INSUFFICIENT weekday sleep may elevate the risk of dementia, but new research suggests that weekend recovery sleep can mitigate this risk for certain dementia subtypes. A large prospective cohort analysis of the UK Biobank has provided new insights into how weekend sleep patterns influence long-term cognitive outcomes.
The study followed 88,592 dementia-free adults between the ages of 40 and 79 years, with an average age of 61.9 years at baseline. Wrist-worn accelerometers were used to capture weekday and weekend sleep durations. Over the follow-up period, 735 participants (0.83%) developed dementia, including 308 cases of Alzheimer’s disease, 137 cases of vascular dementia, and 319 cases of nonspecific dementia.
Analyses using Cox proportional hazards models and restricted cubic splines revealed that optimal weekday sleep durations were associated with the lowest dementia risk. The estimated optimal thresholds were 8.38 hours for all-cause dementia, 8.33 hours for Alzheimer’s disease, and 9.07 hours for vascular dementia. Participants who routinely slept less than these optimal durations during the week experienced a protective effect from longer weekend recovery sleep. Specifically, additional weekend sleep was linked to reduced risk of all-cause dementia (HR: 0.801; 95% CI: 0.717–0.893) and vascular dementia (HR: 0.747; 95% CI: 0.612–0.91).
However, not all groups benefitted. Among individuals with prolonged weekday sleep exceeding optimal durations, longer weekend recovery sleep was associated with an elevated risk of nonspecific dementia (HR: 1.291; 95% CI: 1.087–1.533). These findings highlight the nuanced relationship between weekday sleep patterns, weekend recovery behaviors, and dementia subtypes.
The investigators concluded that adequate weekend recovery sleep may reduce the risk of dementia, particularly vascular dementia, in adults with insufficient weekday sleep. This emphasizes the importance of maintaining balanced sleep patterns for cognitive health across the lifespan.
Reference: Zhao B et al. Association between weekend recovery sleep and risk of incident dementia: a prospective cohort study in the UK Biobank. J Neurol. 2025;272(9):612.
