Inflammation markers, adhesion molecules, and all-cause and cardiovascular mortality in patients with ESRD: searching for the best risk marker by multivariate modeling.

Inflammation is a major risk factor for mortality and cardiovascular (CV) complications in patients with ESRD. The predictive value of C-reactive protein (CRP) of the main proinflammatory cytokines (IL-1beta, IL-6, IL-18, and TNF-alpha) and of two adhesion molecules (intercellular adhesion molecule-1 and vascular cell adhesion molecule-1) in 217 dialysis patients was compared. Serum IL-6 and CRP added significant prediction power to the multivariate Cox model of all-cause death, and the gain in the prediction power attributable to IL-6 was approximately two times higher than that of CRP. Patients in the third tertiles of serum IL-6 and CRP had a relative risk of all-cause mortality 2.5 and 1.8 times higher than those in the first corresponding tertiles, and there was no statistical difference between these two relative risks. The gain in prediction power associated with TNF-alpha, IL-beta, IL-18, intercellular adhesion molecule-1, and vascular cell adhesion molecule-1 was of small degree (P = NS). Similarly, serum IL-6 added the highest prediction power to the CV death model, and the IL-6 attributable gain was approximately two times higher than that of serum CRP. However, the risk estimate for CV mortality of patients with high serum IL-6 did not differ significantly from that of patients with high serum CRP. IL-6 adds significantly greater predictive power for all-cause and CV death to statistical models based on traditional and nontraditional risk factors in ESRD patients. However, the risk estimate by CRP being reasonably close to that of IL-6, CRP may be a cheap alternative to IL-6 in clinical practice.