Background
An estimated 4 million Americans have been exposed to the hepatitis C virus (HCV) in the US population. The risk of incident and progressive chronic kidney disease and of mortality in patients with normal kidney function infected with HCV is unclear.
Methods
In a nationally representative cohort of 100,518 HCV+ and 920,531 HCV- US Veterans with normal baseline estimated glomerular filtration rate(eGFR), we examined the association of HCV infection with: (1)all-cause mortality, (2)incidence of decreased kidney function (defined as eGFR <60 ml/min/1.73m2 and 25% decrease in eGFR), (3)ESRD, and (4)rate of kidney function decline. Associations were examined in naïve and adjusted Cox models (for time-to-event analyses) and logistic regression models (for slopes), with sequential adjustments for important confounders. Propensity-matched cohort analysis was used in sensitivity analyses.
Results
The patients’ age was 54.5±13.1(mean±SD) years, 22% were black and 92% male, and the baseline eGFR was 88±16 ml/min/1.73m2. In multivariate adjusted models HCV infection was associated with 2.2 fold higher mortality (fully adjusted hazard ratio(aHR), 95%CI: 2.17(2.13–2.21)), 15% higher incidence of decreased kidney function(aHR, 95%CI: 1.15(1.12–1.17)), 22% higher risk of steeper slopes of eGFR (adjusted odds ratio, 95%CI: 1.22(1.19–1.26)) and 98% higher hazard of ESRD (aHR, 95%CI: 1.98 (1.81–2.16)). Quantitatively similar results were found in propensity-matched cohort analyses.
Conclusions
HCV infection is associated with higher mortality risk, incidence of decreased kidney function and progressive loss of kidney function. Randomized controlled trials are warranted to determine whether treatment of HCV infection can prevent the development and progression of CKD and improve patient outcomes.