Rest-Activity Rhythm Characteristics and Cognitive Function in Cognitively Healthy Older Adults.

Background/objective: Rest-activity rhythm (RAR) describes the pattern of physical activity and rest periods in 24 hr. This study investigated the association between RAR and cognitive performance among older adults.

Methods: Sixty community-dwelling older adults aged 70 ± 7.3 years (mean ± standard deviation) wore an Actiwatch Spectrum Plus for 2 weeks and completed a neuropsychological battery to assess cognition. RAR parameters were analyzed using the cosinor approach, with a primary focus on mesor (mean activity level) and pseudo-F-statistics (the rhythmicity of RAR). Cognitive measures assessed immediate memory, memory recall, executive functioning, and processing speed. Multiple linear regression modeling was used to examine associations.

Results: RAR mesor was associated with processing speed after adjustment for covariates (β = 12.78, p < .05). Pseudo-F-statistics were associated with immediate memory (β = 2.65, p < .05) and memory recall (β = 4.27, p < .05) in adjusted models.

Conclusion: Our study contributes novel insights into the intricate relationship between RAR parameters and cognitive function in later life adults. We found positive associations between RAR mesor and processing speed as well as pseudo-F-statistics and memory in later life adults. Significance/Implications: These findings have potential implications for both research and clinical practice. For researchers, there is a need for further exploration of the complex associations between RAR and cognitive health, preferably through large-scale, diverse, longitudinal studies. From a practical perspective, understanding these associations may guide the development of interventions aimed at promoting cognitive health.