Risk factors of low-level viremia in chronic hepatitis B patients receiving Entecavir monotherapy: a retrospective cohort study

Background and aim: Low-level viremia (LLV), a special case of poor response to antiviral therapy, has become a focus of liver disease research; however, most studies have focused on poor response to antiviral therapy, and little attention has been paid to LLV. Therefore, this study aimed to investigate the factors influencing LLV in patients with chronic hepatitis B (CHB) receiving entecavir (ETV) monotherapy.

Methods: Clinical data of CHB patients receiving ETV treatment for at least 1 year at the outpatient department of the Affiliated Hospital of Xuzhou Medical University from November 2018 to June 2020 were collected. Patients were divided into LLV (180 cases) and sustained virological response (SVR) groups (337 cases) according to the hepatitis B virus (HBV) DNA load at the end of the observation period. Demographic features and laboratory markers were also examined. Univariate and multivariate logistic regression analyses were performed to examine factors influencing LLV in patients receiving long-term ETV monotherapy.

Results: Significant differences were noted between the LLV and SVR groups in terms of age, sex, presence or absence of cirrhosis, HBeAg positivity rate, baseline HBV DNA load, and baseline HBsAg level before treatment. Multivariate logistic regression analysis showed that baseline HBeAg status, HBV DNA load, and HBsAg quantification were pretreatment risk factors for LLV in long-term ETV antiviral therapy.

Conclusions: CHB patients with a high HBV DNA load, high HBsAg quantification, and positive HBeAg results tend to have a high risk of LLV despite long-term ETV antiviral treatment and should be dynamically monitored.