The risk reduction in people with elevated triglycerides or LDL cholesterol was even higher at 17%, the scientists at Midwest Biomedical Research and the Johns Hopkins University School of Medicine wrote in the Journal of Clinical Lipidology.
According to the Centers for Disease Control and Prevention (CDC), cardiac death accounts for about two-thirds of all cardiovascular deaths in the US and 42% worldwide each year.
“It is important to note that these results are consistent with the conclusions of the American Heart Association’s recent Science Advisory that EPA and DHA omega-3 treatment are ‘appropriate’ for secondary prevention of coronary heart disease and sudden death.” Said Dr. Kevin Maki of Midwest Biomedical Research, the lead author of the study.
“A notable feature of omega-3 supplementation with EPA and DHA is the low risk associated with their use. Because of the low risk of side effects, even a modest benefit makes clinical sense. “
Improved benefits in North America
Independently commenting on the meta-analysis, Bruce Holub, PhD, University of Guelph Emeritus Professor, said, “This updated review shows that the majority of adults (with no or with clinical evidence of atherosclerotic cardiovascular disease) are likely to receive one significant protection against sudden cardiac death through EPA / DHA supplementation with appropriate intake.
“The benefits of such a supplement are increased in regions where dietary EPA / DHA from fish / seafood is low, such as in North America (where the average intake is only 110-150 mg / person / day).”
A 2017 meta-analysis of 18 RCTs, also funded by GOED, found that EPA and DHA were associated with statistically significant reductions in the risk of coronary heart disease in higher-risk populations, including a 16% reduction in patients with high triglycerides and 14% in those with high LDL cholesterol (Mayo Clinic Proceedings, Vol. 92, pp. 15-29). Image: © iStock / winlyrung
The new meta-analysis is reportedly the first to include cardiac death (also known as “coronary mortality”) as the primary endpoint and the most comprehensive review of the evidence to date. It was funded by the Global Organization for EPA and DHA Omega-3 (GOED), but the organization was not involved in framing or interpreting the results.
Dr. Harry Rice, Vice President of Regulatory and Scientific Affairs at GOED, welcomed the study’s conclusions, saying, “This study is important as it examines the effects of omega-3s on a specific outcome in coronary artery disease. .
“A number of studies in recent years have questioned the benefits of omega-3s in cardiovascular disease. However, to understand the role of omega-3s in the cardiovascular system, research needs to focus on a specific disease, rather than all cardiovascular outcomes combined. This is an important nuance that this meta-analysis can clarify. “
Systematic reviews and meta-analyzes are at the top of the pyramid of scientific evidence, making it one of the strongest forms of evidence.
In the new meta-analysis, data from 14 randomized, controlled studies (RCTs) with a total of 71,899 people were combined. The RCTs reviewed were longer than six months and examined cardiac death as the primary outcome, comparing the frequency of cardiac death events between the omega-3 group and the control group. The authors did not investigate the effects of EPA and DHA consumption by fish on the risk of cardiac death, as no randomized, controlled studies exist. However, data from observational studies on EPA and DHA from fish also support a risk reduction benefit.
The results showed that in addition to the statistically significant 8% reduction in the risk of cardiac death for consumption of EPA and DHA omega-3 fatty acids, the risk of cardiac death in people using higher doses greater than 1 in general by almost 30% decreased grams of EPA and DHA per day (see table below).
None of the studies were conducted to elucidate the mechanism of action – how omega-3 fatty acids can reduce the risk of cardiac death – but Maki et al. Finding that dosages in excess of 1 gram of EPA + DHA per day may be required to produce clinically relevant changes in some pathways, such as: B. Effects on inflammation and thrombosis. “
The authors concluded: “These results suggest that additional research is required to further evaluate the potential risk reduction [long chain omega-3] Supplement at higher dosages and in samples with higher risk. Future RCTs should include the assessment of biomarkers with omega-3 status at baseline and during treatment and test specific hypotheses about the mechanisms by which benefits might be obtained. Four RCTs to assess CVD event risk with [long chain omega-3] The interventions are ongoing and should provide additional information helpful to guide the clinical application of [long chain omega-3] Supplement or drug therapy. “
Source: Journal of Clinical Lipidology
Published online before going to press, doi: 10.1016 / j.jacl.2017.07.010
“Use of Additional Long-Chain Omega-3 Fatty Acids and Risk of Cardiac Death: An Updated Meta-Analysis and Review of Research Gaps”
Authors: KC Maki et al.