Sleep disorders in patients with Parkinson's disease: epidemiology and management

Patients with Parkinson's disease can experience a number of sleep disorders, including insomnia, parasomnias and daytime somnolence [specifically, excessive daytime sleepiness (EDS) and sleep attacks]. Insomnia is a frequent and important complaint of patients with the disease. Both the pathology of Parkinson's disease and dopaminergic drugs may contribute to the much higher than expected frequency of sleep fragmentation and disrupted sleep among these patients. In addition, coexisting depression seems to be a major and frequent risk factor for insomnia in Parkinson's disease. After recognising a sleep problem, the first step in management is to examine and diagnose the type of insomnia and possible medical or psychological factors that may disturb nocturnal sleep. The next step is to give the patient appropriate advice on sleep hygiene. Increasing the dosage of dopaminergic drug treatment will often increase sleep disruption and should be avoided unless the patient's sleep is primarily disturbed by the motor manifestations of parkinsonism during the night. Depression should be looked for and if appropriate be treated in any patients with insomnia. If it becomes necessary to treat the patient with an hypnosedative agent, it is important to use a drug with a short half-life and that manifests as few adverse effects as possible the next morning. Up-to-date guidelines for the use of hypnosedatives should be followed. Patients with Parkinson's disease experience a wide range of parasomnias. The majority of behaviours may be related to rapid eye movement (REM) sleep behaviour disorder (RBD) or to a spectrum of symptoms ranging from vivid dreaming to psychosis. RBD is effectively treated with clonazepam. In addition, the atypical antipsychotics have given physicians new and better treatment options for psychotic symptoms in individuals with Parkinson's disease. EDS is common in Parkinson's disease, while sleep attacks seem to be rare manifestations of the disease or its treatment. Significant EDS is found in 15% of patients with Parkinson's disease compared with in 1% of healthy elderly people. Sleep attacks are observed in patients treated with all dopaminergic medications but have recently been brought to prominence because of their association with the newer dopamine agonists ropinirole and pramipexole. Patients with Parkinson's disease should be informed about the possibility of developing sleep problems during the day when prescribed new drugs. Appropriate actions with regard to driving must be taken if significant and persistent daytime somnolence or sleep attacks appear.