A risk scoring system to predict clinical events in chronic hepatitis B virus infection: A nationwide cohort study

Many patients with chronic hepatitis B do not receive adequate follow‐up. This study aimed to develop a risk score to predict clinical events in patients with chronic hepatitis B virus (HBV) infection at the population level for identifying patients at high risk to warrant regular follow‐up. This study analysed population‐based data from the nationwide claims database of South Korea obtained between 2005 and 2015. We identified 507,239 non‐cirrhotic patients with chronic HBV infection who are not under antiviral treatment. A risk score for predicting clinical events (hepatocellular carcinoma, death or liver transplantation) was developed based on multivariable Cox proportional hazard model in a development cohort (n = 401,745) and validated in a validation cohort (n = 105,494). The cumulative incidence rates of clinical events at 5 years were 2.56% and 2.44% in the development and validation cohorts, respectively. Clinical events in asymptomatic patients with chronic HBV infection (CAP‐B) score ranging from 0 to 7.5 points based on age, sex, socioeconomic status, chronic hepatitis C co‐infection, diabetes mellitus, statin or antiplatelet exposure, smoking, alcohol consumption, alanine aminotransferase and gamma‐glutamyltransferase had good discriminatory accuracy in both the development and validation cohorts (c‐indices for 3‐, 5‐ and 10‐year risk prediction: all 0.786). The predicted and observed probabilities of clinical events were calibrated in both cohorts. A score of >3.5 points identified subjects at distinctly high risk. The CAP‐B score using easily accessible variables can predict clinical events and may allow selection of patients with chronic HBV infection for priority of regular follow‐up.