Abstract
INTRODUCTION: We report the feasibility and cognitive outcomes of a stage 1b randomized trial testing 3 months of home-delivered high polyphenol snacks (e.g., nuts, berries) and online speed of processing training among older adults with 12 or fewer years of education. METHODS: One hundred eighty participants were randomized to polyphenol-rich snacks and online cognitive training, polyphenol snacks and online control games, control snacks and cognitive training, or control snacks and control games. The outcomes were feasibility of recruitment, retention, and adherence (RRA) and change in a cognitive composite score. RESULTS: Feasibility goals for RRA were met. Improvements in the cognitive score were evident in all groups (effect sizes ranged from 0.15-0.35) but improvements did not differ significantly between arms. DISCUSSION: Dementia prevention trials with longer intervention and follow-up focused on adults with limited formal education should be considered given the observed cognitive gains in those with elevated risk. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov (NCT03419052). HIGHLIGHTS: The study focused on adults with low education; a group with a high risk for cognitive decline. Two interventions were tested in a randomized trial design that included two controls. Nutrition intervention was designed with input from adults with limited education. PRIMARY OUTCOME: A cognitive composite score was formed from five established cognitive tests. The study establishes the feasibility of dementia prevention targeting adults with low education.