Sleep Duration in the United States: A Cross-sectional Population-based Study

Abstract

Sleep duration is associated with cardiovascular disease and diabetes risk factors, depression, automobile and workplace accidents, and prospective mortality. Little is known, however, about sleep patterns in the US population. The 2004-2007 National Health Interview Survey-Sample Adult Files provide nationally representative data for 110,441 noninstitutionalized US adults aged 18 years or older, and multinomial logistic regression examines whether variables in 5 domains-demographic, family structure, socioeconomic, health behavior, and health status-are associated with long or short sleep duration. Being older, non-Hispanic black, or a current or former smoker; having low levels of education, income, or few income sources; consuming few or numerous drinks in a week; or reporting cardiovascular disease, diabetes, depression, underweight, or activity limitations is associated with increased odds of both long and short sleep duration. Other variables are associated with shorter (e.g., living with young children, being unmarried, working long hours, more frequent binge drinking) or longer (e.g., being younger, Mexican American, pregnant, or having low levels of physical activity) sleep hours. The authors identify numerous risk factors for long and short sleep; many of those variables are potential confounders of the relation between sleep hours and other health outcomes.

Factors associated with short and long sleep

“…Sleep duration was determined from the question, "About how many hours in each 24 h day do you usually spend sleeping (including at night and naps)?" and was coded as < 6 h, 6 h (≥ 6 h, < 7 h), 7 h (≥ 7 h, < 8 h), 8 h (≥ 8 h, < 9 h) and ≥ 9 h to be consistent with previous studies (Ferrie et al, 2007, Shankar et al, 2008and Krueger and Friedman, 2009 Body size (i.e. underweight, lean, overweight, obese) was determined on the basis of body mass index using recommended cut-off levels (World Health Organization, 2000).…”

“…These findings are concerning because short sleep is increasingly common and is currently reported by approximately 30% of US adults (Kripke et al, 1979, Kripke et al, 2002, Nunes et al, 2008and Krueger and Friedman, 2009). Long sleep (≥ 9 h sleep a night) has also been associated with increased morbidity and mortality in adult populations (Tamakoshi and Ohno, 2004, Ferrie et al, 2007, Hublin et al, 2007and Shankar et al, 2008.…”

“…Therefore, interventions targeting sleep duration may have implications for the prevention and management of chronic disease. Krueger and Friedman (2009) recently examined sleep patterns in a nationally representative survey of 110,441 US adults. Short and long sleep were reported by 28.3% and 8.5% of respondents respectively, and were associated with low education levels, low income, alcohol consumption, depression and chronic health conditions such as cardiovascular disease and diabetes.…”

“…Bartlett et al (2008) recently found that 18.5% of Australian adults aged 18-64 years (n = 3300) reported sleep durations below 6.5 h a night, but potential predictors of short and long sleep were not examined. The purpose of the present study was to apply an analytic approach similar to Krueger and Friedman (2009) to investigate the sleep patterns of Australian adults and identify possible socio-demographic, behavioral and health determinants of short and long sleep.…”

Effects of Inadequate Sleep on Blood Pressure and Endothelial Inflammation in Women: Findings From the American Heart Association Go Red for Women Strategically Focused Research Network

“…Inadequate sleep is common, with 28% of the US adult population reporting ≤6 hours of sleep per night and with that, a corresponding 24% increased risk of cardiovascular disease 1, 2, 3, 4, 5, 6, 7. Women adopt such behavior in disproportionately greater numbers in part because of lifelong demands on them as caregivers, first to their children and later to ailing and/or elderly family members 8, 9.…”