Affiliations: [a]
Hinda and Arthur Marcus Institute for Aging Research, Hebrew Senior Life, Roslindale, MA, USA
| [b]
Harvard Medical School, Harvard University, Boston, MA, USA
| [c] Aging, Mobility, and Cognitive Health Laboratory, University of British Columbia, Vancouver, BC, Canada
| [d]
Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, BC, Canada
| [e]
Centre for Hip Health and Mobility, Vancouver Coastal Health Research Institute, Vancouver, BC, Canada
Correspondence:
[*]
Correspondence to: Dr. Chun Liang Hsu, PhD, Hinda and Arthur Marcus Institute for Aging Research, 1200 Centre Street, Boston, MA 02131, USA. E-mail: chunlianghsu@hsl.harvard.edu.
Abstract: Background:Poor sleep quality is common among older individuals with mild cognitive impairment (MCI) and may be a consequence of functional alterations in the brain; yet few studies have investigated the underlying neural correlates of actigraphy-measured sleep quality in this cohort. Objective:The objective of this study was to examine the relationship between brain networks and sleep quality measured by actigraphy. Methods:In this cross-sectional analysis, sleep efficiency and sleep fragmentation were estimated using Motionwatch8 (MW8) over a period of 14 days in 36 community-dwelling older adults with possible MCI aged 65–85 years. All 36 participants underwent resting-state functional magnetic resonance imaging (fMRI) scanning. Independent associations between network connectivity and MW8 measures of sleep quality were determined using general linear modeling via FSL. Networks examined included the somatosensory network (SMN), frontoparietal network (FPN), and default mode network (DMN). Results:Across the 36 participants (mean age 71.8 years; SD = 5.2 years), mean Montreal Cognitive Assessment score was 22.5 (SD = 2.7) and Mini-Mental State Examination score was 28.3 (SD = 1.5). Mean sleep efficiency and fragmentation index was 80.1% (SD = 10.0) and 31.8 (SD = 10.4) respectively. Higher sleep fragmentation was significantly correlated with increased connectivity between the SMN and insula, the SMN and posterior cingulate, as well as FPN and primary motor area (FDR-corrected, p < 0.004). Conclusion:Functional connectivity between brain regions involved in attentional and somatosensory processes may be associated with disrupted sleep in older adults with MCI.
