Does Body Mass Index Modify Memory, Reasoning, and Speed of Processing Training Effects in Older Adults

Abstract

Objective To describe 10-year trajectories of cognitive performance by body mass index (BMI) class and to investigate BMI differences in response to memory, reasoning, and speed of processing training in older adults. Methods This is a secondary analysis of the multisite, randomized trial Advanced Cognitive Training for Independent and Vital Elderly. There were 701 older adults with normal weight, 1,081 with overweight, and 902 with obesity (mean age 73.6) randomized to memory training, reasoning training, speed of processing training, or no-training control group. Participants completed memory, reasoning, and speed of processing tests. Baseline sociodemographic, health, and chronic disease measures were included as covariates in analyses. Results The 10-year trajectories of memory, reasoning, or speed of processing performance did not differ by BMI status among the participants randomized to the untrained control arm. The training effect on the reasoning and speed of processing outcomes did not differ by BMI status. The training effect on the memory outcome in participants with a BMI indicating obesity, however, was just 38% of that observed in participants with normal-weight BMI. Conclusions These analyses of data from the largest trial of cognitive training ever conducted suggest that older adults with obesity may be less responsive to memory training.