Division of Nephrology and Dialysis, Maggiore Hospital, IRCCS Foundation, Milano, Italy Division of Hepatology, School of Medicine, University of Miami, Miami, FL, USA.
Summary. Recent evidence has been accumulated showing that anti-HCV-positive serologic status is significantly associated with lower survival in dialysis populations, but the mechanisms underlying this negative relationship are still unclear. The aim of this study was to conduct a systematic review of the published medical literature concerning the impact of hepatitis C virus (HCV) infection on all-cause and disease-specific mortality of patients on regular dialysis. The relative risk of all-cause, cardiovascular and liver disease-related mortality was regarded as the most reliable outcome end-point. Study-specific relative risks were weighted by the inverse of their variance to obtain fixed- and random effect pooled estimates for mortality with HCV across the published studies. We identified fourteen observational studies involving 145 608 unique patients on long-term dialysis. Pooling of study results demonstrated that anti-HCV antibody was an independent and significant risk factor for death in patients on maintenance dialysis. The summary estimate for adjusted relative risk (all-cause mortality) was 1.35 with a 95% confidence interval (CI) of 1.25-1.47. Stratified analysis showed that the adjusted RR for liver disease-related death was 3.82 (95% CI, 1.92; 7.61); heterogeneity statistics, R(i) = 0.58 (P-value by Q-test = 0.087). The adjusted RR for cardiovascular mortality was 1.26 (95% CI, 1.10; 1.45); no heterogeneity was found (NS). This meta-analysis of observational studies indicates that anti-HCV-positive patients on dialysis have an increased risk of either liver or cardiovascular disease-related mortality compared with anti-HCV-negative patients. Further studies are in progress to understand better the link between HCV and cardiovascular risk among patients on maintenance dialysis.