A group of Canadian investigators says it's found a solution to a thorny challenge in the biomarker world. By measuring the level of cortisol--a key biomarker for stress--in hair follicles, they can now track the body's stress levels over a potentially long period of time. And chronic stress is a well known risk indicator for heart attacks and cardiovascular disease.
Researchers have already been able to measure cortisol in various body fluids, but those indicators are just snap shots of cortisol at one particular point. The researchers tracked cortisol levels as the hair follicle grew out, giving them a steady readout--something like measuring the age of a tree by counting the annual circles marked in its trunk.
The scientists compared a 3-cm section of hair taken from men who suffered heart attacks with a group who had been hospitalized for other conditions. This new study, printed in the online version of Stress, determined that cortisol was actually a better biomarker for heart attacks than classic risk factors like smoking and blood pressure.
"We felt that stress was a minor factor compared to the other known risk factors for heart disease, but we didn't think it would be the strongest of them all," says study researcher Stan Van Uum, an associate professor of medicine at the Schulich School of Medicine & Dentistry at the University of Western Ontario in London, Canada.