Factors Associated With Rates of HBsAg Seroclearance in Adults With Chronic HBV Infection: A Systematic Review and Meta-analysis

Abstract

Background & Aims: Seroclearance of hepatitis B surface antigen (HBsAg) is a marker for clearance of chronic hepatitis B virus (HBV) infection, but reported annual incidence rates of HBsAg seroclearance vary. We performed a systematic review and meta-analysis to provide more precise estimates of HBsAg seroclearance rates among subgroups and populations. Methods: We searched PubMed, Embase, and the Cochrane library for cohort studies that reported HBsAg seroclearance in adults with chronic HBV infection with more than 1 year of follow-up and at least 1 repeat test for HBsAg. Annual and 5-, 10-, and 15-year cumulative incidence rates were pooled using a random effects model. Results: We analyzed 34 published studies (with 42,588 patients, 303,754 person-years of follow-up, and 3194 HBsAg seroclearance events), including additional and updated aggregated data from 19 studies. The pooled annual rate of HBsAg seroclearance was 1.02% (95% CI, 0.79–1.27). Cumulative incidence rates were 4.03% at 5 years (95% CI, 2.49–5.93), 8.16% at 10 years (95% CI, 5.24–11.72), and 17.99% at 15 years (95% CI, 6.18–23.24). There were no significant differences between the sexes. A higher proportion of patients who tested negative for HBeAg at baseline had seroclearance (1.33%; 95% CI, 0.76–2.05) than those who tested positive for HBeAg (0.40%; 95% CI, 0.25–0.59) (P