Cited by 183Sleep and related disordersSleep and Work-Related FatigueCircadian rhythm and melatonin

Intra-individual daily and yearly variability in actigraphically recorded sleep measures: the CARDIA study

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Knutson, Kristen L., Rathouz, Paul J., Yan, Lijing L., Liu, Kiang, Lauderdale, Diane S.·2007·SLEEP

Abstract

STUDY OBJECTIVES: To describe the day-to-day and year-to-year variation in sleep characteristics among early middle-aged adults. DESIGN: Participants wore an Actiwatch (Mini Mitter, Inc) for 3 days on two occasions approximately 1 year apart. PARTICIPANTS: N = 669 participants aged 38-50 years from the Chicago site of the Coronary Artery Risk Development in Young Adults (CARDIA) cohort study. MEASUREMENTS AND RESULTS: Sleep measures included sleep duration, sleep latency, sleep efficiency, and time in bed. For each sleep parameter, total variance was decomposed into between-subject variance, within-subject variance from day to day, and within-subject variance from year to year. The standard deviation was calculated from the variance. Analysis yielded a within-subject daily standard deviation (SD) of 1.26 hours and a within-subject yearly SD of 0.39 hours for sleep duration. Daily SD was 30.7 minutes and yearly SD was 6.3 minutes for within-subject variability of sleep latency. Daily SD was 8.4% and yearly SD was 2.7% for within-subject variability of sleep efficiency. Finally, daily SD was 1.31 hours and yearly SD was 0.52 hours for within-subject variability of time in bed. CONCLUSIONS: For each of the 4 sleep characteristics, nightly variability was much greater than yearly variability, meaning sleep behavior changes little in one year in this cohort of early middle-aged adults, despite large daily fluctuations. These results have important methodological implications, including that single-day measures of sleep may not accurately reflect habitual behavior.

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  1. [1]Bonnet M. Sleep deprivation. In: Kryger M, Roth T, Dement WC, editors. Principles and practice of sleep medicine. 3rd ed. Philadelphia, PA: WB Saunders Co.; 2000. [Google Scholar]

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Authors
Knutson, K. L., Rathouz, P. J., Yan, L. L., Liu, K., & Lauderdale, D. S.
Affiliations
  • University of Chicago (US)
  • Northwestern University (US)
Corresponding author
Knutson, Kristen L.
Venue
SLEEP
Published
2007-06
Volume
30
Issue
6
Pages
793-796
ISSN
  • 0161-8105 (ISSN-L)
  • 1550-9109
OpenAlex
W2154815992
Cited by
183
References
23
Citations by year
2026: 8 · 2025: 8 · 2024: 9 · 2023: 8 · 2022: 9 · 2021: 11 · 2020: 15 · 2019: 14 · 2018: 11 · 2017: 15 · 2016: 3 · 2015: 9 · 2014: 8 · 2013: 9 · 2012: 6
FWCI
11.13
Type
journal article
Language
en
Open access
Locations
  • SLEEP (publishedVersion)
  • PubMed Central (publishedVersion)
  • PubMed (publishedVersion)
Funders
  • Northwestern University
  • University of Chicago
  • National Institutes of Health (n01hc48049-61-0-1)
  • National Institute on Aging (P01-AG11412., P01AG011412)
  • National Heart, Lung, and Blood Institute (N01-HC-048049, N01-HC-48-049)
Topics
  • Social Sciences › Psychology › Experimental and Cognitive Psychology › Sleep and related disorders
  • Social Sciences › Psychology › Experimental and Cognitive Psychology › Sleep and Work-Related Fatigue
  • Life Sciences › Neuroscience › Endocrine and Autonomic Systems › Circadian rhythm and melatonin
Keywords
sleep variability, sleep duration, sleep latency, sleep efficiency, time in bed, day-to-day variability, interannual variability, actigraphy, middle-aged adults, CARDIA cohort
MeSH terms
Adult, Coronary Disease, Female, Humans, Male, Middle Aged, Severity of Illness Index, Sleep Wake Disorders, Time Factors, Polysomnography

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