Daily consumption of caffeinated coffee did not result in significantly more daily premature atrial contractions than the avoidance of caffeine, according to findings of the Coffee and Real-time Atrial and Ventricular Ectopy (CRAVE) trial. The authors pointed out several significant differences: “Our results further suggest that both assignment to daily coffee consumption and greater-than-normal coffee consumption were associated with more recorded daily steps taken, fewer minutes of sleep per night, and potentially more daily premature ventricular contractions among persons who consumed more than one coffee drink per day.”
The prospective, randomized, case-crossover trial of 100 adults was designed to detect the effects of caffeinated coffee on cardiac ectopy and arrhythmias, daily step counts, sleep minutes, and serum glucose levels. Participants were fitted with a continuously recording electrocardiogram device, a wrist-worn accelerometer, and a continuous glucose monitor, and were tracked using geolocation data. Daily text messages over 14 days randomly instructing participants to consume caffeinated coffee or avoid caffeine had these effects on a primary outcome of the mean number of daily premature atrial contractions: “The mean (± SD) age of the participants was 39 ± 13 years; 51% were women, and 51% were non-Hispanic White. Adherence to the random assignments was assessed to be high. The consumption of caffeinated coffee was associated with 58 daily premature atrial contractions as compared with 53 daily events on days when caffeine was avoided (rate ratio, 1.09; 95% confidence interval [CI], 0.98 to 1.20; P = 0.10). The consumption of caffeinated coffee as compared with no caffeine consumption was associated with 154 and 102 daily premature ventricular contractions, respectively (rate ratio, 1.51; 95% CI, 1.18 to 1.94); 10,646 and 9665 daily steps (mean difference, 1058; 95% CI, 441 to 1675); 397 and 432 minutes of nightly sleep (mean difference, 36; 95% CI, 25 to 47); and serum glucose levels of 95 mg per deciliter and 96 mg per deciliter (mean difference, −0.41; 95% CI, −5.42 to 4.60).”