Los Angeles: Coffee lovers, relax! Contrary to current belief, regular caffeine consumption does not lead to extra heartbeats, which causes heart- or stroke-related morbidity and mortality in rare cases, scientists, including one of Indian-origin, have found.
The study by researchers from University of California in San Francisco (UCSF) measured the chronic consumption of caffeinated products over a 12-month period, rather than acute consumption.
It is the largest study to date to have evaluated dietary patterns in relation to extra heartbeats. Excessive premature atrial contractions (PACs) have been
shown to result in atrial fibrillation, stroke and death, while excessive premature ventricular contractions (PVCs) have been shown to result in increased heart failure, coronary artery disease and death.
Both abnormalities have been tied to caffeine consumption through studies and trials, but these studies were performed several decades ago and did not use PACs and PVCs as a primary outcome. Researchers analysed 1,388 randomly selected participants from the National Heart, Lung, and Blood Institute (NHLBI)
Cardiovascular Health Study database of nearly 6,000 patients, excluding those with persistent extra heartbeats.
They were given a baseline food frequency assessment and 24-hour ambulatory electrocardiography monitoring. Frequencies of habitual coffee, tea and chocolate consumption were determined through a survey.
Of the total participants, 840 (61 per cent) consumed more than one caffeinated product daily. The researchers found no differences in the number of PACs or PVCs per hour across levels of coffee, tea and chocolate consumption.
More frequent consumption of these products was not associated with extra heartbeats. "Clinical recommendations advising against the regular consumption of caffeinated products to prevent disturbances of the heart's cardiac rhythm should be reconsidered, as we may unnecessarily be discouraging consumption of items like chocolate, coffee and tea that might actually have cardiovascular benefits," said Gregory Marcus from UCSF.
"This was the first community-based sample to look at the impact of caffeine on extra heartbeats, as previous studies looked at people with known arrhythmias," said lead author Shalini Dixit, a fourth-year medical student at UCSF.
The findings were published in the journal of the American Heart Association.
