The researchers found that people who worked nights for long periods of their lives had an increased risk of atrial fibrillation and heart disease, but not stroke or heart failure.

Atrial fibrillation is a heart rhythm disorder that results in a fast or slow heartbeat or an irregular heartbeat.

Recently published in the European Heart Journal, the scientists examined what genetic predisposition to atrial fibrillation might play a role in increasing the risk. They assessed overall genetic risk based on 166 genetic variants known to be associated with the condition.

But they found that genetic risk levels did not affect the association between night work and atrial fibrillation risk, regardless of whether participants had low, medium or high genetic risk.

Study leader Professor Yingle Lu said: 'Although a study like this cannot show a causal relationship between night work and atrial fibrillation and heart disease, our results suggest that over time it increases the risk of these conditions.

He continued, "Our results guide us to follow some measures to prevent atrial fibrillation, as reducing the frequency and duration of night work may be beneficial for cardiovascular health."

The researchers found that people who worked nights on a regular or regular basis had a 12 percent increased risk of developing atrial fibrillation, compared to people who worked only during the day.

The risk increased to 18 percent after 10 years or more for those who worked nights for a lifetime.

The risk of developing atrial fibrillation also increased to 22 percent among people who worked an average of three to eight night shifts per month for ten years or more, compared to day workers.

Among participants who currently work nights, or for ten years or more, or work for life from three to eight night shifts per month, the risk of coronary heart disease increased by 22 percent, 37 percent, and 35 percent, respectively, compared to day workers.

Professor Chi said: 'There were two more interesting findings. We found that women were more likely to develop atrial fibrillation than men when working night shifts for more than ten years, where the risk increased significantly, when it reached 64 percent compared to workers in the morning shift. ".

He added: "People who did an optimal amount of physical activity of 150 minutes per week or more of moderate intensity had a lower risk of developing atrial fibrillation than those who engaged in suboptimal physical activity when exposed to lifelong night shifts.

Scientists advise - in particular - women and people who engage in physical activity to reduce work at night.