Sleep Disorders in Atypical Parkinsonisms

Abstract

Atypical parkinsonism includes dementia with Lewy bodies (DLB), multiple system atrophy (MSA), and progressive supranuclear palsy (PSP). In DLB, insomnia, circadian rhythm changes, frequent daytime napping, confusional awakenings, and REM sleep behavior disorder (RBD) are frequent. Severity of dementia is linked to abnormal sleep architecture even in the forms of ambiguous sleep and status dissociatus. In DLB, RBD may be the presenting symptom and is considered a red flag of the disease. About 70 % of the MSA patients report sleep problems such as insufficient and fragmented sleep, hypersomnia, RBD, and stridor. RBD and stridor are considered red flags of MSA and may be their initial manifestation. Death during sleep is not infrequent in MSA subjects with untreated stridor. Nasal continuous positive airway pressure and tracheostomy abolish stridor in MSA. PSP patients complain of insomnia and have reduced and abnormal sleep architecture on polysomnography. RBD occurs in PSP but is much less frequent than in DLB and MSA. The cause of sleep disorders in atypical parkinsonisms are multifactorial and they include the degenerative process itself; parkinsonism leading to immobility; coexistent disturbances such as depression, dementia, and anxiety; and the effect of some medications. Treatment should be individualized.