The relationship of sleep complaints to mood, fatigue, disability,
and lifestyle was examined in 69 chronic fatigue syndrome
(CFS) patients without psychiatric disorder, 58 CFS patients
with psychiatric disorder, 38 psychiatric out-patients with
chronic depressive disorders, and 45 healthy controls. The
groups were matched for age and gender.
There were few differences between the prevalence or nature
of sleep complaints of CFS patients with or without current
DSM-IIIR depression, anxiety or somatization disorder. CFS
patients reported significantly more naps and waking by pain,
a similar prevalence of difficulties in maintaining sleep, and
significantly less difficulty getting off to sleep compared to
depressed patients. Sleep continuity complaints preceded
fatigue in only 20% of CFS patients, but there was a strong
association between relapse and sleep disturbance. Certain
types of sleep disorder were associated with increased
disability or fatigue in CFS patients.
Disrupted sleep appears to complicate the course of CFS. For
the most part, sleep complaints are either attributable to the
lifestyle of CFS patients or seem inherent to the underlying
condition of CFS. They are generally unrelated to depression
or anxiety in CFS.