Hepatitis C and CKD are both highly prevalent diseases in the United States. Data has demonstrated that hepatitis C may be causally linked to some glomerular diseases, and that patients who are positive for hepatitis C have increased risk for albuminuria.
To determine if hepatitis C infection is associated with increased likelihood of CKD, we performed retrospective cross-sectional and longitudinal analyses of a large clinical database.
Setting and Participants
Data on a study population of 13,139 African American and white patients tested for hepatitis C between 1994 and 2004 was extracted from a computerized database from a clinical population of an urban hospital and affiliated clinics.
Hepatitis C by ELISA.
In cross-sectional analysis, CKD was defined as a minimum estimated GFR (eGFR) value < 60 ml/min/1.73 m2, using the 4 variable MDRD Study equation, or proteinuria. In longitudinal analysis, CKD was defined as eGFR < 60 ml/min/1.73 m2.
Potential confounders investigated included sex, age, race, HIV status, chronic hypertension, diabetes, and other laboratory abnormalities.
A total of 3938 patients (30.0 %) were positive for hepatitis C, and 2549 (19.4%) had CKD. Of those with CKD, 1999 (78.4%) had eGFR < 60 ml/min/1.73 m2, 186 (7.3%) had proteinuria, and 364(14.3%) had both. In cross-sectional analysis, after controlling for diabetes, hypertension, age, alanine serotransferase (AST), and HIV status, patients who tested positive for hepatitis C had a decreased risk of CKD (OR=0.69, 95% CI 0.62–0.77). A total of 7,038 subjects without CKD were followed for a median of 3.5 years. Of these, 2243 (31.8%) were hepatitis C positive at onset of follow-up. In longitudinal analysis, after adjustment for age, baseline eGFR, diabetes, hypertension, AST and HIV, the HR (95% CI) for development of CKD compared to those who were hepatitis C negative was 1.024 (0.908 1.156).
Retrospective design, clinical database with missing values, different hepatitis C assays used over the study time period, limited data on proteinuria.
Our results do not support the hypothesis that infection with the hepatitis C virus per se is associated with an increased risk of having or developing CKD.