A Daily Cup of Coffee May Reduce the Risk of Atrial Fibrillation Recurrence by 39%

Atrial fibrillation (AFib) is a common cardiovascular condition that affects an estimated 37 million people worldwide. Various factors contribute to the development of AFib, including genetics, age, an unhealthy diet, and uncontrolled blood pressure. As a result, many patients are advised to limit or avoid certain foods and beverages—especially caffeine, sugar, alcohol, and high-sodium foods—to help reduce their risk. 

However, a recent randomized trial suggests that drinking one cup of caffeinated coffee each day may lower the risk of recurrent AFib by up to 39%, challenging long-standing dietary recommendations for these patients.

Why Focus on Caffeinated Coffee?

In this study, researchers recruited 200 adults with persistent AFib who were also regular coffee drinkers. Participants were randomly assigned to either consume at least one cup of caffeinated coffee daily or completely abstain from caffeine over a six-month period. 

“Caffeinated coffee is the most commonly consumed beverage in the U.S., and the majority of studies examining its health effects have been observational,” said Gregory M. Marcus, MD, MAS, a professor of medicine at the University of California, San Francisco, and the lead author of the study. “Despite the lack of strong evidence recommending that patients avoid it, those with atrial fibrillation are often instructed to stop consuming caffeine.”

One Cup of Coffee a Day Linked to 39% Lower AFib Recurrence

At the end of the six-month trial, participants who consumed one cup of caffeinated coffee daily experienced a 39% reduction in AFib recurrence compared to those who abstained. 

“This is the first long-term randomized trial of caffeinated coffee,” Marcus explained. “A randomized study design is the best method for inferring actual causal effects. These findings should reassure our atrial fibrillation patients who enjoy caffeinated coffee and provide data for clinicians who have previously advised against it.” 

Marcus also noted that this trial opens the door for future research to explore whether caffeinated coffee could play a protective role in AFib management.

How Might Caffeine Help Protect Against AFib?

Several biological mechanisms may explain why caffeinated coffee could reduce AFib risk: 

• Autonomic Effects: AFib often arises during periods of heightened vagal tone (e.g., during sleep or after heavy meals). Mild stimulation of the sympathetic nervous system by caffeine may counteract this effect.  
• Blood Pressure Benefits: While caffeine is sometimes linked to higher blood pressure, long-term coffee consumption appears to have a mild diuretic effect, which may help reduce blood pressure over time—a known protective factor against AFib.
• Electrophysiologic Effects: Animal studies suggest that caffeine may prolong the electrical recovery phase (refractoriness) of the left atrium, theoretically reducing susceptibility to AFib.
• Increased Physical Activity: In the CRAVE trial, caffeinated coffee intake was associated with an average increase of 1,000 steps per day. More physical activity is known to reduce AFib recurrences.
• Anti-inflammatory Properties: Coffee contains numerous bioactive compounds with anti-inflammatory effects. Inflammation is a key driver of AFib.

Expert Opinions: Reassuring Findings for Patients and Clinicians

Dr. Nikhil Warrier, a cardiac electrophysiologist and medical director at MemorialCare Heart & Vascular Institute, noted that these findings align with emerging evidence suggesting that moderate caffeine intake does not increase AFib risk. 

“Our current guidance is that caffeine within normal limits is not associated with added risk,” Warrier said. “This randomized trial supports that approach and helps us move away from advising patients to completely avoid coffee.” 

He emphasized that AFib is heavily influenced by lifestyle factors such as weight control, sleep quality, alcohol intake, and regular exercise. Understanding how everyday habits affect AFib helps patients take an active role in improving their long-term outcomes.

Areas Requiring Further Research

Dr. Renato Apolito, medical director at Hackensack Meridian Jersey Shore University Medical Center, also found the results encouraging but highlighted areas needing further investigation. 

“Many cardiologists traditionally advised patients with AFib to limit caffeine intake, but this was largely theoretical,” Apolito said. “The DECAF trial suggests that a minimal daily amount of coffee may be safe and possibly beneficial.” 

He noted that the study only included individuals who were already coffee drinkers and evaluated only one cup of caffeinated coffee per day. Future research should explore: 

• Whether higher amounts of coffee provide similar or greater benefits.
• Whether other caffeinated beverages (e.g., tea, energy drinks, cola) have the same effect.
• Whether the benefits extend to individuals who did not drink coffee before their AFib diagnosis.

Source

MedicalNewsToday