A few days ago I posted that CRP may actually be useful. Now this article in NEJM. Suggests that it isn't so useful as we thought it was..
Some thoughts:
- I don't know of any evidence-based guidelines that have yet included CRP in suggested screening tests for cardiovascular disease.
- Looking at the
data (see the tables ) ... I'm impressed that there IS an increased relative risk for elavated CRP ... with similar weight as hypertension. So .. while the news may report this study as a reason NOT to order CRP .. they're in fact just saying that elavated CRP is a moderate predictor of cardiac events and not a strong one - as was previously reported:- We found that the decade-to-decade consistency of values for C-reactive protein, the erythrocyte sedimentation rate, and von Willebrand factor is similar to that of values for blood pressure and total serum cholesterol concentration, suggesting that these inflammatory markers are sufficiently stable for potential use in the long-term prediction of coronary heart disease. Our findings ? reinforced by an updated meta-analysis ? indicate, however, that the odds ratio for coronary heart disease in people with elevated C-reactive protein values is lower than that reported recently. Whereas a previous meta-analysis14 of studies published before 2000 (based on 1953 cases of coronary heart disease) reported an odds ratio for coronary heart disease of about 2.0 (95 percent confidence interval, 1.6 to 2.5), our updated meta-analysis, which adds 5115 cases of coronary heart disease from a further 12 studies, yielded an odds ratio of about 1.5 in a comparison of people with base-line values in the top third with those with base-line values in the bottom third for the population. Moreover, in comparison with major established risk factors (such as an increased total serum cholesterol concentration and cigarette smoking), the C-reactive protein concentration was a relatively moderate predictor of the risk of coronary heart disease and added only marginally to the predictive value of established risk factors for coronary heart disease. These findings suggest that recent recommendations regarding the use of measurements of C-reactive protein in the prediction of coronary heart disease may need to be reviewed.