Omega-3 Index linked to CVD risk factors in adolescent boys
MedWire News: The Omega-3 Index, a measure of long-chain omega-3 fats in red blood cell (RBC) membranes, is associated with reduced cardiovascular disease (CVD) risk in adolescent boys, according to study results.
"Our results demonstrate a significant and independent association between Omega-3 Index and total and high-density lipoprotein (HDL) cholesterol, as well as blood pressure, in Australian adolescent boys," report Therese O'Sullivan (University of Western Australia, West Perth) and colleagues in the journal Lipids.
The researchers also say that in male and female adolescents there is a significant association between a higher Omega-3 Index and healthier food consumption.
O'Sullivan's team determined the Omega-3 Index in 1301 adolescent (aged 13-15 years) participants from the Western Australian Pregnancy (Raine) Cohort. They then analyzed the data for associations between individuals' Omega-3 Index and CV and metabolic risk factors.
Overall, the mean Omega-3 Index was 4.9%, with 15.6% of adolescents being in the high coronary heart disease (CHD) mortality risk category (Omega-3 Index <4%), 84.0% in the intermediate risk category (4-8%), and 0.4% in the low risk category (>8%).
In boys, a higher Omega-3 Index was significantly associated with increased levels of total and HDL cholesterol, and lower diastolic blood pressure, insulin, and homeostasis model assessment for insulin resistance (HOMA-IR). However, there were no significant associations observed in girls.
Commenting on these gender differences, the researchers suggest that sex hormones might play a role modifying the omega-3 content of tissues, possibly by altering expression of enzymes in the liver, while also "contributing to gender-specific pathophysiological differences in CV and metabolic disease."
Finally, O'Sullivan et al found that increases in the Omega-3 Index were associated with healthier eating, increases in the dietary intake of eicosapentaenoic and docosahexaenoic acids, proteins, and total omega-3 fats in adolescent boys and girls.
They therefore suggest that dietary factors may also play a role in altering the fatty acid content of RBC membranes by affecting the Omega-3 Index which, in adults, has been proposed to predict CHD mortality.
The researchers conclude that the "predictability of the Index for the risk of CVD later in life warrants further investigation in the adolescent population."
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By Nikki Withers