Circulating levels of molecular adhesion correlate with stage of renal disease and C-reactive protein in chronic kidney disease

BACKGROUND: Patients with chronic renal failure (CRF) suffer from a series of complications linked to the atherosclerotic process in which the endothelial dysfunction mediated by the activation of some adhesion molecules plays an important role. This study aims to evaluate circulating levels of intercellular adhesion molecules-1 (ICAM-1) and vascular cell adhesion molecules-1 (VCAM-1) in patients with predialysis CRF, on maintenance hemodialysis (HD) and after kidney transplantation (KTx) and to correlate them with some inflammation and nutritional indexes. METHODS: Thirty two patients with predialysis CRF, 30 on maintenance HD, 36 after KTx and 28 subjects as a control group (C) were included in this study. Circulating levels of ICAM-1 and VCAM-1 were assayed using a specific sandwich ELISA kit. As inflammation indexes, TNFalpha and C-reactive protein (CRP) and, as nutritional indexes, body mass index (BMI), serum albumin, cholesterol, triglycerides, and fibrinogen (F) were evaluated. RESULTS: Serum levels of ICAM-1 and VCAM-1 were progressively higher from C to KTx patients, to those with CRF and those on HD (ANOVA for both; p <0.001). TNFalpha values were lower in HD subjects than in CRF patients, even if in both groups TNFalpha levels were greater than in Tx and control subjects. F and CRP were higher in CRF and HD vs. Tx and control subjects (ANOVA for both p <0.001). No significant correlations were observed between soluble adhesion molecules, albumin and cholesterol, whereas significant correlations were found between CRP and ICAM-1 (r = 0.41; p <0.01), CRP and VCAM-1 (r = 0.39; p <0.01) and between CRP and TNFalpha (r = 0.42; p <0.01). These correlations remained statistically significant even after adjustment for age and blood pressure (all p <0.01). BMI did not differ in the three patient groups. CONCLUSIONS: Circulating levels of adhesion molecules in our study correlated positively with the stage of disease and with one of the inflammatory indexes (CRP), but not with nutritional indexes such as BMI, cholesterol and albumin. The clinical significance of our findings warrants further investigation.