Atrial fibrillation (AF) is the most prevalent cardiac arrhythmia. It is affecting more than 10.5 million Americans and up to one in three globally during their lifetime. Identifying modifiable risk factors is crucial to reducing AF burden. Coffee is a widely consumed beverage in the U.S. and is rich in caffeine. Coffee has traditionally been considered a potential trigger for AF, and patients frequently report it as a contributing factor. Hence, doctors recommend that their patients decrease their intake of coffee. However, recent evidence, like multiple observational studies and the coffee and real-time atrial and ventricular ectopy (CRAVE) randomized clinical trial, shows no increase in premature atrial contractions/AF risk. This randomized trial investigated the effect of caffeinated coffee consumption versus abstinence in AF patients.
Does Eliminating Coffee Avoid Fibrillation? (DECAF) clinical trial (NCT05121519) was a multi-center, prospective, open-label, investigator-initiated, international, randomized study conducted across five tertiary hospitals in Canada, the U.S, and Australia. Adults aged ≥21 years with sustained AF or atrial flutter undergoing cardioversion and consumption of coffee of one cup/day or more for 5 years continuously were included in this study. Exclusion criteria included recent cardiothoracic surgery or AF ablation in the past 3 months, pregnancy or planning to conceive within 6 months, those who had adverse effects to coffee, and those who were not willing to continue or abstain from coffee consumption protocols.
A total of 200 patients were randomized by 1:1 to either consume caffeinated coffee daily (n = 100, mean age = 68.2±12.3 years, male = 76%, female = 24%, body mass index [BMI] = 30.3±7.9 kg/m²) or abstain completely (n = 100, mean age = 70.4±10.1 years, male = 65%, female = 35%, BMI = 30.4±7.5 kg/m²). These patients were followed at 1, 3, and 6 months through in-person visits, video, and phone calls. The primary outcome was recurrence of AF or atrial flutter, which was measured by electrocardiogram (ECG). The secondary outcomes were recurrence of atrial flutter, AF recurrence, and adverse reactions such as stroke, hospitalization, myocardial infarction, death, worsening heart failure, and emergency visits. Statistical analyses were performed by SAS software, version 9.4.
Baseline coffee intake was similar between groups (7 cups [interquartile range IQR: 7-18] per week). The intake of coffee remained stable in coffee groups (7 [IQR: 6-11] cups/week), whereas it dropped to near zero in abstinence group (0 [IQR: 0-2] cups/week), showing significant differences between groups was 7 cups/week (95% confidence interval [CI]: 7-7) throughout the clinical trial.
During follow-up, patients averaged six clinical visits and two ECGs, with 53% using continuous monitoring devices. After 6 months, AF recurrence occurred in 56% patients (n = 111) overall, including 47% in the coffee group and 64% in the abstinence group. Consumption of coffee reduced the recurrence of risk by 39% with a hazard ratio (HR) of 0.61 (95% CI: 0.42-0.89) and p = 0.01.
Detection methods for AF were similar across groups, though ECG-based detection was higher in the abstinence group, while wearable detection was higher in the coffee group. Intake of coffee decreased recurrence risk of AF (HR: 0.62, 95% CI: 0.43-0.91, p = 0.01). The difference in atrial flutter recurrence between groups was not statistically significant (HR = 0.37; 95% CI, 0.10–1.41; p = 0.14). There was no statistically significant difference observed in adverse reactions between the two groups.
Study limitations included its pragmatic design, lack of blinding, modest sample size, baseline imbalances in the abstinence group, self-reported coffee consumption, and variations in AF detection between groups.
The DECAF trial concluded that AF patients who consumed about one cup of caffeinated coffee daily had a lower recurrence of AF compared with abstinence.
Reference: Wong CX, Cheung CC, Montenegro G, et al. Caffeinated Coffee Consumption or Abstinence to Reduce Atrial Fibrillation: The DECAF Randomized Clinical Trial. JAMA. 2025. doi:10.1001/jama.2025.21056
