Docosahexaenoic acid-concentrated fish oil supplementation in subjects with mild cognitive impairment (MCI): a 12-month randomised, double-blind, placebo-controlled trial

RATIONALE: Epidemiological studies have suggested a beneficial effect of fish oil supplementation in halting the initial progression of Alzheimer's disease. However, it remains unclear whether fish oil affects cognitive function in older people with mild cognitive impairment (MCI).

OBJECTIVES: This study investigated the effects of fish oil supplementation on cognitive function in elderly person with MCI.

METHODS: This was a 12-month, randomised, double-blind, placebo-controlled study using fish oil supplementation with concentrated docosahexaenoic acid (DHA). Thirty six low-socioeconomic-status elderly subjects with MCI were randomly assigned to receive either concentrated DHA fish oil (n = 18) or placebo (n = 18) capsules. The changes of memory, psychomotor speed, executive function and attention, and visual-constructive skills were assessed using cognitive tests. Secondary outcomes were safety and tolerability of the DHA concentrate.

RESULTS: The fish oil group showed significant improvement in short-term and working memory (F = 9.890; ηp (2) = 0.254; p