(n-3) Fatty Acid Content of Red Blood Cells Does Not Predict Risk of Future Cardiovascular Events following an Acute Coronary Syndrome

Abstract

A reduced risk of fatal coronary artery disease has been associated with a high intake of (n-3) fatty acids (FA) and a direct cardioprotective effect by their incorporation into myocardial cells has been suggested. Based on these observations, the omega-3 index (eicosapentaenoic acid + docosahexaenoic acid in cell membranes of RBC expressed as percent of total FA) has been suggested as a new risk marker for cardiac death. In this study, our aim was to evaluate the omega-3 index as a prognostic risk marker following hospitalization with an acute coronary syndrome (ACS). The omega-3 index was measured at admission in 460 patients with an ACS as defined by Troponin-T (TnT) > or = 0.02 microg/L. During a 2-y follow-up, recurrent myocardial infarctions (MI) (defined as TnT > 0.05 microg/L with a typical MI presentation) and cardiac and all-cause mortality were registered. Cox regression analyses were used to relate the risk of new events to the quartiles of the omega-3 index at inclusion. After correction for age, sex, previous heart disease, hypertension, diabetes, smoking, high-sensitivity C-reactive protein, brain natriuretic peptide, creatinine, total cholesterol, HDL-cholesterol, triacylglycerol, homocysteine, BMI, and medication, there was no significant reduction in risk for all-cause mortality, cardiac death, or MI with increasing values of the index. In conclusion, we could not confirm the omega-3 index as a useful prognostic risk marker following an ACS.

Marine n-3 Polyunsaturated Fatty Acids in Adipose Tissue and the Risk of Acute Coronary Syndrome

“…21,23,46,47 Another case-control study, however, could not confirm this finding. 48 Red blood cells were not available for analysis in this study, so we were unable to provide further information on this issue.…”

Omega-3 fatty acid supplementation and cardiovascular disease

“…Thus, dietary supplementation with fi sh oil (C 20-22 3 PUFA), but not dietary fl axseed (ALA), signifi cantly increases cardiac muscle C 20-22 3 PUFA content. Such studies suggest that the omega-3 index may be a reasonable approach to assess cardiac 3 PUFA content and predict future CVD events ( 26,27 ). Sudden cardiac death (SCD), for example, is estimated to account for 50% of all deaths from CHD (28)(29)(30).…”

Lipid Biomarkers for Risk Assessment in Acute Coronary Syndromes

“…Several studies of measured EPA and DHA in patients with ACS have been reported, with mixed findings (Table 3). In one study of patients admitted for ACS (n = 460) and followed for 2 years, EPA and DHA (measured in whole blood) showed a trend between low concentrations of EPA and DHA and CV mortality; however, it was not significant [51]. A larger study (n = 1536) of patients enrolled in the TRIUMPH registry found that EPA and DHA (measured in erythrocyte membranes) added significantly to the GRACE score in predicting 2-year mortality [52].…”