Research

Mixed

High wake after sleep onset (WASO ≥1.6 hours) is associated with significantly higher odds (1.8x) of functional limitations in older women, independent of sleep duration.

Frequent nighttime awakenings (over 1.6 hours of being awake after initially falling asleep) are strongly linked to difficulty with daily activities like shopping or climbing stairs. Improving sleep continuity, even if total sleep time is adequate, may help maintain physical independence.

GoodSupportsHIGH confidence
With higher wake after sleep onset (≥1.6 hours compared to <0.7 hours) gait speed was 9.1% slower; it took 7.6% longer to complete 5 chair stands, and odds of functional limitation were 1.8 (95% CI: 1.4, 2.4) higher.
Suzanne E. Goldman et al. · SLEEP · 2007

Why this rating

Large sample, objective measures, adjusted for confounders, but cross-sectional design limits causal inference.

Source

Poor Sleep is Associated with Poorer Physical Performance and Greater Functional Limitations in Older Women

Suzanne E. Goldman et al. · SLEEP · 2007

DOI 10.1093/sleep/30.10.1317

cohort · n=2889Cited 277×
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DOI resolved against Crossref · corpus check 2026-06-10

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