Reduced omega-3 and elevated trans-fatty acid levels predict nonfatal heart attack better than established risk factors

An article published online on June 9, 2009 in the British Journal of Nutrition reported the conclusion of a study conducted by South Korean researchers that red blood cell fatty acid profiles may prove to be a better predictor of who is at risk of heart disease than Framingham risk factors.

Framingham risk scores are calculated from values for the following traditional risk factors: age, gender, smoking status, total cholesterol levels, HDL-cholesterol levels, diabetes history and hypertension history. While an individual’s Framingham score is 70 to 80 percent accurate in predicting coronary heart disease risk, it fails to take into account more recently recognized risk factors that could improve its predictive value.

The researchers, from the Hanyang University in Seoul, matched 50 men and women with acute nonfatal myocardial infarction (heart attack) with 50 age and gender-matched controls who did not have a history of heart attack. Red blood cells were analyzed for levels of trans-fatty acids (undesirable fatty acids found in partially hydrogenated vegetable oil), and the beneficial omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) (found in fish and the algae they feed on). Continue Reading

High omega-3 diet of Japanese linked with significantly lower heart disease risk compared to Americans

The number of deaths from coronary heart disease among Japanese men is less than half that of American men. Whether this effect is due to genetic, dietary or other factors has not been confirmed. In the first international study of its kind, published in the August 5, 2008, issue of Journal of the American College of Cardiology, University of Pittsburgh Graduate School of Public Health assistant professor of epidemiology Akira Sekikawa, MD, PhD, and colleagues evaluated data from 868 men aged 40 to 49 enrolled in the ERA JUMP (Electron-Beam Tomography, Risk Factor Assessment Among Japanese and U.S. Men in the Post-World War II Birth Cohort) Study. Two hundred eighty-one of the current study’s subjects were from Japan; 306 were Caucasian men from Pennsylvania; and 281 were Japanese-American men living in Hawaii. Blood tests measured total fatty acids, and the omega-3 fatty acids eicosapentaenoic, docosahexaenoic, and docosapentaenoic acids, which are commonly obtained by consuming fish. Ultrasound examination assessed carotid artery intima-medial thickness (IMT), which is used to evaluate atherosclerosis. Coronary artery calcification (CAC) in the heart’s arteries, which also identifies heart disease, was assessed via electron-beam CT scanner.

Although total fatty acid levels were similar among all subjects, the percentage of fish-based omega-3 fatty acids was twice as high among Japanese men compared with Americans of both European and Japanese descent. Japanese men had significantly less atherosclerosis, as indicated by lower average intima-media thickness and coronary artery calcification. Among Japanese men, intima-media thickness values declined with rising omega-3 fatty acid levels, a phenomenon that was not observed in either American group. Continue Reading