Interaction between composite dietary antioxidant index and physical activity on cognitive impairment in the elderly: NHANES 2011–2014

Objective: We aim to explore the association between the Composite Dietary Antioxidant Index (CDAI), physical activity, and cognitive impairment. Methods: 2395 participants from the 2011–2014 National Health and Nutrition Examination Survey (NHANES) were included in this study. The association of CDAI and physical activity with cognitive impairment was analyzed using binary logistic regression. A stratified analysis was employed for a sensitivity analysis of the logistic regression, examining the interaction between CDAI and each stratified variable. Results: Both low scores on CDAI and physical inactivity are associated with higher prevalence of cognitive impairment. Compared to the fourth quartile of CDAI and active group, the prevalence of cognitive impairment is statistically increased in other sub-groups. Conclusion: There is an interaction between CDAI and physical activity. The elderly population with low scores on CDAI especially combined with physical inactivity should be focused, so as to reduce the adverse effects of cognitive impairment.