Hepatitis B Surface Antigen Levels Are Related to Spontaneous Hepatitis B Surface Antigen Seroconversion in Inactive Hepatitis B Carriers

BACKGROUND: The cure for hepatitis B is defined as the hepatitis B surface antigen (HBsAg) seroclearance and/or seroconversion. Predictors of spontaneous seroconversion are not well described. The objective of this study is to identify predictors of spontaneous HBsAg seroconversion from community practice. METHODS: We performed a matched analysis of patients who HBsAg seroconverted (cases) and patients who did not HBsAg seroconvert (control) in a 1:5 ratio according to date of clinic visit between 2014 and 2019 in a large community practice situated in Los Angeles area. Baseline laboratory and clinical data were collected. Univariate analysis and 2-sided t tests were performed, chi test for proportions, and logistic regression. RESULTS: We identified 14 cases and 70 controls. The mean (+/-SD) ages of the cases and controls were 53.6 (+/-12.2) and 49.5 (+/-13.1), respectively (P=0.45). Most patients were women, and all patients were of Asian descent. There were statistically significant mean (+/-SD) baseline differences between cases and controls in HBsAg titers (459.8+/-311.0 and 782.0+/-393.3 IU/mL, P=0.01) and alanine aminotransferase (ALT) values (17.6+/-4.4 and 25.1+/-16.7 IU/mL, P<0.01), respectively. Baseline hepatitis B virus DNA and other pertinent laboratory values did not differ between cases and controls. Eleven of 14 cases (79%) and 11 of 70 controls (16%) baseline HBsAg titers were <1000 IU/mL (P<0.01). The results of a logistic regression demonstrated that HBsAg titers and ALT values were predictor variables for HBsAg seroconversion (P=0.01 and <0.01, respectively). CONCLUSIONS: Spontaneous HBsAg seroclearance and seroconversion is an uncommon event in patients with chronic hepatitis B. The most important predictors of seroconversion are HBsAg titers<1000 IU/mL and low baseline ALT values.