The Multidomain Alzheimer's Preventive Trial (MAPT), led by Principal Investigator Professor Bruno Vellas, M.D., Geriatritian, chair Gérontopôle, University of Toulouse, was designed to assess the efficacy of supplementation with omega-3 fatty acid, multi-domain intervention or a combination of the two interventions on the change of cognitive functions in subjects 70 years and older with subjective memory complaints for a period of 3 years.

MAPT is a comprehensive program that consists of nutritional counseling, exercise, and cognitive and social stimulation, along with omega-3 fatty acid supplementation.

A group of nearly 1,700 older adults with memory complaints, slow walking speed, and limitation of at least one instrumental activity of daily living were enrolled in the study. Participants were randomized to one of four groups: placebo, omega-3 supplementation (800 mg DHA (docosahexaenoic acid) per day), placebo plus multidomain intervention, and omega-3 plus multidomain intervention.

Six months after starting the program, and then again at 12, 24, and 36 months, the participants were tested using a composite battery that evaluated cognitive domains. These included episodic memory, orientation, executive function, and verbal fluency. Pre-specified statistical analyses assessed the effect of several baseline variables on outcome, including cognitive scores, blood levels of DHA, and the presence of genetic marker ApoE4 linked with increased risk of developing Alzheimer's disease.

A secondary analysis showed that participants with low baseline DHA also showed significant benefits from the multidomain intervention plus DHA supplementation.

The clinical outcome clearly shows that omega-3 plus a healthy lifestyle (good nutrition, exercise, cognitive and social stimulation) can help maintain cognitive function as we age.

Participants receiving the multi-domain intervention plus DHA also resulted in statistically significant improvements in brain metabolism compared to controls. The results were more pronounced in people with the genetic marker ApoE4, and in those with evidence of amyloid deposition in the brain. By measuring red blood cell concentrations of DHA, people who could potentially benefit from omega-3 supplementation might be identified.

This research adds support to previous studies showing that omega-3 supplementation supports brain function.