Poor sleep quality and functional decline in older women.
OBJECTIVE
To determine whether objectively measured sleep quality predicts 5-year incident instrumental activity of daily living (IADL) impairment and decline in grip strength and gait speed in older women.


METHODS
Prospective cohort.


METHODS
Participants' homes, Study of Osteoporotic Fractures sites.


METHODS
Eight hundred seventeen women with a mean age of 82.4 at baseline.


METHODS
Participants completed 4.1 ± 0.7 nights of wrist actigraphy at baseline and measures of IADL impairment, grip strength, and gait speed at baseline and 5-year follow-up.


RESULTS
After 5 years of follow-up, approximately 41% of participants had incident impairment in one or more IADLs. The quartile of women with the shortest total sleep time (TST) had 93% greater odds of incident IADL impairment than the longest sleepers (adjusted odds ratio (AOR) = 1.93, 95% confidence interval (CI) = 1.25-2.97). Similarly, the quartile of women with the lowest sleep efficiency (SE) had 65% greater odds of impairment than those with the highest (AOR = 1.65, 95% CI = 1.06-2.57). Women in the shortest TST quartile had twice the odds of declining grip strength as those with the longest TST (AOR = 1.97, 95% CI = 1.17-3.32). Finally, women in the quartiles with the most wake after sleep onset (WASO) and the lowest SE had approximately 90% greater odds of grip strength decline than those with the least WASO (AOR = 1.90, 95% CI = 1.11-3.24) and SE (AOR = 1.92, 95% CI = 1.12-3.29).


CONCLUSIONS
Findings indicate that shorter sleep duration, greater WASO, and lower SE are risk factors for functional or physical decline in older women.
Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA. aspira@jhsph.edu
Adam P
AP
Spira
Kenneth
K
Covinsky
George W
GW
Rebok
Naresh M
NM
Punjabi
Katie L
KL
Stone
Teresa A
TA
Hillier
Kristine E
KE
Ensrud
Kristine
K
Yaffe
D056044:Actigraphy; D000203:Activities of Daily Living; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D005684:Gait / Q000502:physiology; D015577:Geriatric Assessment; D018737:Hand Strength / Q000502:physiology; D006801:Humans; D016015:Logistic Models; D011446:Prospective Studies; D007319:Sleep Initiation and Maintenance Disorders / Q000175:diagnosis / Q000453:epidemiology / Q000503:physiopathology*; D011795:Surveys and Questionnaires; D014481:United States / Q000453:epidemiology