MONDAY, Feb. 27, 2006 (HealthDay News) -- British researchers have pinpointed the physical reasons why emotional stress can trigger a heart attack in some people.
Taking detailed measurements of 34 men who suffered heart attacks, a research team at University College in London found specific differences those who experienced anger, depression or stress in the hours before the attack, and those who did not.
In the 14 men whose heart attacks had an emotional trigger, blood pressure and heart activity took longer to return to normal. Blood tests showed they had significantly greater increases in platelets and other blood cells related to clot formation.
The study appears in this week's issue of the Proceedings of the National Academy of Sciences.
"Until now, there have been two sorts of studies, one of whether triggers do exist, the other looking at the biology of patients," said study author Andrew Steptoe, director of the university's Psychobiology Group. "This is the first study to combine the two things."
It seems clear that some people are more vulnerable to heart attacks "by virtue of the way in which they act biologically when confronted with a socially demanding situation," Steptoe said.
Now that the biological information is available, the next step is how to put it to work.
"In principle, we could be testing people, but it is premature to do that at the moment," Steptoe said. "There were no differences in temperament and background between the two groups. And even people who have emotional triggers experience emotions a lot more than they have heart attacks."
Also, the two groups of patients didn't differ in the way they felt about the experience, he said. "So we couldn't use subjective experience as a guide," Steptoe said. "Something is going on in more primitive parts of the brain."
His group is now trying to figure out what is going on, doing "various lines of research to identify these kinds of differences in the early stages," Steptoe said.
The report was hailed as "a very important observation" by Dr. James Young, director of the Bakken Heart-Brain Institute at the Cleveland Clinic. Young noted that Steptoe "has published other studies highlighting the heart-brain connection that we feel is so important."
"In the past, most studies have shown an endpoint link, with 'hot reactors' and the 'A-type personality,'" Young said. "What this study shows is that there actually is a physiological explanation for it."
Studies at the Bakken Institute include "projects that are looking at biofeedback methods of decreasing some stressors and using behavioral modification techniques," Young said.
An unsolved problem is how to identify individuals whose reaction to stress puts them at risk for heart attacks, he acknowledged. If those persons can be identified, "we have proposed that interventions at a certain time will be helpful," Young said.
To learn more about the relationship between stress and cardiac health, visit the American Heart Association.