Even small, everyday stressors may be enough to diminish function of blood vessels in otherwise healthy people with depression, researchers report.
Their study shows that adults with depression who experienced stress in the previous 24 hours had worse endothelial function—a process that helps regulate blood flow—than those with depression alone.
The results help explain the links between stress, depression, and cardiovascular disease, and may help design future intervention and prevention strategies, says Lacy Alexander, associate professor of kinesiology at Penn State.
“This study could be a jumping-off point for looking into whether if people are taught more behavioral strategies in dealing with everyday stressors, maybe that could be protective for their cardiovascular health,” she says.
“For example, maybe mindfulness or cognitive behavioral therapy could be beneficial not just for young, healthy adults, but also for those who are at risk for cardiovascular disease.”
Three-way interaction
Previous research has linked chronic exposure to stress with the development of cardiovascular disease. But researchers say they don’t know the exact processes of how stress affects the body and contributes to it.
Because depression also links to cardiovascular disease, researchers wanted to better understand how stress, depression, and vascular function connect, says Jody Greaney, now an assistant professor at the University of Texas at Arlington, who led the study as a postdoctoral research fellow at Penn State.
“When I started studying how vascular function differs in adults with depression, it became clear that we had to consider the role of stress, as well,” Greaney says. “If you’re chronically stressed, you’re more likely to develop depression. It’s just impossible to tease those two apart. We wanted to look at the three-way interaction between stress, depression, and vascular function.”
Physiology and psychology
For the study, which appears in the Journal of the American Heart Association, researchers recruited 43 healthy adults who did not have cardiovascular disease, did not use tobacco products, and were recreationally active. The researchers also evaluated the participants for symptoms of depression.
On the day of the experiment, participants reported any stressors they had experienced in the previous 24 hours, including arguments with a friend or family member or a stressful event at work or school.
The researchers also measured endothelial function by inserting a tiny fiber under the skin of the participants’ arms. The fiber allowed them to apply a small amount of the drug acetylcholine, which then affected the blood vessels in an area about the size of a dime. The researchers looked at how the drug affected the endothelial function in those vessels.
In addition to the link between stress and worse endothelial function, the researchers found other symptoms associated with depression.
“Adults with depression also experienced more stress and rated it as being more severe than healthy non-depressed adults, which confirms the link between stress and depression,” Greaney says.
“Additionally, adults with depression may have worse vascular function in general, although endothelial function was worse when depression and stress were combined.”
In addition to being helpful for designing future prevention and intervention efforts, the results help underline the importance of the psychological aspects of certain conditions, Greaney says.
“As a physiologist, I’m used to drilling down into the specific mechanisms of vascular function without ever considering a psychological profile of that person. But this study would tell you that’s critically important to consider—the interplay between physiology and psychology.”
In the future, Greaney said she hopes to continue researching a more comprehensive assessment of stress and additional measures of vascular function.
Additional researchers from Penn State contributed to the study. The National Institutes of Health, the National Center for Advancing Translational Sciences, and the American Heart Association supported this work.
Source: Penn State
