This is the VOA Special English Health Report.
Cardiovascular disease is the world's leading cause of death. It includes heart attack, stroke and high blood pressure.
Over the years, researchers have identified several substances in the blood that can serve as what they call cardiac biomarkers. These are used to measure the presence and development of cardiovascular disease.
A team from Massachusetts General Hospital and Sweden's Lund University studied how effective the biomarkers are as predictors. Thomas Wang at the Mass General Heart Center was the senior author of the study.
THOMAS WANG: "What we found is that, in fact, even after measuring those additional biomarkers that there wasn't a great deal of benefit in terms of understanding who was more likely to develop heart disease"
Doctor Wang says they did identify some combinations of biomarkers that improved predictions of heart attacks and strokes. But, he says, there is not enough evidence to justify measuring these in everybody.
THOMAS WANG: "It's still possible that in certain patients, measuring these biomarkers would be helpful. There are some patients for whom physicians are really on the fence about whether to give one therapy or another. And in those cases having the biomarker which adds a little bit of information may be helpful in terms of decision making. But for the majority of patients, having the information of the biomarker probably wouldn't make a difference."
Doctor Wang hopes future research will discover biomarkers that are better able to predict the risk of cardiovascular disease. But for now, he says, doctors should depend on traditional risk factors. These include a history of high blood pressure, high cholesterol, tobacco use, diabetes, obesity, physical inactivity or poor nutrition.
A separate study found no support for a theory that a biomarker called C-reactive protein causes heart disease. Earlier research suggested that the more of the protein in people's blood, the more likely they are to develop heart disease. The new study confirmed a link, but did not find evidence that the C-reactive protein causes the disease.
Both studies appeared in the July first issue of Journal of the American Medical Association.
The World Health Organization estimates that cardiovascular disease killed seventeen and a half million people in two thousand five. That was thirty percent of all deaths. Eight out of ten happened in low and middle income countries. At current growth rates, the W.H.O. expects the number to reach twenty million by two thousand fifteen.
And that's the VOA Special English Health Report, written by June Simms. I'm Steve Ember.