A newly published meta-analysis has suggested that supplementation with omega-3 fatty acids does not increase the risk of atrial fibrillation (AF).
The research, led by researchers from the Fatty Acid Research Institute (FARI) and published in Circulation: Arrhythmia and Electrophysiology, contradicts previous meta-analyses that suggested omega-3 supplements may increase the risk of AF.
What the research found
The study analysed data from 35 randomised controlled trials involving 114,592 participants — more than four times the number of studies included in previous meta-analyses.
The researchers also incorporated unpublished trial data as well as previously unavailable safety information to provide the most comprehensive assessment of AF risk to date.
They found that low-dose omega-3 supplementation (which is classed as less than 1500 mg/day EPA+DHA) was not associated with an increased risk of AF, even among individuals at elevated cardiovascular risk.
In contrast, only in the setting of high-dose omega-3 therapy (>1500 mg/day, typically prescription-strength formulations) used in patients with established cardiovascular disease was AF risk modestly increased.
"Our findings show that the relationship between omega-3s and atrial fibrillation is much more nuanced than previous headlines suggested," said Dr William S. Harris, President of the Fatty Acid Research Institute (FARI) and senior author on the study.
For the vast majority of people taking nutritional doses of omega-3s, these data should provide reassurance that there is no meaningful increase in atrial fibrillation risk.
In recent years, several meta-analyses have suggested that omega-3 supplements may increase the risk of atrial fibrillation (AF).
However, these analyses included no more than eight randomised trials, predominantly focused on cardiovascular outcomes.
They also overlooked numerous eligible trials that had available but unpublished data on AF.
Translating the findings into a clinical context
The research team emphasised that even among high-risk cardiovascular patients receiving prescription-level omega-3 doses, the observed increase in AF should be weighed against the well-established cardiovascular benefits demonstrated in major clinical trials.
For example, previous studies of high-dose EPA have shown reductions in heart attacks, stroke and other major cardiovascular events that substantially outweigh the small increase in atrial fibrillation risk.
"The decision to take or discontinue omega-3 supplements should be a discussion between a patient and his/her healthcare provider," added Harris.
What this study does is provide clinicians with better guidance on which patients may benefit from closer monitoring when using high-dose omega-3 therapies while reassuring consumers that it is safe to consume omega-3 fatty acids from foods and dietary supplements.
The findings also reinforce an important distinction between nutritional omega-3 supplementation (typically 500-1500 mg/day) and pharmacological omega-3 therapy (typically 2-4 grams/day), which is prescribed for individuals with elevated triglycerides or established cardiovascular disease.
The authors also emphasise that AF risk profiles should be evaluated separately for each category, as nutritional doses do not carry the same clinical implications as higher pharmacological doses.
