Effect of Coffee on Heart Rhythm Reexamined
Whether coffee causes arrhythmias has been hard to prove, because most studies of coffee have been observational. But thanks to the Coffee and Real-time Atrial and Ventricular Ectopy (CRAVE) trial, presented at the American Heart Association Scientific Sessions in November 2021, we have better data. For two weeks, healthy volunteers drank as much coffee as they wanted for a day and avoided caffeine the following day. Their heart rhythm was tracked with a continuous monitor, and their sleep and activity were tracked with a FitBit. At the end of the study, no relationship between coffee consumption and premature atrial contractions was seen, but coffee drinkers experienced a 54% increase in premature ventricular contractions on days they drank coffee. Notably, the risk of supraventricular tachycardia dropped by 12% with each cup of coffee consumed. None of these arrhythmias are generally cause for concern. Not surprisingly, participants took more than 1,000 extra steps and slept 36 fewer minutes on days they drank coffee.
