C-reactive protein in end-stage renal disease: are there reasons to measure it?

Cardiovascular disease (CVD) remains the major cause of morbidity and mortality in end-stage renal disease (ESRD) patients. As traditional risk factors cannot alone explain the unacceptable high prevalence and incidence of CVD in this population, inflammation (a common phenomenon in ESRD), and other non-traditional risk factors are likely to contribute. Among several inflammatory biomarkers used to assess inflammation, high-sensitivity C-reactive protein (hs-CRP) has attracted the most interest. Indeed, in the general population the consistency of prognostic data for hs-CRP and the practicality of its use have led to suggestions that CRP should be used as a clinical criterion for global cardiovascular risk prediction. As CRP is so strongly associated with vascular disease, it has been suggested that this protein is not only a marker, but also a mediator, of atherogenesis. Indeed, recent in vitro data from studies on endothelial cells, monocytes-macrophages and smooth muscle cells support a direct role for CRP in atherogenesis. In ESRD, hs-CRP has been proven to be a strong predictor of both cardiovascular and all-cause mortality, and associated with oxidative stress, vascular calcification and endothelial dysfunction. As recent studies suggest that interleukin-6 may be a somewhat better outcome predictor than hs-CRP, comparative studies are needed to evaluate which inflammation biomarker is the most cost-effective predictor of outcome in the ESRD patient population.