Original ArticleThe association of sleep duration and quality with all-cause and cause-specific mortality in the Women’s Health Initiative
Introduction
Modern society has had a profound influence on our sleep habits. Since the 1960s, the average reported nightly sleep duration in the U.S. has decreased from more than 8 h–6.5 h per night, with 20–30% of middle-aged Americans reporting an average nightly sleep duration of less than 6 h [1]. Poor sleep quality and quantity have been associated with a range of adverse health outcomes, including diabetes, cardiovascular disease, and cancer as well as elevated total and cause-specific mortality [1], [2], [3], [4], [5], [6], [7], [8], [9], [10], [11], [12], [13], [14], [15].
Over the past 40 years, numerous prospective studies have shown a U-shaped association between sleep duration and mortality, with an increased risk of all-cause and cause-specific mortality among both short and long sleepers, compared with those sleeping 7–8 h per night [2], [3], [4], [5], [6], [7], [8], [9], [10], [11], [12], [13], [14], [15]. However, the association is difficult to interpret owing to limitations of these studies, including: variation in categories of sleep duration by study; inconsistencies in the findings by sex and age; the availability of only a single assessment of sleep duration (at baseline) in all but a few studies [6], [7]; the failure of some studies to take potential confounders or effect modifiers (eg, poor pre-existing health) into account; and the failure of most studies to examine sleep quality [6], [12], [15].
Therefore, we used data from the Women's Health Initiative(WHI) cohort to examine sleep duration, insomnia, and use of sleep medications in relation to total and cause-specific mortality. The availability of measurements of sleep-related factors at multiple time points as well as information on medical history at enrollment and on conditions reported during follow-up enabled analysis of the independent and joint effects sleep duration and sleep quality on mortality.
Section snippets
Dataset
The Women's Health Initiative is a large, multicenter study designed to improve our understanding of the determinants of major chronic diseases in postmenopausal women. It was originally composed of a clinical trial component (CT, n = 68,132) and an observational study component (OS, n = 93,676) [16]. The CT component included four randomized controlled intervention studies: hormone therapy (two trials), low-fat dietary modification, and calcium + vitamin D supplementation. Women between the
Results
Women with the lowest and highest number of hours of sleep per night had higher BMI and systolic blood pressure, higher levels of depression, use of sleep aids, fair-to-poor health, and a history of diabetes, CVD, or cancer (Table 1). Women at the extremes of the distribution of sleep hours also had lower levels of physical activity and were less likely to white, to be college-graduates, or to report ever use of hormone therapy. Women with insomnia had higher BMI, more pack-years of smoking,
Discussion
In the present study, both short and long sleep duration measured at the baseline visit were associated with increased risk of total mortality, CVD mortality, and other mortality, but not with cancer mortality. Insomnia reported at baseline showed a weak inverse association with total and CVD mortality, whereas use of sleep aids was associated with increased risk of total mortality, CVD mortality, and other mortality. The pattern of associations was generally similar in sensitivity analyses
Acknowledgments
Additional Contributions: We thank the Women's Health Initiative investigators, staff, and the trial participants for their outstanding dedication and commitment.
Women's Health Initiative Investigators.
Program Office: (National Heart, Lung, and Blood Institute, Bethesda, MD) Jacques Roscoe, Shari Ludlum, Dale Burden, Joan McGowan, Leslie Ford, and Nancy Geller.
Clinical Coordinating Center: (Fred Hutchinson Cancer Research Center, Seattle, WA) Garnet Anderson, Ross Prentice, Andrea LaCroix, and
References (41)
- et al.
Mortality associated with short sleep duration: the evidence, the possible mechanisms, and the future
Sleep Med Rev
(2010) - et al.
Mortality related to actigraphic long and short sleep
Sleep Med
(2011) - et al.
Insufficient and excessive amounts of sleep increase the risk of premature death from cardiovascular and other diseases: the Multiethnic Cohort Study
Prev Med
(2013) - et al.
Investigation of the relationship between sleep duration, all-cause mortality, and preexisting disease
Sleep Med
(2013) - et al.
Association of sleep duration with the morbidity and mortality of coronary artery disease: a meta-analysis of prospective studies
Heart Lung Circulat
(2015) - et al.
Self-reported sleep duration and coronary heart disease mortality: a large cohort study of 400,000 Taiwanese adults
Int J Cardiol
(2016) - et al.
Sleep duration, sleep quality and cardiovascular disease mortality among the elderly: a population-based cohort study
Prev Med
(2009) - et al.
Implementation of the Women's health initiative study design
Ann Epidemiol
(2003) - et al.
The Women's Health Initiative Observational Study: baseline characteristics of participants and reliability of baseline measures
Ann Epidemiol
(2003) - et al.
Longitudinal changes in insomnia status and incidence of physical, emotional, or mixed impairment in postmenopausal women participating in the Women's Health Initiative (WHI) study
Sleep Med
(2015)
Outcomes ascertainment and adjudication methods in the Women's Health Initiative
Ann Epidemiol
Potential biochemical pathways for the relationship between sleep duration and mortality
Sleep Med
An epidemiological perspective on one tale of a two-tailed hypothesis
Sleep Med Rev
Sleep disturbance, sleep duration, and inflammation: a systematic review and meta-analysis of cohort studies and experimental sleep deprivation
Biol Psych
The impact of sleep disorders on glucose metabolism: endocrine and molecular mechanisms
Diabetol Metabol Syndr
Sleep quality and risk of diabetes and coronary artery disease among young men
Acta Diabetol
Short and long sleep and sleeping pills. Is increased mortality associated?
Arch Gen Psychiatry
Morality risk associated with sleeping patterns among adults
Sleep
Mortality associated with sleep duration and insomnia
Arch Gen Psychiatry
Sleep and mortality: a population-based 22-year follow-up study
Sleep
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2021, Sleep MedicineCitation Excerpt :In regard to the risk of CVD, there is evidence that insomnia symptoms are associated with increased risk for CVD morbidity and mortality [10,13,14]. In post-menopausal women, a population commonly affected by sleep disturbances, multiple studies have reported on the association of poor sleep quality with increased CVD incidence [15–22]. Specifically, women who have fewer hours of nightly sleep and higher scores on the Women's Health Initiative Insomnia Rating Scale (WHIIRS), a moderately sensitive measure of insomnia, experience higher incidence of coronary heart disease (CHD) [19].