Can a burst of anger take a toll on the heart?
Previous research has suggested there’s a link between an acute episode of anger and an increased risk of heart attack. Researchers from Columbia University Irving Medical Center, Yale School of Medicine, St. John’s University in New York and other institutions wanted to tease out why.
To answer that question, they’d need to make some people angry.
The investigators recruited 280 healthy young adults and randomized them into four groups: a control group that counted out loud for eight minutes and maintained a neutral emotional state, and groups who recalled events that made them angry, sad or anxious. Before they began, and at intervals for 100 minutes afterward, the researchers took blood samples and measurements of blood flow and pressure.
The findings, published Wednesday in the Journal of the American Heart Association, show that anger may indeed affect the heart because of how it impairs blood vessel function.
The researchers found blood vessels’ ability to dilate was significantly reduced among people in the angry group compared with those in the control group. Blood vessel dilation wasn’t affected in the sadness and anxiety groups.
Dilation can be regulated by endothelial cells, which line the insides of blood vessels. By dilating and contracting, blood vessels slow down or increase the flow of blood to the parts of the body that need it.
Further tests revealed that there was no damage to the endothelial cells or to the body’s ability to repair any endothelial cell damage.
The only issue was the dilation, the study found. Impairment of how blood vessels dilate is an early marker for atherosclerosis, which is the buildup of fats and cholesterol, called plaque, on artery walls that make the arteries stiff. Atherosclerosis can lead to coronary heart disease, heart attack, stroke and kidney disorders.
“That is why endothelium-dependent vasodilation is an important mechanism to study,” said co-author Andrea Duran, an assistant professor of medical sciences at Columbia University Irving Medical Center, using the medical terminology for the impairment seen in the study.
The results of the study could help physicians persuade their patients who have heart disease and anger problems to manage their anger, through yoga, exercise, cognitive behavioral therapy or other established techniques, said Dr. Holly Middlekauff, a cardiologist and a professor of medicine and physiology at UCLA’s David Geffen School of Medicine.
“It’s not widely known or widely accepted that anger does precipitate heart attacks,” said Middlekauff, who wasn’t involved with the study. “This study offers a biological plausibility to that theory, that anger is bad for you, that it raises your blood pressure, that we’re seeing impaired vascular health.”
And that may get some patients’ attention, she added.
Duran cautioned that the laboratory study is a foundational study and that further research is needed. For example, scientists don’t know exactly how anger impairs blood vessel dilation. “That would be for a future study,” she said.
In the paper, the researchers suggested several factors could be at work, including changes caused by stress hormones, increased inflammation and activation of the autonomic nervous system, which regulates involuntary processes like heart rate, blood pressure and breathing.
In addition, the researchers intentionally selected participants who were healthy, without heart disease or other chronic conditions that could confound the results. While that is a strength of the study, it also is a limitation, because the findings may not apply to older people who are ill.
“This was just the first step,” said Rebecca Campo, a psychologist and program director at the National Heart, Lung and Blood Institute, which funded the study.
Future research should look at “populations with cardiovascular disease, with diabetes and at people who live in rural settings and ethnic and racial minorities.”
Middlekauff said the biggest limitation of the study is that it looked at one bout of provoked anger.
“I’d like to see a study of a group of chronically angry people and see what their vascular function is,” she said.
