If you work more than 55 hours a week, then you may be at risk of developing serious heart problems.

Reports claim people who work long hours are 40 percent more susceptible to an irregular heartbeat compared to those who work 35 to 40 hours a week.

Long shifts were already known to increase the risk of stroke. However, it was not previously known that long shifts are linked to heart rhythm problems referred to as atrial fibrillation.

Atrial fibrillation affects millions of people, is the most common heart rhythm disturbance, and can lead to stroke, heart failure and dementia.

A study of more than 85,500 people found those who worked long hours were far more likely to develop atrial fibrillation over the next decade. For every 1,000 people in the study, an extra 5.2 cases of atrial fibrillation occurred among those working long hours.

Study leader Professor Mika Kivimaki of University College London said the following on the matter: “Those who worked long hours had a 1.4 times higher risk of developing atrial fibrillation, even after we had adjusted for factors that could affect the risk, such as age, sex, socio-economic status, obesity, leisure time physical activity, smoking and risky alcohol use.”

“Nine out of 10 of the atrial fibrillation cases occurred in people who were free of pre-existing or concurrent cardiovascular disease. This suggests the increased risk is likely to reflect the effect of long working hours rather than the effect of any pre-existing or concurrent cardiovascular disease, but further research is needed to understand the mechanisms involved.”

She added: “A 40 per cent increased extra risk is an important hazard for people who already have a high overall risk of cardiovascular disease due to other risk factors such as older age, male sex, diabetes, high blood pressure, high cholesterol, overweight, smoking and physical inactivity, or living with an established cardiovascular disease.”

“For a healthy, young person, with few if any of these risk factors, the absolute increased risk of atrial fibrillation associated with long working hours is small.”