A call for personalized guidance
“As the investigators note, there are definitely biologically plausible reasons how coffee and caffeine may not cause arrhythmias, and may be possibly protective in some, despite being a stimulant,” Dr. Goldberger said. “However, if your patient is reporting palpitations or symptoms of an arrhythmia, and feels they be related to coffee or caffeine, we should not use this study to tell them that coffee may not be the culprit. We need to listen to our patients, and the decision to reduce coffee consumption to reduce these symptoms needs to be personalized.”
The effect size was small, and only about 4% of the participants developed an arrhythmia, Dr. Goldberger and Rodney A. Hayward, MD, wrote in an invited commentary on the study in JAMA Internal Medicine. Dr. Hayward is a professor of public health and internal medicine at the University of Michigan, Ann Arbor, and a senior investigator at the Ann Arbor Veterans Affairs Center for Clinical Management Research.
“Unfortunately, coffee consumption was self-reported at a single time point. Not only can this lead to recall bias, but subsequent and substantial changes in coffee consumption are also possible, including reductions due to new signs or symptoms,” they said.
No evidence that coffee ups risk for developing arrhythmias
Another recent study suggests that people may alter their coffee consumption depending on their baseline cardiovascular health, according to the commentary.
Overall, the results “strengthen the evidence that caffeine is not proarrhythmic, but they should not be taken as proving that coffee is an antiarrhythmic—this distinction is of paramount importance,” Dr. Goldberger and Dr. Hayward wrote. “Health care professionals can reassure patients that there is no evidence that drinking coffee increases the risk for developing arrhythmias. This is particularly important for the many patients with benign palpitations who are devastated when they think, or are told, that they have to stop drinking coffee. Given current evidence, this is entirely a patient-preference decision, not a medical one.”
Dr. Marcus, a cardiac electrophysiologist, sees patients with arrhythmias all the time. They tend to “come in fairly convinced that caffeine is to be avoided when they have arrhythmias,” he said. “Often, they been told by their primary care physician or their general cardiologist to avoid caffeine because they have an arrhythmia.
“What I suggest to my patients is that they feel free to go ahead and experiment and try coffee,” Dr. Marcus said.
Still, Dr. Marcus suspects that there are some individuals in whom caffeine is a trigger for the arrhythmia. But evidence indicates these cases likely are rare, and avoiding caffeine need not apply to the general population, particularly “given the potential health benefits of benefits of coffee and also, frankly, just the enhanced quality of life that people can enjoy drinking a good cup of coffee.”
The research was conducted using the UK Biobank resource, which was established by the Wellcome Trust, the Medical Research Council, the U.K. Department of Health, and the Scottish government. The UK Biobank has received funding from other agencies and foundations as well. Dr. Marcus disclosed grants from Baylis, Medtronic, and Eight Sleep outside the submitted work. In addition, he reported consulting for Johnson & Johnson and InCarda, and holding equity in InCarda. A coauthor received salary support from the National Institutes of Health during the study. Dr. Goldberger and Dr. Hayward disclosed no conflicts of interest.