Actigraphy suggests age‐related differences in napping and nocturnal sleep

Abstract

SUMMAR Y The aim of this study was to contrast the time distribution of out-of-bed napping in young and older adults through recordings of wrist activity, and to evaluate the correlates of napping with nocturnal sleep. Seventy-three young adults between 18 and 32 years and 60 older adults between 60 and 75 years of age participated in the study. Subjects were selected for good general health and had few sleep complaints. They wore wrist-activity monitors and kept daily sleep logs for 1 week. Automatic sleep scoring was edited by the authors, supplemented by sleep logs and illumination data as well as activity data. Napping episodes were modestly increased in older adults, but there was no difference in the daily duration of napping. Older adults napped more in the evening (especially within 2 h before bedtime), whereas young adults napped more in the afternoon. The older adults with evening naps (n ¼ 31) showed earlier nocturnal wakeup times and decreased nocturnal sleep duration compared with the older adults without evening naps (n ¼ 29). There was no difference in nocturnal sleep between young adults with afternoon naps (n ¼ 32) and without afternoon naps (n ¼ 41). In determining the effects of napping on nocturnal sleep, timing of napping and age are important. Maintaining alertness during the evening (e.g. by bright light exposure or moderate exercise) would be a possible approach to delay wake-up times in older adults.k e y w o r d s aging, circadian, naps, sleep, wrist activity

Naps and Circadian Rhythms in Postmenopausal Women

“…The study of evening napping is relevant because it has been observed particularly in older adults (7,8) and might be explained in terms of changes of circadian rhythms in aging (9,10). Our previous findings on evening napping and its relation to nocturnal sleep and circadian rhythms (3,6) in older adults are extended here. Future studies should examine more representative samples that will further establish napping characteristics in aging.…”

“…Different patterns of napping between young and older persons have been reported, with the latter taking naps more often in the evening (3). Evening napping, either experimentally induced in the laboratory or observed in home environments, is related to nocturnal sleep and circadian rhythms.…”

Symptom burden of sleep-disordered breathing in mild-to-moderate congestive heart failure patients

“…This good reliability of nap reporting has not always been shown in actigraphy studies [27]. In the recent study by YOON et al [8], older adults (mean age 66.2¡4.9 yrs) were studied with actigraphy. Objectively they napped for 23.3 min?day -1 , which correlates well with subjective and objective data in the current CHF patients.…”

“…Actigraphy is a tool which has been widely used in sleep research to monitor activity over 24-h periods [7,8] in a variety of patient groups [9,10]. Actigraphy has been shown to correlate well with polysomnography [7,11].…”

“…Actigraphy has been shown to correlate well with polysomnography [7,11]. It can be used to define wake epochs during nocturnal sleep, and has also been used to monitor daytime napping in healthy populations [8]. Daytime napping and 24-h activity levels have not previously been documented in CHF patients with or without SDB.…”