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F4‐05‐03: ASSOCIATION OF AD PATHOLOGY AND NON‐RAPID EYE MOVEMENT SLOW WAVE ACTIVITY
Author(s) -
Lucey Brendan P.,
Toedebusch Cristina D.,
McLeland Jennifer S.,
Landsness Eric C.,
McCue Lena,
Xiong Chengjie,
McCullough Austin,
Benzinger Tammie L.S.,
Morris John C.,
Holtzman Dave M.
Publication year - 2018
Publication title -
alzheimer's and dementia
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 6.713
H-Index - 118
eISSN - 1552-5279
pISSN - 1552-5260
DOI - 10.1016/j.jalz.2018.06.2882
Subject(s) - non rapid eye movement sleep , polysomnography , clinical dementia rating , medicine , cognitive decline , neuroscience , dementia , sleep apnea , neocortex , montreal cognitive assessment , psychology , apnea , eye movement , disease
brain, completed 5.860.6 24-hour periods of wrist actigraphy, the Mini-Mental State Examination (MMSE), and the Center for Epidemiological Studies Depression Scale (CES-D). Using functional principal component (fPC) analysis, we identified 10 uncorrelated patterns (fPCs) accounting for 90% of variability in actigraphic RARs. Participants’ fPC scores were included simultaneously in models as primary predictors. Outcomes were volumes of gray matter, white matter, ventricles, inferior temporal gyrus, hippocampus, and parahippocampal gyrus, all normalized to intracranial volume. We adjusted for age, sex, race, education, CES-D and MMSE. Results were rounded to the nearest 30 minutes. Results: Participants were aged 72.9 611.5 years, 56.0% women, and 28.7% racial/ethnic minorities. fPC1 represented the average 24-hour RAR pattern across all subjects, in which activity sharply increased at 6am, peaked at 8:30am, then slowly decreased until 9pm, when it decreased sharply until 6am. Participants with higher fPC1 scores had greater white matter volume (p1⁄40.009) and smaller ventricles (p1⁄40.005). Other patterns were linked to lower brain volumes. For example, higher fPC4 (reflecting higher activity from 4:30-8am and lower activity from 8-12:30pm) and higher fPC8 scores (representing an “ultradian” pattern, with repeated cycles of high-to-low activity within a day) were linked to lower inferior temporal gyrus volume (p<0.008 for both); fPC4 was also linked to lower hippocampal volume (p1⁄40.047). Finally, higher fPC10 scores (representing an ultradian pattern distinct from fPC8) were associated with lower parahippocampal gyrus (p1⁄40.023) and greater ventricular volume (p1⁄40.001). Conclusions: In cognitively normal older adults, atypical RARs are associated with lower brain volumes, including in regions affected early in AD. Further research is needed on RARs as modifiable contributors to, or markers and predictors of preclinical neurodegeneration.