The Global Burden of Hepatitis B From 1990 to 2021: Trends, Socioeconomic Inequalities, and Predictions to 2035

Background Hepatitis B remains a global threat with significant disparities. This study provides a comprehensive assessment of its long‐term burden, inequalities, and future trajectories to inform elimination strategies. Methods Using data from the Global Burden of Disease Study 2021, we analyzed age‐standardized rates (ASRs) of incidence, prevalence, mortality, and disability‐adjusted life years (DALYs) from 1990 to 2021. We quantified socioeconomic inequalities using the slope index of inequality (SII) and concentration index, and projected future trends to 2035 using Bayesian age–period–cohort modeling. Results From 1990 to 2021, all ASRs declined annually (1.64%–1.81%). However, an estimated 68.5 million new infections and 291 million prevalent cases persisted in 2021. The burden was heavily concentrated in low‐SDI regions (e.g., sub‐Saharan Africa) and among males. Inequality analysis revealed narrowing absolute gaps but widening relative inequity. Projections indicate a continued decline in ASRs but a rise in absolute deaths by 2035, driven by an aging cohort with prevalent infections. Conclusions Deep‐seated socioeconomic inequality is the main barrier to elimination. Future efforts must accelerate prevention in high‐burden settings while globally scaling up treatment and surveillance to address the legacy of past infections.