunction and ataxia: Report of the Guideline Development, Dissemination, and Implementation Subcommittee of the American Academy of Neurology

OBJECTIVE

To systematically review evidence regarding ataxia treatment.

METHODS

A comprehensive systematic review was performed according to American Academy of Neurology methodology.

CONCLUSIONS

For patients with episodic ataxia type 2, 4-aminopyridine 15 mg/d probably reduces ataxia attack frequency over 3 months (1 Class I study). For patients with ataxia of mixed etiology, riluzole probably improves ataxia signs at 8 weeks (1 Class I study). For patients with Friedreich ataxia or spinocerebellar ataxia (SCA), riluzole probably improves ataxia signs at 12 months (1 Class I study). For patients with SCA type 3, valproic acid 1,200 mg/d possibly improves ataxia at 12 weeks. For patients with spinocerebellar degeneration, thyrotropin-releasing hormone possibly improves some ataxia signs over 10 to 14 days (1 Class II study). For patients with SCA type 3 who are ambulatory, lithium probably does not improve signs of ataxia over 48 weeks (1 Class I study). For patients with Friedreich ataxia, deferiprone possibly worsens ataxia signs over 6 months (1 Class II study). Data are insufficient to support or refute the use of numerous agents. For nonpharmacologic options, in patients with degenerative ataxias, 4-week inpatient rehabilitation probably improves ataxia and function (1 Class I study); transcranial magnetic stimulation possibly improves cerebellar motor signs at 21 days (1 Class II study). For patients with multiple sclerosis-associated ataxia, the addition of pressure splints possibly has no additional benefit compared with neuromuscular rehabilitation alone (1 Class II study). Data are insufficient to support or refute use of stochastic whole-body vibration therapy (1 Class III study).

A fixed-dose, dose-response study of ropinirole prolonged release in early stage Parkinson's disease

AIM

This Phase IV, double-blind, randomized, parallel-group study characterized the dose-response and tolerability of fixed doses of ropinirole prolonged release (PR).

PATIENTS & METHODS

Subjects with early Parkinson's disease (PD) received placebo or ropinirole PR 2, 4, 8, 12 or 24 mg once daily, up-titrated to randomized or highest tolerated dose, maintained for 4 weeks.

RESULTS

The primary end point was not met (change from baseline in Unified PD Rating Scale motor score). However, because the data were not normally distributed, prespecified nonparametric analysis of covariance suggested ropinirole PR (8 and 12 mg/day) was effective in treating motor symptoms. The adverse event profile was consistent with the known safety profile of ropinirole PR. There was no impulse control disorder reported. Although a higher than previously reported rate of sudden onset of sleep events was reported, these were not dose dependent and were likely to have been influenced by the method of data collection.

CONCLUSION

The adverse event profile was consistent with the known safety profile of ropinirole PR and ropinirole PR (8 or 12 mg/day) improved motor symptoms of early PD.

A randomized, fixed-dose, dose-response study of ropinirole prolonged release in advanced Parkinson's disease

AIM

This Phase IV, double-blind, randomized, parallel-group study characterized the dose-response and tolerability of fixed doses of ropinirole prolonged release (PR) in subjects with advanced Parkinson's disease.

PATIENTS & METHODS

Subjects receiving concomitant l-dopa received once-daily ropinirole PR 4, 8, 12, 16 or 24 mg, or placebo, up-titrated for 13 weeks, maintained for 4 weeks.

RESULTS

At maintenance period week 4, ropinirole PR significantly reduced total awake 'Off-time' (16 mg; p = 0.027); increased absolute awake time spent 'On' without troublesome dyskinesia from baseline versus placebo (8 mg; p = 0.036); improved Unified Parkinson's Disease Rating Scale motor scores versus placebo (all doses; p = 0.005-0.016). Incidence of adverse events was similar between treatment groups; no dose-related trends were observed.

CONCLUSION

Ropinirole PR (16 mg) reduced 'Off-time' with 8 mg the likely lowest maximally effective dose, and the safety profile was consistent with previous studies.

Emerging therapies in Friedreich's ataxia

Friedreich's ataxia (FRDA) is an inherited, progressive neurodegenerative disease that typically affects teenagers and young adults. Therapeutic strategies and disease insight have expanded rapidly over recent years, leading to hope for the FRDA population. There is currently no US FDA-approved treatment for FRDA, but advances in research of its pathogenesis have led to clinical trials of potential treatments. This article reviews emerging therapies and discusses future perspectives, including the need for more precise measures for detecting changes in neurologic symptoms as well as a disease-modifying agent.

Occupational Characteristics and Patterns as Risk Factors for Parkinson's Disease: A Case Control Study

BACKGROUND

Associations have been reported between the risk of Parkinson's disease (PD) and employment in certain fields. Most studies have focused on toxic exposures as potential causal explanations. However, PD also has been associated with personality characteristics that may influence occupational choices and patterns.

OBJECTIVE

This study evaluates the role of personality as indicated by occupational choices and employment patterns in the risk for PD.

METHODS

In-person interviews were conducted to assess occupational histories and early-adult personality indicators among 89 PD patients and 99 controls.

RESULTS

PD cases had fewer lifetime jobs than controls (mean for cases = 4.38 ± 2.20; mean for controls = 5.00 ± 2.26; p = 0.03). Among women, PD was positively associated with more complex work with people (OR = 1.45, 95% CI 1.12-1.89), representing a 95% increased risk for PD comparing women with the greatest complexity of work with those requiring the least complexity of work with people. Women PD cases also performed less complex work with things compared with controls (OR = 0.69 (95% CI 0.53-0.90)), translating into a 13-fold increased risk for PD among women whose work involved the least complex work with things compared with the most. The numbers of jobs and job types were associated with taking more activity risks as a young-adult (r = 0.19, p = 0.02; r = 0.26, p = 0.001, respectively).

CONCLUSIONS

Cases with PD held fewer lifetime jobs compared with controls. Occupational complexity was associated with the risk for PD among women, but not men. Further consideration of the possible influence of personality on occupational choices is warranted.

Critical appraisal of rotigotine transdermal system in management of Parkinson's disease and restless legs syndrome - patient considerations

Rotigotine (RTG) is a dopamine agonist that is used as mono and adjunct therapy to treat Parkinson’s disease, and as therapy for moderate-to-severe restless legs syndrome. RTG is the only dopamine agonist currently available as a 24-hour/day transdermal system, providing once-a-day dosing. As a transdermal patch, RTG bypasses the gastrointestinal tract, making it a treatment option for patients with dysphagia. The use of RTG also avoids the need to schedule administration of medication around meals. This review provides a critical appraisal of RTG as treatment of Parkinson’s disease and RLS.

Humoral factors in ALS patients during disease progression

BACKGROUND

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease affecting upper and lower motor neurons in the CNS and leading to paralysis and death. There are currently no effective treatments for ALS due to the complexity and heterogeneity of factors involved in motor neuron degeneration. A complex of interrelated effectors have been identified in ALS, yet systemic factors indicating and/or reflecting pathological disease developments are uncertain. The purpose of the study was to identify humoral effectors as potential biomarkers during disease progression.

METHODS

Thirteen clinically definite ALS patients and seven non-neurological controls enrolled in the study. Peripheral blood samples were obtained from each ALS patient and control at two visits separated by 6 months. The Revised ALS Functional Rating Scale (ALSFRS-R) was used to evaluate overall ALS-patient functional status at each visit. Eleven humoral factors were analyzed in sera. Cytokine levels (GM-CSF, IL-1β, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, and TNF-α) were determined using the Bio-Rad Bio-Plex® Luminex 200 multiplex assay system. Nitrite, a breakdown product of NO, was quantified using a Griess Reagent System. Glutathione (GSH) concentrations were measured using a Glutathione Fluorometric Assay Kit.

RESULTS

ALS patients had ALSFRS-R scores of 30.5 ± 1.9 on their first visit and 27.3 ± 2.7 on the second visit, indicating slight disease progression. Serum multiplex cytokine panels revealed statistically significant changes in IL-2, IL-5, IL-6, and IL-8 levels in ALS patients depending on disease status at each visit. Nitrite serum levels trended upwards in ALS patients while serum GSH concentrations were drastically decreased in sera from ALS patients versus controls at both visits.

CONCLUSIONS

Our results demonstrated a systemic pro-inflammatory state and impaired antioxidant system in ALS patients during disease progression. Increased levels of pro-inflammatory IL-6, IL-8, and nitrite and significantly decreased endogenous antioxidant GSH levels could identify these humoral constituents as systemic biomarkers for ALS. However, systemic changes in IL-2, IL-5, and IL-6 levels determined between visits in ALS patients might indicate adaptive immune system responses dependent on current disease stage. These novel findings, showing dynamic changes in humoral effectors during disease progression, could be important for development of an effective treatment for ALS.

Randomized, controlled pilot trial of solifenacin succinate for overactive bladder in Parkinson's disease

OBJECTIVE

To evaluate the efficacy of solifenacin succinate in Parkinson's disease (PD) patients suffering from overactive bladder (OAB).

BACKGROUND

Urinary dysfunction is a commonly encountered non-motor feature in PD that significantly impacts patient quality of life.

DESIGN/METHODS

This was a double-blind, randomized, placebo-controlled, 3-site study with an open label extension phase to determine the efficacy of solifenacin succinate in idiopathic PD patients with OAB. Patients were randomized to receive solifenacin succinate 5-10 mg daily or placebo for 12 weeks followed by an 8-week open label extension. The primary outcome measure was the change in the mean number of micturitions per 24 h period. Secondary outcome measures included the change in the mean number of urinary incontinence episodes and the mean number of nocturia episodes.

RESULTS

Twenty-three patients were randomized in the study. There was no significant improvement in the primary outcome measure in the double-blind phase, but there was an improvement in the number of micturitions per 24 h period in the solifenacin succinate group compared to placebo at a mean dose of 6 mg/day (p = 0.01). In the open label phase, the mean number of urinary incontinence episodes per 24 h period decreased (p = 0.03), as did the number of nocturia episodes per 24 h period (p = 0.01). Adverse events included constipation and xerostomia, which resolved after treatment was discontinued.

CONCLUSIONS

In this pilot trial, solifenacin succinate treatment led to an improvement in urinary incontinence, despite persistence in other OAB symptoms.

Treatment of cerebellar ataxia

SUMMARY 

Symptoms of cerebellar degeneration include ataxia or wide-based gait, visual and speech dysfunction, dysmetria, and dyscoordination. The etiology of cerebellar degeneration is vast and often complex, and requires neuroimaging, lab assessments, and a thorough family history to delineate its cause. There is currently no accepted treatment of hereditary cerebellar degeneration, although several pharmaceutical agents have shown potential promise.

Autologous stem cell transplant with gene therapy for Friedreich ataxia

We advance the overarching hypothesis that stem cell therapy is a potent treatment for Friedreich's ataxia (FRDA). Here, we discuss the feasibility of autologous transplantation in FRDA, highlighting the need for the successful isolation of the FRDA patient's bone marrow-derived mesenchymal stem cells, followed by characterization that these cells maintain the GAA repeat expansion and the reduced FXN mRNA expression, both hallmark features of FRDA. Next, we discuss the need for assessment of the proliferative capability and pluripotency of FRDA patient's bone marrow-derived mesenchymal stem cells. In particular, we view the need for characterizing the in vitro differentiation of bone marrow-derived mesenchymal stem cells into the two cell types primarily affected in FRDA, peripheral neurons and cardiomyocytes. Finally, we discuss the need to test the application of bone marrow-derived mesenchymal stem cells as potent autologous donor cells for FRDA. The demonstration of the functional correction of the mutated gene in these cells will be a critical endpoint of determining the potential of stem cell therapy in FRDA. We envision a gene-based cell transplant strategy as a likely therapeutic approach for FRDA, involving stable insertion of functional human bacterial artificial chromosomes or BACs containing the intact FXN gene into stem cells, thereafter leading to the expression of frataxin protein in differentiated neurons/cardiomyocytes.

Nonmotor symptoms of Parkinson’s disease

Nonmotor symptoms occur commonly in Parkinson's disease (PD) patients and are frequently under-recognized and undertreated. Symptoms include sleep abnormalities, fatigue, autonomic disturbances, mood disorders and cognitive dysfunction. Early recognition and treatment of nonmotor symptoms in PD is critical to providing optimal management. A new screening questionnaire and the revised Unified PD Rating Scale should assist healthcare providers to better identify and evaluate these symptoms. This article reviews the identification and treatment of nonmotor symptoms in PD.

Clinical characteristics of patients with spinocerebellar ataxias 1, 2, 3 and 6 in the US; a prospective observational study

Background

All spinocerebellar ataxias (SCAs) are rare diseases. SCA1, 2, 3 and 6 are the four most common SCAs, all caused by expanded polyglutamine-coding CAG repeats. Their pathomechanisms are becoming increasingly clear and well-designed clinical trials will be needed.

Methods

To characterize the clinical manifestations of spinocerebellar ataxia (SCA) 1, 2, 3 and 6 and their natural histories in the United States (US), we conducted a prospective multicenter study utilized a protocol identical to the European consortium study, using the Scale for the Assessment and Rating of Ataxia (SARA) score as the primary outcome, with follow-ups every 6 months up to 2 years.

Results

We enrolled 345 patients (60 SCA1, 75 SCA2, 138 SCA3 and 72 SCA6) at 12 US centers. SCA6 patients had a significantly later onset, and SCA2 patients showed greater upper-body ataxia than patients with the remaining SCAs. The annual increase of SARA score was greater in SCA1 patients (mean ± SE: 1.61 ± 0.41) than in SCA2 (0.71 ± 0.31), SCA3 (0.65 ± 0.24) and SCA6 (0.87 ± 0.28) patients (p = 0.049). The functional stage also worsened faster in SCA1 than in SCA2, 3 and 6 (p = 0.002).

Conclusions

The proportions of different SCA patients in US differ from those in the European consortium study, but as in the European patients, SCA1 progress faster than those with SCA2, 3 and 6. Later onset in SCA6 and greater upper body ataxia in SCA2 were noted. We conclude that progression rates of these SCAs were comparable between US and Europe cohorts, suggesting the feasibility of international collaborative clinical studies.

Diagnosis and treatment of essential tremor

SUMMARY Essential tremor (ET) is one of the most prevalent movement disorders in the world, affecting millions of people. Medications that are commonly used to treat ET include antiepileptic or antihypertensive medications. Primidone and propranolol are considered effective, first-line agents for treating ET, while atenolol, alprazolam and topiramate are considered second-line agents. Gabapentin appears to improve ET when used as a monotherapy, although not as an adjunct therapy. Alternatives to pharmacologic treatment for refractory ET include botulinum toxin A injections, deep-brain stimulation of the ventral intermediate nucleus of the thalamus and thalamotomy. Future developments in the treatment of ET will depend on valid animal models and a greater understanding of its pathophysiology.

Randomized trial of cognitive speed of processing training in Parkinson disease

OBJECTIVE

To examine the efficacy of cognitive speed of processing training (SOPT) among individuals with Parkinson disease (PD). Moderators of SOPT were also examined.

METHODS

Eighty-seven adults, 40 years of age or older, with a diagnosis of idiopathic PD in Hoehn & Yahr stages 1-3 and on a stable medication regimen were randomized to either 20 hours of self-administered SOPT (using InSight software) or a no-contact control condition. Participants were assessed at baseline and after 3 months of training (or an equivalent delay). The primary outcome measure was useful field of view test (UFOV) performance, and secondary outcomes included cognitive self-perceptions and depressive symptoms.

RESULTS

Results indicated that participants randomized to SOPT experienced significantly greater improvements on UFOV performance relative to controls, Wilks λ = 0.938, F 1,72 = 4.79, p = 0.032, partial η(2) = 0.062. Findings indicated no significant effect of training on secondary outcomes, Wilks λ = 0.987, F2,70 < 1, p = 0.637, partial η(2) = 0.013.

CONCLUSIONS

Patients with mild to moderate stage PD can self-administer SOPT and improve their cognitive speed of processing, as indexed by UFOV (a robust predictor of driving performance in aging and PD). Further research should establish if persons with PD experience longitudinal benefits of such training and if improvements translate to benefits in functional activities such as driving.

CLASSIFICATION OF EVIDENCE

This study provides Class III evidence that SOPT improves UFOV performance among persons in the mild to moderate stages of PD.

Neuronal nicotinic receptor agonists improve gait and balance in olivocerebellar ataxia

Clinical studies have reported that the nicotinic receptor agonist varenicline improves balance and coordination in patients with several types of ataxia, but confirmation in an animal model has not been demonstrated. This study investigated whether varenicline and nicotine could attenuate the ataxia induced in rats following destruction of the olivocerebellar pathway by the neurotoxin 3-acetylpyridine (3-AP). The administration of 3-AP (70 mg/kg followed by 300 mg niacinamide/kg; i.p.) led to an 85% loss of inferior olivary neurons within one week without evidence of recovery, and was accompanied by a 72% decrease in rotorod activity, a 3-fold increase in the time to traverse a stationary beam, a 19% decrease in velocity and 31% decrease in distance moved in the open field, and alterations in gait parameters, with a 19% increase in hindpaw stride width. The daily administration of nicotine (0.33 mg free base/kg) for one week improved rotorod performance by 50% and normalized the increased hindpaw stride width, effects that were prevented by the daily preadministration of the nicotinic antagonist mecamylamine (0.8 mg free base/kg). Varenicline (1 and 3 mg free base/kg daily) also improved rotorod performance by approximately 50% following one week of administration, and although it did not alter the time to traverse the beam, it did improve the ability to maintain balance on the beam. Neither varenicline nor nicotine, at doses that improved balance, affected impaired locomotor activity in the open field. Results provide evidence that nicotinic agonists are of benefit for alleviating some of the behavioral deficits in olivocerebellar ataxia and warrant further studies to elucidate the specific mechanism(s) involved.

Methodological issues in clinical drug development for essential tremor

Essential tremor (ET) is one of the most common tremor disorders in the world. Despite this, only two medications have received Level A recommendations from the American Academy of Neurology to treat it (primidone and propranolol). Even though these medications provide relief to a large group of ET patients, up to 50% of patients are non-responders. Additional medications to treat ET are needed. This review discusses some of the methodological issues that should be addressed for quality clinical drug development in ET.

Clinical trials of add-on medications in Parkinson's disease: Efficacy versus usefulness

Clinical trials designed to evaluate the efficacy of new anti-parkinsonian agents often employ an 'add-on' protocol in which patients with motor fluctuations on levodopa are randomized to receive active medication or placebo. Levodopa doses may not be increased, but can be decreased in response to dopaminergic side-effects such as increasing dyskinesia or hallucinations. Although these trials can delineate efficacy, additional studies are necessary to evaluate the usefulness of these medications in the clinical setting. The most important questions to be answered by such studies are: (1) Is the benefit derived from addon medication greater than that which could be brought about by further levodopa titration alone?, and (2) Can 'off' time be decreased and motor function improved without a proportionate increase in unwanted dyskinesia? The short-term symptomatic usefulness of an add-on medication can be evaluated by comparing the effects of the addition of active medication plus levodopa titration to further levodopa titration alone. We discuss the limitations of current add-on protocols as well as protocols which may help address the issue of clinical usefulness.

Cardiac dysfunction exacerbated by endocrinopathies in Friedreich ataxia: a case series

Friedreich ataxia is a neurodegenerative disease characterized by gait abnormalities, cardiomyopathy, and diabetes. Congestive heart failure was recently reported as the most frequent cause of Friedreich ataxia mortality. Cardiac dysfunction is suspected to result from a frataxin deficiency that leads to oxidative damage in cardiac tissues and possible metabolic syndrome characteristics. In this report, we describe 2 patient cases whose cardiac function worsened dramatically in the presence of underlying endocrinopathies. We report on one Friedreich ataxia teenager with previously undiagnosed diabetes that resulted in diabetic ketoacidosis and rapid progression to severe left ventricular dysfunction. We also describe a Friedreich ataxia teenager whose underlying Graves disease led to rapid worsening of known cardiomyopathy. Cardiac management and treatment for the endocrinopathies returned cardiac function to baseline. We conclude that screening for and awareness of underlying endocrinopathies in Friedreich ataxia may provide novel therapeutic targets for preventing Friedreich ataxia-associated cardiac dysfunction.

Placebo-controlled trial of lubiprostone for constipation associated with Parkinson disease

OBJECTIVE

To evaluate the efficacy and tolerability of lubiprostone (Amitiza) for constipation in Parkinson disease (PD) in a double-blind, randomized, controlled study.

METHODS

Patients with PD and clinically meaningful constipation (constipation rating scale score > 10 [range: 0-28]) were recruited from 2 academic movement disorder centers to participate in the study. After enrollment, patients were initially followed for 2 weeks and then were randomly assigned 1:1 to lubiprostone, and the dose was titrated up to 48 μg/day. They returned 4 weeks later for a final assessment. Data included stool diaries and global impressions (co-primary endpoints), demographics, Unified Parkinson's Disease Rating Scale scores, constipation scale scores, visual analog scale (VAS) scores, a stool diary, and adverse events.

RESULTS

Fifty-four subjects (39 male, mean age 67.0 ± 10.1 years, and mean duration of PD 8.3 ± 5.4 years) were randomly assigned to lubiprostone or placebo. One patient in the drug group discontinued the study because of logistics, and one patient in the placebo group discontinued the study because of lack of efficacy. A marked or very marked clinical global improvement was reported by 16 of 25 (64.0%) subjects receiving drug vs 5 of 27 (18.5%) subjects receiving placebo (p = 0.001). The constipation rating scale (p < 0.05), VAS (p = 0.001), and stools per day in the diary (p < 0.001) all improved with drug compared with placebo. Adverse events with drug were mild, most commonly intermittent loose stools.

CONCLUSION

In this randomized controlled trial, lubiprostone seemed to be well tolerated and effective for the short-term treatment of constipation in PD.

A randomized trial of varenicline (Chantix) for the treatment of spinocerebellar ataxia type 3

OBJECTIVE

The objective of this double-blind, placebo-controlled, randomized study was to evaluate the efficacy of varenicline (Chantix), a partial agonist at α4β2 neuronal nicotinic acetylcholine receptors used for smoking cessation, in patients with spinocerebellar ataxia (SCA) 3.

METHODS

Patients with genetically confirmed SCA3 were randomly assigned to receive either varenicline (4 weeks for titration and 4 weeks at a dose of 1 mg twice daily) or placebo. Outcome measures included changes in the Scale for the Rating and Assessment of Ataxia (SARA) scores at endpoint (8 weeks) compared with baseline, a timed 25-foot walk and 9-hole peg test, measurements of mood and anxiety, and adverse events.

RESULTS

Twenty patients with SCA3 (mean age = 51 ± 10.98 years; mean disease duration = 14 ± 9.82 years; mean SARA score = 16.13 ± 4.67) were enrolled in the study, and data on 18 patients were analyzed in period I. The most common side effect associated with varenicline was nausea. Improvements were noted in the SARA subsections for gait (p = 0.04), stance (p = 0.03), rapid alternating movements (p = 0.003), and timed 25-foot walk (p = 0.05) and Beck Depression Inventory scores (p = 0.03) in patients taking varenicline compared with those taking placebo at endpoint, with a trend toward improvement in the SARA total score (p = 0.06) in the varenicline group.

CONCLUSIONS

In this controlled study, varenicline significantly improved axial symptoms and rapid alternating movements in patients with SCA3 as measured by SARA subscores and was fairly well tolerated.

CLASSIFICATION OF EVIDENCE

This study provides Class II evidence that varenicline improved the axial functions of gait, stance, and timed 25-foot walk but did not improve appendicular function, except for rapid alternating movements, in adult patients with genetically confirmed SCA3.

Depressive symptoms in Parkinson disease: degree of association and rate of agreement of clinician-based and self-report measures

Depression in Parkinson disease (PD) is associated with faster disease progression, lower activities of daily living, and more severe cognitive impairment. Even mild symptoms of depression may impact outcomes in patients with PD. Nevertheless, a low rate of agreement has been reported between patient and clinician ratings of depression, suggesting that clinicians may underestimate depression in patients with PD. However, to accurately compare the rates of agreement, comparable estimates are needed so that patient and clinician ratings have similar meaning (eg, mild, moderate, severe, etc). The purpose of this study was to examine this question by investigating the degree of association and rate of agreement of levels of symptom severity among self-report and clinician ratings using established cutoffs that correspond to more comparable estimates of these levels for both patient and clinician. Our findings suggest that patient's self-report of depressive symptoms was significantly correlated with clinician-based report irrespective of the stage of disease. Moreover, patients demonstrated a 72% rate of agreement with clinicians in classifying symptoms as asymptomatic, mildly symptomatic, or fully symptomatic, a rate significantly higher than the rate of 35% previously reported. This difference in rate of agreement may be accounted for using varying criteria for severity levels across the studies. Findings suggest that clinician and patient reports show a high rate of agreement across a range of depressive symptoms and that self-report measures may provide a relatively efficient means of detecting depressive symptoms especially if patients are disinclined to initiate their report.

Evidence-based guideline update: treatment of essential tremor: report of the Quality Standards subcommittee of the American Academy of Neurology

BACKGROUND

This evidence-based guideline is an update of the 2005 American Academy of Neurology practice parameter on the treatment of essential tremor (ET).

METHODS

A literature review using MEDLINE, EMBASE, Science Citation Index, and CINAHL was performed to identify clinical trials in patients with ET published between 2004 and April 2010.

RESULTS AND RECOMMENDATIONS

Conclusions and recommendations for the use of propranolol, primidone (Level A, established as effective); alprazolam, atenolol, gabapentin (monotherapy), sotalol, topiramate (Level B, probably effective); nadolol, nimodipine, clonazepam, botulinum toxin A, deep brain stimulation, thalamotomy (Level C, possibly effective); and gamma knife thalamotomy (Level U, insufficient evidence) are unchanged from the previous guideline. Changes to conclusions and recommendations from the previous guideline include the following: 1) levetiracetam and 3,4-diaminopyridine probably do not reduce limb tremor in ET and should not be considered (Level B); 2) flunarizine possibly has no effect in treating limb tremor in ET and may not be considered (Level C); and 3) there is insufficient evidence to support or refute the use of pregabalin, zonisamide, or clozapine as treatment for ET (Level U).

Delayed clinical improvement after deep brain stimulation-related subdural hematoma. Report of 4 cases

OBJECT

The purpose of this paper is to present 4 cases that illustrate the management and outcome of subdural hematoma (SDH) following deep brain stimulation (DBS) lead implantation.

METHODS

The authors identified 4 cases of SDH following DBS lead implantation from a pool of 500 consecutive lead implantations (incidence 0.08%) performed at the University of Florida. Cases were characterized by chart review, serial Unified Parkinson's Disease Rating Scale evaluations, and changes on serial postoperative imaging studies.

RESULTS

Two of the 4 patients with DBS-related SDH were clinically symptomatic. In the other 2 cases the SDH was incidentally discovered on routine postoperative lead localization imaging studies. None of the patients required craniotomy for evacuation of the SDH in the acute phase. Three of the 4 cases were managed with bur hole drainage in the chronic phase, and one was successfully managed nonoperatively. In all 4 cases, thresholds for stimulationinduced side effects were lower during initial postoperative programming than during intraoperative macrostimulation. Expected clinical improvement from DBS was achieved without lead revision in all 4 cases, but only after a significant delay.

CONCLUSIONS

Subdural hematoma is a rare and potentially avoidable complication of DBS that does not typically mandate acute hematoma evacuation or hardware revision and does not preclude an excellent outcome from DBS therapy. The clinical picture and apparent lead position tend to improve with time, and it may be wise to delay repositioning of an ineffective DBS lead following a hemorrhage until the DBS lead and surrounding brain tissue have settled into their final position and the insulted brain has had sufficient time to recover.

Patients' and caregivers' experiences of the impact of Parkinson's disease on health status

BACKGROUND: Parkinson's disease (PD) is a neurodegenerative disease that significantly affects patients' quality of life. The myriad complexities of the disease, including its nonmotor manifestations, are beginning to be more fully appreciated, particularly in regard to the emotional and social effects of PD. Considering that both motor and nonmotor manifestations of PD significantly influence the health outcomes and conditions of patients, and their health-related quality of life (HRQOL), we collected qualitative data from patients with PD, as well as caregivers of persons with PD having cognitive impairment, to assess their perceptions of the impact of PD on HRQOL. METHODS: We conducted eight focus groups and five one-on-one interviews in English and in Spanish between March 2007 and February 2008. Three of the focus groups were conducted with a total of 15 caregivers; the remaining focus groups and all interviews were conducted with 48 PD patients. Study participants were asked about the challenges that PD patients may experience, particularly pertaining to physical functioning, the impact of PD on their emotional status, and social functioning. RESULTS: Based on analysis of the transcripts, we identified seven overarching domains or themes that reflect patients' perspectives on living with PD, ie, physical functioning, social and role functioning, emotional impact, fears and uncertainty about the future, stigma and other feelings about PD, coping mechanisms, and benefits of having PD. CONCLUSION: We underscore the salient aspects regarding the physical effects of PD along with its nonphysical ramifications, offering perspectives into the experience of PD and suggestions on how PD patients and their caregivers may cope with the disease.

Drug-induced hyperkinetic movement disorders by nonneuroleptic agents

Hyperkinetic movement disorders are characterized by excess movement, and include chorea, akathesia, asterixis, dystonia, tremor, myoclonus, and tics. A wide variety of pharmacologic agents may induce or exacerbate these disorders. Neuroleptic-induced tardive dyskinesia and levodopa-induced hyperkinesia are the most common causes of medication-induced chorea. However, several nonneuroleptic agents, including antidepressants and antiepileptic medications, may also worsen hyperkinetic movement disorders. Over-the-counter medications, such as analgesics and antiheartburn medications, have also occasionally been implicated as causing hyperkinetic movement disorders. Most information regarding drug-induced hyperkinetic disorders comes from case reports and anecdotes, rather than controlled clinical trials. Further research with larger controlled trials needs to verify many of these findings.

Overview of essential tremor

Essential tremor (ET) is one of the most common movement disorders in the world. Despite this, only one medication (propranolol) is approved by the Food and Drug Administration (FDA) to treat it. Fortunately, recent studies have identified some additional medications as treatment of ET. Surgical procedures, such as deep brain stimulation of the ventral intermediate nucleus of the thalamus, offer treatment for refractory tremor. The epidemiology, pathogenesis, and medical and surgical treatment of ET will be discussed in this paper.