New Heart Trials Put Omega-3s to the Test

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    In the first trial, reported at a recent meeting of the Heart Failure Society of America, Mihai Gheorghiade, MD, of North- western University, and colleagues compared the heart-health and exercise capacity of 98 patients randomly assigned to 850-882 milli- grams daily of either of the two main omega- 3s in fish oil (EPA and DHA), or a placebo. All the participants had been diagnosed with early-stage heart failure, a condition in which the heart muscle becomes unable to keep up with the bodys demands (not to be confused with a heart attack).After a year of followup including monthly assessments, patients getting the omega-3 supplements showed marked improvement in indicators of heart health compared to the placebo group. A test of left-ventricular function found that the omega-3 group had improved, while the placebo group got worse. The supplement group was also better able to exercise after 12 months, as measured by oxygen capacity.Those receiving omega-3 supplements were signifcantly less likely to be hospitalized for heart failure-only 6% compared to 30% in the placebo group. Omega-3 supplementa- tion was also associated with lower rates of hospitalization for any cardiovascular cause and overall hospitalization for any reason.Whether this intervention will have similar effects for patients with other conditions, more advanced stages of heart failure, or for patients who are not on evidence-based therapy remains unknown, Dr. Gheorghiade cautioned. I am hoping that further studies will be con- ducted to assess the effects of this potentially important therapy on left ventricular function and clinical outcomes in other patients.The fndings build on previous results from an Italian study that showed omega-3 supplements improved outcomes in patients with chronic heart failure.O n the other hand, results from a new Dutch clinical trial of heart-attack survivors-as opposed to heart-failure patients-were much less encouraging. Daan Kromhout, MPH, PhD, of Wageningen Univer- sity, and colleagues split 4,837 patients, ages 60-80, mostly men, into four groups: One got the omega-3s found in fsh (226 milligrams of EPA plus 150 of DHA), a second got 1.9 grams of the plant-derived omega-3 ALA, the third got both EPA/DHA and ALA, and the fourth got a placebo. All four were delivered in the form of an average 19 grams of margarine per day.Although the EPA/DHA margarine did initially reduce repeat cardiovascular events, after 30 months neither EPA/DHA nor ALA offered signifcantly more protection than the placebo. Researchers compared combined rates of fatal and non-fatal cardiovascular events and cardiac interventions; during the followup period, a major cardiovascular event occurred in 671 patients.All the patients also received state-of- the-art antihypertensive, antithrombotic and lipid-modifying therapy, according to Krom- hout and colleagues, publishing their fndings in the New England Journal of Medicine. They suggested that this optimal therapy, including statins, may have meant a benefcial effect of low doses of EPA-DHA is difficult to prove.It could also be that adding omega-3s to everything from margarine to trail mix isnt the best way to get your share of these healthy fats. Its still a good thing to eat fsh once or twice a week, Kromhout commented. The results of this trial do not change that.Alice H. Lichtenstein, DSc, director of Tufts HNRCA Cardiovascular Nutrition Labora- tory, pointed out that since the Dutch study focused on patients whod already suffered a heart attack, the results dont address whether long-term intake of EPA and DHA can help protect against a first heart attack. Higher intakes of omega-3s derived from fish might also be benefcial, she added, for patients who dont habitually eat fsh or arent receiving such state-of-the-art care. She noted that the strongest data linking omega-3s and reduced cardiovascular risk comes from observational studies relating the protective effect to regular fish consumption. Individuals who report regularly consuming fish also tend to be more physically active and less likely to smoke and to eat more fruits and vegetables.

    Heart Failure Society of America <www.hfsa.org>. New England Journal of Medicine, August 29, 2010; abstract at <www.nejm.org/doi/ full/10.1056/NEJMoa1003603>

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