The idea of utilizing CRP in the early triage of individuals with potential cardiovascular disease was advanced in 2003 by AHA/ CDC with the publication of the AHA/CDC Scientific Statement on
Markers of Inflammation and Cardiovascular Disease.
The scientific statement (a consensus report derived from a weekend conference (actually a Thursday and Friday) of "experts in the field") attempted to determine in what situations CRP testing could be valuable in prognosticating cardiovascular risk.
The recommendation was that when a patient is found to be at intermediate risk for CAD based on the routine clinical risk factors of obesity, diabetes, smoking, hypertension etc, elevated CRP levels might tip the scales to more aggressive workup and treatment. Obviously in high risk individuals CRP is not useful since they warrant aggressive workup/ therapy anyway. In low risk individuals, the specificity is too low to be beneficial.
The AHA/CDC recommendations specify that two separate "high-specificity CRP" (hs-CRP) levels should be measured and averaged together. Levels less than 1 mg/L are considered "low," levels from 1 to 3 mg/L are considered "average," and levels greater than 3 mg/L are considered "high." People in the "high" group have about a two-fold increase in relative risk for cardiovascular disease compared to those in the low-risk group.
I am unaware of any modification to or refutation of this consensus statement to date.
The average Gyn may be more predisposed to measuring CRP levels given that the Women's Health Study demonstrated that women with elevated CRP levels had increased risk even if their cholesterol levels were normal.
So, if your patient has intermediate risk factors for cardiovascular disease, the elevated CRP might tip your scales to more aggressive preoperative workup. On the other hand, if she is a thin, fit woman with normal blood pressure, you might be concerned that her elevated CRP simply reflects an increased risk of badness and need for adjuvant chemo if she is in your clinic for colorectal Ca.
In the additional 128 stage II patients, CRP-positive patients showed a 3-year survival rate of only 55% without adjuvant chemotherapy, but this increased to 90% with adjuvant chemotherapy
Lots of info on CRP in colorectal cancer and cardiovascular disease and a whole host of other topics is just a click away
Pubmed.
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