Background: Epidemiologic and animal studies have suggested that dietary fish or fish oil rich in-3 fatty acids, for example, docosahexaenoic acid and eicosapentaenoic acid, may prevent Alzheimer disease (AD). Objective: To determine effects of dietary-3 fatty acid supplementation on cognitive functions in patients with mild to moderate AD. Design: Randomized, double-blind, placebo-controlled clinical trial. Participants: Two hundred four patients with AD (age range [mean±SD], 74 ± 9 years) whose conditions were stable while receiving acetylcholine esterase inhibitor treatment and who had a Mini-Mental State Examination (MMSE) score of 15 points or more were randomized to daily intake of 1.7 g of docosahexaenoic acid and 0.6 g of eicosapentaenoic acid (-3 fatty acid-treated group) or placebo for 6 months, after which all received-3 fatty acid supplementation for 6 months more.

The physical activity parameters of MHD patients were compatible with a sedentary lifestyle. This inactivity was worsened by aging, diabetes and higher BMI. Our results indicate that MHD patients should be encouraged by the health care team to increase their physical activity.

Supplementation with omega3 in patients with mild to moderate AD did not result in marked effects on neuropsychiatric symptoms except for possible positive effects on depressive symptoms (assessed by MADRS) in non-APOEomega4 carriers and agitation symptoms (assessed by NPI) in APOEomega4 carriers. ClinicalTrials.gov identifier: NCT00211159