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It accepted in most quarters that fibromyalgia is associated with reduced rapid-eye-movement (REM) sleep and increased non-REM sleep. One of the goals of those who treat fibromyalgia is to try to reverse this trend, and hopefully allow for more refreshing sleep, and thus less fibromyalgia pain. However, research has shown that it is best this REM sleep be healthy REM sleep. Otherwise, it may be a case of beware of what you wish for.
REM sleep behavior disorder can most easily be described as dreams accompanied by excessive movement. And a recent series of cases published in the journal "Neurology" concludes that such a sleep disorder may be a harbinger of neurodegenerative conditions such as Parkinson's disease that manifest several decades later.
Among 27 patients with Parkinson's disease, multiple system atrophy or dementia with Lewy bodies, the average time between the onset of REM sleep behavior disorder and the onset of the respective neurodegenerative condition was 25 years; but one case was found to have 50 years between symptom manifestation of the two disorders.
This long period of time between REM sleep behavior disorder and an illness such as Parkinson's is important, as therapies might possibly be developed that could be implemented well before the cognitive and motor deterioration becomes evident-ideally halting these disabling hallmarks of disease. Possible therapies include pharmacologic, surgical and (stem) cell-based and gene therapies.
The mean age of the onset of the sleep disorder was 49, and that of the onset of neurologic symptoms was 72. 89% of the patients studied were male. The REM sleep behavior disorder presented itself as dreams in which patients were defending themselves or running away from an aggressive human or animal. Movements during these dreams included punching, shouting, rising out of bed, and flailing arm movements. The subsequent neurologic condition was evenly divided between motor symptoms (the tremor of Parkinson's) and cognitive impairment.
Data from the latest follow-up revealed that 63% of study subjects had developed either Parkinson's disease dementia or dementia with Lewy bodies. The authors of this paper did note that in previous studies not all patients with REM sleep behavior disorder eventually developed diseases such as Parkinson's. Still, the long latencies between the flailing arms during the dreams of those with REM sleep behavior disorder and the neurodegenerative illnesses discussed above do beg the question as to whether everyone with this sleep behavior disorder would later develop a neurodegenerative illness if they lived long enough.
I think I will stay up late tonight.
