In Reply

Abstract

Plasma levels of C-reactive protein (CRP) seem to be a useful predictor of cardiovascular events and outcome in the general population.1Ridker P.M. Clinical application of C-reactive protein for cardiovascular disease detection and prevention.Circulation. 2003; 107: 363-369Crossref PubMed Scopus (1980) Google Scholar Their utility in the dialysis population is less well defined. Overt infection is a cause of CRP levels greater than 10 mg/L; however, other causes, such as biofilms or subclinical infection of the vascular or peritoneal access, congestive heart failure, ischemic heart disease, failed kidney transplant, and active rheumatological diseases, also should be considered. There is likely to be significant overlap in plasma CRP levels between noninfectious and infectious causes, especially when the latter is early in its course. Although elevated CRP levels, independent of causes, predict all-cause and cardiovascular mortality in patients with end-stage renal disease,2National Kidney FoundationK/DOQI Clinical Practice Guidelines for Cardiovascular Disease in Dialysis Patients.Am J Kidney Dis. 2005; 45: S76-S89Google Scholar treatment of elevated CRP levels probably varies depending on the cause. Even in the absence of obvious infection, the efficacy of statin therapy to decrease plasma CRP levels and cardiovascular events in the dialysis population has not been established. Therefore, a definitive cutoff level for action cannot yet be recommended for this patient population.Persistent elevation3Nascimento M.M. Pecoits-Filho R. Qureshi A.R. et al.The prognostic influence of fluctuating levels of C-reactive protein in Brazilian hemodialysis patients A prospective study.Nephrol Dial Transplant. 2004; 19: 2803-2809Crossref PubMed Scopus (63) Google Scholar or an increase in CRP levels after a hemodialysis session4Korevaar J.C. van Manen J.G. Dekker F.D. de Waart D.R. Boeschoten E.W. Krediet R.T. Effect of an increase in CRP level during a hemodialysis session on mortality.J Am Soc Nephrol. 2004; 15 (2916–1922)Crossref Scopus (84) Google Scholar have been associated with greater mortality. Plasma interleukin 6 levels may be a superior predictor of outcome compared with CRP levels in patients with end-stage renal disease.5Stenvinkel P. Lindholm B. C-Reactive protein in end-stage renal disease Are there reasons to measure it?.Blood Purif. 2005; 23: 72-78Crossref PubMed Scopus (54) Google Scholar Additional studies are required to determine which biomarker of inflammation and the timing of measurements are most useful for the management of patients with cardiovascular diseases. It also is important to evaluate the role of anti-inflammatory strategies and their specific targets on cardiovascular outcome in this patient population. Plasma levels of C-reactive protein (CRP) seem to be a useful predictor of cardiovascular events and outcome in the general population.1Ridker P.M. Clinical application of C-reactive protein for cardiovascular disease detection and prevention.Circulation. 2003; 107: 363-369Crossref PubMed Scopus (1980) Google Scholar Their utility in the dialysis population is less well defined. Overt infection is a cause of CRP levels greater than 10 mg/L; however, other causes, such as biofilms or subclinical infection of the vascular or peritoneal access, congestive heart failure, ischemic heart disease, failed kidney transplant, and active rheumatological diseases, also should be considered. There is likely to be significant overlap in plasma CRP levels between noninfectious and infectious causes, especially when the latter is early in its course. Although elevated CRP levels, independent of causes, predict all-cause and cardiovascular mortality in patients with end-stage renal disease,2National Kidney FoundationK/DOQI Clinical Practice Guidelines for Cardiovascular Disease in Dialysis Patients.Am J Kidney Dis. 2005; 45: S76-S89Google Scholar treatment of elevated CRP levels probably varies depending on the cause. Even in the absence of obvious infection, the efficacy of statin therapy to decrease plasma CRP levels and cardiovascular events in the dialysis population has not been established. Therefore, a definitive cutoff level for action cannot yet be recommended for this patient population. Persistent elevation3Nascimento M.M. Pecoits-Filho R. Qureshi A.R. et al.The prognostic influence of fluctuating levels of C-reactive protein in Brazilian hemodialysis patients A prospective study.Nephrol Dial Transplant. 2004; 19: 2803-2809Crossref PubMed Scopus (63) Google Scholar or an increase in CRP levels after a hemodialysis session4Korevaar J.C. van Manen J.G. Dekker F.D. de Waart D.R. Boeschoten E.W. Krediet R.T. Effect of an increase in CRP level during a hemodialysis session on mortality.J Am Soc Nephrol. 2004; 15 (2916–1922)Crossref Scopus (84) Google Scholar have been associated with greater mortality. Plasma interleukin 6 levels may be a superior predictor of outcome compared with CRP levels in patients with end-stage renal disease.5Stenvinkel P. Lindholm B. C-Reactive protein in end-stage renal disease Are there reasons to measure it?.Blood Purif. 2005; 23: 72-78Crossref PubMed Scopus (54) Google Scholar Additional studies are required to determine which biomarker of inflammation and the timing of measurements are most useful for the management of patients with cardiovascular diseases. It also is important to evaluate the role of anti-inflammatory strategies and their specific targets on cardiovascular outcome in this patient population.