By Telegraph
It is thought that the stress of long hours can trigger biological changes in the body which lead to deadly disease
Those who spend longer at work were also more likely to develop heart
disease. Worryingly it is heart surgeons who work some of the longest
hours in Britain, with the average consultant spending 61.5 hours at
their post each week, the longest of any medical professional. Sudden death following long working hours is often caused by stroke, due to long and repeated periods of stress Dr Mike Knapton,
British Heart Foundation.
It is thought that the stress
of long hours can trigger biological changes in the body which, over
time, can lead to deadly disease.
“Health professionals should
be aware that working long hours is associated with a significantly
increased risk of stroke, and perhaps also coronary heart disease,” said
Mika Kivimäki, Professor of
Epidemiology at University College London.
Researchers looked at 25 studies involving more than 600,000 people
across Europe, the US and Australia who had been followed for an average
of 8.5 years.
The higher risk remained even when taking into account factors such
as smoking, alcohol consumption, and lack of physical activity which are
often associated with stressful jobs and longer hours.
Crucially the study showed that the longer people worked the higher
their chance of having a stroke became. Compared with people who worked
standard hours, those working between 41 and 48 hours had a 10 per cent
higher risk of stroke, and those working 49 to 54 hours had a 27 per
cent increased risk. Working 55 hours or more per week was linked to a
33 per cent greater risk of stroke.
Although the researchers
could only say that long hours were ‘linked’ to strokes, health experts
said it was ‘plausible’ that the stress of working too hard was to blame
and urged doctors to take extra care to check for signs of heart
problems in those with the most demanding jobs.
Dr Mike Knapton, Associate Medical Director, British Heart
Foundation, said: “This research shows an association between long
working hours and an increased risk of having a stroke and heart
disease.
“It is plausible that there could be a causal
relationship behind the link as sudden death following long working
hours is often caused by stroke, due to long and repeated periods of
stress, although that was not demonstrated in this study.
"This
study highlights to doctors that they need to pay particular attention
to cardiovascular risk factors when they advise people who work long
hours."
The average Briton works 36.7 hours per week, six hours
more than people in the Netherlands. The Greeks put in the longest
working week in Europe, averaging around 42 hours.
Previous
studies have shown that working long hours can lengthen the time it
takes for a woman to get pregnant. The University of California also
found that workers who clocked more than 51 hours a week were 29 per
cent more likely to have high blood pressure than those who worked 39
hours or fewer.
Dr Tim Chico, Reader in Cardiovascular Medicine / consultant
cardiologist, University of Sheffield, added: “For many people, reducing
their working hours would be difficult or impossible, and this study
does not show that it would reduce the risk of stroke.
“Most of
us could reduce the amount of time we spend sitting down, increase our
physical activity and improve our diet while working and this might be
more important the more time we spend at work.
“We should all
consider how the working environment could be altered to promote healthy
behaviour that will reduce strokes, irrespective of how long we work.”
Writing in a linked Comment, Dr Urban Janlert from Umeå University in
Sweden said the study showed it was more important than ever for
companies to stick to the EU Working Time Directive which limits the
working week to 48 hours.
The research was published in medical journal The Lancet.