Clinical correlates and heritability of erythrocyte eicosapentaenoic and docosahexaenoic acid content in the Framingham Heart Study.
Level 4 - case-series / case-control
Cross-sectional observational and heritability analysis within established cohorts
PubMed 22727409 · doi:10.1016/j.atherosclerosis.2012.05.030
What was done
Red blood cell fatty acid composition was analyzed by gas chromatography in 3,196 samples collected between 2005 and 2008 from participants in the Framingham Heart Study (Offspring cohort Examination 8 and Omni cohort Examination 3). Multivariable regression models were used to evaluate clinical correlates of the omega-3 index (erythrocyte EPA plus DHA percentage) and to estimate its heritability.
What was found
The mean (SD) omega-3 index was 5.6% (1.7%). The fully adjusted multivariable model explained 73% of total variability, with major contributions from dietary EPA plus DHA intake (25%), heritability (24%), and fish oil supplementation (15%). Significant direct correlates were age, female sex, higher education, fish oil supplementation, dietary EPA plus DHA intake, aspirin use, lipid pharmacotherapy, and LDL-cholesterol. Significant inverse correlates were Offspring cohort membership, heart rate, waist girth, triglycerides, and smoking.
Why it matters
This study quantifies the primary drivers of omega-3 index variability in a community population, showing that genetic heritability accounts for roughly a quarter of the variance alongside dietary and supplemental intake.
Limits
The study is cross-sectional, precluding causal inferences. The abstract does not report numerical effect sizes, regression coefficients, or confidence intervals for the individual clinical correlates.
Cited by
- supports The average American has an Omega-3 Index of approximately 5% of total red blood cell membrane fatty acids.