Coronary diseases: fewer deaths thanks to the anti-inflammatory action of Omega-3

Omega-3 can reduce the probability of death from heart disorders, and beyond. Daily intake of Omega-3 EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid) by patients with coronary diseases is associated with a decreased risk of cardiovascular events, sudden cardiac death, and death from other causes. 

This is reported by a meta-analysis study, i.e., an analysis of data obtained from multiple independent studies, conducted by researchers at Nanjing University (China), and recently published in the journal Nutrition, Metabolism and Cardiovascular Diseases.

Omega-3 and cardiovascular risk

In the last century, a Danish researcher noted the low frequency of deaths from heart attack among Greenland inhabitants compared to those in Denmark. Comparing their diets, he noticed the Danish diet was rich in meat, while the Eskimos’ diet was mainly fish-based. The relationship between consumption of fish rich in Omega-3 and cardiovascular protection was later confirmed by numerous studies.

Today, the mechanisms through which Omega-3 exert their protective action are also known. EPA and DHA fluidify membranes and stimulate relaxation of the endothelium, the tissue lining blood vessels, lowering blood pressure.

They regulate platelet aggregation and inflammation, limiting the formation of atherosclerotic plaques. Additionally, Omega-3 reduce the heart’s susceptibility to arrhythmia and lower plasma triglyceride levels.

Omega-3 reduce the risk of death

The meta-analysis considered 14 clinical studies of different durations, from 3 months to 4 years, involving a large number of participants. Of these, 16,318 randomly chosen participants received a placebo, while 16,338 took supplements of DHA, EPA, or both. Participants included in the study had suffered heart attacks or ischemia, or suffered from heart failure, angina, atherosclerosis, or coronary diseases. Among those who took supplements, researchers observed a trend toward reduction of major cardiovascular events (heart attack, stroke, ischemia), not evident in control subjects. Separate analyses in patients with coronary atherosclerosis revealed a 51% reduction in risk of cardiovascular events in those given Omega-3 compared to controls. Furthermore, supplementation with high doses, more than one gram per day, of Omega-3 was associated with a 22% reduction in risk of heart attack, stroke, or ischemia. Among those who received supplements, the probability of dying from heart problems was 13% lower, and sudden cardiac death 14% lower, compared to control subjects. Surprisingly, among people who took Omega-3, the risk of death from non-cardiovascular causes was also 8% lower compared to those who received placebo.

Positive results but to be confirmed

The results of this meta-analysis indicate an association between Omega-3 and reduced mortality from heart problems and beyond in patients with coronary diseases. This effect is due to the combined protective actions of EPA and DHA on lipid metabolism, blood pressure, and vascular and cardiac functions. However, the role of dietary Omega-3 supplementation in patients with coronary disease still needs to be further studied with additional clinical trials.

Source: 

Wen YT, Dai JH, Gao Q. “Effects of Omega-3 fatty acid on major cardiovascular events and mortality in patients with coronary heart disease: A meta-analysis of randomized controlled trials” Nutr Metab Cardiovasc Dis. 2013 Dec 25. pii: S0939-4753(13)00308-6.

 doi: 10.1016/j.numecd.2013.12.004