A new study suggests that sleeping for longer periods may be linked to higher levels of a blood protein associated with Alzheimer’s disease. Researchers focused on plasma p-tau181, a biomarker increasingly used to study changes connected to neurodegeneration.
Using advanced non-linear spline modeling, the team examined data from more than 2,400 older adults. Their analysis pointed to a curved rather than straight-line relationship, indicating that the association between sleep duration and the biomarker changes across different sleep lengths.
The key finding was that regularly longer sleep was associated with elevated plasma p-tau181 levels. Because the pattern was non-linear, the results suggest the biological connection may become more noticeable at the high end of sleep duration instead of rising evenly with every additional hour.
The research adds to growing interest in how sleep habits may reflect or relate to brain health in aging. While the study highlights a meaningful association, it does not by itself show that longer sleep causes Alzheimer’s-related changes, but it does reinforce the value of sleep patterns as a potential clue in dementia research.
