title: Decrease in daytime sleeping is associated with improvement in cognition after hospital discharge in older adults.
abstract: OBJECTIVE
  To examine the relationship between changes in objectively assessed sleep and global cognitive functioning from inpatient postacute rehabilitation to 6-month follow-up.
  
  
  METHODS
  Secondary analysis of two prospective, longitudinal studies.
  
  
  METHODS
  Inpatient rehabilitation units at a Veterans Affairs Medical Center.
  
  
  METHODS
  Older adults (mean age 73.8 ± 9.4) undergoing inpatient rehabilitation (n = 192).
  
  
  METHODS
  All participants completed 7 nights and days of ambulatory sleep monitoring using wrist actigraphy (yielding an estimate of nighttime wakefulness and daytime sleep) and the Mini-Mental State Examination (MMSE) during a postacute inpatient rehabilitation stay and 6 months after discharge. The 5-item Geriatric Depression Scale, Geriatric Pain Measure, and Cumulative Illness Rating Scale for Geriatrics were completed during inpatient rehabilitation.
  
  
  RESULTS
  Growth curve modeling (controlling for baseline age, education, sex, body mass index, depression, pain, and comorbidity burden) revealed that individuals whose amount of daytime sleep decreased from inpatient postacute rehabilitation to 6-month follow-up also experienced improvements in MMSE score (β = -0.01, t(80 = -3.22, P = .002)). Change in nighttime wakefulness was not a significant predictor of change in MMSE score.
  
  
  CONCLUSIONS
  Older adults whose daytime sleeping decreased after hospital discharge also experienced improvements in cognitive functioning at 6 month follow-up. As such, daytime sleep may represent a promising candidate for targeted interventions aimed at promoting cognitive recovery after hospital discharge.
authors.affiliation: Geriatric Research, Education and Clinical Center, Veterans Affairs Greater Los Angeles Healthcare; David Geffen School of Medicine, University of California Los Angeles, USA.
authors.forename: Joseph M
authors.initials: JM
authors.lastname: Dzierzewski
authors.forename: Constance H
authors.initials: CH
authors.lastname: Fung
authors.forename: Stella
authors.initials: S
authors.lastname: Jouldjian
authors.forename: Cathy A
authors.initials: CA
authors.lastname: Alessi
authors.forename: Michael R
authors.initials: MR
authors.lastname: Irwin
authors.forename: Jennifer L
authors.initials: JL
authors.lastname: Martin
mesh_terms: D056044:Actigraphy; D000203:Activities of Daily Living; D000368:Aged; D002908:Chronic Disease / Q000534:rehabilitation; D002940:Circadian Rhythm / Q000502:physiology*; D003071:Cognition / Q000502:physiology*; D003863:Depression / Q000453:epidemiology; D005260:Female; D015577:Geriatric Assessment; D006787:Hospitals, Veterans; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D018670:Monitoring, Ambulatory; D010147:Pain Measurement; D010351:Patient Discharge; D011446:Prospective Studies; D012890:Sleep / Q000502:physiology*; D014481:United States; D014728:Veterans; D014851:Wakefulness
keywords: cognition; inpatient hospitalization; longitudinal change; older adults; sleep
references.citation: Mayo Clin Proc. 2011 Sep;86(9):885-93
references.pmid: 21878601
references.citation: Neurology. 2012 Mar 27;78(13):950-6
references.pmid: 22442434
references.citation: Chest. 2011 Jun;139(6):1514-1527
references.pmid: 21652563
references.citation: Semin Neurol. 2009 Sep;29(4):320-39
references.pmid: 19742409
references.citation: Anesthesiol Clin. 2009 Sep;27(3):485-96, table of contents
references.pmid: 19825488
references.citation: J Am Geriatr Soc. 2000 Dec;48(12):1669-73
references.pmid: 11129760
references.citation: Nat Sci Sleep. 2010 Apr 1;2:47-61
references.pmid: 22323897
references.citation: Sleep Med. 2010 Jan;11(1):56-64
references.pmid: 19962939
references.citation: Arch Gerontol Geriatr. 2011 Mar-Apr;52(2):133-7
references.pmid: 20338647
references.citation: Front Neurol. 2012 Jul 26;3:118
references.pmid: 22855682
references.citation: Psychol Aging. 2007 Mar;22(1):18-27
references.pmid: 17385979
references.citation: J Sleep Res. 2014 Feb;23(1):61-8
references.pmid: 23980920
references.citation: Sleep. 2011 Dec 01;34(12):1715-21
references.pmid: 22131610
references.citation: J Am Geriatr Soc. 2003 May;51(5):694-8
references.pmid: 12752847
references.citation: J Psychiatr Res. 1975 Nov;12(3):189-98
references.pmid: 1202204
references.citation: Brain Behav Immun. 2002 Oct;16(5):503-12
references.pmid: 12401464
references.citation: Sleep Med Rev. 2008 Oct;12(5):391-403
references.pmid: 18502155
references.citation: Exp Gerontol. 2008 Sep;43(9):840-6
references.pmid: 18602982
references.citation: Psychol Aging. 1996 Dec;11(4):621-37
references.pmid: 9000294
references.citation: Trends Neurosci. 2002 Mar;25(3):154-9
references.pmid: 11852148
references.citation: Psychiatry Res. 1992 Mar;41(3):237-48
references.pmid: 1594710
references.citation: JAMA. 2010 Feb 24;303(8):763-70
references.pmid: 20179286
references.citation: Best Pract Res Clin Endocrinol Metab. 2010 Oct;24(5):775-84
references.pmid: 21112025
references.citation: Int J Geriatr Psychiatry. 2002 Jan;17(1):73-7
references.pmid: 11802234
references.citation: Sleep. 1995 Jul;18(6):425-32
references.pmid: 7481413
references.citation: Brain Behav Immun. 2004 May;18(3):214-20
references.pmid: 15116743
references.citation: J Sleep Res. 2009 Mar;18(1):129-35
references.pmid: 19250179
references.citation: J Am Geriatr Soc. 2004 Sep;52(9):1456-62
references.pmid: 15341546
references.citation: J Am Geriatr Soc. 1995 Feb;43(2):130-7
references.pmid: 7836636
references.citation: Dement Geriatr Cogn Disord. 2012;34(3-4):198-205
references.pmid: 23128048
references.citation: J Am Geriatr Soc. 2001 Sep;49(9):1185-9
references.pmid: 11559377
references.citation: Sleep. 2008 Sep;31(9):1291-300
references.pmid: 18788654
references.citation: Neuropsychol Dev Cogn B Aging Neuropsychol Cogn. 2004 Jun;11(2-3):304-24
references.pmid: 16755303
references.citation: J Am Geriatr Soc. 2005 May;53(5):803-10
references.pmid: 15877555