A new study has shown that anger, anxiety and depression can not only affect how your heart functions, but also directly increase your risk for heart disease.
Strokes and heart attacks happen as a result of progressive damage to blood vessels that supply the heart and brain. This process is known in medical terms as atherosclerosis.
Atherosclerosis progresses when there are high levels of specific chemicals known as pro-inflammatory cytokines. Health experts believe that persistent, uncontrollable levels of stress increase risk for atherosclerosis and cardiovascular disease by triggering negative emotions that raise the levels of these pro-inflammatory chemicals in the body.
To investigate the underlying mechanism of this process, study researchers started with the observation that many of the same brain areas involved in emotion are also involved in sensing and regulating levels of inflammation.
They theorized that brain activity linked to negative emotions - specifically, to efforts made to control negative emotions - would be connected to physical signs of risk for heart disease.
During the study, 157 healthy adult volunteers were asked to regulate their emotional reactions to unpleasant images while their brain activity was measured with functional imaging. Further, study researchers also scanned their arteries for signs of atherosclerosis to assess heart disease risk and measured levels of inflammation in their blood.
They found that individuals who show greater brain activation while managing their negative emotions also had higher blood levels of interleukin-6, one of the human body's main pro-inflammatory chemicals. Many of these individuals also had thicker carotid artery walls, a typical marker of atherosclerosis.
In other words, inflammation levels accounted for the link between signs of atherosclerosis and brain activity patterns seen during emotion management. These findings were significant even after controlling for age, gender, smoking and other heart disease risk factors.
These new findings lend support to the popular belief that emotions are connected to heart health. They also suggest that brain-based prevention and intervention efforts may be able to improve heart health and protect against heart disease.
As scientists identify the mechanisms by which the brain and body are linked, they hope to be able to break the cycle by which emotional stress caused by anger, anxiety and depression impairs heart health.