Stress endangers the health of our heart
Stress is not good for the human heart. This statement is probably well known. Researchers are now investigating why stress affects our heart's health. They found that fear and stress are linked to a specific region of the brain. This is also involved in the development of strokes and heart diseases.
The researchers at Massachusetts General Hospital found that activity in the so-called amygdala can increase the risk of subsequent cardiovascular diseases. Anxiety and stress affect this part of the brain. The doctors published the results of their study in the journal "The Lancet".
Study: The amygdala is caused by stress
The results of the current study lead to several new findings, say the experts. One of them is that the amygdala is affected by stress. This may increase the risk of a subsequent cardiovascular disease, explains author Dr. Ahmed Tawakol from Massachusetts General Hospital. The amygdala is a critical component of the so-called stress network in the brain. This region becomes metabolically active during times of stress, the author explains. The current investigation could reveal new ways to reduce stress-related cardiovascular diseases, the researchers hope.
Cardiovascular diseases are the leading cause of death worldwide
According to the World Health Organization (WHO), so-called cardiovascular diseases are the leading cause of death in men and women around the world. In the United States alone, more than a third of adults suffer from at least one type of cardiovascular disease, and heart disease is the leading cause of death in this country too.
Stress leads to increased activity of cells in the bone marrow and spleen in animals
The current study included 293 adult subjects. Between 2005 and 2008, they underwent various so-called PET and CT scans at Massachusetts General Hospital in Boston. These scans determined brain activity, bone marrow activity, spleen activity, and inflammation in the arteries of the heart, the scientists explain. Some animal studies have already suggested that stress can lead to increased activity of cells in the bone marrow and spleen.
Subjects were medically monitored for two to five years
The researchers monitored the health of the patients for a period of two to a maximum of five years. During this time, 22 of the subjects suffered a so-called cardiovascular disease event. These include, for example, strokes, heart attacks or heart failure, the experts explain.
Higher amygdala activity increases risk of cardiovascular events
After analyzing the scans and cardiac health of all patients, the scientists found that increased amygdala activity was associated with a higher risk of cardiovascular events. Lonely people are also more likely to have heart disease, the authors say in the study.
Higher amygdala activity associated with inflammation in the arteries
The connection between the amygdala and cardiovascular diseases remained significant even after considering the risk from other cardiovascular risk factors such as smoking, diabetes or hypertension, the doctors explain. The researchers also found that amygdala activity was associated with increased bone marrow activity and inflammation in the arteries.
More research is needed
Stress can activate the amygdala, which leads to additional immune cell production by the bone marrow. This process in turn affects the arteries and can cause inflammation, which can lead to a heart attack or a stroke, for example, the doctors explain. More research is now needed to replicate the results across a larger sample of patients. (as)