Depression, anxiety and chronic stress increase the risk for heart and brain health complications, according to two studies to be presented at the American Heart Association’s scientific sessions in Philadelphia, USA.

Mental health conditions may be known to increase risks for poor heart health, however new research examines the mechanism by which a person’s mental state affects their heart health, a mechanism that is not fully understood.

The research examined data for more than 71,000 adults, with an average age of 49 years, from December 2010 to December 2020. The scientists, led by Giovanni Sivieri, a researcher at the Cardiovascular Imaging Research Center at Massachusetts General Hospital and Harvard Medical School, found that study participants who had previously been diagnosed with with anxiety or depression developed a new risk factor an average of six months earlier than those without depression or anxiety. It found that depression and anxiety increased the risk of a major cardiovascular event, such as a heart attack or stroke, by about 35%. In addition, people with a higher genetic predisposition to stress developed their first cardiovascular risk factor an average of a year and a half earlier than people without the genetic marker.

The researchers argue that depression and anxiety can cause brain changes that trigger knock-on effects in the body; such as increased inflammation and fat deposition, and encourage people with depression or anxiety to get more frequent screening for cardiovascular risk factors such as high blood pressure, high cholesterol and type 2 diabetes.

In a second survey evaluated data on 2,685 adults without existing cardiovascular disease with a mean age of 48 years. Participants were followed for an average of 12.4 years. Accumulated stress was found to be associated with a 22% increased risk of atherosclerosis, in which plaque builds up in the arteries reducing adequate blood flow. It is also associated with a 20% increased risk of total cardiovascular disease, including coronary heart disease and heart failure.

In addition, accumulated stress was found to be higher among women, those aged 18-45, self-identified black or Hispanic adults, those with lower income and education, and those who reported racial/ethnic discrimination and lack of health insurance .

Ongoing stress, the analysis found, increased the risk of poor heart and brain health in two ways: by directly affecting physical well-being, but also by increasing bad lifestyle habits such as smoking and being sedentary, which in turn in turn lead to reduced cardiovascular health.