Association of Dietary Live Microbes and Nondietary Prebiotic/Probiotic Intake With Cognitive Function in Older Adults: Evidence From NHANES

Abstract Background The current study aims to examine association of dietary live microbes and nondietary prebiotic/probiotic intake with cognitive function among older U.S. adults, examining heterogeneity across demographic characteristics and diseases. Methods Participants from the National Health and Nutrition Examination Survey 2011–2014 cycles were selected and administered 3 cognitive function tests: the Consortium to Establish a Registry for Alzheimer’s Disease Word Learning subtest (CERAD W-L, including immediate [CERAD-IRT] and delayed [CERAD-DRT] memory), the Animal Fluency Test (AFT), and the Digit Symbol Substitution Test (DSST). Test-specific and global cognition z-score was created. Based on their estimated dietary live microbes intake, participants were categorized into three groups: low, medium, and high. Text mining was employed to identify nondietary prebiotic/probiotic usage by examining the names and ingredients of dietary supplements or drugs. Results Participants in the medium (including AFT) and high (including global cognition, AFT, DSST, and CERAD-IRT) dietary live microbes intake group had significantly higher z-score of cognitive function compared to those in the low intake group. Among participants with cardiovascular disease history, nondietary prebiotic intake was associated with higher z-score in global cognition and CERAD-DRT compared to those who did not consume prebiotic. Additionally, probiotic intake was linked to higher z-score in global cognition, AFT, and DSST, particularly in participants with diabetes mellitus or hypertension. Conclusions Our study suggests that the intake of dietary live microbes and nondietary probiotic/prebiotic was associated with better cognitive function in older adults, particularly in specific disease states.