Stress ups coronary heart disease risk by 27 per cent

Researchers from the Columbia University Medical Center analysed six studies in which participants were asked questions on how stressed do they feel or how often they are stressed.

Respondents scored either high or low; researchers then followed them for an average of 14 years to compare the number of heart attacks and CHD deaths between the two groups.

"While it is generally accepted that stress is related to heart disease, this is the first meta-analytic review of the association of perceived stress and incident CHD," said senior author Donald Edmondson, assistant professor of behavioural medicine at CUMC.

"This is the most precise estimate of that relationship, and it gives credence to the widely held belief that general stress is related to heart health," Edmondson said in a statement.

"In comparison with traditional cardiovascular risk factors, high stress provides a moderate increase in the risk of CHD - eg, the equivalent of a 50 mg/dL increase in LDL cholesterol, a 2.7/1.4 mmHg increase in blood pressure or smoking five more cigarettes per day," Edmondson added.

"These findings are significant because they are applicable to nearly everyone," said first author Safiya Richardson.

Coronary heart disease (CHD), also called coronary artery disease, is a narrowing of the small blood vessels that supply blood and oxygen to the heart. It is caused by a buildup of plaque in the arteries, which can lead to hardening of the arteries, or atherosclerosis.

The researchers did further analysis to try to learn what might underlie the association between stress and CHD. They found that while gender was not a significant factor, age was.

The people in the studies were between the ages of 43-74; among older people, the relationship between stress and CHD was stronger.

"While we do not know for certain why there appears to be an association between age and the effect of perceived stress on CHD, we think that stress may be compounding over time. For example, someone who reports high perceived stress at age 60 may also have felt high stress at ages 40 and 50, as well," Edmondson said.

The study was published in the American Journal of Cardiology.