Polyunsaturated fatty acids in multiple sclerosis therapy

Abstract

Background: Results from epidemiological and uncontrolled intervention studies in multiple sclerosis (MS) suggest a beneficial disease-modifying effect of increased intake of polyunsaturated fatty acids (PUFAs). Objective: To review the current evidence from animal studies and randomised controlled trials on the therapeutic effect of PUFAs in MS. Methods: We searched PubMed and Medline for articles using the terms 'polyunsaturated fatty acids', 'eicosapentaenoic acid', 'docosahexaenoic acid', 'linoleic acid', 'linolenic acid', 'omega-3' and 'omega-6' combined with 'multiple sclerosis', 'randomised controlled trials', 'animal models', 'experimental autoimmune encephalomyelitis' and 'cuprizone'. The abstracts of retrieved citations were reviewed and checked for relevant content. Results: There was some evidence from animal model studies indicating an effect of ω-6 PUFAs, while the results from randomised controlled trials (RCTs) indicated that the ω-6 PUFAs linoleic acid or γ-linolenic acid have no beneficial effects on clinical disease activity in MS. However, the identified studies had several limitations in design with a mixture of relapsing-remitting and progressive MS patients. No studies investigated ω-6 efficacy on MRI disease activity. For ω-3 PUFAs, there was conflicting results from animal studies. RCTs show no beneficial treatment effect of the ω-3 PUFAs eicosapentaenoic acid and docosahexaenoic acid on MRI or clinical disease activity in MS. Conclusion: Randomised controlled trials of PUFA intervention provide no evidence of beneficial effects from ω-3 or ω-6 PUFAs on relapse rate, disability progression or MRI disease activity in MS. © 2012 John Wiley & Sons A/S.