Sleep Duration and White Matter Quality in Middle-Aged Adults.
STUDY OBJECTIVES
Sleep duration has been associated with risk of dementia and stroke, but few studies have investigated the relationship between sleep duration and brain MRI measures, particularly in middle age.


METHODS
In a prospective cohort of 613 black and white adults (mean age = 45.4 years) enrolled in the Coronary Artery Risk Development in Young Adults (CARDIA) study, participants reported typical sleep duration, dichotomized into moderate sleep duration (> 6 to ≤ 8 h) and short sleep duration (≤ 6 h) at baseline (2005-2006). Five years later, we obtained brain MRI markers of white matter including fractional anisotropy, mean diffusivity, and white matter hyperintensities.


RESULTS
Compared to moderate sleepers, short sleepers had an elevated ratio of white matter hyperintensities to normal tissue in the parietal region (OR = 2.31, 95% CI: 1.47, 3.61) adjusted for age, race/sex, education, hypertension, stroke/TIA, depression, smoking status, and physical activity. White matter diffusivity was also higher, approximately a 0.2 standard deviation difference, in frontal, parietal, and temporal white matter regions, among those reporting shorter sleep duration in (P < 0.05 for all).


CONCLUSIONS
Short sleep duration was associated with worse markers of white matter integrity in midlife. These mid-life differences in white matter may underlie the link between poor sleep and risk of dementia and stroke.
['Yaffe|Kristine|K|', 'Nasrallah|Ilya|I|', 'Hoang|Tina D|TD|', 'Lauderdale|Diane S|DS|', 'Knutson|Kristen L|KL|', 'Carnethon|Mercedes R|MR|', 'Launer|Lenore J|LJ|', 'Lewis|Cora E|CE|', 'Sidney|Stephen|S|']
D000293:Adolescent D000328:Adult D000368:Aged D000369:Aged, 80 and over D000375:Aging D005260:Female D005500:Follow-Up Studies D006801:Humans D008279:Magnetic Resonance Imaging D008297:Male D008875:Middle Aged D010296:Parietal Lobe D011446:Prospective Studies D012890:Sleep D012892:Sleep Deprivation D013997:Time Factors D066127:White Matter D055815:Young Adult
sleep duration white matter hyperintensities white matter integrity midlife