Objective: The aim of this study was to investigate whether the use of fish oil supplements (FOSs) is associated with concomitant reduction in cognitive decline and brain atrophy in older adults.
Methods: We conducted a retrospective cohort study to examine the relationship between FOS use during the Alzheimer’s Disease Neuroimaging Initiative and indicators of cognitive decline. Older adults (229 cognitively normal individuals, 397 patients with mild cognitive impairment, and 193 patients with Alzheimer’s disease) were assessed with neuropsychological tests and brain magnetic resonance imaging every 6 months. Primary outcomes included (1) global cognitive status and (2) cerebral cortex gray matter and hippocampus and ventricular volumes.
Results: FOS use during follow-up was associated with significantly lower mean cognitive subscale of the Alzheimer’s Disease Assessment Scale and higher Mini-Mental State Examination scores among those with normal cognition. Associations between FOS use and the outcomes were observed only in APOE ε4–negative participants. FOS use during the study was also associated with less atrophy in one or more brain regions of interest.