(P22-112-20) Circulating Marine and Vegetable Omega-3 at the Time of ST-Segment Elevation Myocardial Infarction and Incident Hard Clinical Endpoints

Objectives: Dietary marine omega-3 eicosapentaenoic acid (EPA) is readily incorporated into cardiac cell membranes, partially replacing the omega-6 arachidonic acid (AA). Blood omega-3 is an objective marker of their intake over the last days. Increasing blood EPA at the time of a ST-segment elevation myocardial infarction (STEMI) relates to a smaller infarct size and preserved long-term left ventricular ejection fraction. We explored whether blood EPA at the time of STEMI also relates to a lower incidence of hard clinical endpoints. We also explored whether blood alpha-linolenic acid (ALA, the vegetable omega-3) modulates such association.

Methods: We prospectively included 944 consecutive patients treated with primary percutaneous coronary intervention in a single tertiary referral hospital. We determined fatty acids in serum phosphatidylcholine (PC) at 12 hours of evolution. The primary outcomes were cardiovascular disease-related hospital readmission and all-cause mortality after 3 years of follow-up. We constructed multivariable Cox proportional hazards models, calculating risk estimates as hazard ratios (HR).

Results: The mean age of the cohort was 61 years and 209 (22.1%) were women. During follow-up, 130 patients (13.8%) were readmitted for cardiovascular disease, and 108 (11.4%) died. After adjustment for known clinical predictors, multivariate analysis showed that EPA in serum PC at the time of STEMI inversely related to incident hospital readmission (HR, 0.74; 95% CI, 0.56-0.96; P=0.024, for a 1 SD increase). Further adjustment for serum PC AA and ALA did not change the association. EPA in serum PC was found to be unrelated to 3-y total mortality. However, after including serum PC proportions of AA and ALA into the model, we observed a significantly decreased risk of mortality for ALA (HR, 0.65; 95% CI, 0.44-0.96; P=0.030, for a 1 SD increase).

Conclusions: Increasing proportions of EPA and ALA in serum PC at the time of STEMI inversely relate to 3-y cardiovascular disease-hospital readmission and all-cause mortality, respectively. Dietary EPA and ALA act synergistically and are partners rather than competitors in improving prognosis in case of a STEMI.

Funding Sources: Instituto de Salud Carlos III, Spain; California Walnut Commission