Sleep and aging: examining the effect of psychological symptoms and risk of sleep-disordered breathing.

Controversy exists as to whether self-reported sleep quality declines with age, despite changes in sleep being accepted as part of normal aging. This study sought to investigate age-related differences in self-reported sleep quality, after controlling for conditions that are common with age, such as psychological symptoms and increased risk of sleep-disordered breathing (SDB). The Pittsburgh Sleep Quality Index (PSQI) was administered to a sample of 582 community adults (aged 18-89 years), and the association between age and 3 factors of the PSQI (sleep efficiency, perceived sleep quality, and daily disturbance), and global scores, was examined controlling for depression, anxiety, stress, gender, and SDB risk. Results indicate that (a) before controlling for covariates, there was no significant relation between age and all indexes of self-reported sleep quality, with the exception of sleep efficiency. However, once depression, gender, and SDB risk were controlled for, a significant, yet small, relation was revealed between older age and poorer global sleep quality; (b) there was no association between age and perceived sleep quality or daily disturbances before or after controlling for relevant covariates; and (c) depression, gender, and SDB risk were significant predictors of poorer sleep quality across the indexes but, in general, did not have a marked impact on the relation between age and sleep quality. In conclusion, results suggest that sleep problems are common across the lifespan, and that there were modest age-related differences in self-reported sleep quality, which were not due to depressed mood, gender, or risk of SDB.