Sleep disruption-related diseases

Further disruption of REM sleep is related to the presence of hallucinations and REM sleep behavior disorder in Parkinson s patients. A decrease in REM sleep has been associated with nocturnal hallucinations (125), and REM intrusion during daytime hallucinations has been reported (126). More than one third of Parkinson s patients also suffer from REM sleep behavior disorder (RBD) (127,128) or REM sleep without atonia (128). In these patients, there is also a significant reduction in total sleep time. In many cases RBD is diagnosed several years prior to the onset of Parkinson s disease (129), although a link between disease severity and duration and the presence of RBD has also been reported (128). RBD is most often treated with the administration of clonazepam (104,129). Patients with comorbid dementia and depression also experience a high level of sleep disturbance, associated with nocturnal vocalizations and hallucinations (130). One side effect of many antidepressant medications, however, is insomnia and sleep disturbance (131). 

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