Psychometric evaluation of the Stanford Sleepiness Scale.

Two assumptions underlying the Stanford Sleepiness Scale (SSS) were evaluated: that the descriptors defining each level of the scale are equivalent ways of characterizing a particular level of sleepiness; and that sleepiness, thus measured, is an unidimensional construct. Twenty-four True/False items were derived from the descriptors at each level of the SSS. This revised scale was administered to 340 undergraduates in a questionnaire which also included: the SSS; four visual analogue scales; items identifying the subject's age, sex, and circadian type; and the time of administration. Analyses of the responses indicated that endorsement of items on the revised scale was not consistent with the SSS level endorsed, indicating that the descriptors at each scale level are not equivalent. A principal components analysis revealed two components, tentatively identified as activation and sleepiness, accounting, respectively, for 24.2 and 20.6% of the variance. It was concluded that sleepiness is not an unidimensional construct. Further studies are necessary to elucidate the nature of its components.

The effects of cyclobenzaprine on sleep physiology and symptoms in patients with fibromyalgia.

A double blind, placebo controlled, crossover design study examined overnight sleep physiology, pain, fatigue, and mood symptoms in 12 patients with fibromyalgia treated with cyclobenzaprine. Nine patients completed the study. Patients receiving cyclobenzaprine showed a decrease in evening fatigue (F = 4.7, p less than 0.05) and an increase in total sleep time (F = 4.4, p less than 0.05). Pain, including tender point count and dolorimetry, mood ratings, and alpha non-REM EEG sleep anomaly were unchanged by cyclobenzaprine.

Sleep and symptoms in fibrositis syndrome after a febrile illness.

Sleep physiology and symptoms of 9 patients with fibrositis syndrome secondary to a febrile illness were compared to 9 patients with fibrositis syndrome who did not attribute their symptoms to a febrile illness and to 10 healthy controls. Both patient groups showed an alpha EEG (7.5 to 11 Hz) nonrapid eye movement sleep anomaly, had similar observed tender points, and self-ratings of musculoskeletal pain. These findings suggest that patients with postfebrile fibrositis have a nonrestorative sleep disorder characteristic of patients with fibrositis syndrome and share similar symptoms with patients who have a "chronic fatigue syndrome."

Sleep and morning pain in primary osteoarthritis.

Sleep physiology, pain and mood symptoms of 8 patients with idiopathic osteoarthritis of the hands who complained of morning symptoms were compared to 7 age and sex matched subjects with similar joint pathology, but who did not complain of morning symptoms. The "AM Symptoms" group had sleep related (nocturnal) myoclonus, associated with increased morning peripheral joint tenderness and decreased grip strength, whereas the "No Complaint" group had improved mood in the morning.

Treatment of chronic insomnia by restriction of time in bed.

A treatment of chronic insomnia is described that is based on the recognition that excessive time spent in bed is one of the important factors that perpetuates insomnia. Thirty-five patients, with a mean age of 46 years and a mean history of insomnia of 15.4 years, were treated initially by marked restriction of time available for sleep, followed by an extension of time in bed contingent upon improved sleep efficiency. At the end of the 8-week treatment program, patients reported an increase in total sleep time (p less than 0.05) as well as improvement in sleep latency, total wake time, sleep efficiency, and subjective assessment of their insomnia (all p less than 0.0001). Improvement remained significant for all sleep parameters at a mean of 36 weeks after treatment in 23 subjects participating in a follow-up assessment. Although compliance with the restricted schedule is difficult for some patients, sleep restriction therapy is an effective treatment for common forms of chronic insomnia.

Sleep and posttraumatic rheumatic pain modulation disorder (fibrositis syndrome).

The clinical features and sleep physiology of 11 female patients with "fibrositis syndrome" or rheumatic pain modulation disorder (RPMD) were compared with 11 female postaccident pain (PAP) patients who complained of widespread musculoskeletal pain, fatigue, and nonrestorative sleep following a nonphysically injurious motor vehicle or work-related accident. Both groups had similar musculoskeletal pain, fatigue, sleepiness and an alpha (7.5-11 Hz) EEG non-rapid eye movement (NREM) sleep anomaly. A psychophysiologic arousal mechanism during NREM sleep induced by the emotional stress of the accident may mediate the subsequent nonrestorative sleep, musculoskeletal pain, and fatigue symptoms in the posttraumatic pain disorder.

Periodic movements in sleep and sleep-wake complaint.

Periodic movements during sleep (PMS) are frequent, involuntary movements, usually of the lower extremities, that disrupt sleep. Twelve patients (nine men and three women, mean age 53.9 years) with a complaint of persistent insomnia (DIMS) were compared with 11 patients (eight men and three women, mean age 53.0 years) complaining of excessive daytime sleepiness (DOES). DIMS patients had more PMS (both absolute and relative), a longer delay to sleep onset and to REM onset, more wakefulness after sleep onset, and less total sleep time. Although the fragmentation of physiological sleep was more severe in the DIMS patients, those individuals with DOES reported cognitive intrusions during their sleep. While DOES patients may be regarded as "sleeping through" the brief arousals associated with leg activity during sleep, there appears to be sufficient cognitive awareness of the nocturnal interruption to precipitate a complaint of daytime sleepiness. Insomnia patients, however, appear to experience longer and more frequent awakenings, which are proportional to increased fragmentation of sleep.