Sleep disturbances in Alzheimer's disease may be related to the severity of dementia and possibly to the associated periodic limb movements in sleep ( PLMS) or sleep-related respiratory dysrhythmias. The presenting complaints include insomnia, inversion of sleep rhythm, and in some cases, excessive daytime sleepiness. 'Sundowning' is a major problem, characterized by episodes of confusion accompanied by partial or complete inversion of sleep rhythm with increased wakefulness at night and excessive daytime sleepiness. Mechanisms of sleep disturbances in Alzheimer's disease include degeneration of the neurones of the suprachiasmatic nuclei. Other factors include associated depression, PLMS, general medical disorders, medication effects, and environmental factors.
Sleep difficulties are noted in 70 to 90 per cent of patients with Parkinson's disease, (23,) and include difficulty in initiating and maintaining sleep causing sleep fragmentation, with frequent arousals and excessive daytime sleepiness. Sleep problems in Parkinson's disease arise from a combination of factors: an inability to turn over at night or on awakening in the middle of the night, leg cramps and jerks, dystonic spasm of the limbs or face, back pain, excessive nocturia, difficulty in getting out of bed unaided, and re-emergence of tremor and rigidity in sleep. Sleep disruption is more common in advanced than in early Parkinson's disease.
Antiparkinsonian medications may induce either peak-dose dyskinesias (mainly choreiform) or end-of-dose dyskinesia (mostly dystonic), causing disruption and fragmentation of sleep. Other abnormal movements which may occur after prolonged L-dopa therapy are myoclonus, akathisia, and PLMS which may cause sleep-initiating problems. Vivid or frightening dreams (nightmares) and sometimes psychosis can occur after long-standing dopaminergic treatment, causing sleep maintenance problems and excessive daytime sleepiness.
Sleep disruption in Parkinson's disease can also be caused by depression, dementia, sleep apnoea, restless legs syndrome, REM behaviour disorder (see Chapter.. 4,14,4), other parasomnias (sleep walking, sleep talking), and circadian rhythm disturbances. Sleep-related respiratory dysrhythmias (e.g. obstructive, central, or mixed apnoeas or hypopnoeas) may be more common in Parkinson's disease patients than in age-matched elderly controls.(2,3)
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How Would You Love To Finally Get A Decent Night's Sleep? Do you toss and turn all night long without getting much of a wink of sleep? Are you tired of counting sheep for hours without falling asleep? Wouldn't you love to be able to fall asleep simply, easily and naturally, without pills, potions or harmful medicine?