Sleep duration in midlife and later life in relation to cognition - PubMed (original) (raw)

. 2014 Jun;62(6):1073-81.

doi: 10.1111/jgs.12790. Epub 2014 May 1.

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Sleep duration in midlife and later life in relation to cognition

Elizabeth E Devore et al. J Am Geriatr Soc. 2014 Jun.

Abstract

Objectives: To evaluate associations between sleep duration at midlife and later life and change in sleep duration over time and cognition in older women.

Design: Participants reported sleep duration in 1986 and 2000, and a subgroup of older participants began cognitive testing in 1995 to 2001; follow-up testing was conducted three times, at 2-year intervals.

Setting: Prospective Nurses' Health Study cohort.

Participants: Female nurses aged 70 and older free of stroke and depression at the initial cognitive assessment (N = 15,385).

Measurements: Validated, telephone-based cognitive battery to measure cognitive function; four repeated assessments over 6 years were averaged to estimate overall cognition at older ages, and trajectories of cognitive change were evaluated over follow up.

Results: Extreme sleep durations in later life were associated with worse average cognition (P < .001 for the quadratic term for a global score averaging all six cognitive tests). For example, women sleeping 5 h/d or less had worse global cognition than those sleeping 7 h/d, as did women sleeping 9 h/d or more; differences were equivalent to nearly 2 additional years of age. Associations were similar, although slightly attenuated, for sleep duration in midlife. Women whose sleep duration changed by 2 h/d or more over time had worse cognition than women with no change in sleep duration (e.g., for the global score, P < .001 for the quadratic term). Sleep duration was not associated with trajectories of cognitive function over 6 years, which might be attributable to short follow-up for detecting cognitive decline.

Conclusion: Extreme sleep durations at midlife and later life and extreme changes in sleep duration over time appear to be associated with poor cognition in older women.

Keywords: cognition; cohort study; epidemiology; sleep.

© 2014, Copyright the Authors Journal compilation © 2014, The American Geriatrics Society.

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Conflict of interest statement

Conflict of interest: (To be determined by the editorial office based on COI information).

Figures

Figure 1

Figure 1

Means scores representing average cognition in later life across categories of sleep duration in midlife (reported in 1986) a a Estimates are adjusted for age (continuous), education (registered nurse, bachelor’s degree, graduate degree), shift work history (never, 1–9, 10–19, ≥20 years), smoking status (never, past, current), alcohol intake (none 1–14 grams/day, ≥15 grams/day, missing), physical activity (in quintiles of MET-hours/week, missing), body-mass index (<22, 22–24, 25–29, ≥30 kg/m2), history of high blood pressure (yes, no), mental health score on the SF-36 (poor, normal, missing), living alone (yes, no), and tranquilizer use (yes, no). b For each participant, the global score at each cognitive interview is calculated by averaging z-scores for each of the six tests in our cognitive battery. The mean global score representing average cognition in later life is further calculated by averaging global scores across repeated cognitive interviews for each participant. c For each participant, the verbal score at each cognitive interview is calculated by averaging z-scores for each of the four tests of verbal memory in our cognitive battery. The mean verbal score representing average cognition in later life is further calculated by averaging verbal scores across repeated cognitive interviews for each participant. d The mean TICS score representing average cognition in later life is calculated by averaging TICS scores across repeated cognitive interviews for each participant.

Figure 1

Figure 1

Means scores representing average cognition in later life across categories of sleep duration in midlife (reported in 1986) a a Estimates are adjusted for age (continuous), education (registered nurse, bachelor’s degree, graduate degree), shift work history (never, 1–9, 10–19, ≥20 years), smoking status (never, past, current), alcohol intake (none 1–14 grams/day, ≥15 grams/day, missing), physical activity (in quintiles of MET-hours/week, missing), body-mass index (<22, 22–24, 25–29, ≥30 kg/m2), history of high blood pressure (yes, no), mental health score on the SF-36 (poor, normal, missing), living alone (yes, no), and tranquilizer use (yes, no). b For each participant, the global score at each cognitive interview is calculated by averaging z-scores for each of the six tests in our cognitive battery. The mean global score representing average cognition in later life is further calculated by averaging global scores across repeated cognitive interviews for each participant. c For each participant, the verbal score at each cognitive interview is calculated by averaging z-scores for each of the four tests of verbal memory in our cognitive battery. The mean verbal score representing average cognition in later life is further calculated by averaging verbal scores across repeated cognitive interviews for each participant. d The mean TICS score representing average cognition in later life is calculated by averaging TICS scores across repeated cognitive interviews for each participant.

Figure 2

Figure 2

Mean scores representing average cognition in later life across categories of sleep duration in later life (reported in 2000) a a Estimates are adjusted for age (continuous), education (registered nurse, bachelor’s degree, graduate degree), shift work history (never, 1–9, 10–19, ≥20 years), smoking status (never, past, current), alcohol intake (none 1–14 grams/day, ≥15 grams/day, missing), physical activity (in quintiles of MET-hours/week, missing), body-mass index (<22, 22–24, 25–29, ≥30 kg/m2), history of high blood pressure (yes, no), mental health score on the SF-36 (poor, normal, missing), living alone (yes, no), and tranquilizer use (yes, no). b For each participant, the global score at each cognitive interview is calculated by averaging z-scores for each of the six tests in our cognitive battery. The mean global score representing average cognition in later life is further calculated by averaging global scores across repeated cognitive interviews for each participant. c For each participant, the verbal score at each cognitive interview is calculated by averaging z-scores for each of the four tests of verbal memory in our cognitive battery. The mean verbal score representing average cognition in later life is further calculated by averaging verbal scores across repeated cognitive interviews for each participant. d The mean TICS score representing average cognition in later life is calculated by averaging TICS scores across repeated cognitive interviews for each participant.

Figure 2

Figure 2

Mean scores representing average cognition in later life across categories of sleep duration in later life (reported in 2000) a a Estimates are adjusted for age (continuous), education (registered nurse, bachelor’s degree, graduate degree), shift work history (never, 1–9, 10–19, ≥20 years), smoking status (never, past, current), alcohol intake (none 1–14 grams/day, ≥15 grams/day, missing), physical activity (in quintiles of MET-hours/week, missing), body-mass index (<22, 22–24, 25–29, ≥30 kg/m2), history of high blood pressure (yes, no), mental health score on the SF-36 (poor, normal, missing), living alone (yes, no), and tranquilizer use (yes, no). b For each participant, the global score at each cognitive interview is calculated by averaging z-scores for each of the six tests in our cognitive battery. The mean global score representing average cognition in later life is further calculated by averaging global scores across repeated cognitive interviews for each participant. c For each participant, the verbal score at each cognitive interview is calculated by averaging z-scores for each of the four tests of verbal memory in our cognitive battery. The mean verbal score representing average cognition in later life is further calculated by averaging verbal scores across repeated cognitive interviews for each participant. d The mean TICS score representing average cognition in later life is calculated by averaging TICS scores across repeated cognitive interviews for each participant.

Figure 3

Figure 3

Mean scores representing average cognition in later life across categories of change in sleep duration from 1986 to 2000 a a Estimates are adjusted for age (continuous), education (registered nurse, bachelor’s degree, graduate degree), sleep duration in middle age (obtained in 1986) (≤5, 6, 7, 8, ≥9 hours/day), shift work history (never, 1–9, 10–19, ≥20 years), smoking status (never, past, current), alcohol intake (none 1–14 grams/day, ≥15 grams/day, missing), physical activity (in quintiles of MET-hours/week, missing), body-mass index (<22, 22–24, 25–29, ≥30 kg/m2), history of high blood pressure (yes, no), mental health score on the SF-36 (poor, normal, missing), living alone (yes, no), and tranquilizer use (yes, no). b For each participant, the global score at each cognitive interview is calculated by averaging z-scores for each of the six tests in our cognitive battery. The mean global score representing average cognition in later life is further calculated by averaging global scores across repeated cognitive interviews for each participant. c For each participant, the verbal score at each cognitive interview is calculated by averaging z-scores for each of the four tests of verbal memory in our cognitive battery. The mean verbal score representing average cognition in later life is further calculated by averaging verbal scores across repeated cognitive interviews for each participant. d The mean TICS score representing average cognition in later life is calculated by averaging TICS scores across repeated cognitive interviews for each participant.

Figure 3

Figure 3

Mean scores representing average cognition in later life across categories of change in sleep duration from 1986 to 2000 a a Estimates are adjusted for age (continuous), education (registered nurse, bachelor’s degree, graduate degree), sleep duration in middle age (obtained in 1986) (≤5, 6, 7, 8, ≥9 hours/day), shift work history (never, 1–9, 10–19, ≥20 years), smoking status (never, past, current), alcohol intake (none 1–14 grams/day, ≥15 grams/day, missing), physical activity (in quintiles of MET-hours/week, missing), body-mass index (<22, 22–24, 25–29, ≥30 kg/m2), history of high blood pressure (yes, no), mental health score on the SF-36 (poor, normal, missing), living alone (yes, no), and tranquilizer use (yes, no). b For each participant, the global score at each cognitive interview is calculated by averaging z-scores for each of the six tests in our cognitive battery. The mean global score representing average cognition in later life is further calculated by averaging global scores across repeated cognitive interviews for each participant. c For each participant, the verbal score at each cognitive interview is calculated by averaging z-scores for each of the four tests of verbal memory in our cognitive battery. The mean verbal score representing average cognition in later life is further calculated by averaging verbal scores across repeated cognitive interviews for each participant. d The mean TICS score representing average cognition in later life is calculated by averaging TICS scores across repeated cognitive interviews for each participant.

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References

    1. Schoenborn CA, Adams PE. Health behaviors of adults: United States, 2005–2007. Vital Health Stat. 2010;10:1–132. - PubMed
    1. Cappuccio FP, Cooper D, D’Elia L, Strazzullo P, Miller MA. Sleep duration predicts cardiovascular outcomes: a systematic review and meta-analysis of prospective studies. Eur Heart J. 2011;32:1484–1492. - PubMed
    1. Cappuccio FP, D’Elia L, Strazzullo P, Miller MA. Quantity and quality of sleep and incidence of type 2 diabetes: a systematic review and meta-analysis. Diabetes Care. 2010;33:414–420. - PMC - PubMed
    1. Gorelick PB, Scuteri A, Black SE, et al. Vascular contributions to cognitive impairment and dementia: a statement for healthcare professionals from the american heart association/american stroke association. Stroke. 2011;42:2672–2713. - PMC - PubMed
    1. Kang JE, Lim MM, Bateman RJ, et al. Amyloid-beta dynamics are regulated by orexin and the sleep-wake cycle. Science. 2009;326:1005–1007. - PMC - PubMed

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