Study Objectives: To determine the association of actigraphic sleep duration and fragmentation with cognition in community-dwelling older women. Methods: We studied 782 women (mean age = 87.4) of varied cognitive status from the Study of Osteoporotic Fractures who completed wrist actigraphy and the Modified Mini-Mental State Examination (3MS), California Verbal Learning Test-II-Short Form, digit span, verbal fluency tests, and the Trailmaking Test, Part B (Trails B). Total sleep time (TST) and wake after sleep onset (WASO) tertiles were our primary predictors. Results: There were few significant associations in adjusted analyses. Compared to women with intermediate TST (mean = 430.1 minutes), those with the longest (508.7 minutes) had significantly poorer performance on the 3MS and phonemic and semantic fluency. Compared to women with the least WASO (31.5 minutes), those in the middle tertile (61.5 minutes) had significantly poorer delayed recall and those in the middle tertile and highest tertile (126.2 minutes) had poorer total recall and semantic fluency. We observed significant adjusted associations of TST with impaired 3MS performance and of WASO with impaired delayed recall, semantic fluency, and digit span. After excluding participants with adjudicated dementia diagnoses or indeterminate cognitive status, some adjusted associations remained but decreased in magnitude, others became nonsignificant, and a new association emerged. Conclusions: In community-dwelling older women, longer objectively measured sleep duration and greater sleep fragmentation are associated with poorer performance and impairment in only a subset of cognitive domains. Some of these associations may be driven by women with dementia in whom disturbed sleep and cognitive performance share an underlying neuropathological basis.
Bibliographical noteFunding Information:
Dr. Spira was supported in part by grants from the National Institute on Aging and has received funding from the William and Ella Owens Medical Research Foundation. He has agreed to serve as a consultant to Awarables, Inc. in support of an NIH grant. Dr. Stone reports that NIH funding has been obtained for this work. Dr. Redline is supported by grants from the NIH NHLBI and has received a subcontract from California Pacific Medical Center for work in this study. She has received research support from Jazz Pharmaceuticals and has received a research grant from ResMed Foundation to support ancillary data collection for an NIH funded clinical trial. She is a member of the Board of Directors for the American Academy of Sleep Medicine. Dr. Redline is the first incumbent of an endowed professorship donated to the Harvard Medical School by Dr. Peter Farrell, the founder and Board Chairman of ResMed, through a charitable remainder trust instrument, with annual support equivalent to the endowment payout provided to the Harvard Medical School during Dr. Farrell’s lifetime by the ResMed Company through an irrevocable gift agreement. Dr. Ensrud received grant support from the NIH (and supporting agencies) as listed above. Dr. Ancoli-Israel is supported by grants from NIH and is a consultant for Ferring Pharmaceuticals Inc., Merck, NeuroVigil, Inc., Purdue Pharma LP. Dr. Cauley received grant support from the NIH (and supporting agencies) as listed above. Dr. Kristine Yaffe has received grants from the National Institute on Aging, National Institute of Mental Health, National Institute of Diabetes and Digestive and Kidney Diseases, Department of Defense, Department of Veterans Affairs, the Alzheimer’s Association, and an anonymous donor. She has served on data safety monitoring boards for Pfizer and Medivation, and received honoraria from Novartis as an advisory board member. She is a member of the boards of the Beeson Program, the National Institute of Mental Health, and the National Heart, Lung and Blood Institute. The sponsors were not involved in the design and conduct of the study; collection, management, analysis, or interpretation of the data; preparation, review, or approval of the manuscript; or decision to submit the manuscript for publication.
This study was supported by National Institutes of Health Grants AG021918, AG026720, AG05394, AG05407, AG08415, AR35582, AR35583, AR35584, R01 AG027576-22, 2 R01 AG005394-22A1, 2 R01 AG027574-22A1, HL40489, K24AG031155, 1K01AG033195 and 1R01AG050507.
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- Older adults