REM sleep is associated with white matter integrity in cognitively healthy, older adults

• Published in: PloS one 2020-07, Vol.15 (7), p.e0235395-e0235395
• Main Authors: Altendahl, Marie, Cotter, Devyn L, Staffaroni, Adam M, Wolf, Amy, Mumford, Paige, Cobigo, Yann, Casaletto, Kaitlin, Elahi, Fanny, Ruoff, Leslie, Javed, Samirah, Bettcher, Brianne M, Fox, Emily, You, Michelle, Saloner, Rowan, Neylan, Thomas C, Kramer, Joel H, Walsh, Christine M
• Format: Article
• Language: English
• Subjects: Abnormalities; Adults; Age; Aged; Aged, 80 and over; Aging; Anisotropy; Biology and Life Sciences; Brain; Brain research; Cerebral white matter; Cognition - physiology; Cognitive ability; Corpus callosum; Dementia; Diffusion; Diffusion Magnetic Resonance Imaging; Efficiency; Elderly; Eye movements; Female; Functional anatomy; Health aspects; Humans; Integrity; Male; Medical research; Medicine and Health Sciences; Memory; Mental health; Microstructure; Neuroimaging; Neurology; Neurosciences; Older people; People and Places; Physical Sciences; Physiological aspects; Psychiatry; Rapid eye movement; Regression Analysis; REM sleep; Research and Analysis Methods; Sleep; Sleep (REM); Sleep apnea; Sleep, REM - physiology; Structure-function relationships; Substantia alba; Tensors; White Matter - anatomy & histology; White Matter - physiology
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0235395

There is increasing awareness that self-reported sleep abnormalities are negatively associated with brain structure and function in older adults. Less is known, however, about how objectively measured sleep associates with brain structure. We objectively measured at-home sleep to investigate how sleep architecture and sleep quality related to white matter microstructure in older adults. 43 cognitively normal, older adults underwent diffusion tensor imaging (DTI) and a sleep assessment within a six-month period. Participants completed the PSQI, a subjective measure of sleep quality, and used an at-home sleep recorder (Zeo, Inc.) to measure total sleep time (TST), sleep efficiency (SE), and percent time in light sleep (LS), deep sleep (DS), and REM sleep (RS). Multiple regressions predicted fractional anisotropy (FA) and mean diffusivity (MD) of the corpus callosum as a function of total PSQI score, TST, SE, and percent of time spent in each sleep stage, controlling for age and sex. Greater percent time spent in RS was significantly associated with higher FA (β = 0.41, p = 0.007) and lower MD (β = -0.30, p = 0.03). Total PSQI score, TST, SE, and time spent in LS or DS were not significantly associated with FA or MD (p>0.13). Percent time spent in REM sleep, but not quantity of light and deep sleep or subjective/objective measures of sleep quality, positively predicted white matter microstructure integrity. Our results highlight an important link between REM sleep and brain health that has the potential to improve sleep interventions in the elderly.