We’ve all heard some rendition of it before, usually in the midst of an argument: “Stop it before your father has a heart attack.” While the warning is sometimes enough to calm things down, chances are none of us ever really believe it will happen — until it does. Now, a new study confirms what most of us have believed: Intense bouts of anger can certainly trigger a heart attack.

Now that’s not to say the next time you get dad — or anyone — angry, they’re going to have a heart attack. But researchers at the University of Sydney and Royal North Shore Hospital found people who regularly reached above a certain level of anger were 8.5 times more likely to a heart attack (myocardial infarction, or MI) within two hours of becoming enraged. This is “most likely the result of increased heart rate and blood pressure, tightening of blood vessels, and increased clotting, all associated with triggering heart attacks,” said Dr. Thomas Buckley, a senior lecturer at the university, in a press release.

While stress is one thing to worry about when it comes to cardiovascular and mental health risks, anger and anxiety are on an entirely other level, amplifying stress’ effects. People who stay angry or anxious for extended periods of time are more likely to have difficulty coping with smaller aggravations. De-stressing becomes harder, and having a good, fun time might as well be impossible. It can also lead to feelings of remorse, guilt, and regret among those who realize the error of their ways. All of this obviously affects mental health, but it also affects physical health, as evidenced by the current study.

For the study, Buckley and his team looked to patients admitted at the Royal North Shore Hospital in Sydney, who were suspected of having a heart attack. Of the 687 patients first assessed, 313 enrolled after confirmation through a coronary angiogram that they had indeed suffered a heart attack. Each patient responded to a questionnaire asking about their anger over the 48 hours prior to having a heart attack. They were asked rate their anger on a seven-point scale with 1 defined as “calm” and 7 as “enraged, out of control, throwing objects, hurting yourself or others.” They also used level 5 as the threshold for acute anger, defined as “very angry, body tense, maybe fists clenched, ready to burst.”

They found that seven of the participants had reached an anger level of at least 5 within the two hours before heart attack symptoms developed, while another reached the same level within the four hours prior to symptoms. Meanwhile, two patients reached an anger level of 4 — moderately angry, so hassled it shows in your voice — within the two hours before symptoms, while three reached the same level within four hours. The researchers included the frequency with which patients reported getting angry into their calculations for determining heart attack risk, thus arriving at 8.5 times greater risk among those who reached a level 5 or higher.

The findings add to a growing “acceptance of the role of psychological factors, both acute and chronic, in the onset of acute MI, sudden cardiac death, and stroke.” Considering constant anger can lead to symptoms of depression, and depression itself can lead to heart problems, there’s a good chance that, when combined with acute anger, a person’s risk of a heart attack will worsen. For this, the researchers urge health care providers to include assessments for anger and anxiety when managing or determining risk of heart disease in their patients. They also suggested anger management and avoidance of intense situations. As for everyone else, it could be worth sucking up any pride in an effort to prevent a trip to the emergency room.

Source: Buckley T, Soo Hoo SY, Fethney J, et al. Triggering of acute coronary occlusion by episodes of anger. European Heart Journal: Acute Cardiovascular Care. 2015.