The Omega-3 Index and relative risk for coronary heart disease mortality: Estimation from 10 cohort studies.
Level 3 - non-randomized controlled study
Meta-analysis of prospective observational cohort studies.
PubMed 28511049 · doi:10.1016/j.atherosclerosis.2017.05.007
What was done
Analyzed published data from 10 prospective cohort studies (derived from a prior 19-cohort meta-analysis) to calculate hazard ratios (HR) for fatal coronary heart disease (CHD) per 1-standard deviation increase in the Omega-3 Index (erythrocyte EPA + DHA as a percentage of total fatty acids) and evaluate previously proposed clinical cut-points (<4% and 8%–12%).
What was found
The pooled mean (SD) Omega-3 Index across the 10 cohorts was 6.1% (2.1%). Each 1-SD increase in the Omega-3 Index was associated with a lower risk of fatal CHD (HR 0.85; 95% CI, 0.80–0.91). Median levels for quintiles 1 and 5 were 4.2% and 8.3%, respectively, corresponding to an estimated ~30% reduction in fatal CHD risk between an Omega-3 Index of 4% versus 8%.
Why it matters
Provides quantitative observational support for clinical cut-points (<4% higher risk, >8% lower risk) when using the Omega-3 Index as a biomarker for coronary heart disease mortality risk.
Limits
Relies entirely on observational cohort data, precluding causal inference. Only 10 of the original 19 cohorts had available data for this specific metric. Participant counts, demographic characteristics, follow-up durations, and adjustments for residual confounding were not reported in the abstract.
Cited by
- context A high omega-3 index is associated with a 5-year increased life expectancy and a 90% reduction in sudden cardiac death.