Global, Regional, and National Burden of Major Depressive Disorder From 1990 to 2021: Analysis of Data From GBD 2021

Background Major depressive disorder (MDD) is a leading cause of disability worldwide. This study aimed to quantify the global, regional, and national burden of MDD from 1990 to 2021 and project future trends through 2040. Methods This ecological trend analysis utilized data from global burden of disease (GBD) 2021 to assess MDD burden across 204 countries and territories. Temporal trends were evaluated using the estimated annual percentage change (EAPC) and Bayesian Age-Period-Cohort (BAPC) models. Results In 2021, the global ASPR of MDD was 2413.8 (95% UI: 1957.5-2977.4) per 100 000 population, the ASIR was 3610.4 (95% UI: 2936.9-4461.8) per 100 000 population, and the ASDR was 557.9 (95% UI: 381.2-760.7) per 100 000 population. Low-socio-demographic index (SDI) regions exhibited the highest age-standardized prevalence rate (ASPR), age-standardized incidence rate (ASIR), and age standardized disability adjusted life year rate (ASDR), while Middle-SDI regions showed the lowest disability adjusted life year rate. Individuals aged 20-50 years bore a disproportionately high burden. Females consistently showed higher ASPR than males across all SDI quintiles. BAPC projections indicated that ASPR, ASIR, and ASDR will continue to rise from 2021 to 2040, with females maintaining higher rates than males. Conclusions MDD remains an increasing global burden with marked disparities. Targeted interventions are urgently needed in low-SDI regions and among females and young adults.