Background: Available evidence on the association of physical activity (PA) or sedentary behavior with cognitive decline is inconclusive.
Objective: To assess the association between an active lifestyle score and leisure-time physical activity (LTPA) and changes in cognitive function in the Seguimiento Universidad de Navarra (SUN) prospective cohort.
Methods: Cognitive function was evaluated in a subsample of 806 participants of the SUN cohort study using the validated Telephone Interview for Cognitive Status-modified (STICS-m) questionnaire at baseline and after 6 years. LTPA was evaluated with a previously validated 17-item self-administered questionnaire and with information on sedentary lifestyles. We also calculated a multidimensional 8-item PA score. Multivariable linear regression analysis evaluated the association between PA and changes in cognitive function and its interaction by APOE genotype.
Results: Mean age of participants was 66 (SD 5.3) years and 69.7% were male. When stratifying by APOE variants, no significant associations between the active lifestyle score or LTPA and changes in cognitive performance over time were found among APOE ɛ4 carriers. However, we observed that a higher adherence to an active lifestyle (high versus low PA score β= 0.76 95% CI 0.15,1.36; p trend = 0.011) and a high LTPA (Q4 versus Q1 β= 0.63; 95% CI -0.01,1.26; p trend = 0.030) were associated with more favorable changes in cognitive function over time among APOE ɛ4 non-carriers with statistically significant interactions in both cases (p for interaction = 0.042 for PA score, and p = 0.039 for LTPA).
Conclusion: The results of the present study suggest that an active lifestyle is associated with a better status of cognitive function over time only among APOE ɛ4 non-carriers.
Keywords: APOE; cognition; cognitive function; exercise; physical activity; prospective study; sedentarism.