People with chronic fatigue syndrome (CFS) commonly experience trouble sleeping, and many undergo sleep studies to rule out a primary sleep disorder and explore the specific nature of their sleep disturbance. Such studies have shown reduced sleep efficiency, prolonged sleep initiation (trouble falling asleep), a reduction of deep sleep and alpha-wave intrusion in the sleep cycle.
A recent study in the American Journal of Medicine (February 2007) by Dr. Elke Van Hoof and colleagues compiled information from a large sleep study database of CFS patients, looking for common themes and a relationship to deregulation of the RNase L antiviral pathway—an immune dysfunction common to a subset of CFS patients. RNase L is the key enzyme in the body's antiviral pathway.
Forty-eight patients meeting the 1994 international case definition for CFS underwent extensive medical evaluation, routine lab testing and a structured psychiatric evaluation. Subjects then completed a health complaint checklist and a two-night sleep study. RNase L analysis was also performed on each subject.
Results showed that subjects experienced prolonged trouble initiating sleep, poor sleep efficiency and less slow-wave deep sleep. The alpha-delta wave intrusion, however, appeared to be correlated to anxiety rather than immunologic parameters such as deregulated RNase L. So while this study didn’t find a connection between sleep problems and RNase L, it did validate sleep latency and efficiency problems in CFS patients as well as alpha-delta wave intrusion.