Omega-3 Blood Levels and Stroke Risk: A Pooled and Harmonized Analysis of 183 291 Participants From 29 Prospective...

Area of Science:

• Cardiovascular Health
• Nutritional Science
• Epidemiology

Background:

• The impact of marine omega-3 polyunsaturated fatty acids (PUFAs) on stroke risk is not fully understood.
• Previous research has yielded inconclusive results regarding the protective effects of omega-3 fatty acids against stroke.

Purpose of the Study:

• To investigate the association between circulating and tissue levels of omega-3 PUFAs and the incidence of total, ischemic, and hemorrhagic stroke.
• To analyze data from multiple international prospective cohorts using a harmonized analytical approach.

Main Methods:

• Individual-level data from 29 international prospective cohorts were pooled.
• A prespecified protocol defined exposures, covariates, analytical methods, and outcomes.
• Multivariable-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated for omega-3 PUFA quintiles.

Main Results:

• Higher levels of eicosapentaenoic acid (EPA) were associated with a 17% lower risk of total stroke and an 18% lower risk of ischemic stroke.
• Higher levels of docosahexaenoic acid (DHA) were associated with a 12% lower risk of total stroke and a 14% lower risk of ischemic stroke.
• No significant association was found between EPA or DHA levels and the risk of hemorrhagic stroke.

Conclusions:

• Elevated omega-3 PUFA levels are associated with a reduced risk of total and ischemic stroke.
• Omega-3 PUFAs do not appear to influence the risk of hemorrhagic stroke.
• These associations remained consistent regardless of baseline atrial fibrillation or cardiovascular disease history.