Global burden of depression and anxiety disorders in older adults, 1990-2019: An analysis of age-period-cohort and temporal-spatial patterns

BACKGROUND: Mental disorders are the leading causes of the global health-related burden and account for 10.6% of total disability (in disability adjusted life years, DALYs) among older adults, with depression and anxiety disorders being the most common contributors to this burden. This study provided a comprehensive epidemiological update on their global burden in older populations, analyzing evolving temporal trends, spatial distribution shifts, and identifying high-risk subgroups and geographic regions. METHOD: Prevalence rates and disability-adjusted life years (DALYs) for depression and anxiety disorders in older adults from 1990 to 2019 were estimated using the GBD 2019. The Age-period-cohort (APC) modeling was applied to investigate the reasons behind these trends. In addition, we assessed the spatial patterns in different regions using the global and local Moran Index. RESULTS: In 2019, 57.78 million (95 % UI 50.04, 66.30) older adults experienced depression and 46.26 million (95 % UI 59.93, 36.57) suffered from anxiety disorders globally. Depression accounted for 9.21 million DALYs (rate: 908.94, 95 % UI 625.45, 1234.56), while anxiety disorders contributed to 4.08 million DALYs (rate: 402.95, 95 % UI 264.96, 581.75). From 1990 to 2019, the depression prevalence increased (EAPC = 0.0424, 95 % CI 0.0261, 0.0587), and DALYs rates rose slightly (EAPC = 0.0142, 95 % CI -0.0071, 0.035). In contrast, the anxiety disorders prevalence and DALYs rate declined over the same period [EAPC = -0.1476 (95 % CI -0.1924,-0.1027) and -0.1476 (95 % CI -0.1917,-0.1035)]. Age-specific trends revealed inverted U-shaped depression trajectories, peaking among individuals aged 70-74 years, whereas anxiety disorders exhibited a U-shaped decline with the steepest reductions occurring at the extremes and slower declines in middle age groups. Males exhibited faster-growing depression burdens and rising late-life rates of anxiety disorders, contrasting with the declining trend observed in females. Socio-demographic disparities highlighted low-SDI regions with the highest depression burden (e.g., sub-Saharan Africa) versus high-SDI clusters for anxiety disorders (e.g., Western Europe). Spatial analyses identified depression hotspots in sub-Saharan Africa and anxiety clusters in Latin America and Western Europe, emphasizing divergent geographic patterns. CONCLUSION: Combining temporal and spatial patterns, we explored temporal trends and five spatial patterns in global depression and anxiety disorders. The prevalence of depression and anxiety disorders was significantly elevated in regions exhibiting both fluctuating and stable high-aggregation patterns, particularly in Eastern/Western sub-Saharan Africa and Southern Latin America. National governments prioritize implementing targeted interventions to alleviate these burdens, while future studies should validate findings through comprehensive datasets and individual-level data to refine prevention strategies for high-risk populations and regions.