Abstract 18775: Low Levels of Omega-3s In Hispanics Due to Genetic and Dietary Factors Can be Significantly Improved with a Highly Bioavailable Omega-3 Free-fatty Acid Formulation
Background: Hispanic Americans have low fish consumption compared to non-Hispanics. In addition to dietary intake, LC-PUFA plasma levels are affected by FADS1 gene polymorphisms. FADS1 genes code for desaturases that convert MC-PUFAs (linoleic, alpha-linoleic acid) to LC-PUFAs (arachidonic acid (AA), eicosapentaenoic acid (EPA)). The single nucleotide polymorphism (SNP), rs174546 in the FADS1 gene has previously been shown to be associated with variations in plasma EPA and AA and triglycerides levels . The present study evaluated the prevalence of the rs174546 SNP genotypes (CC, CT, TT) and corresponding plasma EPA, DHA and AA levels after treatment with an omega-3 free-fatty acid (FFA) formulation in a population of healthy Hispanic volunteers.
Methods: Forty six Hispanic participants in a statin pharmacokinetic study received 40 mg of simvastatin with and without a 4g daily dose of omega-3 FFA (primarily EPA and DHA ) for two weeks in a cross over study. Plasma samples were collected prior to and at the end-of-treatment in the omega-3 FFA arm for analysis of EPA, DHA, and AA.
Results: Prior to treatment the Hispanic population had a higher prevalence of TT homozygotes (41%) compared to CC homozygotes (24%) corresponding to significantly different levels of EPA (CC=18 ug/mL; CT=11 ug/mL; TT=7 ug/mL, p <0.0001) and AA (CC=266 ug/mL; CT=202 ug/mL; TT=167 ug/mL, p <0.0001) across genotypes. In response to Omega-3 FFA therapy a substantial increase in EPA was observed, with the largest percent increase in the TT genotype (TT:1054%, CT:573%, CC:253%, p<0.0001). Baseline plasma DHA levels were low suggesting comparable dietary fish intake and changes were similar across genotypes (CC:39%, CT:55%, TT:67%, p=0.2134).
Conclusion: In contrast to other ethnicities, the T allele in FADS1 polymorphism, rs174546 is the major allele in Hispanics and the TT genotype is associated with low levels of EPA. This difference in LC-PUFA levels can be exacerbated with low dietary omega-3 intake and may explain the high prevalence of hypertriglyceridemia in Hispanics. Our data suggests that treatment with a highly bioavailable omega-3 FFA may result in significant improvement in omega-3 levels in the Hispanic population.
- © 2012 by American Heart Association, Inc.