Physical activity and brain amyloid beta: A longitudinal analysis of cognitively unimpaired older adults

INTRODUCTION The current study evaluated the relationship between habitual physical activity (PA) levels and brain amyloid beta (A beta) over 15 years in a cohort of cognitively unimpaired older adults.METHODS PA and A beta measures were collected over multiple timepoints from 731 cognitively unimpaired older adults participating in the Australian Imaging, Biomarkers and Lifestyle (AIBL) Study of Aging. Regression modeling examined cross-sectional and longitudinal relationships between PA and brain A beta. Moderation analyses examined apolipoprotein E (APOE) epsilon 4 carriage impact on the PA-A beta relationship.RESULTSPA was not associated with brain A beta at baseline (beta = -0.001, p = 0.72) or over time (beta = -0.26, p = 0.24). APOE epsilon 4 status did not moderate the PA-A beta relationship over time (beta = 0.12, p = 0.73). Brain A beta levels did not predict PA trajectory (beta = -54.26, p = 0.59).DISCUSSION Our study did not identify a relationship between habitual PA and brain A beta levels.Highlights Physical activity levels did not predict brain amyloid beta (A beta) levels over time in cognitively unimpaired older adults (>= 60 years of age). Apolipoprotein E (APOE) epsilon 4 carrier status did not moderate the physical activity-brain A beta relationship over time. Physical activity trajectories were not impacted by brain A beta levels.

Automated summary

The study found no significant relationship between habitual physical activity and brain amyloid beta levels in cognitively unimpaired older adults, nor did apolipoprotein E (APOE) ε4 carrier status moderate this relationship.