Lower Risk of Heart Failure Linked to Higher Blood EPA Levels

In congestive heart failure, the heart is unable to pump sufficient blood for the rest of the body’s needs. The condition can develop as a result of coronary artery disease, high blood pressure, obesity, diabetes or other disorder. About 75% of patients with heart failure have hypertension, but a previous heart attack (myocardial infarction) also poses a high risk of the condition. After the age of 40, the chance of developing heart failure is 1 in 5 for both men and women. According to the American Heart Association, about half the people with heart failure die within 5 years. Can someone with heart failure beat the odds? There are habits that can reduce the risk of this condition becoming worse. Many of these relate to lifestyle – avoiding smoking, limiting alcohol intake, exercising regularly (except if you experience fluid accumulation) and achieving a desirable body weight. Researchers are trying to determine if increasing fish intake, especially of fatty fish, can also be beneficial. Some observational studies have reported that people who eat fish regularly are less likely to develop heart failure, but others have found no relationship among older adults between fish consumption and developing heart failure. In a new study by researchers in Boston, USA, investigators examined the fatty acid content of blood in patients who developed heart failure and those who did not. By looking at the actual levels of fatty acids in the blood rather than estimating fatty acid status from dietary fish intake, the investigators hoped to obtain a more accurate assessment of the omega-3 fatty acid status of the participants. The participants were monitored for up to 14 years and 3 criteria were used to confirm a diagnosis of heart failure. The omega-3 fatty acid status of the patients was of particular interest because these substances have been associated with significantly lower risks of cardiovascular disease and mortality and of several heart health risk factors, such as heart rate. When the risk of heart failure was calculated for each of the 3 main omega-3s—EPA, DPA and DHA—plus total long-chain omega-3s after 7 years of follow-up, higher levels of EPA, DPA and total long-chain omega-3s were each associated with a significantly lower risk of heart failure. Interestingly, higher levels of DHA were not associated with a lower risk of heart failure. DHA has been favorably associated with a lower risk of many aspects of heart disease, but in this study risk of heart failure was not one of them. It was also noted in the paper that higher fish consumption by itself was not related to the risk of heart failure. Nevertheless, fish is one source of EPA. Fish oil supplements, most of which have more EPA than DHA, are another. To put this paper in perspective, observational studies have come down on both sides of the question, some being supportive, others finding no effect of fish or long-chain omega-3s on the risk of developing heart failure. The study does not say, however, that eating fish or long-chain omega-3s is of no value in heart health. It means that if EPA turns out to be a key factor in reducing the chance of this particular condition, sources rich in EPA rather than DHA may be the most effective. It will take more definitive evidence to verify whether this possibility is true. Further, both DHA and EPA appear to be important in reducing the risk of other aspects of heart disease, which also affect people at risk of heart failure.