Smoking elevates risk of a heart rhythm disorder

The more one smokes, the greater is the risk of a heart rhythm disorder

Smoking increases the risk of heart rhythm disorder called atrial fibrillation (AF). This finding was published in the European Journal of Preventive Cardiology, a European Society of Cardiology (ESC) journal.

The study found a 14% increase in the risk of atrial fibrillation for every ten cigarettes smoked per day. There was a linear dose-response relationship, meaning that the risk increased with each additional cigarette smoked.

In comparison to people who had never smoked, current smokers had a 32% increased risk of atrial fibrillation, while ever smokers (current and former smokers combined) had a 21% increased risk, and former smokers had a 9% increased risk.

“If you smoke, stop smoking and if you don’t smoke, don’t start,” said study author Dr Dagfinn Aune, postdoctoral researcher at Imperial College London, UK, and associate professor at Bjørknes University College in Oslo, Norway.

He added: “We found that smokers are at increased risk of atrial fibrillation, but the risk is reduced considerably in those who quit.”

A lifetime smoker has a 50% probability of dying due to smoking, and on average will lose ten years of life. Slightly less than half of lifetime smokers will continue smoking until death. The rate of casual and social smoking is on the rise among young men, women and adolescents across India with many of them considering it to be a “stress buster”.

According to the Tobacco Atlas which estimates the prevalence of tobacco use across the world, more than 932600 of Indians are killed by tobacco-caused diseases every year. Still, more than 625000 children (10-14 years old) and 103614000 adults (15+ years old) continue to use tobacco each day. The Global Adult Tobacco Survey 2016-17 estimated that 19.0% of men, 2.0% of women and 10.7% (99.5 million) of all adults currently smoke tobacco in India.

Smoking five, ten, 15, 20, 25 and 29 cigarettes per day was associated with a 9%, 17%, 25%, 32%, 39%, and 45% increased risk of atrial fibrillation

Atrial fibrillation is the most common heart rhythm disorder (arrhythmia). It causes 20-30% of all strokes and increases the risk of dying prematurely. One in four middle-aged adults in Europe and the US will develop atrial fibrillation. According to RELY-AF study, patients of AF from Africa, India and the Middle East were on average 10-12 years younger than those from other regions of the world.

This dose-response relationship between the number of cigarettes smoked and the risk of atrial fibrillation was the result of a meta-analysis of 29 prospective studies from Europe, North America, Australia and Japan with a total of 39,282 incident cases of atrial fibrillation among 677,785 participants.

Compared to zero cigarettes per day, smoking five, ten, 15, 20, 25 and 29 cigarettes per day was associated with a 9%, 17%, 25%, 32%, 39%, and 45% increased risk of atrial fibrillation, respectively.

Risk of developing atrial fibrillation increased by 16% for every ten pack-years of smoking. Pack-years were calculated by multiplying the number of packs of cigarettes smoked per day by the number of years the person has smoked. European guidelines on the prevention of cardiovascular disease recommend avoiding tobacco in any form.

Dr Aune said: “Our results provide further evidence of the health benefits of quitting smoking and, even better, to never start smoking in the first place. This is important from a public health perspective to prevent atrial fibrillation and many other chronic diseases.”