Thursday, July 1, 2010

Pipe Dreams and Sleep in Fibromyalgia: Why some dream of sleep

Pipe Dreams and Sleep in Fibromyalgia: Why some dream of sleep
Published on June 30, 2010
The alpha-EEG sleep <> anomaly was first described by researchers who used the term alpha-delta sleep to characterize a mixture of alpha and delta waves in a small group of psychiatric <> patients described as having generalized feelings of chronic somatic malaise and fatigue. Other researchers found that fibromyalgia <> patients had an excess of alpha-EEG not just in slow wave sleep, but in all NREM (non-rapid-eye-movement) sleep stages. Further, these same researchers discovered that the alpha-EEG sleep anomaly could be reproduced experimentally in healthy individuals by disrupting stage 4 NREM sleep. Alpha-EEG has been correlated to overnight increases in pain and decreases in energy; and the alpha-EEG anomaly may lead to more arousability during sleep, with resultant unrefreshed sleep.
It is well known that fibromyalgia is a chronic pain syndrome that is often associated with sleep disturbances characterized by subjective complaints of non-restorative sleep. Polysomnographic evidence shows abnormalities in the continuity of sleep: There is reduced sleep efficiency with an increased number of awakenings, reduced slow wave sleep, and the alpha-EEG anomaly in NREM sleep. And while fibromyalgia symptoms may relate to a non-restorative sleep disorder <> associated with such alpha-EEG anomalies, because the alpha-EEG anomaly is seen in healthy individuals when their sleep is disrupted, many experts do not wish to call this EEG finding specific for fibromyalgia, particularly because many fibromyalgia patients suffer primary sleep disorders such as sleep apnea <>or restless leg syndrome.
Another group of researchers examined the relation of alpha wave intrusions to not only fibromyalgia, but also major depression and chronic fatigue syndrome patients, all of whom had a main complaint of chronic fatigue. The alpha-EEG anomaly was found in 26% of the patients, major depression in 67%, chronic fatigue syndrome in 50%, and fibromyalgia in 13%. One-third of the patients had a primary sleep disorder (such as sleep apnea, periodic limb movements, or narcolepsy).
Interestingly, the alpha-EEG anomaly was not significantly correlated with fibromyalgia, chronic fatigue syndrome, major depression <>, or a primary sleep disorder.
*It was, however, much more common in patients with chronic fatigue without major depression.* The researchers concluded that primary sleep disorders are common among patients with chronic fatigue; their existence must be suspected, searched for, and treated. *The alpha-EEG anomaly is not a "marker" for fibromyalgia or chronic fatigue syndrome, but it may contribute to the misery of non-depressed patients with these conditions.*
The dream of an objective marker for fibromyalgia remains elusive, with different research teams <> battling over what sleep anomaly is correlated with what diagnosis.
Wake me when the war is over.

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