Omega-3 Index reflects diet, vascular risk in adolescents
MedWire News: The amount of long-chain omega-3 fatty acids in erythrocyte membranes is associated with diet and cardiovascular risk in adolescents, study findings show.
The authors of the study, writing in the journal Lipids, suggest that the "Omega-3 Index" represents a simple and useful tool for predicting the risk for cardiovascular disease in young adults.
The Index - which reflects the proportion of eicosapentaenoic acid and docosahexaenoic acid in red blood cell membranes as a percentage of total fatty acids - is already known to predict heart disease mortality in adults.
In this study, Therese O'Sullivan (University of Western Australia, West Perth) and colleagues determined the Omega-3 Index for 1301 adolescents aged 13-15 years who were participating in the Western Australia Pregnancy (Raine) Cohort.
The mean Omega-3 Index was 4.90% and ranged from 1.41 to 8.42%, the authors report.
Using published risk categories, 15.6% of participants were considered high-risk, 84.0% as intermediate-risk, and 0.4% as low-risk for cardiovascular disease.
After adjusting for potential confounders, the Index was positively associated with levels of total cholesterol and high-density lipoprotein cholesterol, as well as with dietary intake of fish/seafood, wholegrain foods, and vegetables, and inversely associated with intake of soft drinks and crisps.
The Index as a continuous variable also showed a significant positive association with "healthy eating pattern" scores and a significant negative association with "Western eating pattern" scores.
Finally, daily intake of eicosapentaenoic and docosahexaenoic acids was positively correlated with the Omega-3 index.
O'Sullivan and colleagues say that the Omega-3 Index has been proposed as a "physiologically relevant, modifiable, and independent risk factor" for cardiovascular disease.
"Although the Omega-3 Index did not demonstrate a statistically significant association with the cholesterol ratio, it is considered to be a risk factor in its own right and has not been shown to mediate through effects on traditional risk factors," they write.
"Therefore the Index may still be useful in the prediction of cardiovascular disease later in life, and our results support further long-term investigation of this concept."
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By Joanna Lyford