Independent and joint role of inflammatory diet and physical activity with cognitive function in aging: Evidence from a population-based survey

Abstract

Objective

This study aims to explore the independent and joint association of physical activity (PA) and inflammatory diet with cognitive function in aging.

Method

Data from the 2011–2014 National Health and Nutrition Examination Survey (NHANES) was used. 2249 NHANES participants with valid data represented a weighted population of 50.5 million American residents aged 60 and older. This study separately analyzed the independent associations of PA (measured by global physical activity questionnaire) and inflammatory diet (measured by energy-adjusted dietary inflammatory index from 24-h dietary recall), and their joints (inactive & pro-inflammatory as reference) with cognitive function (assessed by three cognitive tests), and considered an individual of different status and non-linear effect by sub-group and restricted cubic splines (RCS) analysis, respectively. All analysis was multivariable-adjusted and sample-weighted.

Results

The results showed that inflammatory diet was independently associated with lower cognitive function, with a 1.08, 1.29, 2.67, 0.56 lower score in the Registry for Alzheimer's Disease word list learning test (CERAD), the Animal Fluency Test (AFT), the Digit Symbol Substitution test (DSST), Z-scores, and 51 %, 62 %, 63 %, 93 % higher odds ratio (OR) of lower performance in CERAD, AFT, DSST, and p-MCI, respectively. PA was independently associated with higher cognitive function, with a 1.41, 3.37, and 0.52 higher score in AFT, DSST, Z-scores, and 28 %, 51 %, 41 % lower ORs of lower performance in CERAD and DSST and p-MCI, respectively. Active & Anti-inflammatory was always positively associated with cognitive function, with a 1.42, 2.69, 5.47, and 1.04 higher score for CERAD, AFT, DSST, and Z-score, a 58 %, 56 %, 74 %, 76 % lower ORs of lower performance in CERAT, AFT, DSST, and p-MCI, respectively, which elicited the maximum compared to other joints.

Conclusion

Adhering to both active PA and anti-inflammatory diet is recommended for cognitive management in older adults. Sticking to either active PA or anti-inflammatory diet also shows potential cognitive benefits, with the diet possibly playing more vital role.