Exacerbations in chronic obstructive pulmonary disease (COPD) can impair lung function, respiratory symptoms, quality of life, and functional status. But little is known about how these relate to sleep. Aiming to fill this gap, researchers from St. Francis Hospital and Medical Center, Hartford, Connecticut; University of Connecticut; Tufts Medical Center; Boston, Massachusetts; Pulmonary Medicine of Virginia Beach, Virginia; and SSM Health Care, St. Louis, Missouri, assessed a variety of sleep variables in a substudy of an observational longitudinal study.
The substudy followed patients about 6 months. During that time, 15 of 17 patients had 27 symptom-defined exacerbations, and 8 had 9 clinically reported exacerbations. Two exacerbations required hospitalization. One-quarter of the study days were exacerbation days.
The patients’ Stanford Sleepiness Scale score was significantly higher during exacerbations. Patients also had significantly less total sleep time and poorer sleep efficiency. Objective awakenings greatly exceeded subjective awakenings, regardless of exacerbations. None of the 4 variables—sleep time, sleep efficiency, objective awakenings, and subjective awakenings—were strongly associated with daytime sleepiness.
This study did not compare patients with COPD to people without COPD, but the researchers found that total sleep time and sleep efficiency was “substantially worse” than that reported for people with insomnia and for older adults.
The researchers call their findings “hypothesis generating.” Whether the sleep disturbances can be considered clinically meaningful or whether the changes in sleep time and efficiency are causally related to sleepiness, they say, are puzzles for a larger study to address.
Source:
Vanaparthy R, Mota P, Khan R, et al. Chron Respir Dis. 2015;12(4):299–304.
doi: 10.1177/1479972315587517.
