Coffee Consumption and Arrhythmia Incidence

It is commonly believed that consuming caffeine in coffee can have adverse effects on individuals with arrhythmia. However, findings of a new study1 appear to debunk that myth.

According to results of the study, compared with no coffee consumption, regular coffee consumption is associated with a significantly lower risk of arrhythmia. In fact, each additional daily cup of coffee was associated with a 3% lower incidence of arrhythmia.

Consultant360 asked lead investigator Eun-Jeong Kim, MD, about these findings, which were released as part of Heart Rhythm Society 2020 Science. Dr Kim, who is a cardiac electrophysiology fellow at the University of California, San Francisco, explains how the results debunk current myths about coffee consumption and how the research can guide the advice you give your patients.

CONSULTANT360: What was the impetus for your study? What knowledge gaps were you hoping to bridge?

Eun-Jeong Kim: Coffee is one of the most consumed beverages in the world, yet it is known to be a stimulant and is commonly perceived as harmful for individuals with cardiovascular (CV) conditions, particularly arrhythmia. Many physicians still advise patients to avoid coffee intake if the patients have preexisting CV conditions. However, these beliefs are not based on solid scientific evidence. It has been shown that caffeine has antioxidant and anti-inflammatory properties. Multiple studies have shown the potential benefit of coffee with multiple chronic medical conditions, such as CV disease, diabetes, and certain types of cancers, as well as with all-cause mortality. We aimed to investigate the relationship between coffee intake and incident arrhythmia. 

CON: In what ways do your findings address/debunk the myths surrounding caffeine and its effect on arrhythmia?

EJK: Our study found that moderate habitual coffee drinking actually decreased the risk of incident arrhythmia. This held true specifically for atrial fibrillation/flutter.

CON: How do you hope these findings will impact clinical practice in terms of guideline updates, best practices statements, or management decisions?

EJK: There are no specific guidelines on coffee drinking among the general population or those with preexisting CV conditions. Nevertheless, patients are commonly misinformed on the effect that coffee drinking has on their health. Based on our study findings, we hope to inform our colleagues and patients that coffee drinking does not increase the risk of arrhythmia and, rather, may have health benefits. 

CON: How should these findings guide any future conversations clinicians have with their patients about caffeine consumption in regard to arrhythmia risk?

EJK: Our study showed that each additional daily cup of coffee—up to 6 cups daily—decreased the risk of incident arrhythmia. Considering the limitation of the prospective study and potential selection bias, the main message regarding patients’ risk of overall arrhythmia would be that it is certainly not deleterious to continue with a moderate amount of habitual coffee intake. For each analysis, we excluded the relevant prevalent condition; since we excluded those who have certain arrhythmia conditions at baseline, we do not know the effect of caffeine among this population specifically. 

CON: You say that this study’s data will lead to and support larger, randomized interventional studies. What can clinicians expect from this future research?

EJK: Our study is a prospective cohort study. Although it is based on a large population, it is not a randomized controlled trial and, thus, it is subject to biases. One limitation is that people with possible arrhythmic symptoms might self-limit their caffeine intake, affecting the outcome. A large randomized study will be able to confirm or dispute this study finding. 


  1. Frequent coffee consumption is associated with lower incidence of arrhythmias. News release. Heart Rhythm Society. May 5, 2020. Accessed June 1, 2020.