Effects of n-3 fatty acids, EPA v. DHA, on depressive symptoms, quality of life, memory and executive function in older adults with mild cognitive impairment: a 6-month randomised controlled trial
Sinn, N and Milte, CM and Street, S and Buckley, JD and Coates, AM and Petkov, J and Howe, PR, Effects of n-3 fatty acids, EPA v. DHA, on depressive symptoms, quality of life, memory and executive function in older adults with mild cognitive impairment: a 6-month randomised controlled trial, The British Journal of Nutrition: an international journal of nutritional science, 107 pp. 1682-1693. ISSN 0007-1145 (2012) [Refereed Article]
Depressive symptoms may increase the risk of progressing from mild cognitive impairment (MCI) to dementia. Consumption of n-3 PUFA
may alleviate both cognitive decline and depression. The aim of the present study was to investigate the benefits of supplementing a diet
with n-3 PUFA, DHA and EPA, for depressive symptoms, quality of life (QOL) and cognition in elderly people with MCI. We conducted a
6-month double-blind, randomised controlled trial. A total of fifty people aged .65 years with MCI were allocated to receive a supplement
rich in EPA (1·67 g EPA þ 0·16 g DHA/d; n 17), DHA (1·55 g DHA þ 0·40 g EPA/d; n 18) or the n-6 PUFA linoleic acid (LA; 2·2 g/d; n 15).
Treatment allocation was by minimisation based on age, sex and depressive symptoms (Geriatric Depression Scale, GDS). Physiological
and cognitive assessments, questionnaires and fatty acid composition of erythrocytes were obtained at baseline and 6 months (completers:
n 40; EPA n 13, DHA n 16, LA n 11). Compared with the LA group, GDS scores improved in the EPA (P¼0·04) and DHA (P¼0·01) groups
and verbal fluency (Initial Letter Fluency) in the DHA group (P¼0·04). Improved GDS scores were correlated with increased DHA plus EPA
(r 0·39, P¼0·02). Improved self-reported physical health was associated with increased DHA. There were no treatment effects on other
cognitive or QOL parameters. Increased intakes of DHA and EPA benefited mental health in older people with MCI. Increasing n-3
PUFA intakes may reduce depressive symptoms and the risk of progressing to dementia. This needs to be investigated in larger, depressed
samples with MCI.
Mild cognitive impairment: Dementia: Depression: n-3 Fatty acids: EPA: DHA