Feeling stressed? Research shows how stress can lead to heart attacks and stroke
Feeling constantly stressed could increase your risk of heart and circulatory disease, according to news coverage. But is there truth behind the headlines?
Feeling stressed all the time could raise your risk of heart attack and stroke, according to a new study.
The Lancet study, which has garnered media attention, links stress to heart and circulation disease in adults for the first time.
Stress increases heart and circulatory disease risk and brain activity in the emotional processing area.
The researchers, from Harvard University, suggested stress could be as important a risk factor as smoking or high blood pressure.
The research was made up of two studies.
In the bigger study of 293 patients, brain scans showed that the amygdala, which deals with stress, stimulates the bone marrow to create more white blood cells when agitated.
This in turn causes the arteries to become inflamed. We know inflammation causes heart attacks, angina, and strokes.
When you experience stress, the amygdala sends a distress signal to your hypothalamus, which then communicates this to the rest of your body so it is ready to fight or for flight.
In the first (larger) study, the researchers found that the link between activity in the amygdala and later heart events and stroke was due to increased bone-marrow activity and arterial inflammation.
In the second (smaller) study, highly stressed persons with elevated amygdalar activity had higher arterial inflammation. People who rated themselves as more stressed were also more likely to have higher levels of activity in the amygdala.
Mice had shown these mechanisms.
researchers stated.
In the first (bigger) study, greater bone-marrow activity and vascular inflammation linked amygdala activity to eventual cardiac events and stroke.
In the second (smaller) study, highly stressed persons with elevated amygdalar activity had higher arterial inflammation. People who rated themselves as more stressed were also more likely to have higher levels of activity in the amygdala.
These processes had been previously shown in mice, but never before in humans, the researchers said”Exploring the brain’s management of stress and discovering why it increases the risk of heart disease will allow us to develop new ways of managing chronic psychological stress.
“This may ensure at-risk folks are continuously evaluated and stress managed properly,” she said.
Limitations
The study was relatively small (293 people) Of these, 22 people experienced heart or circulatory events during follow up – so the findings are based on quite a small number of people. The broader study used data from cancer screenings. Although participants had to be cancer-free for at least one year before brain scans, this could have altered the results.
For the smaller study 13 people were chosen who had an ‘increased burden of chronic stress (i.e. history of post-traumatic stress disorder)’ the report says. Yet, most UK stressors are not as severe.
Overall, the coverage was quite accurate.
Two studies provided proof, albeit some media didn’t make it clear.
The Telegraph’s headline ‘Scientists finally discover how stress causes heart attacks and strokes’ is misleading, as the researchers say they have established a ‘link’ between brain activity in a certain area and subsequent cardiovascular disease, not a cause and effect. This study needs more research to conclude.
