Abstract MP44: Biomarker Measures of Fish-Derived Omega-3 Fatty Acids and J-Point Elevation in the Atherosclerosis Risk in Communities (ARIC) Study
Background: Higher intake of fish-derived omega-3 polyunsaturated fatty acids (PUFAs) has been associated with lower incidence of Sudden Cardiac Death (SCD), but the exact mechanisms underlying this association are unconfirmed. Early ventricular repolarization characterized by an elevation of the QRS-ST junction (J-Point) in the surface ECG has been associated with idiopathic ventricular fibrillation, the most common cause of SCD. We aimed to study the association of fish-derived PUFAs in plasma with the prevalence of J-Point elevation.
Methods: We conducted a cross-sectional analysis of participants aged 45-64 (45.7% male, 100% whites) from the Minnesota Field Center of the Atherosclerosis Risk in Communities (ARIC) Study. Participants were excluded if they did not have an ECG, had a QRS duration ≥ 120 ms, were taking Class I or Class III antiarrhythmic agents, or had prevalent cardiovascular disease. Fish-derived PUFAs were measured in plasma phospholipids as a percentage of total fatty acids, categorized into quartiles, and logistic regression was used to estimate the odds of J-Point Elevation, defined as elevation of greater than 100 microvolts in at least two contiguous leads. Models were adjusted for potential confounders and tests of linear trend were conducted by assigning the median values for each exposure category and modeling as a continuous variable.
Results: Among 3,330 eligible individuals, 126 presented J-Point elevation. Median fish-derived fatty acid percentage was 3.2% (range: 0.7-12.2). Using multivariable analyses, plasma measures of fish-derived omega-3 PUFAs were linearly associated with the log odds of J-Point elevation with increasing fatty acid percentages associated with lower odds of J-Point elevation (see Table).
Conclusions: In this population, higher plasma levels of fish-derived PUFAs were inversely associated with J-Point elevation. Fish-derived PUFAs could reduce risk of SCD through decreased prevalence of early repolarization.
- © 2013 by American Heart Association, Inc.