The Association Between Dietary Pattern Adherence, Cognitive Stimulating Lifestyle, and Cognitive Function Among Older Adults From the Quebec Longitudinal Study on Nutrition and Successful Aging.

OBJECTIVE This study examined the effect of dietary patterns and engagement in cognitive stimulating lifestyle behaviours on trajectory of global cognition, executive function (EF), and verbal episodic memory (VEM). METHOD Western and prudent dietary patterns were empirically derived using food frequency questionnaire responses from 350 community-dwelling older adults (mean age: 73.7 years) participating in the Quebec Longitudinal Study on Nutrition and Successful Aging. Cognitive stimulating lifestyle (CSL) was represented by a binary composite indicator based on education, occupational complexity, and social engagement. Global cognition, EF, and VEM were assessed prospectively. RESULTS Primary effect models revealed an association between higher Western dietary pattern score and greater rate of decline in global cognition and EF. Higher Western dietary pattern adherence also associated with poorer baseline VEM.. Primary effect models also revealed that CSL independently associated with baseline global cognition and EF. Effect modification models suggested an interactive effect between Western dietary pattern and CLS on global cognition only. No associations were found for prudent dietary pattern score. DISCUSSION Contributing to existing research supporting the negative impact of consuming an unhealthy diet on cognitive function, the current study suggests increased vulnerability among older adults who do not engage in a cognitive stimulating lifestyle. These findings can inform the development of lifestyle intervention programs that target brain health in later adulthood.