Divergent Trajectories in Adolescent Depression: An Age-Period-Cohort Assessment of the China-Global Divide, 1990-2036

Objective : To inform targeted prevention and control strategies, A systematic analysis was conducted to examine the trends and disparities in the burden of depression among teens who aged 10-24y in China compared to globally between 1990 and 2021, with estimates to 2036. Leveraging data from the Global Burden of Disease Study (GBD) 2021. Methods : Drawing on the GBD 2021 result tools, an analysis was conducted to compare the age-standardized incidence, prevalence, and DALY rates of adolescent depression in China relative to global averages. We evaluated temporal trends by estimating the annual percentage change (EAPC) and utilized Bayesian age-period-cohort (BAPC) models to analyze influencing factors and estimate the future burden. Results : Between 1990 and 2021, global adolescent depression cases rose by 49.41%, while China saw a striking 57.49% decrease. The gender gap was wider in China, with females bearing a consistently higher burden. Globally, the sharpest incidence increase occurred in the 10–14 age group, whereas China's most notable decline was in the 20–24 group. Projections indicate a continued decline in China's incidence through 2036, contrasting with persistently high global rates. Conclusion : China has achieved a notable decline in adolescent depression from 1990 to 2021, contrasting with the rising global trend. This success is attributed to policy interventions, socioeconomic development, and expanded health services. Sustaining progress requires further refining mental health systems, prioritizing female and younger adolescents, and integrating AI to enhance early detection and intervention.