Supplements of omega-3-rich fish oil may reduce the likelihood of developing psychotic disorders in high-risk people, say results of a new clinical trial.
Twelve weeks of supplementation with fish oil rich in EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid) reduced the risk of progression to full threshold psychosis by 22.6 per cent, compared to placebo, according to findings published in the Archives of General Psychiatry.
The link between omega-3 and cognitive function and behaviour is not new, with various studies reporting somewhat conflicting results for the omega-3 fatty acids EPA and DHA.
Some of the more promising data has been reported for DHA, with memory function improvements found for healthy older adults with a decline in cognitive function that occurs naturally with age, and known to precede diseases such as Alzheimer's.
The new study is the first of its kind to show benefits of omega-3 fatty acids in a help-seeking group at ultra-high risk of psychosis, claim the researchers, led by G. Paul Amminger from the Medical University of Vienna.
“The present trial strongly suggests that omga-3 PUFAs may offer a viable prevention and treatment strategy with minimal associated risk in young people at ultra-high risk of psychosis, which should be further explored,” they added.
Dr Amminger and his co-workers recruited 76 people at ultra-high risk of progression to psychosis. High-risk was defined as having mild psychotic symptoms, transient psychosis or a family history of psychotic disorders, in combination with a decrease in functioning. These criteria identify individuals whose risk of becoming psychotic may be as high as 40 percent in a 12-month period.
The researchers randomly assigned them to receive daily placebo (coconut oil) or supplements of fish oil containing 1.2 grams of omega-3 and providing 700 mg of EPA, 480 mg of DHA. After 12 weeks only 4.9 per cent of the omega-3 group had progressed to psychotic disorder, compared with 27.5 per cent of the placebo group.
Commenting on the potential mechanism the researchers noted that omega-3 fatty acids may produce changes in cell membranes and interactions with neurotransmitter systems in the brain. “The finding that […] a natural substance may prevent or at least delay the onset of psychotic disorder gives hope that there may be alternatives to antipsychotics for the prodromal [early symptomatic] phase,” wrote the authors.
“Stigmatization and adverse effects - which include metabolic changes, sexual dysfunction and weight gain - associated with the use of antipsychotics are often not acceptable for young people. [However, omega-3s], are free of clinically relevant adverse effects. They have the advantage of excellent tolerability, public acceptance, relatively low costs and benefits for general health,” they concluded.
Source: Archives of General Psychiatry
2010, Volume 67, Issue 2, Pages 146-154
“Long-Chain omega-3 Fatty Acids for Indicated Prevention of Psychotic Disorders: A Randomized, Placebo-Controlled Trial”
Authors: G.P. Amminger, M.R. Schafer, K. Papageorgiou, C.M. Klier, S.M. Cotton, S.M. Harrigan, A. Mackinnon, P.D. McGorry, G.E. Berger