Going home to a hug from a supportive spouse - male or female - brings down blood pressure boosted by a nightmare day at work, a study finds.

The University of Toronto study, presented to an American Heart Association meeting, monitored 216 men and women for a year. Those with stressful jobs but close relationships saw blood pressure fall.

In separate research, British heart experts are investigating a stress enzyme linked to heart damage.

The British Heart Foundation research was announced to mark World Heart Day.

Scientists will investigate the role of 11HSD1, a fat cell enzyme which controls levels of the stress hormone cortisol.

Animal studies showed having higher levels of this enzyme were linked to an increased risk of obesity.

'Marital cohesion'

In the Canadian research, researchers monitored doctors, nurses, administrators, maintenance workers and visitors at the University of Toronto Health Sciences Center.

All were aged 40 to 65, employed, and had been living with a partner for the previous six months.

At the beginning of the study, everyone's blood pressure was monitored for 24 hours over the course of a working day.

No one in the study was being treated for high blood pressure.

Participants were also assessed to see how demanding their jobs were. The key components of job strain were found to be a highly demanding job where the person had little control over what they did.

Another test was used to evaluate "marital cohesion".

The same checks were carried out a year later.

Those who had a demanding job combined with support at home saw a small fall in blood pressure levels over the year.

The researchers say the findings are significant because blood pressure tends to rise as people age.

Those who had stressful jobs and a lack of support at home did see the expected rise.

Some challenge 'good'

Professor Sheldon Tobe, who led the study, said: "Job strain had a significant impact, both clinically and statistically, on blood pressure."

He added: "The medical model of healthcare does not include job strain, but stress at work and at home can modify the health of patients."

Professor Tobe said: "The amount of support given at home in the relationship is a major definition of marital cohesion. "

He added people who had high job strain and/or low marital cohesion - or if a happy relationship had deteriorated, they should see their family doctor for a blood pressure check.

Dr Charmaine Griffiths, spokesperson for the British Heart Foundation, said: "A degree of challenge is necessary for us to feel motivated and enthusiastic, but too much stress can cause ill health.

"Getting the balance right and having emotional support, whether from loved ones or friends, helps us cope with stress in a positive way."