Men and women are different from their body parts to their mental and emotional development, but up until now researchers didn’t know how different their hearts could be. In a study published in the Journal of the American College of Cardiology, heart disease and mental stress were compared between each gender. The findings will allow treatments to be more gender-based.

"The relationship between mental stress and cardiovascular disease is well known," said the study’s lead author Zainab Samad, assistant professor of medicine at Duke University Medical Center, in a press release. "This study revealed that mental stress affects the cardiovascular health of men and women differently. We need to recognize this difference when evaluating and treating patients for cardiovascular disease."

Researchers from the Duke Heart Center examined 254 men and 56 women diagnosed with heart disease, and who had participated in a study looking at the effects of medication on patients with heart disease induced by stress. They found heart health was different between the sexes, even though they were all affected by stress. After each participant underwent different stressful tasks, including a math test, a mirror tracing test, and recalling situations that made them angry, researchers threw them onto the treadmill. During the mental stress tests, and resting periods before and after the treadmill exercise, the researchers collected blood samples, and measured blood pressure and heart rate.

They found some significant differences. Men’s blood pressure fluctuated in response to their mental stress tests much more than women’s did, while women were more emotionally negative than men. During the mental stress tests, women had less blood flow to their heart, and showed an increase in blood clot formation compared to men. According to Harvard University Medical School, women are also more likely to show narrowing or stiffening of their arteries, which may explain the decreased blood flow under mental stress.

When heart disease is the cause of 600,000 deaths in the United States every year, and more than half of men’s deaths are from heart disease, it’s important to understand how the disease appears in both sexes. Men and women experience different symptoms but it wasn’t understood until now how differently stress impacts each gender. Stress tests are more reliable in detecting heart disease in women than men, and while high cholesterol or blood pressure is the first sign of danger, stress may be a sign of a worse outcome for women with heart disease.

"At this point, further studies are needed to test the association of sex differences in the heart's responses to mental stress and long term outcomes," Samad said. "This study also underscores the inadequacy of available risk prediction tools, which currently fail to measure an entire facet of risk, i.e. the impact of negative physiological responses to psychological stress in both sexes, and especially so among women."

Source: Samad Z. Journal of the American College of Cardiology. 2014.