Coffee doesn't risk your heart

Washington D.C.: A new study has found no association between coffee consumption and an increased risk of atrial fibrillation.

The research includes a meta-analysis of four other studies, making it the largest study its kind, involving nearly 250,000 individuals over the course of 12 years.

Moderate coffee consumption has been associated with a reduced risk of coronary heart disease and stroke. Its association with atrial fibrillation (AF), a heart condition that causes an irregular and often abnormally fast heart rate, has been unclear.

AF is the most frequent form of irregular heartbeat, causing a substantially increased risk of stroke, heart failure and all-cause mortality. It has previously been speculated that high coffee consumption may increase the risk of developing atrial fibrillation.

Lead author Susanna Larsson, from Karolinska Institutet, Sweden, said that they found no evidence that high consumption of coffee increases the risk of atrial fibrillation. This is important because it shows that people who like coffee can safely continue to consume it, at least in moderation, without the risk of developing this condition.

In sex-specific analyses, coffee consumption was associated with a non-significant increased risk of AF in men, but a non-significant decreased risk of AF in women. Whether men may be more sensitive to a high coffee or caffeine intake warrants further study, say the authors.

While the authors adjusted for major AF risk factors, they warn of possible bias and confounding factors that may have influenced their results, and highlight the limits of self-reported data. All studies were conducted in either Sweden or the US, thus reducing the generalizability of the results.

The study is published in the open access journal BMC Medicine.