Background: Hepatitis B virus (HBV) and hepatitis C virus (HCV) infections may lead to nephropathy. However, the association between different types of viral hepatitis and chronic kidney disease (CKD) is not well established.
Study design: Cross-sectional study.
Setting & participants: A large-scale community study with 54,966 adults in a Taiwanese county endemic for HBV and HCV infection.
Predictor: HCV infection alone, HBV infection alone, HBV/HCV coinfection, and neither.
Outcomes: Proteinuria (urine protein, >or=1+), low (<60 mL/min/1.73 m(2)) estimated glomerular filtration rate (eGFR), and CKD (proteinuria or eGFR <60 mL/min/1.73 m(2)).
Measurements: HBV and HCV infection were defined as a seropositive test result for hepatitis B surface antigen and HCV antibody. Proteinuria was assessed using a repeated dipstick method. eGFR was computed using the 4-variable Modification of Diet in Renal Disease (MDRD) Study equation.
Results: Mean age of the study group was 60.8 years. Prevalences of HCV infection alone, HBV infection alone, HBV/HCV coinfection, and neither were 9.4%, 9.9%, 0.9%, and 79.8%, respectively. 2,994 (5.4%), 7,936 (14.5%), and 9,602 (17.5%) participants had proteinuria, low eGFR, and CKD, respectively. Multivariate logistic regression analyses showed that HCV infection alone (OR, 1.26; 95% CI, 1.17-1.38), but not HBV infection alone (OR, 1.04; 95% CI, 0.96-1.14) or HBV/HCV coinfection (OR, 1.12; 95% CI, 0.87-1.45), was an independent risk factor for CKD. The prevalence of HCV seropositivity was higher in later CKD stages, changing from 8.5% in CKD stage 1 to 14.5% in CKD stages 4-5. Adjusted ORs for HCV infection alone were 1.14 (95% CI, 1.003-1.300) for proteinuria and 1.30 (95% CI, 1.20-1.42) for low eGFR.
Limitations: The definition of CKD status requires a 3-month duration of low eGFR or kidney damage; this was presumed, not documented, in this study.
Conclusions: HCV infection, but not HBV infection, was associated significantly with prevalence and disease severity of CKD in this HBV and HCV endemic area.