New York, Jan 12: Sounding an alarm bell for those who take unnecessary stress at workplace or at home, researchers have now linked chronic psychosocial stress with an heightened risk of developing heart disease and stroke.
According to the team from Massachusetts General Hospital and Harvard Medical School, heightened activity in the amygdala -- a region of the brain involved in stress -- can lead to cardiovascular disease in humans apart from established causes like smoking, high blood pressure and diabetes.
Previous research has also shown that the amygdala is more active in people with post-traumatic stress disorder (PTSD), anxiety and depression but before this study, no research had identified the region of the brain that links stress to the risk of heart attack and stroke.
"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 from Massachusetts General Hospital and Harvard Medical School.
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 risk factors, Dr Tawakol added in a paper published in the prestigious journal The Lancet.
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.
The patients were then tracked for an average of 3.7 years to see if they developed cardiovascular disease.
In this time, 22 patients had cardiovascular events including heart attack, angina, heart failure, stroke and peripheral arterial disease.
Those with higher amygdala activity had a greater risk of subsequent cardiovascular disease and developed problems sooner than those with lower activity.
The researchers also found that the heightened activity in the amygdala was linked to increased bone marrow activity and inflammation in the arteries, suggesting this may cause the increased cardiovascular risk.
Although more research is needed to confirm that stress causes this chain of events as the study was relatively small, these findings could eventually lead to new ways to target and treat stress-related cardiovascular risk, the researchers noted.
"These clinical data establish a connection between stress and cardiovascular disease, thus identifying chronic stress as a true risk factor for acute cardiovascular syndromes," wrote Dr Ilze Bot, Leiden Academic Centre for Drug Research, Leiden University, The Netherlands, in a linked comment.