Objectives
This study evaluated the epidemiological burden and temporal trends of mental disorders in Vietnam from 1990 to 2023 and projected the future burden through 2040. Methods: Global Burden of Disease Study 2023 data were used to analyze the age-standardized prevalence rate (ASPR), age-standardized incidence rate (ASIR), and age-standardized disability-adjusted life-year rate (ASDAR) by age, sex, and diagnostic subtype. Temporal trends were quantified using the estimated annual percentage change (EAPC), and Pearson correlation analysis examined associations with Vietnam’s human development index (HDI). Bayesian structural time series (BSTS) models were used to forecast the burden through 2040. Results: In 2023, approximately 9.1 million individuals in Vietnam had mental disorders, with 2.94 million annual incident cases and 1.41 million disability-adjusted life-years. Depressive disorders ranked highest across all metrics, and females consistently had higher agestandardized rates than males. Age-standardized rates increased significantly from 1990 to 2023: ASIR, 1.10% EAPC (95% confidence interval [CI], 0.87%–1.33%); ASPR, 0.27% EAPC (95% CI, 0.21%–0.33%); and ASDAR, 0.52% EAPC (95% CI, 0.46%–0.58%). Mental disorder burden was strongly positively correlated with HDI (r =0.773–0.909, all p<0.001). BSTS models projected continued increases through 2040 (ASPR, 9,003.75; ASIR, 3,307.11; ASDAR, 1,408.05 per 100,000 population). Conclusion: Mental disorders constitute an escalating public health challenge in Vietnam, with the burden increasing steadily over 3 decades and projected to continue rising through 2040. Reorientation toward an integrated, community-based care model, alongside targeted workforce expansion and systematic integration of mental health services into primary care, is essential to mitigate this growing burden.