Supplementation with omega-3 fatty acids has no benefit on the disease activity of multiple sclerosis, according to data from a new clinical trial the authors acknowledged was underpowered.
The study – published in JAMAs Archives of Neurology – investigated the effects of omega-3 fatty acid supplementation as a single therapy or in combination with interferon beta-1a (a drug used in the treatment of multiple sclerosis) on the effects of multiple sclerosis disease activity.
Led by Dr Øivind Torkildsen from Haukeland University Hospital, Norway the research team assessed 92 patients with multiple sclerosis in the double-blind, placebo-controlled trial. They reported that omega-3 supplements were not associated with beneficial effects on disease activity in patients with relapsing-remitting multiple sclerosis (MS).
"The results from this study did not show any beneficial effects of omega-3 fatty acid supplementation on disease activity in multiple sclerosis as a monotherapy or in combination with interferon beta," said Torkildsen and his colleagues, who noted that their results were in contrast with two other studies reporting a possible positive effect.
"The design of this study allowed us to compare the effect of omega-3 fatty acid supplementation both against placebo alone and in combination with interferon beta. As expected, the MRI disease activity was significantly reduced when interferon beta-1a was introduced," they concluded.
Commenting on the study, Dr Carrie Ruxton of the Health Supplements Information Service, noted that omega-3 fatty acids are essential nutrients, not drugs, and are not intended to be used for the treatment of any disease.
“It is important to evaluate this study in the context of others that have shown inverse associations between blood levels of omega-3 fatty acids and markers of disease activity in multiple sclerosis,” she said.
Ruxton added that it was also important to note that intakes of omega-3 are on average lower than recommended, and as such intakes need to increase in general.
Harry Rice, PhD, VP of regulatory and scientific affairs for the Global Organization for EPA and DHA Omega-3 (GOED) told NutraIngredients, that he believed, “the authors stated it best when they acknowledged that the '...sample size did not have sufficient power to detect small and medium treatment effect sizes, both with respect to MRI and clinical disease activity.’
“Even if the ultimate conclusion is that EPA and DHA do not affect disease activity in relapsing-remitting Multiple Sclerosis (MS), this does not mean that they don’t play a role in MS development or even in the progression of the three other courses of MS, including: primary progressive, secondary progressive and progressive relapsing,” said Rice.
Half of the 92 patients (46) were given omega-3 supplements – containing 1350 mg of eicosapentaenoic acid and 850 mg of docosahexaenoic acid – daily, whilst the other half were administered placebo.
After six months, all patients received interferon beta-1a three times a week for another 18 months.
Researchers used magnetic resonance imaging (MRI) to measure disease activity by the number of new lesions in the brain.
Torkildsen and his team said that there was no difference between the two groups in the number of relapses or lesions during the first six months of treatment or after 24 months. In addition, no differences were detected either in fatigue or quality-of-life scores.
Rice said that whilst the use of a MRI endpoint was ‘spot on’: “The reality is that results from an under-powered study cannot be interpreted with any certainty.”
“If you look at the totality of scientific evidence, it remains inconclusive as to what role, if any, omega-3s play in the management of relapsing-remitting MS.”
The authors commented that their data does not suggest omega-3 fatty acid supplementation is harmful, or that such supplementation interfered with interferon beta treatment – which they noted can reduce disease activity in the relapsing-remitting course of the disease.
Source: Archives of Neurology
Published online ahead of print, doi: 10.1001/archneurol.2012.283
"Omega-3 Fatty Acid Treatment in Multiple Sclerosis (OFAMS Study): A Randomized, Double-Blind, Placebo-Controlled Trial"
Authors: Ø. Torkildsen, S. Wergeland, S. Bakke, A.G. Beiske, K.S. Bjerve