Coffee may reduce risk of atrial fibrillation, study suggests

A small JAMA trial of 200 adults with atrial fibrillation found that those who continued about one cup of caffeinated coffee daily had fewer recurrent AFib or atrial flutter episodes over six months than those who avoided caffeine, though researchers say the findings are preliminary and require larger trials.

Researchers report results from a small randomized study testing whether habitual coffee intake affects recurrence of atrial fibrillation. The trial enrolled 200 adults with AFib who were scheduled for cardioversion and followed them for six months. Participants typically drank about one cup of caffeinated coffee per day at baseline and were randomized to either continue at least one cup daily or avoid all caffeine. Atrial fibrillation is a common irregular, often rapid heart rhythm that can raise risks such as stroke or heart failure. Key findings: - The study published in JAMA enrolled 200 adults with AFib who were followed for six months after randomization. - At baseline participants reported about one cup of caffeinated coffee daily; half were assigned to continue at least one cup per day and half to avoid caffeine. - During the six-month period, 47% of the coffee group had recurrent AFib or atrial flutter episodes lasting more than 30 seconds, compared with 64% of the no-caffeine group, a reported 39% lower risk in the coffee group. - About half of participants were taking medications for AFib and continued those treatments during the study. - The trial was small and limited to roughly one cup per day, so applicability to higher caffeine intake or other caffeinated beverages is unclear. Summary: The trial observed fewer recurrent arrhythmia episodes among participants who continued about one cup of caffeinated coffee daily compared with those who avoided caffeine. Investigators and clinicians describe the results as preliminary and note that larger, more diverse trials are needed to confirm whether coffee or compounds in coffee influence AFib recurrence. Undetermined at this time whether these findings apply to higher caffeine amounts, different populations, or other caffeinated drinks.