According to recent data, depression may have more severe consequences than previously thought. Compared to people who are not depressed, those with a mood disorder could be two times as likely to suffer a heart attack.

To date, this process has not been clearly understood. A novel investigation led by Concordia University has discovered that recovery time following exercise is slower for individuals who suffer from depression than for those who are non-depressed. The study is published in the journal Psychophysiology.

Findings from the investigation indicate that a dysfunctional biological stress system is active among individuals who are depressed. The study warns that it is vital that patients suffering from major depression be tested for cardiovascular disease.

First author, Jennifer Gordon, who is a PhD candidate at McGill University, explains:

“There have been two competing theories as to why depression is linked to cardiovascular disease. Depressed people may have poorer health behaviors, which may in turn lead to heart problems.

The other possibility is physiological: a problem with the stress system known as the fight or flight response. Our study was the first to examine the role of dysfunctional fight or flight response in depression in a large population.”

The study, carried out by Concordia in association with the Montreal Heart Institute, McGill University, the Hôpital Sacré-Coeur de Montréal, the Université du Québec à Montréal and the University of Calgary, enrolled a total of 886 individuals, who were on average 60 years old, to participate in the investigation.

Around 5% of the participants were diagnosed with a major depressive disorder. After they all underwent a stress test, their blood pressure and heart rate were recorded. The researchers then compared recovery blood pressure levels and heart rates between those who were depressed with non-depressed participants.

Senior author, Simon Bacon, a professor in the Concordia University Department of Exercise Science and an investigator at the Montreal Heart Institute, said:

“We found that it took longer for the heart rate of depressed individuals to return to normal. Heart rate recovery from exercise is one way to measure the fight or flight stress response. The delayed ability to establish a normal heart rate in the depressed individuals indicates a dysfunctional stress response. We believe that his dysfunction, can contribute to their increased risk of heart disease.

The take-home message of this study is that health care professionals should not only address the mental disorder, but also the potential for heart disease in patients who are suffering from major depression. Both of these health issues should be treated to minimize risk of severe consequences.”

Written by Grace Rattue