Background: Overall and cardiovascular mortality are significantly higher in hemodialysis patients with elevated C-reactive protein (CRP). The aim of this study was to determine whether CRP is a marker of overall and cardiovascular morbidity in chronic kidney disease (CKD) 3-5 patients.
Methods: 90 chronic kidney disease 3-5 patients were prospectively followed during a period of 24 months. Cardiovascular events were defined as episodes of myocardial infarction, stroke, angina pectoris and/or peripheral vascular disease. Morbidity was analyzed in terms of both the need for hospital admission (> 48 h) and total number of days of hospitalization during the follow-up period. CRP was stratified into tertiles of low (< 8 mg/l), medium (8-10.5 mg/l) and high (> 10.5 mg/l). The use of some drugs such as ACE inhibitor and ARAII were also recorded.
Results: During the follow-up period, 23 patients (25%) required hospital admission. New cardiovascular events were observed in 20 patients (22%), 10 patients died during the follow-up. Adjusted Cox regression analysis revealed that CRP and serum albumin significantly predicted the risk of cardiovascular events. Similarly, high CRP, low serum albumin and low hemoglobin levels predicted morbidity as measured by the number of hospitalizations. Hemoglobin and albumin levels were lower in patients with high CRP (> or = 10.5 mg/l, highest tertile) as compared with low CRP levels (< or = 8 mg/l, lowest tertile). Patients receiving treatment with angiotensin-converting enzyme (ACE) inhibitors or angiotensin II receptor Type 1 antagonist (ARA-II) had significantly lower levels of CRP than those who were not under such treatment (n = 46, CRP = 8.7 (5.1-29.8) vs n = 44, CRP = 10.4 (6.1-37.2), p < 0.05) (Figure 1).
Conclusions: Our results show that CRP and low albumin, markers of inflammation, predict cardiovascular events and morbidity in CKD 3-5 patients before initiation of chronic hemodialysis.