by David Douglas

Last Updated: 2009-08-13 14:24:48 -0400 (Reuters Health)

Lower self-reported sleep quality is associated with reduced quality of life, even when polysomnography does not reflect problems, researchers report in the August issue of Sleep.

"The study results," lead investigator Dr. Graciela E. Silva told Reuters Health, "showed that abnormalities in quality of sleep had an important impact on quality of life. Subjective quality of sleep was associated with lower quality of life."

Dr. Silva of Arizona State University, Phoenix and colleagues studied data on 3078 patients with coronary heart disease or respiratory disease who had polysomnography at baseline and approximately 5 years later.

During this period, there was only a modest increase in sleep-disordered breathing. The mean respiratory disturbance index increased from 8.1 to 10.9.

However, said Dr. Silva, "Those subjects who reported having difficulty initiating and maintaining sleep … and those who reported being excessively sleepy during the day had lower quality of life than subjects who did not report having these symptoms."

"Interestingly," she added, "when we measured the subjects’ sleep by polysomnogram—objective sleep—we did not find this association, signaling to the importance of sleep perception."

"Many subjects who suffer from diseases such as coronary heart disease, respiratory diseases, arthritis, and others," she concluded, "will experience poor quality of sleep and therefore adequately treating the subject’s disease with additional therapy to improve their sleep quality will ultimately improve their quality of life."

Sleep 2009;32:1049-1057.