OBJECTIVE: To determine whether disrupted slow wave sleep
(SWS) would evoke musculoskeletal pain, fatigue, and an alpha
electroencephalograph (EEG) sleep pattern. We selectively
deprived 12 healthy, middle aged, sedentary women without
muscle discomfort of SWS for 3 consecutive nights. Effects
were assessed for the following measures: polysomnographic
sleep, musculoskeletal tender point pain threshold, skinfold
tenderness, reactive hyperemia (inflammatory flare response),
somatic symptoms, and mood state.
METHODS: Sleep was recorded
and scored using standard methods. On selective SWS
deprivation (SWSD) nights, when delta waves (indicative of
SWS) were detected on EEG, a computer generated tone (maximum
85 decibels) was delivered until delta waves disappeared.
Musculoskeletal tender points were measured by dolorimetry;
skinfold tenderness was assessed by skin roll procedure; and
reactive hyperemia was assessed with a cotton swab test.
Subjects completed questionnaires on bodily feelings,
symptoms, and mood.
RESULTS: On each SWSD night, SWS was
decreased significantly with minimal alterations in total
sleep time, sleep efficiency, and other sleep stages. Subjects
showed a 24% decrease in musculoskeletal pain threshold after
the third SWSD night. They also reported increased discomfort,
tiredness, fatigue, and reduced vigor. The flare response
(area of vasodilatation) in skin was greater than baseline
after the first, and again, after the third SWSD night.
However, the automated program for SWSD did not evoke an alpha
EEG sleep pattern.
CONCLUSION: Disrupting SWS, without
reducing total sleep or sleep efficiency, for several
consecutive nights is associated with decreased pain
threshold, increased discomfort, fatigue, and the inflammatory
flare response in skin. These results suggest that disrupted
sleep is probably an important factor in the pathophysiology
of symptoms in fibromyalgia.
Lentz MJ, Landis CA, Rothermel J, Shaver JL