Age-period-cohort model of hepatitis B serum markers in Chaoyang district, Beijing

  Objective  To investigate the prevalence of hepatitis B serum markers in different age groups, periods and birth cohorts in Chaoyang district of Beijing.

  Methods  In 2010, 2015 and 2020, residents aged 1–75 years, who had been lived in Chaoyang District more than 6 months, were selected with multistage cluster random sampling to conduct questionnaire surveys, and blood samples (3–5 mL) were collected from them for the detections of hepatitis B virus surface antigen (HBsAg), hepatitis B virus surface antibody (HBsAb) and hepatitis B virus core antibody (HBcAb) respectively. The age-period-cohort model and intrinsic estimator algorithm were used to estimate the effects of age, period and cohort on HBsAg positive rate, HBsAb positive rate and hepatitis B infection rate respectively.

  Results  The HBsAg positive rate in residents in Chaoyang in 2010, 2015 and 2020 showed no significant differences with the standardized rates of 2.61%, 2.50% and 2.52%, respectively (P=0.830, χ²=0.374). The age-period-cohort effect on hepatitis B virus infection was significant. The hepatitis B infection rate firstly increased and then decreased with age, with the highest rate in the 40～ years old group. The exposure risk of cohort decreased with birth years.

  Conclusion  HBsAg positive rate was at a moderate level in Chaoyang. Hepatitis B exposure risk firstly increased and then decreased with age and decreased with cohort.