BACKGROUND: Although omega-3 polyunsaturated fatty acids are known to have beneficial effects on cardiovascular diseases, their prognostic value has not been studied prospectively in patients with acute myocardial infarction (AMI).

METHODS AND RESULTS: The plasma levels of phospholipids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) (% of total fatty acids), were measured in 508 patients (365 males; mean age, 63 years) with AMI. Clinical and biomarker predictors of all-cause and cardiovascular mortality were identified by stepwise Cox regression model. During a mean follow-up of 16.1 months, 36 (7.1%) patients died. After controlling for confounding variables, age (hazard ratio (HR): 1.09, P<0.001), renal insufficiency (HR: 2.84, P=0.01) and EPA level (HR: 0.29, P=0.004) were identified as independent predictors of all cause-mortality. When stratified by gender, age (HR: 1.08, P=0.001) and renal insufficiency (HR: 4.49, P=0.003) were predictors of all-cause-mortality in males, whereas EPA level (HR: 0.18, P=0.009) and angiotensin-converting enzyme inhibitor use (HR: 0.24, P=0.03) were identified as predictive of all-cause-mortality in females.

CONCLUSIONS: Lower plasma level of EPA, but not DHA, was an independent predictor for all-cause-mortality in patients with AMI, but this relationship was significant only in female patients.