Circulating oleic acid levels are related to greater risks of cardiovascular events and all-cause mortality: The Multi-Ethnic Study of Atherosclerosis

Background: Limited evidence has suggested that circulating levels of the omega-9 fatty acid, oleic acid, may be related to greater risks of adverse cardiovascular outcomes. Objective: We aimed to determine whether plasma oleic acid may be independently associated with clinical and subclinical cardiovascular disease (CVD) and all-cause mortality in a large multiethnic cohort. Methods: Plasma fatty acids were measured by gas chromatography–flame ionization in 6568 participants of the Multi-Ethnic Study of Atherosclerosis. The presence of coronary artery calcium (CAC) and aortic valve calcification (AVC) was determined by computed tomography, and carotid plaque was assessed by ultrasound. Incident CVD was defined as myocardial infarction, fatal coronary heart disease, resuscitated cardiac arrest, stroke, or stroke death. Heart failure (HF) was adjudicated from clinical records. Relative risk regression estimated plasma oleic acid-related rate ratios for prevalent CAC, AVC, and carotid plaque. Cox regression estimated hazard ratios (HRs) for CVD, HF, and all-cause mortality over a median 13-year follow-up. Results: Individuals in top quartiles of oleic acid showed greater rate ratios of CAC, AVC, and carotid plaque (all P <.001), but associations were rendered nonsignificant after adjustment for other risk factors. By contrast, those in top quartiles of plasma oleic acid showed significantly greater risks of incident HF (HR: 2.03; P <.001), CVD (HR: 1.41; P =.008), and all-cause mortality (HR: 1.55; P <.001) than those in referent quartiles independent of typical risk factors as well as plasma omega-3 fatty acid levels. Conclusions: Plasma oleic acid appears to be a risk factor for CVD events and all-cause mortality independent of typical risk factors and plasma omega-3 fatty acids. Additional studies are warranted for confirmation and to further examine whether plasma oleic acid directly contributes to, or serves as a marker of, disease pathogenesis. These findings should not be extrapolated to dietary oleic acid intake.