Researchers gave nearly 700 men and women with heart disease a mentally stressful public speaking assignment. Then they measured blood flow to the heart.
Women aged 50 or younger were nearly four times more likely than men of the same age or older women to have reduced blood flow to the heart, said study leader Dr. Viola Vaccarino. She is chair of epidemiology at Emory University Rollins School of Public Health in Atlanta.
Reduced blood flow — known medically as myocardial ischemia — can lead to a heart attack, she noted.
“Younger women appear to be more vulnerable [than men and older women] to the effects of stress on their heart,” Vaccarino said.
Experts have long known that younger women have worse outcomes than men of the same age after a heart attack, but they could not fully explain it. This finding may help close that gap, she said.
The new study could provide some missing information, agreed Dr. Suzanne Steinbaum, director of women’s heart health at Lenox Hill Hospital in New York City.
“I don’t think we have the full picture of why young women do worse, but I believe this can definitely be a piece to the puzzle,” said Steinbaum, who is also a spokeswoman for the American Heart Association program Go Red for Women.
In the study, the researchers evaluated 686 patients, aged 34 to 79, who had stable heart disease. Some had had heart attacks, others had other conditions such as angina (chest pains).
“We asked them to deliver a speech on a topic we gave them,” she said. The audience was instructed not to respond positively, which added to their stress.
Imaging tests before and after the speeches revealed that “younger women had much reduced blood flow to the heart compared to men of the same age,” Vaccarino said. She did not find those differences in men and women at older ages, she noted.
Reduced blood flow occurred in one-third of women aged 50 or younger, but only in 8 percent of men in that age group.
The data suggest that stress may be an especially important factor for women who have heart disease, said Vaccarino.
Stress could help explain the worse outlook for younger women, Steinbaum said, although other factors play in, too, such as the severity of heart disease.
As they juggle work, family and financial responsibilities, many women in their 30s, 40s and early 50s routinely feel stressed, the researchers said.
The study suggests that younger and middle-aged women with heart disease — and those at risk of it — may need more assessment of life stressors and additional support to cope with them, both doctors agreed.
“Women need to understand they need support; they need to understand how to put things in perspective,” Steinbaum said.
Doctors should ask about stress levels and depression, and refer women to counseling if necessary, Vaccarino said.
Women hoping to avoid heart disease should also try to handle their stress, and develop an exercise habit if they haven’t already, Vaccarino added. “We know that the same pattern [of stress and blood flow] may apply to those who have not yet had a heart attack,” she said.
“Exercise has been shown to reduce the risk both of depression and psychological stress as well as heart disease,” she said. “By doing that, women can take care of their heart as well as their mind.”
The study was published Aug. 24 in the Journal of the American Heart Association.