Researchers found that in the 2 hours after a period of intense anger, the risk of heart attack may increase by 8.5 times.
Conducted by researchers from the University of Sydney in Australia, the study also reveals that this increased risk of heart attack, or myocardial infarction (MI), lasts for 2 hours following an episode of intense anger.
The link between anger and increased risk of heart attack is not new. In March 2014, a study by researchers from the Harvard School of Public Health in Boston, MA, suggested anger outbursts could raise the risk of heart attack, stroke and other cardiovascular events.
"Our findings confirm what has been suggested in prior studies and anecdotal evidence, even in films - that episodes of intense anger can act as a trigger for a heart attack," says lead author of this latest study Dr. Thomas Buckley, of the Sydney Nursing School at the University of Sydney.
In the US, around 735,000 people have a heart attack each year, and around 525,000 of these are first heart attacks.
Common risk factors for heart attack include high blood pressure, high cholesterol levels and smoking. But increasingly, researchers are investigating how psychological factors can trigger heart attack.
Episodes of anger, anxiety may increase heart attack risk by more than nine-fold
To reach their findings, which are published in the European Heart Journal: Acute Cardiovascular Care, Dr. Buckley and his team recruited 313 participants with acute coronary occlusion - a blockage in an artery that supplies the heart muscle with blood, normally caused by thrombosis or atheroma.
All participants had been admitted to a primary angioplasty center in Sydney between 2006 and 2012 with a suspected heart attack.
In the 4 days following admission, participants were questioned about their activities in the 48 hours prior to onset of symptoms. They were asked to rate their levels of anger during these 48 hours on a scale of 1-7, with 1 indicating "calm" and 7 indicating "enraged, out of control, throwing objects, hurting yourselves or others."
The study reveals that patients who experienced periods of anger at scale 5 (indicating "very angry, body tense, clenching fists or teeth, ready to burst") or above in the 48 hours prior to onset of symptoms were 8.5 times more likely to have a heart attack in the 2 hours after an outburst.
In addition, the team found that individuals who experienced high levels of anxiety in the 48 hours before symptom onset were 9.5 times more likely to have a heart attack within the following 2 hours.
Dr. Buckley says episodes of anger or anxiety can cause increased heart rate, high blood pressure, narrowing of blood vessels and increased clotting, all of which can be heart attack triggers.
Commenting on their findings, the researchers say:
"This study adds to the small, but growing, body of evidence linking acute emotional triggers with onset of MI. Future studies identifying the most vulnerable during times of emotional exposure may improve predictive models for when an MI will occur and inform future novel preventative therapies."
Senior study author Prof. Geoffrey Tofler, of Sydney Medical School at the University of Sydney, says these findings also suggest that when treating people at high risk of heart attack - such as patients with heart disease - their frequency of anger and anxiety should be considered.
What can be done to prevent anger- or anxiety-induced heart attack?
Prof. Tofler says stress reduction training to reduce frequency and intensity of anger episodes could be a useful strategy for preventing anger- or anxiety-induced heart attack, as could avoiding activities that trigger intense reactions - such as angry confrontation.
He notes that improving overall general health by reducing risk factors associated with heart attack - such as high blood pressure, smoking and high cholesterol levels - is also a good preventive strategy.
For individuals at high risk of heart attack, Prof. Tofler says there is a possibility that the use of medication such as aspirin or beta-blockers at the time of an episode of anxiety or anger could reduce heart attack risk, though he says this is something he and his colleagues are currently investigating.
"Our message to people is they need to be aware that a burst of severe anger or anxiety could lead to a coronary event, so consider preventative strategies where possible," he adds.