COPD, Dietary Fiber Intake, and Cognitive Performance in Older Adults: A Cross-Sectional Study from NHANES 2011-2014.

INTRODUCTION: This study aimed to evaluate the modifying role of dietary fiber intake in the relationship between COPD and cognitive performance.

METHODS: Data of adults aged ≥60 years were extracted from the National Health and Nutrition Examination Survey (NHANES) 2011-2014. Participants with information on cognitive function measures were included. Dietary fiber intake, identified using participants' 24-h recall surveys, was grouped into high (>25 g/day) and low (≤25 g/day) levels. COPD was identified through self-reported physician diagnoses. Associations between dietary fiber intake, cognitive function and COPD were evaluated using the regression analysis.

RESULTS: Data of 2,189 participants were analyzed. Multivariate analysis revealed that COPD was significantly associated with lowered CERAD (adjusted beta [aBeta]: -0.17, 95% confidence interval [CI]: -0.33 to -0.002, p  = .047) and DSST (aBeta: -2.23, 95% CI: -4.25 to -0.2, p = .032) scores in older adults. The analysis on the association between COPD and cognitive function stratified by dietary fiber intake revealed that COPD remained significantly associated with lowered CREAD among individuals with a high fiber intake (aBeta: -0.54, 95% CI: -1.00 to -0.08, p  = .024).

CONCLUSIONS: In US older adults, COPD is associated with reduced cognitive function. However, the findings do not support that high dietary fiber intake may modify the association between COPD and cognitive impairment.