DHA supplement not associated with slower cognitive, functional decline in mild to moderate Alzheimer's disease

Docosahexaenoic acid (DHA) supplementation doesn’t appear to slow the rate of cognitive and functional decline in individuals with mild to moderate Alzheimer’s disease, according to research published in the Journal of the American Medical Association, HealthDay News reported.

Joseph F. Quinn, MD, of the Oregon Health and Science University, and colleagues analyzed data from 402 patients with mild to moderate Alzheimer’s who were randomized to receive 2 g of algal DHA or placebo daily for 18 months. Of this group, 295 completed the trial while taking study medication. Outcomes included change in the cognitive subscale of the Alzheimer’s Disease Assessment Scale (ADAS-cog) and the Clinical Dementia Rating (CDR) sum of boxes.

Researchers found that DHA supplementation didn’t show a benefit for rate of change on the ADAS-cog score, and wasn’t associated with a difference in CDR sum of boxes score. Among a subgroup that underwent magnetic resonance imaging at baseline and 18 months, DHA treatment didn’t affect the rate of brain atrophy.

Several co-authors disclosed both involvement with a patent related to this issue and relationships with Martek Biosciences, which provided the drug, placebo, and other support for the study. The author of an accompanying editorial disclosed relationships with several pharmaceutical companies.