Age- and sex-related differences in sleep patterns and their relations to self-reported sleep and mood.
Level 3 - non-randomized controlled study
Cross-sectional observational analysis of a cohort with internal split-sample replication
PubMed 41333185 · doi:10.1093/sleepadvances/zpaf079
What was done
Analyzed week-long wrist actigraphy data and self-reported sleep and mood measures (depression and anhedonia) in UK Biobank participants aged 44 to 82 years. The dataset was divided into a discovery cohort (n = 38,546) and an internal replication cohort (n = 38,547) to examine age- and sex-related variations in objective sleep features and their links to subjective sleep complaints and mood.
What was found
Younger women slept about 17 minutes more than age-matched men, a difference that narrowed with advancing age as both sexes showed reduced total sleep duration in later life. Middle-aged participants had shorter sleep durations during the week and extended sleep on weekends by up to 50 minutes, whereas individuals in their 60s and 70s maintained more consistent sleep patterns throughout the week. Self-reported depression and anhedonia were associated with reduced total sleep duration across multiple age groups and both sexes.
Why it matters
It establishes large-scale, population-level actigraphy benchmarks for how sleep duration and weekly variability change across mid-to-late life by sex, linking reduced objective sleep duration to self-reported mood symptoms.
Limits
The cross-sectional observational design precludes causal inferences regarding sleep patterns and mood. Actigraphy was limited to a single week, which may not capture seasonal or long-term variations. The sample was restricted to UK Biobank participants aged 44–82, limiting generalizability to younger populations or non-UK cohorts.