Caffeine Doesn't Bring on Atrial Fibrillation, Arrhythmias, Study Finds

Despite decades of clinical advice that caffeine is bad for the heart, there has been little actual study of its effects. A California team said moderate consumption does not affect the performance of the heart or trigger arrhthymias.

Premature cardiac contractions—known to initiate paroxysms of atrial fibrillation—are not brought on by chronic consumption of caffeine, a California team reports.

Writing in the Journal of the American Heart Association, Gregory Marcus, MD, MAS of the University of California San Francisco and colleagues analyzed the caffeinated beverage consumption of 1,416 individuals.

Their caffeinated beverage drinking habits were assessed and they were given 24-hour Holter monitoring.

The electro cardiogram data was reviewed to look for PACs and ventricular ectopic beats (PVCs) per hour and correlated with cafeeine consumption times.

They were also categorized by demographics, body mass index, caloric intake, diabetes status, smoking status and alcohol consumption habits.

Twenty-eight individuals had to be excluded from the study because they had persistent atrial fibrillation throughout the study.

Greater than 60% of participants reported driving at least one caffeinated beverage daily. One study shortcoming is that they asked only about coffee, tea, and chocolate drinks—not sodas.

“Though caffeine consumption has long been related to cardiac ectopy and arrhythmias by anecdote and biological plausibility, few studies have demonstrated any relationship,” the team noted.

Despite the lack of research, clinicians often recommend that patients avoid caffeine.

Though they were not able to determine whether there was a maximum threshold for safe caffeine consumption, “our findings suggest that clinical recommendations advising against the regular consumptions of caffeinated products to prevent cardiac ectopy and arrhythmia should be reconsidered,” the team concluded.

“Our results support a long history of data from both experimental and observational trials indicating that moderate consumption of caffeine is not associated with cardiac ectopy and extend that evidence from predominately arrhythmia patients to a community‐based cohort,” they wrote.