Regularly staying late at the office significantly¹ increases the risk of having a stroke² or heart attack, researchers have found.

研究人员发现，经常在办公室里加班会使患中风或心脏病的风险显著增加。

Working just an hour extra each day pushes up stroke risk by 10 per cent, according to a huge review of working patterns.

And people who work an extra three hours a day - or 55 hours a week - are 33 per cent more likely to have a stroke, the scientists found.

The research, published in the Lancet medical journal³, is based on health records of more than 500,000 people across Europe, the US and Australia.

Scientists led by University College London warned that people who work longer hours tend to do less exercise, sit at a computer for hours at a time, and drink more than people with a better work-life balance.

Repeated stress may also be to be blame for greater health problems, the scientists think.

They looked at the combined result of 17 previous studies, in which 529,000 people were tracked over an average of seven years.

They found that people working 41 to 48 hours a week were 10 per cent more likely to suffer a stroke than those who worked a typical 35 to 40-hour week.

People who worked 49 to 54 hours a week had a 27 per cent increased chance of suffering a stroke.

And those who worked 55 or more hours were 33 per cent more likely to fall victim.