Association of reduced renal function with hepatitis B virus infection and elevated alanine aminotransferase.

BACKGROUND AND OBJECTIVES Clinically, hepatitis B virus (HBV) infection is observed to be associated with nephropathy. However, previous population-based studies failed to show an association between HBV infection and CKD. Therefore, this cross-sectional study was designed to further explore this association. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS A representative sample of 6854 Chinese adults aged 30-75 years was tested for levels of serum hepatitis B surface antigen, alanine aminotransferase (ALT), creatinine, urinary albumin/creatinine ratio, and potential CKD risk factors. RESULTS Neither HBV infection nor elevated ALT (ALT+; ≥ sex-specific 90th percentile of ALT levels of noninfected persons) was significantly associated with reduced estimated GFR (eGFR < 60 ml/min per 1.73 m(2)). Compared with noninfected persons, HBV-infected persons with ALT+, but not those with ALT- (P=0.26), were more likely to have reduced eGFR (odds ratio, 4.07; 95% confidence interval, 1.18-14.0; P=0.03). Further analysis with a general linear model revealed a significant difference in eGFR (mean ± SEM) between HBV-infected and noninfected persons (87.8±0.8 versus 90.2±0.4 ml/min per 1.73 m(2); P=0.002). This difference was mainly derived from that between HBV-infected persons with ALT+ and noninfected persons, with an average difference in eGFR of -4.5 (95% confidence interval, -0.9 to -8.1; P=0.01). HBV infection and ALT+, alone or in combination, were not significantly associated with albuminuria or CKD. CONCLUSIONS HBV infection with elevated ALT, rather than HBV infection alone, was associated with reduced renal function.