Traditional Heart Risk Factors Outdo Biomarkers
Researcher says newer measures not ready for primetime
WEDNESDAY, Dec. 20, 2006 (HealthDay News) -- The sophisticated biomarkers for cardiac risk that have enthralled researchers in recent years don't add much diagnostic power to such traditional risk factors as blood cholesterol levels, smoking, blood pressure and obesity, a new study finds.
"Our results indicate that, at least for clinical use, they are not ready for prime time," said study author Dr. Thomas J. Wang, an assistant professor of medicine at Harvard University and a member of Massachusetts General Hospital's cardiovascular division. The report is published in the Dec. 21 issue of the New England Journal of Medicine.
Wang and his colleagues followed 3,209 participants in the Framingham Heart Study for a decade, measuring biomarkers that included C-reactive protein, homocysteine, urinary albumin, fibrinogen and natriuretic peptides.
While those measurements did provide indicators of increased risk of cardiovascular disease, "a lot of biomarkers don't seem to add a great deal once you take the standard risk factors into account," Wang said.
But research on those biomarkers should continue, because "there very well could be subgroups of people in which it would be useful to measure biomarkers," Wang said. "We need further data on that question."
Another reason for continuing research is that "there are studies that suggest that treating people to lower these biomarkers improves clinical outcome," he said.
But the bottom line is that "widespread use of biomarkers is not indicated at this time for clinical purposes," Wang said.
"The message in the article is that the cycle of enthusiasm and hope that we have found the holy grail has been shot down," said James H. Ware, dean for academic affairs at the Harvard School of Public Health, who wrote an accompanying commentary.
Researchers have tended to hope that a newly discovered biomarker "might be a great advance in the ability of a doctor to take individual patients and make a diagnosis," Ware said. "But a lot of these things don't have much use as diagnostic tools."
"People will be more cautious as new biomarkers emerge," he added.
But research should continue because "diseases like cardiovascular disease are very complicated, multi-factorial phenomena," Ware said. "There is not one pathway that leads to impairment of the heart, so a description of it is bound to be complicated."
One useful lesson of the study is that "our data provide a useful reminder that traditional risk factors are very important," Wang said. "They set the bar very high in terms of the knowledge they give us. It takes a fair amount to improve on what we already have."
The known risk factors for cardiovascular disease are listed by the American Heart Association.