By Adam Brimelow
Health correspondent, BBC News
A heart attack deprives the heart of oxygen, causing permanent damage
Stress at work raises the risk of heart disease for women under 50, a study of more than 12,000 nurses suggests.
Danish research in Occupational and Environmental Medicine concludes work pressure has a greater effect on young women than those in their 50s and 60s.
It suggests other risk factors may play a bigger role in the development of heart disease for older women.
The British Heart Foundation says people facing stress at work should try to tackle it in a positive way.
There is a lot of evidence indicating that stress at work raises the risk of heart disease in men, but there has been much less research examining the impact on women.
In this study, the researchers asked more than 12,000 female nurses aged between 45 and 64 about pressure at work and tracked their health for 15 years up to 2008.
By then 580 nurses had been admitted to hospital with ischaemic heart disease, including 369 cases of angina and 138 heart attacks.
After accounting for risk factors such as smoking and diabetes, the researchers found that those who described pressure at work as "much too high" were 35% more likely to have developed heart disease than those who were comfortable with the pressure.
But when they broke the results down by age, they found it was only the women aged 50 and under who were affected significantly.
The researchers from Glostrup University Hospital, in Denmark, say this could be down to a changing risk-profile in different age groups.
"It seems as if the effect of work pressure has a greater impact on younger women," they said.
"This is in agreement with findings from previous studies looking at age-specific effects in both men and women.
"The lower risk among the older nurses may be due to other risk factors that become relatively more important with increasing age."
June Davison, a cardiac nurse with the British Heart Foundation, said people who were stressed at work should talk to colleagues or managers about how to manage the pressures.
"If you feel under pressure you should try and tackle it in a positive way and get active during work hours," she said.
"Using the stairs and walking some of the way to work could help act as a stress buster and boost heart health too."
Josie Irwin, head of employment relations at the Royal College of Nursing, said the paper raised important concerns.
"Our latest employment survey found that 55% of nurses feel they are under too much pressure at work, making this research worrying reading," she said.
"We know that safe staffing levels are key to providing the best quality care for patients - this research also suggests under-staffing and excess pressure can have a damaging effect on nurses' health."