title: Nonreplicability of seasonal rhythm in REM sleep in a subtropical climate.
abstract: The present paper attempts to replicate Askenasy and Goldstein's (1995) findings of seasonality in rapid eye movement (REM) sleep measures in patients recorded in Israel. Analysis of sleep stage data of 706 nonselected male sleep apnea patients failed to find seasonality in REM sleep measures. In contrast, our data revealed stability of REM time with a maximum difference between seasons of 7.0 minutes. Age differences were found in sleep efficiency, true sleep time, and amount and percentage of REM sleep, with patients over 60 having a lower sleep efficiency, shorter true sleep, and REM sleep time than patients under 60. Rapid eye movement latency was also found to differ according to apnea severity, with patients who had > 40 apneas and hypopneas per hour of sleep having a longer latency than those with fewer apneas and hypopneas.
authors.affiliation: Sleep Laboratory, Technion, Israel Institute of Technology, Haifa, Israel.
authors.forename: P
authors.initials: P
authors.lastname: Herer
authors.forename: P
authors.initials: P
authors.lastname: Lavie
mesh_terms: D000328:Adult; D000367:Age Factors; D002980:Climate; D006801:Humans; D008297:Male; D008875:Middle Aged; D010507:Periodicity; D012621:Seasons; D012891:Sleep Apnea Syndromes; D012895:Sleep, REM