Scientists have known for some time that marital stress can damage a person's heart, but now it turns out that the scenario is quite different for husbands and for wives.
For wives, the most damaging stress comes from hostility, either hers or his.
For husbands, it's the need to feel in control, and heart damage occurs when the wife asserts control, or when the husband feels the need to dominate his mate.
A new study from the University of Utah underscores the effects of marital stress in a measurable way. Researchers who studied 150 couples who had been married an average of 27 years found a direct correlation between different kinds of stress and hardening of the coronary arteries, or atherosclerosis, which can lead to heart attacks and possibly death.
The difference between the genders is quite pronounced, says psychologist Tim Smith, who led the research team. Women suffered heart damage in the presence of hostility, but men didn't. Conversely, men suffered coronary damage if their control was questioned, but women didn't.
Although the purpose of the study was to evaluate "interpersonal risk factors for coronary disease," Smith says, it probably says as much about gender identification and role-playing as it does about marriage.
Women need to feel loved and need to be treated with tenderness.
Men need to dominate, and play the role of the boss.
"How warm and friendly the relationship is, versus cold and hostile, seems to capture the attention more of women then men, and the opposite is true for dominance and control," says Smith, who presented the findings at a recent meeting of the American Psychosomatic Society, whose concern is the influence of psychological factors on physical health.
The findings are consistent with a large body of research showing that the quality of a marriage, or even just the fact of being married, can have a significant impact on health. But most of those earlier studies consisted of self-reporting by marriage partners, and the Utah team wanted to take it a step further.
In an effort to measure the impact of marital stress, the researchers recruited 150 couples, most of whom were in their 60s, and none of whom had any history of cardiovascular disease. They chose older couples because it takes years for calcification to build up in the arteries, and that's what they wanted to measure.
The couples, who were paid $300 for their services, were told they would be asked to discuss the source of stress in their marriage.
"We gave them sort of a top 10 list of things couples fight about," says Smith. "That included things like money (which always ranks near the top) in-laws, household responsibilities, vacations, kids and the usual stuff."
Each couple picked which subject they wanted to discuss. Then while seated in front of a video camera, they got into it.
Sometimes, the researchers say, the bickering got so intense that the couples were later referred to counselors.
A subsequent CT scan turned up the evidence the researchers had been looking for. Husbands and wives both showed some hardening of the arteries, but in response to different types of stress.
"What we find stressful depends on who we are," Smith says, "and one of the aspects of who we are is gender."
But why should there be such a difference? Smith points out that numerous research projects in recent years have demonstrated something most of us already knew. Men are different from women.