Measurement of known biomarkers of cardiovascular (CV) disease slightly improves the ability to predict future heart attack or stroke in healthy individuals, but not enough to change preventive therapies, according to a study in the July 1 issue of the Journal of the American Medical Association.
"While there currently does not appear to be a role for routine use of biomarkers in screening for cardiovascular risk, our data do not exclude a role for biomarkers in selected patients," said the study's senior author Thomas Wang, MD, from the Massachusetts General Hospital (MGH) Heart Center in Boston. "We're still optimistic that new technologies will lead to the discovery of biomarkers that could help us move toward offering truly personalized cardiovascular risk prediction."
The investigators focused on two biomarkers that have been extensively studied in CV disease -- C-reactive protein (CRP) and N-terminal pro-B-type natriuretic peptide (N-BNP) -- and four that recently have been identified as relating to CV risk -- Cystatin C, Lp-PLA2, MR-proADM and MR-proANP.
They enrolled more than 5,000 participants in the Malmö Diet and Cancer Study, an ongoing prospective study based at Lund University in Lund, Sweden, for whom both complete conventional CV risk data and plasma samples were available. The researchers analyzed plasma levels of the six biomarkers in samples taken when participants entered the study and then, using a personal identification number assigned to each Swedish citizen, searched for information on subsequent coronary and CV events in databases on hospital discharges, strokes and causes of death occurring over a period averaging almost 13 years.
The researchers found that two of the studied biomarkers -- N-BNP and MR-proADM -- significantly improved the prediction of coronary events, defined as a heart attack or death from ischemic heart disease. Also, N-BNP and CRP improved the prediction of CV events, which are coronary events plus strokes.
However, Wang and colleagues noted that when the ability of biomarkers to move individual patients into higher- or lower-risk categories was analyzed, the potential impact on treatment decisions was minimal.
"Since choice of therapies may depend on the risk category a patient falls into, moving patients between risk categories could lead to a change in therapy," explained co-author Christopher Newton-Cheh, MD, MGH Heart Center. "While there was more category movement among participants initially classified as intermediate-risk, that resulted primarily from movement to lower risk levels, so we still need to find biomarkers that can make a clinically significant difference in predicting cardiovascular risk."
Wang and Newton-Cheh are both assistant professors of Medicine at Harvard Medical School in Boston.