NEW YORK (Reuters Health) - People in stressful jobs show a rise in their average blood pressure over one year if they have a poor relationship with their spouse, a new study shows. Conversely, people experiencing job strain who have good marital relationships saw their blood pressure fall by the same amount.

"People with both high job strain and low marital cohesion may benefit from having their blood pressure regularly assessed," Dr. Sheldon W. Tobe and colleagues from the University of Toronto write in the American Journal of Hypertension.

Tobe and his team conducted the study to examine whether job factors and marriage quality -- both of which have been shown, separately, to influence health -- might interact to affect blood pressure.

They followed 229 men and women for one year, all of whom were living with a spouse or partner and were free from hypertension at the study's outset. Tobe and his team looked specifically at couples' "marital cohesion," or how much couples support one another. Study participants wore ambulatory monitors that checked their blood pressure throughout the course of a typical working day, at the study's outset and again one year later.

Individuals reporting high levels of job strain who had low marital cohesion had a 3-point increase in their systolic blood pressure, the top number in a blood pressure reading. On the other hand, those with very cohesive marriages who were experiencing job strain had a 3-point drop in their systolic blood pressure.

When the researchers looked at men and women separately, the relationship among stress, blood pressure and marital cohesion remained strong for women, but it disappeared for men, suggesting the effect may be gender-specific. Being stressed on the job while having little control over work demands can boost inflammation and levels of stress hormones, the authors note. "In an affected individual, the soothing effect of high marital cohesion may lower blood pressure by reversing this effect," they suggest.