Clinical Manifestations

Area of Science:

• Gerontology
• Sleep Medicine
• Cognitive Neuroscience

Background:

• Sleep disturbances are prevalent in older adults and associated with cognitive impairment risk.
• Longitudinal data on sleep changes and cognitive performance in this demographic are scarce.
• Understanding these relationships is crucial for identifying early markers of cognitive decline.

Purpose of the Study:

• To investigate if longitudinal sleep patterns, measured by actigraphy, differ across distinct cognitive trajectories in older adults.
• To examine the association between changes in global cognition and changes in sleep parameters over time.

Main Methods:

• Utilized data from 219 participants in the Einstein Aging Study, with a median follow-up of 4 years.
• Actigraphy was used annually to assess sleep duration, wake after sleep onset (WASO), and sleep efficiency.
• Latent class mixed-effects models identified cognitive trajectories (Consistently High, Medium, Declining) based on the telephone Montreal Cognitive Assessment (T-MoCA).

Main Results:

• Three cognitive trajectory groups were identified: Consistently High (N=126), Medium (N=82), and Declining (N=11).
• Significant differences were observed in longitudinal patterns of night-time sleep duration, WASO, and sleep efficiency across these cognitive groups (p < 0.001).
• The declining cognitive group showed steeper decreases in sleep duration and greater improvements in WASO and efficiency compared to other groups.

Conclusions:

• Actigraphy-based sleep changes over five years are distinct among older adults with different cognitive trajectories.
• More pronounced sleep alterations in the declining cognitive group may indicate underlying neurodegenerative processes impacting sleep.
• Further research with larger samples is needed to confirm these findings and their implications.