#1625 Influence of polymorphisms in genes for interleukin-6 and interleukin-10 on dialysis patients survival

Abstract

Abstract Background and Aims Chronic inflammation is an important non-traditional risk factor for morbidity and mortality in patients with terminal kidney disease. Associated occurrence of malnutrition, inflammation and atherosclerosis was observed in patients on dialyses and marked as MIA syndrome, a vicious circle in which pro inflammatory cytokines play a key role. It is known that there were individual differences in creation of cytokines, and it is assumed that polymorphisms in the promoter regions of cytokine genes can have a key role in the predisposition to chronic inflammation and its consequences. We investigated association between interleukin-6 -174 G>C, interleukin-10 -1082 G>A, inteleukin-10 -819 T>C genotypes with the survival of patients with terminal renal failure. Method In this study, a total of 128 patients were examined, 77 on the regular hemodialysis (HD) and 51 on the peritoneal dialysis (PD) program of the UKCS Nephrology Clinic in Belgrade. Age, gender, BMI, duration of HD/PD, C-reactive protein (CRP), albumin and IL-6 and IL-10 concentration in serum were analyzed. Analysis of IL6 -174G>C and IL10 -819T>C polymorphisms was performed by the allele-specific PCR method, and analysis of the IL10 -1082G>A polymorphism by the PCR/RFLPs method. The patients were followed for 36 months and during that time 37 patients died. Results Univariate analysis showed that significant predictors of mortality were age (OR= 1.16,95%CI 1.061-1.269, p=0.001), albumin concentration (OR= 0.81, 95%CI 0.656-0.999, p=0.049), CRP (OR= 1.06, 95%CI 1003-1.124, p=0.039) and IL-6 (OR= 1.12, 95%CI 1.038-1.216, p=0.004), as well as IL-6176G>C gene polymorphism (OR= 0.82, 95%CI 0.097-0.805, p=0.018), while in multivariate logistic model separated only the concentration of IL-6 and the polymorphism in the gene for IL-6 -174 G>C. Estimated arithmetic mean of survival in subjects with the IL-6 -174GG genotype was 33.1 months (95%CI 30.8-35.3), GC 34.6 months (95% CI 33.6-35.7) and CC 26.1 (95% CI 20.0-32.2). There is statistically significant difference in survival time in relation to IL-6 -174 G>C genotype (chi-square=11.398; p=0.003). Estimated arithmetic mean survival in patients with the IL-10 -1082 GG genotype was 32.6 months (95% CI 30.5-35.2), in GA 31.5 (95% CI 29.2-33.8) and in AA 36.0 (95% CI 35.9-36.1). Exists statistically significant difference in survival time in relation to 1082G>A genotype (chi-square=9.669; p=0.008). Conclusion Monitoring of survival in 128 patients during 36 months showed that significant worse survival was experienced in patients with IL -6 -174 CC genotype, while polymorphisms in IL 10 gene-1082 G>A and -819T>C did not significantly affect survival. In this group of patients, beside IL-6-174 CC genotype, concentrations of IL-6, C reactive protein and albumin were significant predictors of mortality as well as Kt/V.