Consistency of respiratory measurements from night to night during the sleep of elderly men.

Fourteen healthy elderly men had polysomnography performed on two consecutive nights to assess the consistency of sleep and breathing from night to night. The reported first-night effect was seen on electroencephalographic sleep, leading to lighter or fitful sleep on the first night. Mean values for apneas, hypopneas, and oxygen desaturations did not change from night 1 to night 2. Five of 14 subjects would have changed classification from night to night if a cutoff of five apneas and hypopneas per hour were used to define normality. Because this numerical cutoff may not be valid in the elderly, the clinical significance of such a changing classification is not clear.

Relationships between sleep and retirement-nonretirement status.

Two-week sleep diaries and four consecutive nights of laboratory recordings were obtained from a sample of forty (17 males, 23 females) fifty- to seventy-year-old people. Participants were drawn from the same work pool and were divided into age matched retired-employed subsamples. Twenty-nine measures of EEG sleep structure were analyzed using two-way (sex-by-employment status) ANOVA. There were no significant main effects associated with employment status. Sleep pattern measures derived from two-week diaries were analyzed using two-way ANOVA. The two significant work status main effects indicated that retirees spend more time sleeping on weekday nights than employed peers, and that employed participants had later bed times on weekend nights than retirees. The one significant interaction indicated that employed males slept for significantly less time on weekend nights than retired males. There were indications that retirement status decreased the frequency of napping, which may result from their more extended night time sleep period.