Global, Regional, and National Burdens of Depressive Disorders in Adolescents and Young Adults Aged 10–24 Years From 1990 to 2021: A Systematic Analysis Based on the Global Burden of Disease Study 2021

Background: Depressive disorders, including major depressive disorder and dysthymia, are a growing public health concern among adolescents and young adults worldwide. Despite increasing prevalence, long‐term data on their burdens remain limited. This study utilizes the Global Burden of Diseases (GBD), Injuries, and Risk Factors Study database to analyze the trends in depressive disorder burden among this demographic from 1990 to 2021, provide projections of the future burden over the next 20 years, apply age–period–cohort (APC) analysis, and explore associated risk factors. Methods: We utilized data from the GBD 2021, reporting incidence and disability‐adjusted life years (DALYs) per 100,000 population, average annual percentage change (AAPC), and risk factors at global and regional levels. Trends were analyzed by age, sex, and social development index. Joinpoint regression identified significant changes in global trends. NORDPRED and Bayesian age–period–cohort model (BAPC) were employed to project the future burden. The influences of age, period, and cohort on the incidence of mental disorders were evaluated with an APC model. Results: From 1990 to 2021, the global burden of depressive disorders among adolescents and young adults shifted significantly. The AAPC indicated notable incidence increases in specific populations, particularly during the 2010–2021 period (AAPC = 1.79, 95% CI 0.57–3.03), males (AAPC = 0.25, 95% CI −2.6–3.19), the 10–14 age group (AAPC = 0.6, 95% CI −2.2–3.19), populations from high sociodemographic index (SDI) regions (AAPC = 0.63, 95% CI −2.67–4.04), and in the Region of the Americas (AAPC = 0.44, 95% CI −2.92–3.92). Significant increase trends in depressive disorders were observed in joinpoint 2019 for prevalence, incidence, and DALYs. The APC analysis demonstrates that the relative risk (RR) of depressive disorders increases significantly with variations in age, period, and birth cohort, particularly among the 20–24 age group (RR = 1.04, 95% CI 1.02–1.06), during the 2017–2021 period (RR = 1.11, 95% CI 1.09–1.14), and for individuals born between 2002 and 2011 (RR = 1.17, 95% CI 1.12–1.23). Males generally show slightly higher RR in certain age groups, time periods, and birth cohorts. From 1990 to 2021, the percentage contribution of risk factors to DALYs has remained relatively stable. The incidence rate and number of depressive disorders is expected to increase significantly over the next 20 years. Conclusions: The global burden of depressive disorders among adolescents and young adults has significantly increased from 1990 to 2021, with notable rises observed in specific populations. The COVID‐19 outbreak in late 2019, alongside the associated social isolation, educational disruptions, and economic stressors, has exacerbated this trend. Inadequate mental health resources and delayed policy responses likely contributed to the sustained increase in depression rates. Given the projected continued rise in incidence over the next 20 years, urgent mental health interventions and targeted policies for at‐risk groups are essential to address this growing public health challenge.