Is coffee proarrhythmic? New data suggest otherwise

For adults treated for persistent atrial fibrillation (AF), drinking a cup of coffee every day does not trigger AF recurrence or atrial flutter and even appears to reduce its incidence, according to the DECAF trial.

Compared with abstinence, coffee drinking was associated with fewer recurrent AF or ≥30-sec atrial flutter events over 6 months of follow-up (47 percent vs 64 percent), representing a 39-percent risk reduction (hazard ratio [HR], 0.61, 95 percent confidence interval [CI], 0.42–0.89; p=0.01). [JAMA 2025;doi:10.1001/jama.2025.21056]

The observed benefit with coffee drinking persisted in an analysis that looked at recurrent AF events alone (HR, 0.62, 95 percent CI, 0.43–0.91; p=0.01).

Adverse events did not significantly differ between the coffee drinking and abstinence arms, including emergency department visits (13 vs 16) and hospitalizations (23 vs 21).

These findings challenge the traditional assumption that coffee promotes atrial arrhythmogenesis but agree with some observational data suggesting a neutral or beneficial association between coffee and AF, the investigators said. [JAMA Intern Med 2021;181:1185-1193; Eur J Prev Cardiol 2022;29:2240-2249; Eur J Prev Cardiol 2021;28:e13-e15; BMC Med 2015;13:207]

Discussing the potential mechanisms underlying the effect of coffee on AF, the investigators noted that caffeine could have adenosine-mediated antiarrhythmic properties. “Adenosine facilitates AF induction… [and] caffeine concentrations associated with typical coffee consumption result in blockade of A₁ and A_2a adenosine receptors.”

Coffee could also lower the risk of AF through its anti-inflammatory properties and diuretic effects, they added.

“It is worth emphasizing that the caffeine in this study was naturally occurring and coffee consumption was within normal ranges. It would be inappropriate to extrapolate any perceived benefits to high-dose caffeine, and particularly to synthetic products such as energy drinks that might contain other substances,” the investigators said.

Overall, the present data provide reassurance to patients with AF, who enjoy coffee or other caffeinated products, and their clinicians, they continued. “Given the apparent protective effects, strategies to encourage or even initiate caffeinated coffee as a proactive strategy to prevent AF may be worthwhile investigating.”

DECAF included 200 patients (average age of 69 years, 71 percent male, 80 percent White, 52 percent were taking antiarrhythmic medication), current or previous (within past 5 years) coffee-drinking adults with persistent AF, or atrial flutter with a history of AF, who were scheduled to undergo electrical cardioversion at five hospitals across the US, Canada, and Australia.

The patients were randomly allocated to the coffee drinking arm or the abstinence arm. Those in the coffee drinking arm were encouraged to drink at least one cup of caffeinated coffee daily for 6 months, while those in the abstinence arm were encouraged to completely abstain from both caffeinated and decaffeinated coffee and other caffeine-containing products. Baseline characteristics were largely balanced between the two arms.

During the 6-month trial period, coffee intake did not significantly change in the coffee drinking arm, with baseline and follow-up intake of 7 cups per week. In the abstinence arm, coffee intake decreased from 7 cups per week at baseline to 0. Intake of other caffeinated products, such as tea, chocolate, energy drinks, soda, and decaffeinated coffee, was numerically higher in the coffee consumption group throughout. However, sugar consumption, which was added to coffee, was greater in the coffee drinking arm.