Drinking caffeinated coffee is safe for individuals diagnosed with atrial fibrillation (A-fib) and may even help protect against the recurrence of this heart disorder, according to a recent study. Atrial fibrillation affects over 10 million Americans, leading to symptoms such as heart palpitations, dizziness, and breathlessness, as well as serious complications like heart failure, blood clots, and stroke.
For years, healthcare professionals have debated the impact of caffeine on atrial fibrillation. Given that caffeine can elevate heart rate and blood pressure, there have been concerns about whether it could potentially trigger episodes of A-fib. “There is no standard advice for atrial fibrillation and caffeine,” stated Dr. Gregory Marcus, a cardiologist and professor of medicine at the University of California, San Francisco. He led the DECAF (Does Eliminating Coffee Avoid Fibrillation?) study, which aims to clarify this issue.
The findings from the DECAF study were presented at the annual American Heart Association conference held in New Orleans and published in the Journal of the American Medical Association (JAMA). The study involved 200 older adults from Australia, Canada, and the United States, all of whom had a history of irregular heart rhythms. The average age of participants was 70, with one-third being women. The study lasted six months and randomized participants into two groups: one that eliminated caffeine and another that consumed at least one cup of coffee daily.
During the trial, participants reported their coffee and caffeinated beverage intake during scheduled telehealth check-ins. Researchers used electrocardiograms (ECGs) and wearable heart monitors to track incidents of recurrent A-fib. Notably, the study found that those who continued drinking coffee had a lower incidence of A-fib episodes compared to those who abstained.
Results showed that 56% of participants experienced a recurrent episode of atrial flutter during the study. However, only 47% of those in the coffee-drinking group faced recurrence, compared to 64% in the caffeine-free group. This suggests that consuming one cup of coffee daily may offer protective effects against A-fib recurrence.
Dr. Marcus was pleasantly surprised by the substantial protective effect of caffeinated coffee on A-fib recurrence. His findings are consistent with previous observational studies indicating that coffee drinkers may have a lower risk of developing atrial fibrillation.
Dr. Johanna Contreras, a cardiologist at Mount Sinai Fuster Heart Hospital in New York, emphasized that the most significant takeaway from the study is that drinking a cup of coffee a day is deemed safe for those with A-fib. However, she noted that individual reactions to caffeine may vary. “There’s not a hard-and-fast rule. Not everyone has the same reaction to caffeine,” she explained.
While the DECAF study provides valuable insights, it also has limitations. It did not track the effects of other caffeinated beverages or examine participants' exercise habits and dietary differences. Dr. Marcus suggested that individuals who drink coffee may also engage in more physical activity, which could influence heart health.
The study indicated that moderate coffee consumption—specifically one cup per day—appears to be beneficial. However, excessive consumption, such as six or seven cups along with energy drinks, could have adverse effects. “Moderation is key,” Contreras cautioned.
While the exact reasons for the protective effects of coffee on A-fib recurrence remain unclear, Dr. Marcus hypothesized that an anti-inflammatory compound in coffee, rather than caffeine itself, might play a role. It’s also possible that caffeine stimulates the body’s adrenaline response, which could help prevent A-fib episodes that often occur during relaxed states.
It is important to note that the study participants were not currently experiencing A-fib episodes. Therefore, the findings may not apply to individuals with unmanaged A-fib, as caffeine might exacerbate symptoms during an episode.
For individuals living with atrial fibrillation who are regular coffee drinkers, this study provides reassurance. As Dr. Contreras noted, “this shows you can have a cup of coffee in the morning and be OK if you have A-fib.” The DECAF study underscores the potential benefits of moderate caffeinated coffee consumption for those managing atrial fibrillation.