Omega-3 Does Not Prevent Relapse Of Crohn's Disease, Study Suggests

Effective therapy to maintain remission in Crohn disease (a chronic inflammatory disease primarily involving the small and large intestine) is an unmet medical need, with the use of some immunosuppressive drugs associated with an increased risk of infection.

"A significant amount of time and money is spent annually on alternative therapies such as Omega-3 fatty acids, without strong evidence that they are beneficial to patients with inflammatory bowel disease," says gastroenterologist Dr. Feagan, who is Director of Robarts Clinical Trials and lead author on the study. "I encourage Crohn's patients to focus on prescription medications that we know are effective for preventing relapse of disease, such as azathioprine, methotrexate, and TNF blockers."

Found in fatty fish such as salmon, mackerel, herring and sardines, omega-3 fatty acids have an anti-inflammatory effect and are therefore used in the treatment of inflammatory disorders such as rheumatoid arthritis and IgA nephropathy (a kidney disease).

The widespread belief among patients and health care providers that omega-3 fatty acids are effective treatment for inflammatory bowel disease may have stemmed from a relatively small Italian research study, published in 1996 in the New England Journal of Medicine, which found a benefit for preventing relapse of Crohn's disease.

"Small, single centre clinical trials often overestimate the true effects of treatment" says Dr. Feagan. "That's why it is important to conduct large-scale, randomized, multi-centre studies in order to confirm preliminary results."

Feagan's study includes two large-scale trials involving 738 Crohn's patients (ten times the number of patients involved in the original New England study) at clinical centres in Europe, Israel, Canada, and the United States from January 2003 to February 2007. Both trials demonstrated that the omega-3 fatty acid formulation offered no benefit in preventing relapse in Crohn's disease. However, patients who took the omega-3 fatty acid preparation did have significantly lower concentrations of triglycerides, a high level of which is a risk factor for heart disease.

Journal reference: JAMA. 2008;299[14]:1690-1697