To determine the sleep quality and quality of life for individuals with degenerative spinal disease or failed back surgery syndrome.
Cross-sectional survey design utilizing standardized instruments. Data were analyzed with use of hierarchical stepwise multiple regression analyses.
One hundred sixty-seven individuals with degenerative spinal disease or postlaminectomy syndrome who presented to a tertiary care outpatient patient pain center.
The Center for Epidemiological Studies Depression Index measured depressive symptomatology. A modified Pittsburgh Sleep Quality Index (PSQI) measured sleep quality. The arithmetic average of least and usual VAS ratings of pain measured everyday pain. A visual analog scale rating of highest pain during the past 2 weeks measured highest pain. The Epworth Sleepiness Scale measured daytime sleepiness. The Medical Outcome Study-Short Form-Health Survey (SF-36) measured the mental health and general health components of quality of life.
Higher overall sleep quality and lower sleep latency primarily were related to higher ratings of physical functioning and shorter duration of pain. Ratings of the highest pain, but not everyday pain, were independent predictors of overall sleep quality and sleep latency. Daytime sleepiness was associated with younger age and depressed mood. Pain was not associated independently with daytime sleepiness. The quality of life related to mental functioning was associated positively with depressed mood and with the interaction of pain and depressed mood. None of the variables in the model (i.e., pain intensity, sleep quality, depression, and demographic variables) predicted quality of life related to overall general health.
These data suggest that physical functioning, duration of pain, and age may be more important than pain intensity and depressed mood in contributing to decreased overall sleep quality and sleep latency. The contribution of physical functioning was particularly strong and should be included in subsequent studies of sleep, pain, and mood. The SF-36 should be compared to pain-specific quality-of-life measures to further evaluate the usefulness of this instrument with outpatients with chronic nonmalignant pain conditions.