High sensitivity C-reactive protein in cardiovascular risk assessment. CRP mania or useful screening?

Abstract

Elevated level of the acute phase reactant C-reactive protein (CRP) is a very sensitive marker of acute inflammatory reactions. Using high sensitivity assays for CRP, recent observations indicate that slightly elevated CRP levels which would be in the normal range of conventional assays are a novel marker for an increased risk for cardiovascular events, especially coronary artery disease and myocardial infarction. Various large scale prospective trials including the Physicians' Health Study and the Women's Health Study revealed that slightly increased hsCRP levels at base line in apparently healthy persons are associated with a 2-fold increase in the risk of a future myocardial infarction. The predictive value of hsCRP was found to be independent from classic risk factors, in particular from elevated serum cholesterol. An increase in hsCRP levels was also associated with a higher risk to develop peripheral artery disease and with a faster progression of carotid artery disease. Until now, treatment with HMG-CoA reductase inhibitors (statins) has been found to be the only medication to consistently decrease hsCRP levels, although by about 15% only. Despite the association of elevated hsCRP levels with future cardiovascular events, routine measurement of hsCRP for cardiovascular risk assessment is currently not recommended because of its low accuracy, the lack of a clear cut-off point for elevated hsCRP levels and the lack of an absolute predictive value. So far, hsCRP remains an interesting potential risk marker for cardiovascular disease whose definite relevance remains to be established.