Blood levels of long-chain n-3 fatty acids and the risk of sudden death.
Level 4 - case-series / case-control
Prospective nested case-control study
PubMed 11948270 · doi:10.1056/NEJMoa012918
What was done
Prospective, nested case-control analysis of apparently healthy men followed for up to 17 years in the Physicians' Health Study. Gas-liquid chromatography measured baseline blood fatty-acid composition in 94 men whose first manifestation of cardiovascular disease was sudden death and in 184 controls matched for age and smoking status.
What was found
Baseline blood levels of long-chain n-3 fatty acids were inversely associated with the risk of sudden death before adjustment (P for trend = 0.004) and after adjustment for potential confounders (P for trend = 0.007). Compared with the lowest quartile, the adjusted relative risk of sudden death was 0.28 (95% CI, 0.09 to 0.87) for the third quartile and 0.19 (95% CI, 0.05 to 0.71) for the fourth quartile.
Why it matters
This study shows that circulating biomarkers of long-chain n-3 fatty acids from fish are strongly associated with a lower risk of sudden death in primary prevention, extending prior findings from post-myocardial infarction cohorts.
Limits
The study is observational and cannot establish causality. Blood fatty acids were measured only at baseline. The cohort included only male physicians, limiting generalizability to women and other populations. Case numbers were relatively small with 94 sudden death events.
Cited by
- partial Having a high omega-3 index is associated with a 90% lower risk of sudden cardiac death.