Fish oil and vitamin D supplements don’t prevent atrial fibrillation

Contrary to previous reports, omega-3 fatty acids and vitamin D3 supplements do not prevent the development of atrial fibrillation (AFib), according to new findings presented at the American Heart Association’s Scientific Sessions 2020.

The authors pointed to previous studies that suggested omega-3 fatty acids found in fish oils and vitamin D may limit a person’s risk of developing AFib. To investigate these findings, they organized a placebo-controlled, randomized clinical trial of their own.

The VITAL Rhythm Trial lasted five years, from 2012 to 2017, and included more than 25,000 patients 50 years old and older. All patients had no history of AFib at the time of enrollment. The average patient age was 67 years old. While some patients were assigned fish oil and/or vitamin D3 supplements, others were simply given a placebo.

Overall, 3.6% of participants developed AFib during the trial’s follow-up period, and the researchers saw no statistically significant difference between patients taking the supplements and those who were given a placebo.

“With regards to clinical care, these results do not support using marine omega-3 fatty acids or vitamin D to prevent AFib,” lead author Christine M. Albert, MD, cardiology chair at the Smidt Heart Institute at Cedars-Sinai Medical Center in Los Angeles, said in a statement. “However, the results do provide reassurance that these supplements do not increase the overall risk of atrial fibrillation and appear to be generally safe for patients who are taking these supplements for other reasons.”

AHA Scientific Sessions is scheduled for Nov. 13-17, 2020. Additional information on this virtual event is available here.