Narrative review: Assessment of C-reactive protein in risk prediction for cardiovascular disease

Some experts propose C-reactive protein (CRP) as a screening tool for prediction of cardiovascular disease (CVD). Many epidemiologic studies show positive associations between elevated CRP levels and incident CVD. Assessment of the value of new prognostic tests, however, must rely on understanding of test characteristics rather than on associations measured by relative risks. In the case of CRP, test characteristics must be judged in the context of currently available CVD risk prediction algorithms. In this review of literature published before January 2006, the authors describe what is known about the additional utility of CRP in risk prediction. They find no definitive evidence that, for most individuals, CRP adds substantial predictive value above that provided by risk estimation using traditional risk factors for CVD. Use of CRP may add to risk estimation in a limited subset of individuals who are at intermediate predicted risk according to the Framingham risk score. The authors propose that many questions still must be addressed before CRP is incorporated into risk prediction algorithms and before universal screening with CRP can be recommended.