Nutrition

Regular Caffeine Consumption Not Linked to Arrhythmias

No relationship exists between chronic consumption of caffeine and arrhythmias, particularly cardiac ectopy, determined by 24-hour Holter monitoring, according to a new study.

Importantly, these results came from a community-based population and not patients complaining of palpitations or those selected from a medical practice, said study author Gregory M. Marcus, MD, MAS, of the division of cardiology at the University of California, San Francisco.

Researchers examined Cardiovascular Health Study participants with a baseline food frequency assessment and 24-hour ambulatory electrocardiography. They assessed frequencies of habitual coffee, tea, and chocolate consumption with a picture-sort food frequency survey. The main outcomes were premature atrial contractions (PACs)/hour and premature ventricular contractions (PVCs)/hour.

Among 1388 subjects (46% male, mean age 72 years), 840 (61%) consumed ≥1 caffeinated product per day. The median numbers of PACs and PVCs/h and interquartile ranges were 3 (1-12) and 1 (0-7), respectively.

They found no differences in the number of PACs or PVCs/h across levels of coffee, tea, and chocolate consumption. Even after adjusting for potential confounders, the investigators didn’t see more frequent consumption of these products associated with ectopy. When examining combined dietary intake of coffee, tea, and chocolate as a continuous measure, they observed no relationships after multivariable adjustment: 0.48% fewer PACs/h (95% CI −4.60 to 3.64) and 2.87% fewer PVCs/h (95% CI −8.18 to 2.43) per 1-serving/week increase in consumption.

“Given common recommendations to avoid caffeine in order to reduce ectopy, we were surprised that no positive relationship between caffeine consumption and frequency of ectopy was evident,” said Marcus, who noted two study limitations. “First, we did not examine acute consumption of caffeine. We also do not know how much caffeine was consumed on the day of the actual Holter study.”

He went on to say data supporting the notion that caffeine leads to arrhythmias is “sparse” in general, with more studies failing to identify a relationship than seeing positive associations. “It may be that caffeine as a trigger is idiosyncratic to some, but our findings suggest it would not be appropriate to generalize this to all individuals broadly,” Marcus said.

He has several ongoing projects investigating both modifiable predictors of cardiac ectopy and the effects of cardiac ectopy. Marcus also is a principal investigator on the Health eHeart Study (https://www.health-eheartstudy.org), an ongoing internet-based cardiovascular cohort study. “The hope is to use technology to enhance our understanding of various forms of heart disease,” he explained.

-Mike Bederka

Reference:

Dixit S, Stein PK, Dewland TA, et al. Consumption of caffeinated products and cardiac ectopy. J Am Heart Assoc. Published online January 26, 2016. doi:10.1161/JAHA.115.002503.