NIH-funded clinical trial links frequent anger to increased risk of heart disease

May 14, 2024
Findings demonstrate impairment of blood vessel function; may lead to heart attack, stroke.

Recurring feelings of anger may increase a person’s risk of developing heart disease by limiting the blood vessels’ ability to open, according to a new study supported by the National Institutes of Health.

The study, published in the Journal of the American Heart Association (JAHA), shows for the first time that anger is linked to this vascular impairment — a precursor to the kind of long-term damage that can lead to heart attack and stroke.

While a brief spurt of occasional anger is normal and generally has a benign impact on the heart, it is recurring or frequent anger the researchers said raises concern.    

For the randomized, controlled study, researchers recruited 280 healthy adults aged 18 to 73 years within the New York City area. The participants were free of cardiovascular disease and without risk factors such as history of hypertension, diabetes, and lipid imbalances, according to self-reported survey data. All participants were non-smokers, medication-free, and without a history of diagnosed mood disorders.  

The researchers measured blood flow changes in the blood vessels of each participant’s dominant arm. They then randomly assigned each to a task to elicit either anger, anxiety, sadness, or a neutral emotional state.

Using standard methods for laboratory experiments like these, the researchers asked the participants in the anger and anxiety groups to talk for 8 minutes about personal experiences that had evoked those emotions. Those in the sadness group read aloud for 8 minutes a series of brief statements designed to elicit sadness. The control group counted numbers out loud for 8 minutes to induce an emotionally neutral state. When each group was done, researchers measured blood vessel changes again — immediately at the end of the task, and after 3, 40, 70, and 100 minutes.
    
The researchers found that the ability of the blood vessels to dilate was significantly reduced among participants in the anger group compared to those in the control group. This vessel impairment was sustained up to 40 minutes after the initial recall event that triggered the anger and decreased afterward. In contrast, the blood vessels of those in the anxiety and sadness groups were not affected.

Prior studies have shown that impaired blood vessel dilation is a precursor to the development of atherosclerosis — the buildup of fatty deposits inside the vessel walls — which in turn can lead to heart disease, including heart attack and stroke.

NIH release