Fish Oil Supplements Associated with Risk of Atrial Fibrillation

Many vitamins and supplements are readily available over the counter for patient use. Understanding the effects of supplements on healthcare can impact and inform physician practices for more effective patient care. In a recent publication in the European Journal of Preventative Cardiology, clinicians found that habitual intake of fish oil supplements may be associated with a higher rate of atrial fibrillation regardless of patient risk.

Researchers in this study used data from the UK Biobank on 468,665 patients who initially had no atrial fibrillation (AF). Patients were followed up for approximately 11.1 years.

On average, the incidence rate of AF in fish oil users was approximately 6.2%, while nonusers had a rate of 5.2%. In addition to looking at the data overall, investigators divided the analysis based on the risk of AF. Among all three risk levels — low, intermediate, and high — fish oil users still had a higher risk of AF.

For low AF risk patients, fish oil increased the risk of developing AF by 0.7%. As AF risk worsened, so did the impact of fish oil. For patients at intermediate AF risk, those who used fish oil habitually were 1% more likely to develop AF. Finally, for those at high risk of AF, the difference was 1.7%.

Despite the data collected, researchers concluded that the results only applied to those who did not have cardiovascular disease at baseline. For those who did have cardiovascular disease at baseline the impact of fish oil supplements was inconsistent.

“The general population should be informed of the potential AF risks with fish oil supplementation, and the physicians should balance the risk–benefit ratio with fish oil supplementation given that the cardiovascular benefit of fish oil supplementation is undetermined in prior clinical trials,” stated researchers in the publication.

Researchers in the study implied that additional research must be conducted on the effects of fish oil supplements on cardiovascular health. While supplements may be a tool to enhance nutrition, they are not always the best treatment method. Clinicians should consider informing patients about the risk of supplements and record any supplement usage in the patient’s chart.