Doctors have long believed that chronic stress causes strokes and heart attacks, but they’ve not been able to work out why, until now.
A new study has found a link between cardiovascular disease and the part of the brain that manages stress, the amygdala.
It raises hopes that some strokes and heart attacks could be prevented by stress management.
The amygdala was once key to humans’ survival. If you’re in harm’s way, it prompts bone marrow to form white blood cells, which can repair damage.
But the study suggests that chronic anxiety causes the over-production of the cells, forming a plaque in the arteries that can cause heart disease.
“Our results provide a unique insight into how stress may lead to cardiovascular disease. This raises the possibility that reducing stress could produce benefits that extend beyond an improved sense of psychological wellbeing,” said lead author Dr Ahmed Tawakol, Massachusetts General Hospital and Harvard Medical School. “
The thinking is that chronic stress could be monitored and managed just like any other risk factor for cardiovascular disease, such as smoking, high blood pressure and diabetes.
In the study, 293 patients were given a combined PET/CT scan to record their brain, bone marrow and spleen activity and inflammation of their arteries.
They were then monitored for more than three years on average, during which 22 patients suffered heart attacks, angina, heart failure, strokes or peripheral arterial disease.
The scientists think the amygdala might also contribute to heart disease in other ways beyond triggering white blood cells, as the process didn’t account for the full link. They now want to conduct a larger study.
Commenting on the research, which was published in the Lancet, Dr Ilze Bot, Leiden Academic Centre for Drug Research, said: “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 disorders such as depression.”
“These clinical data establish a connection between stress and cardiovascular disease, thus identifying chronic stress as a true risk factor for acute cardiovascular syndromes, which could, given the increasing number of individuals with chronic stress, be included in risk assessments of cardiovascular disease in daily clinical practice.”