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Subjective Sleep Disturbance in Chronic Back Pain

Although disturbed sleep is thought to be common in patients with chronic low back pain, little data systematically address this issue. We administered a self-report inventory of sleep performance to an unselected sample of chronic low back pain patients (n= 51) attending a general orthopedic clinic. Approximately 50% (n= 26) of the group experienced poor sleep. Self-reported dissatisfaction with sleep was more strongly associated with more depressed mood and with shorter pain chronicity than with medical evidence of orthopedic disease. Patients with high pain intensity reported significantly less sleep time, more delayed sleep onset, and more nighttime awakenings than did patients with low pain intensity. Overnight polysomnography in a subsample of seven depressed and nondepressed patients with poor sleep revealed abnormalities in a proportion of these subjects, including reduced total sleep time, decreased or absent Stage 3 and 4 sleep, shortened time to onset of rapid eye movement sleep, and periodic leg movements in sleep. Sleep complaints appear to be common in back pain patients and may reflect diverse sleep anomalies. The pathophysiology of these disturbances may be related to pain complaint, affective distress, or independent sleep disorders.