Does increased body mass index with hepatic steatosis contribute to seroclearance of hepatitis B virus (HBV) surface antigen in chronic HBV infection?

Background: Overweight and hepatic steatosis have been increasingly recognized recently. This study aimed to test whether substantial amount of fatty infiltration in liver, which may interfere with cytoplasmic distribution of hepatitis B surface antigen (HBsAg), can contribute to HBsAg seroclearance in HBsAg carriers. Methods: Clinical and laboratory data including ultrasound grading of hepatic steatosis were studied in 54 HBsAg carriers with HBsAg seroclearance, and the results were compared with 108 age- and sex-matched carriers with HBsAg persistence. Results: Body mass index and ultrasound grading of hepatic steatosis were significantly higher in HBsAg carriers with HBsAg seroclearance than in those with HBsAg persistence. The degrees of hepatic steatosis correlated significantly with body mass index (P<0.001). The prevalence of mild hepatic steatosis showed no significant difference (33% (18/54) vs 31% (33/108), P=0.72), but moderate-severe hepatic steatosis was significantly more prevalent in patients with HBsAg seroclearance (33% (18/54) vs 13% (17/108), P=0.01). HBsAg carriers with moderate and severe hepatic steatosis were associated with a 3.2-fold (95% confidence interval: 1.2-8.4, P=0.02) and 3.9-fold (95% confidence interval: 1.1-14.2, P=0.04), respectively, increased odds of HBsAg seroclearance compared to those without hepatic steatosis. Conclusion: Moderate-severe hepatic steatosis may contribute to HBsAg seroclearance in HBsAg carriers.