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.