Associations between subjective night sweats and sleep study findings

Abstract

Background: In 2 previous studies, patients reporting night sweats were found to be more likely to have other sleep-related symptoms. Sleep apnea is often mentioned as a possible cause of night sweats, but there is little evidence to support this assertion. Methods: Retrospective review of data from 2 sleep laboratories in Oklahoma City, Oklahoma. Analyses included bivariate and multivariate tests of associations between reported night sweats and other sleep-related symptoms, scores on specific sleep inventories, and findings from polysomnography. Results: Patients who reported night sweats were more likely to report daytime fatigue (P = .001); creepy/crawly feelings in their legs (P = .003); kicking during sleep (P = .004); snoring (P < .03); nighttime breathing trouble (P < .0001); awakening in the night with aches and pains (P < .0001); and waking in the morning with a headache (P = .0002) and still tired (P = .002) as compared with those who did not report night sweats. They also had higher mean scores on the Epworth Sleepiness Scale (P < .0001). However, there was no statistically significant association between reported night sweats and sleep onset latency, arousal index, apnea hypopnea index, periodic leg movement index, or total sleep time. Conclusions: Subjective night sweats are associated with a variety of other sleep-related symptoms, but we could find no evidence for an association between subjective night sweats and objective evidence of specific sleep disorders.