Maki KC, et al. – This study was designed to update and further investigate the available randomized, controlled trial (RCT) data pertaining to long chain omega-3 polyunsaturated fatty acids (LC-OM3) supplementation and risk for cardiac death. The goal was also to propose testable hypotheses for the mixed results obtained in RCTs regarding supplemental LC–OM3 use and cardiac risk. Findings demonstrated that LC–OM3 supplementation was related to a modest attenuation in cardiac death.

Methods

• Researchers performed a literature search using PubMed and Ovid/Medline for RCTs assessing LC-OM3 supplements or pharmaceuticals with intervention periods of at least one year and reporting on the outcome of cardiac death.
• In addition, meta-analysis was employed to compare cumulative frequencies of cardiac death events between the LC-OM3 and control groups, including sensitivity and subset analyses.

Results

• The primary analysis included 14 RCTs (71,899 subjects).
• Findings revealed that in the LC-OM3 arms, 1613 cardiac deaths were recorded (4.48% of subjects), compared to 1746 cardiac deaths in the control groups (4.87% of subjects).
• Additionally, the pooled relative risk estimate showed a 8.0% (95% confidence interval 1.6%, 13.9%, p = 0.015) lower risk in the LC-OM3 arms vs. controls.
• Researchers also noted that subset analyses showed numerically larger effects (12.9% to 29.1% lower risks, all p < 0.05) in subsets of RCTs with EPA+DHA dosages >1 g/d and higher risk samples (secondary prevention, baseline mean or median triglycerides ≥150 mg/dL, low-density lipoprotein cholesterol ≥130 mg/dL, statin use <40% of subjects).
• As per data, heterogeneity was low (I² ≤ 15.5%, p > 0.05) for the primary and subset analyses.