Associations between subjective night sweats and sleep study findings.

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.