L-DOPA-induced excessive daytime sleepiness in PD: a placebo-controlled case with MSLT assessment

Management of Sleep Disturbances in Parkinson's Disease

Parkinson's disease (PD) is defined by its motor symptoms rigidity, tremor, and akinesia. However, non-motor symptoms, particularly autonomic disorders and sleep disturbances, occur frequently in PD causing equivalent or even greater discomfort than motor symptoms effectively decreasing quality of life in patients and caregivers. Most common sleep disturbances in PD are insomnia, sleep disordered breathing, excessive daytime sleepiness, REM sleep behavior disorder, and sleep-related movement disorders such as restless legs syndrome. Despite their high prevalence, therapeutic options in the in- and outpatient setting are limited, partly due to lack of scientific evidence. The importance of sleep disturbances in neurodegenerative diseases has been further emphasized by recent evidence indicating a bidirectional relationship between neurodegeneration and sleep. A more profound insight into the underlying pathophysiological mechanisms intertwining sleep and neurodegeneration might lead to unique and individually tailored disease modifying or even neuroprotective therapeutic options in the long run. Therefore, current evidence concerning the management of sleep disturbances in PD will be discussed with the aim of providing a substantiated scaffolding for clinical decisions in long-term PD therapy.

Modafinil alleviates levodopa-induced excessive nighttime sleepiness and restores monoaminergic systems in a nocturnal animal model of Parkinson's disease

Treatment with dopaminergic agents result excessive daytime sleepiness (EDS) and some studies have shown the benefit of using modafinil for treating excessive daytime sleepiness of Parkinson's disease (PD) patient. We investigated whether modafinil have ameliorative properties against levodopa induced excessive nighttime sleepiness (ENS) in MPTP-treated murine nocturnal PD model. Our EEG analyses of whole day recordings revealed that modafinil reduce ENS of this nocturnal PD models with levodopa medications. Therefore, we investigated whether, modafinil post-treatment followed by MPTP shows any effect on monoamine contents of brain and found to robustly increased noradrenaline (NA) concentration of MPTP treated mice. Modafinil post-treatment, in neurorestorative context (5 days post-lesion) led to increased striatal dopamine (DA) concentrations of MPTP-treated mice. Here, we first confirmed that modafinil ameliorates levodopa induced excessive sleepiness and restores monoaminergic systems. The arousal and anti-parkinsonian effects displayed by modafinil indicate that in combination with dopaminergic agents, modafinil co-administration may be worthwhile in trying to suppress the excessive daytime sleepiness and progressive dopaminergic neuron loss in PD.

Genetics and Treatment Response in Parkinson's Disease: An Update on Pharmacogenetic Studies

Parkinson's disease (PD) is a complex neurodegenerative disorder characterized by a progressive loss of dopamine neurons of the central nervous system. The disease determines a significant disability due to a combination of motor symptoms such as bradykinesia, rigidity and rest tremor and non-motor symptoms such as sleep disorders, hallucinations, psychosis and compulsive behaviors. The current therapies consist in combination of drugs acting to control only the symptoms of the illness by the replacement of the dopamine lost. Although patients generally receive benefits from this symptomatic pharmacological management, they also show great variability in drug response in terms of both efficacy and adverse effects. Pharmacogenetic studies highlighted that genetic factors play a relevant influence in this drug response variability. In this review, we tried to give an overview of the recent progresses in the pharmacogenetics of PD, reporting the major genetic factors identified as involved in the response to drugs and highlighting the potential use of some of these genomic variants in the clinical practice. Many genes have been investigated and several associations have been reported especially with adverse drug reactions. However, only polymorphisms in few genes, including DRD2, COMT and SLC6A3, have been confirmed as associated in different populations and in large cohorts. The identification of genomic biomarkers involved in drug response variability represents an important step in PD treatment, opening the prospective of more personalized therapies in order to identify, for each person, the better therapy in terms of efficacy and toxicity and to improve the PD patients' quality of life.

Sleep Dysfunction in Parkinson's Disease

The spectrum of sleep problems in Parkinson's disease (PD) is broad. These symptoms are recognized as being clinically relevant by the PD patients and may seriously affect their quality of life. Some studies reveal the occurrence of sleep disorders in more than half of the PD patients. The etiology is multifactorial and it mainly involves the degeneration of the sleep-regulating structures. Sleep disorders in PD can be classified into: disturbances of sleep and disturbances of wakefulness. Generic and specific scales were designed to help the screening and evaluation of sleep dysfunction. Further assessment can be done using sleep recording techniques, like actigraphy or polysomnography. All types of sleep disturbances may be encountered in PD: insomnia, excessive daytime sleepiness, rapid eye movement sleep behavior disorders, and restless legs syndrome. This chapter will focus on reviewing the main characteristics, pathophysiology, assessment, and management of the most frequent sleep disturbances encountered in PD.

Recommendations of the Sleep Study Group of the Italian Dementia Research Association (SINDem) on clinical assessment and management of sleep disorders in individuals with mild cognitive impairment and dementia: a clinical review

Clinical assessment and management of sleep disturbances in patients with mild cognitive impairment and dementia has important clinical and social implications. Poor sleep results in an increased risk of morbidities and mortality in demented patients and is a source of stress for caregivers. Sleep disturbances show high prevalence in mild cognitive impairment and dementia patients and they are often associated one to another in the same patient. A careful clinical evaluation of sleep disorders should be performed routinely in the clinical setting of individuals with cognitive decline. The Sleep Study Group of the Italian Dementia Research Association (SINDem) reviewed evidence from original research articles, meta-analyses and systematic reviews published up to December 2013. The evidence was classified in quality levels (I, II, III) and strength of recommendations (A, B, C, D, E). Where there was a lack of evidence, but clear consensus, good practice points were provided. These recommendations may not be appropriate for all circumstances and should therefore be adopted only after a patient's individual characteristics have been carefully evaluated.

Parkinson’s disease management strategies

Parkinson's disease (PD) treatment strategies should consider each patient individually. Drug therapy is the mainstay of treatment. An average 62-year-old male first diagnosed with PD will likely live for 20 years and treatment should be geared for long-term control of symptoms and quality of life. Of the currently available drugs, none are neurotoxic to the human substantia nigra and none are neuroprotective. As PD is a progressive disorder, all drugs have adverse effects and reduced efficacy with time. PD patients need regular follow-ups to make necessary medication adjustments. There is no perfect treatment. The authors have discussed their treatment methods and the reasoning behind it. Depending on the patient's age, the predominant symptoms and quality of life, treatment is individualized. In an average patient the least potent drugs, such as anticholinergics or amantadine, are administered first adding a dopamine agonist later on. Levodopa (LD) remains the most useful drug for PD and is reserved for later stages of disease. The objective is to keep the patient at Hoehn and Yahr Stage 2.0 or lower level of disability (bilateral findings with preserved postural reflexes) during off-stage and to avoid adverse effects. There is no long-term difference between standard preparations and control release formulations of LD/carbidopa or LD/benserazide. In older subjects, the first choice is LD. In patients who cannot be managed medically, surgical treatment is an option in selected patients (nondemented, <70 years old, previous good LD response). The surgical treatment of choice is currently subthalamic nucleus deep-brain stimulation. Physiotherapy, occupational therapy and speech therapy are valuable in advanced PD cases.

Switch from selegiline to rasagiline is beneficial in patients with Parkinson's disease

The objective of this study is to demonstrate that application of rasagiline instead of selegiline with concomitant determination of L-amphetamine and L-methamphetamine in plasma is safe and well tolerated and influences sleep, mood, and motor behavior in patients with Parkinson's disease on a stable drug therapy. 30 patients, who took 7.5 mg selegiline daily for at least 3 months, were switched to 1 mg rasagiline. Then they were followed over an interval of 4 months. The remaining drug therapy remained stable. This changeover was safe and well tolerated. L-Amphetamine and L-methamphetamine only appeared during selegiline treatment. Motor behavior, motor complications, mood and sleep improved during rasagiline administration. Amphetamine-like derivatives of selegiline could contribute to sleep disturbances, which may be involved in worsening of mood. Motor behavior and motor complications probably became better due to the additional glutamate receptor antagonizing properties of rasagiline in this open label study.

Antiparkinsonian drug-induced sleepiness: a double-blind placebo-controlled study of L-dopa, bromocriptine and pramipexole in healthy subjects

AIMS

To assess the sleepiness induced by pramipexole, a D2/D3-dopamine receptor agonist commonly used in Parkinson's disease and restless legs syndrome, without the problem of the confounding factors related to the disease.

METHODS

Placebo, bromocriptine (2.5 mg), L-dopa (100 mg) and pramipexole (0.5 mg) were administered in a single oral dose on four separate days, with at least a 2-week wash-out period in a randomized cross-over design. Induced somnolence was assessed using Multiple Sleep Latency Test (MSLT) and subjective scaling of vigilance. Twelve male subjects (26.3 +/- 5.5 years old) without anxiety, mood, sleep or sedation disorders were enrolled.

RESULTS

Pramipexole significantly reduced mean sleep latency compared with placebo 3 h 30 min [-6.1 min (-9.8, -2.4), P = 0.002] and 5 h 30 min [-5.6 min (-7.7, -3.5), P = 0.003] after administration. In addition, the total duration of sleep during the tests was higher with pramipexole than with placebo [+6.0 min (2.3, 9.7), P < 0.001]. These differences were not observed with L-dopa and bromocriptine in comparison with placebo. The induced sleepiness was not associated with an increase in subjective somnolence scaling, indicating that this adverse event may occur without prior warning.

CONCLUSIONS

These results show that a single oral dose of pramipexole induces sleepiness as assessed by MSLT in healthy young subjects, independent of disease-related sleep dysfunction.

Frequent nocturnal vocalization in pure autonomic failure

Nocturnal vocalization is frequent in Parkinson's disease patients with rapid eye movement (REM) sleep behaviour disorder (RBD). We investigated the frequency of nocturnal vocalization and other sleep problems in patients with pure autonomic failure (PAF) and compared the results with idiopathic Parkinson's disease (IPD) and dementia with Lewy bodies (DLB). We interviewed consecutive patient-caregiver pairs with PAF (n = 13), IPD (n = 200) and DLB (n = 19), and ischaemic stroke patients (controls, n = 43). Nocturnal vocalization was similarly frequent in PAF, IPD and DLB. Other dream enactments and vivid dreams also were more frequent in PAF, IPD and DLB compared with controls. Excessive night-time awakenings and daytime sleepiness were frequent in IPD but rare in PAF and controls. Clinical manifestation of sleep disturbances, at least of RBD-like symptoms including nocturnal vocalization and other dream enactments, may occur in PAF, as in IPD and DLB.

Sleep-wake cycle and effects of cabergoline monotherapy in de novo Parkinson's disease patients. An ambulatory polysomnographic study

OBJECTIVE

To investigate the sleep-wake cycle and the effects of cabergoline monotherapy in a homogenous group of de novo Parkinson's Disease (PD) patients without confounding comorbid factors.

DESIGN AND PARTICIPANTS

Twelve de novo patients affected by idiopathic PD underwent two ambulatory polysomnographic (APSG)monitoring sessions. The first was performed at baseline, and the second recording one-month after stable treatment with cabergoline monotherapy. Subjective daytime sleepiness was evaluated by means of the Epworth Sleepiness Scale.Data obtained in PD patients at baseline were compared with those obtained in 12 age- and sex-matched healthy subjects.

RESULTS

Diurnal sleep parameters did not show significant differences between controls and PD patients at baseline. In PD patients, no significant changes in diurnal sleep were observed between baseline and cabergoline treatment. Regarding nocturnal sleep, patients at baseline showed a significantly lower sleep efficiency and a significantly higher Wakefulness After Sleep Onset than controls. With respect to baseline, a significant increase in REM latency and a significant reduction in REM sleep were observed during cabergoline treatment.

CONCLUSIONS

In the early stage of PD, the neurodegenerative process does not seem to be directly responsible for daytime somnolence, but it may be directly involved in the alteration of nocturnal sleep. Cabergoline monotherapy does not affect daytime sleep propensity and, despite clinical improvement, it may have negative effects on REM sleep.

Effect of dopaminergic substances on sleep/wakefulness in saline- and MPTP-treated mice

Sleep/wakefulness (S/W) disorders are frequent in Parkinson's disease (PD). The underlying causes have yet to be elucidated but dopaminergic neurodegenerative lesions seem to contribute to appearance of the disorders and anti-Parkinsonian medication is known to accentuate S/W problems. Hence, we reasoned that studying the acute effect of dopaminergic compounds on S/W in an animal model of PD might improve our knowledge of S/W regulation in the context of partial dopaminergic depletion. To this end, we tested the effect of levodopa (l-dopa), pergolide (a mixed D(2)/D(1) agonist) and lisuride (a D(2) agonist) on S/W recordings in MPTP-treated mice, in comparison with controls. Our results showed that dopaminergic compounds modify S/W amounts in both control and MPTP mice. Wakefulness amounts are greater in MPTP mice after l-dopa (50 mg kg(-1)) and lisuride (1 mg kg(-1)) injections compared with control mice. Moreover, the paradoxical sleep latency was significantly longer in MPTP mice after high-dose l-dopa administration. Our observations suggest that the actions of both l-dopa and lisuride on S/W differ slightly in MPTP mice relative to controls. Hence, MPTP-induced partial DA depletion may modulate the effect of dopaminergic compounds on S/W regulation.

Effect of cabergoline added to levodopa treatment on sleep-wake cycle in idiopathic Parkinson's disease: an open label 24-hour polysomnographic study

Few studies focused on the effects of cabergoline on sleep-wake cycle in PD. Twelve patients affected by PD treated with levodopa as monotherapy underwent two 24-hour ambulatory polysomnographic (A-PSG) sessions twice: in baseline condition (levodopa as monotherapy) and after addition of cabergoline. In each condition, a subjective evaluation of sleep quality and daytime sleepiness was obtained by means of Parkinson's disease Sleep Scale (PDSS) and the Epworth Sleepiness Scale. The statistical analysis of sleep parameters revealed a significant increase of sleep efficiency and slow wave sleep under cabergoline. The PDSS total score showed a significant improvement of overall sleep quality after cabergoline. No significant changes in daytime sleepiness were observed. No patient referred and/or showed sleep attacks before and after addition of cabergoline. We hypothesize that the long-lasting effect of cabergoline may improve the objective quality of nocturnal sleep in PD patients complaining nocturnal motor disability without inducing daytime sleepiness.

Excessive daytime sleepiness in parkinsonism

Excessive daytime sleepiness (EDS) can affect 20-50% of patients with Parkinson's disease (PD), whereas sleep attacks (SA), which are sleep episodes without prodroma, seem infrequent. EDS is associated with more advanced disease, higher doses of levodopa-equivalent, and sometimes the use of dopamine agonists. Patients at risk for SA have higher Epworth sleepiness scores (ESS) (although an important subset of patients under-score on this scale) and a more frequent use of ergot or non-ergot dopamine agonists. Polysomnography is a valuable tool in patients with PD, because sleep apnea may occur in 20% of patients, whereas a specific narcolepsy-like phenotype, identified on multiple-sleep latency tests, occurs in patients with most severe EDS; this suggests a lesion in sleep-wake systems. Removal or replacement of a recently introduced dopamine agonist may offer some relief for EDS. If not, the adjunction of modafinil has a good benefit-risk ratio in patients with PD. EDS (and sometimes the narcolepsy-like phenotype) may also affect patients with atypical parkinsonism, such as dementia with Lewy bodies, multiple-system atrophy, and progressive supranuclear palsy.

Sleep episodes and daytime somnolence as result of individual susceptibility to different dopaminergic drugs in a PD patient: a polysomnographic study

The association between excessive daytime somnolence (EDS) and idiopathic Parkinson's disease (PD) is often reported but still debated. The possible role of antiparkinsonian therapy or primarily of PD on excessive diurnal sleepiness is controversial. We describe the case of a 61-year-old patient affected by PD who experienced sleep episodes (SE) occurring during pramipexole plus L-Dopa therapy. Polysomnographic sleep studies and subjective evaluations of daytime sleepiness (Epworth Sleepiness Scale) were carried out under administration of pramipexole plus L-Dopa, L-Dopa monotherapy and cabergoline plus L-Dopa. The polysomnography revealed two sleep events during pramipexole plus L-Dopa. Moreover, the polysomnographic data showed an increase of both diurnal and nocturnal sleep under pramipexole plus L-Dopa compared with cabergoline plus L-Dopa and L-Dopa as monotherapy. In addition, while Epworth Sleepiness Scale (ESS) Score showed a mild sleepiness under pramipexole (ESS score=11), ESS scores were normal under both L-Dopa and cabergoline plus L-Dopa. Sleep episodes also disappeared under both L-Dopa and cabergoline plus L-Dopa (2- and 12-month follow-up). We hypothesize that an individual susceptibility to specific antiparkinsonian drug may play a significant role in the genesis of sleepiness in our PD patient.