Premature atrial and ventricular contractions contribute to the development of atrial fibrillation (AF) and heart failure (HF), respectively. Decreasing exposure to modifiable risk factors could contribute to decreasing the burden of these diseases. In the CRAVE trial, researchers looked at the impact of caffeine on atrial contraction.
Caffeine consumption has long been purported to trigger cardiac ectopy. However, population-based studies have failed to demonstrate an association between caffeine consumption and the development of clinically significant arrhythmias. The CRAVE clinical trial (NCT03671759) sought to clarify this relationship using an n-of-1 strategy in a prospective, randomized, case-crossover trial.
Investigators recruited 100 adults to explore how the consumption or avoidance of caffeinated coffee impacted cardiac ectopy and arrhythmias. Pre-existing AF or HF, or the presence of an implantable cardioverter defibrillator or a pacemaker all constituted grounds for exclusion.
Participants wore an automatically recording electrocardiographic monitor, continuous glucose monitor, and a fitness tracker over a period of two weeks. During the study period, participants either consumed or avoided caffeine based on randomized text message instructions from investigators. Any change in premature atrial contraction (PAC) frequency constituted the primary outcome measure. Secondary outcome measures included mean daily glucose levels and mean sleep duration.
No significant changes between consuming or avoiding caffeine
ECG recordings demonstrated 58 daily PACs on caffeine consumption days as compared with 53 daily PACs on caffeine avoidance days (rate ratio, 1.09; 95% confidence interval [CI], 0.98 to 1.20; P=0.10).
Serum glucose levels differed by only 1 mg per deciliter on caffeine consumption days versus caffeine avoidance days. Researchers documented that 397 minutes of nightly sleep on caffeine consumption days as compared with 432 minutes on caffeine avoidance days.
Investigators concluded that the CRAVE trial showed that caffeine consumption did not result in more PACs than the avoidance of caffeine.
Author: Kelly Schoonderwoerd
Original Article: Marcus GM et al. N Engl J Med 2023;388:1092-1100.