Résumé
Sleep disturbances, such as insomnia, rapid eye movement sleep disorders and excessive daytime sleepiness, are symptoms that are commonly associated with movement disorders. This article discusses the prevalence and underlying mechanisms of sleep disturbances in patients with Parkinson's disease or atypical parkinsonism, and proposes therapeutic approaches that could benefit both the patient and their sleeping partner.
Altered sleep and vigilance are among the most frequent symptoms, besides parkinsonism, in movement disorders. As many as 60% of patients with Parkinson's disease (PD) experience insomnia, 15–59% show rapid eye movement (REM) sleep behavior disorders (RBDs), and 30% show excessive daytime sleepiness. Insomnia is a distressing difficulty to maintain sleep, which is exacerbated by motor disability, painful dystonia, restless legs, dysuria, anxiety and depressed mood. Improving night-time motor control by overnight treatment with levodopa, transdermal or long-acting dopamine agonists, or bilateral subthalamus stimulation, can improve sleep continuity. RBDs are violent, enacted dreams that expose the patient or their sleeping partner to night-time injuries. A striking improvement of parkinsonism is observed during these behaviors in PD. RBDs are thought to be caused by lesions in the REM sleep atonia system, and can, in association with other early markers of neurodegenerative diseases, such as olfactory, cognitive and autonomic disturbances, precede parkinsonism by several years. Daytime sleepiness, often with a narcolepsy-like phenotype, is a common occurrence in PD, owing to lesions in the arousal systems of the brain. The use of dopamine agonists increases the risk of sleep attacks, especially when driving, suggesting a drug–disease interaction.
Key Points
As many as 60% of patients with Parkinson's disease (PD) experience insomnia, 15–60% exhibit rapid eye movement (REM) sleep behavior disorders (RBDs), and 30% show excessive daytime sleepiness
Insomnia in PD is a distressing symptom that can be improved by better control of night-time disability, restless legs syndrome and dystonia
RBDs are characterized by violent enacted dreams; this condition might act as a harbinger of parkinsonism several years before disease onset
A striking disappearance of parkinsonism is observed during RBD in PD, suggesting a restoration of motor control during sleep
In patients with PD, daytime sleepiness can culminate in sleep attacks that can impair driving ability; a narcolepsy-like phenotype is observed in one-third of patients
Sleepiness is caused by a disease–drug interaction, with specific lesions in arousal (noradrenergic, serotonergic and orexinergic) systems; dopamine agonists expose patients to a twofold increase in the frequency of sleep attacks
Stridor is the main nocturnal complication in multiple system atrophy, and patients with this condition can benefit from continuous positive airway pressure