Brain activity’ key in stress link to heart disease’
The effect of constant stress on a deep-lying region of the brain explains the increased risk of heart attack, a study in The Lancet suggests.
In a study of 300 people, those with higher activity in the amygdala were more likely to develop cardiovascular disease– and sooner than others.
Stress could be as important a risk factor as smoking and high blood pressure, the US researchers said.
Heart experts told at-risk patients should be helped to manage stress.
Emotional stress has long been linked with an increased risk of cardiovascular disease( CVD ), which affects the heart and blood vessels- but the style this happens has not been properly understood.
This study, led by a squad from Harvard Medical School, points to heightened activity in the amygdala- an area of the brain that processes feelings such as fear and rage- as helping to explain the link.
The researchers suggest that the amygdala signals to the bone marrow to render extra white blood cells, which in turn act on the arteries causing them to become inflamed. This can then cause heart attack, angina and strokes.
As a outcome, when stressed, this part of the brain appears to be a good predictor of cardiovascular events.
But they also said more research was needed to confirm this chain of events.
The Lancet research looked at two different surveys. The first scanned the brain, bone marrow, spleen and arteries of 293 patients, who were tracked for nearly four years to see if they developed CVD. In this time, 22 patients did, and they were the ones with higher activity in the amygdala.
The second very small survey, of 13 patients, looked at the relationship between stress levels and rednes in the body.
It found that those who reported the highest levels of stress had the highest levels of amygdala activity and more evidence of rednes in their blood and arteries.
Dr Ahmed Tawakol, lead author and associate professor of medicine at Harvard Medical School, told:” Our outcomes provide a unique insight into how stress may lead to cardiovascular illnes .
” This raises the possibility that reducing stress could render benefits that extend beyond an improved sense of psychological wellbeing.
The amygdalae are two almond-shaped groups of nuclei situated deep within the brainScience Photo Library
The amygdala is one of the most primitive parts of the brain linked to strong feelings, such as fear and anger.
What does the amygdala do ?
It’s the part of the brain that prepares you for battle or flight, becoming activated by strong emotional reactions.
The amygdalae( because there are two of them- one on both sides of the brain) are almond-shaped groups of cells situated deep within the medial temporal lobes of the brain.
In humans and animals, the amygdala is linked to responses to both fear and pleasure.
The term amygdala- which entails almond in Latin- was first used in 1819.
Dr Tawakol added:” Eventually, chronic stress could be treated as an important risk factor for cardiovascular disease, which is routinely screened for and effectively managed like other major cardiovascular illnes risk factors .”
Commenting on the research, Dr Ilze Bot, from Leiden University in the Netherlands, told more and more people were experiencing stress on a daily basis.
” Heavy workloads, job insecurity or living in poverty are circumstances that can result in chronically increased stress, which in turn can lead to chronic psychological disorder such as depression .”
Emily Reeve, senior cardiac nurse at the British Heart Foundation, told reducing the risk of heart illnes and stroke from stress usually focused on controlling lifestyle habits such as smoking, drinking too much alcohol and overeating- but this should change.
” Exploring the brain’s management of stress and discovering why it increases health risks of heart illnes will allow us to develop new ways of managing chronic psychological stress.
” This could lead to ensuring that patients who are at risk are routinely screened and that their stress is managed effectively .”