Effects of a DHA rich n‐3 fatty acid supplementation on fatty acid composition in cerebrospinal fluid in Alzheimer disease. The OmegAD study

Abstract

BackgroundLittle is known about the transfer of essential fatty acids (FA) across the human blood‐brain barrier (BBB) in adulthood.ObjectiveWill oral supplementation for 6 mo with omega‐3 fatty acids (n‐3 FA), high in DHA, change the FA profile in cerebrospinal fluid (CSF) in patients with Alzheimer's disease (AD)?MethodsFA in CSF were analyzed by gas chromatography and mass spectrometry in 33 patients; 18 received n‐3 FA and 15 placebo. Participants were part of the OmegAD Study, where 204 patients with mild AD received 2.3 g n‐3 FA daily or placebo for 6 mo in a randomized fashion. Correlation analyses were made with plasma FA, CSF markers of AD and of inflammation.ResultsAt 6 mo a significant increase in CSF (and plasma) EPA, DHA and total n‐3 levels were noted in the n‐3 FA group, whereas no changes were observed in the placebo group. Changes of CSF DHA levels correlated significantly to changes of total and phosphorylated Tau and soluble IL‐1RII in CSF, i.e. the more the FA increased, the more the AD biomarkers decreased.SummaryN‐3 FA supplementation conferred discrete changes of n‐3 FA in CSF, suggesting transfer over the adult BBB. Significant correlations between CSF n‐3 FA and CSF AD markers suggest possible relationships.