Global Trends and Regional Patterns in the Epidemiology of Substance Use Disorders in 1990–2023: A Secondary Analysis of the Global Burden of Disease 2023 Study

Background: Substance use disorders (SUDs) remain a major contributor to global morbidity and mortality, imposing substantial health, social, and economic burdens worldwide. Comprehensive assessments of long-term epidemiological trends across World Health Organization (WHO) regions remain limited. This study examined global and regional trends in the age-standardized prevalence, incidence, and mortality rates of substance use disorders between 1990 and 2023. Methods: This longitudinal ecological study utilized publicly available estimates from the Global Burden of Disease (GBD) 2023 Study. Annual age-standardized prevalence, incidence, and mortality rates of substance use disorders were extracted for the period of 1990–2023. Analyses were conducted for global estimates and the six WHO regions. Absolute and percentage changes between 1990 and 2023 were calculated, while temporal trends were illustrated using annual line graphs. Sensitivity analyses using five representative time points (1990, 2000, 2010, 2020, and 2023) were undertaken to assess the robustness of the observed trends. Results: Globally, the age-standardized prevalence rate declined from 2409.09 (95% UI: 2135.36–2704.19) per 100,000 population in 1990 to 2030.71 (95% UI: 1827.11–2260.99) in 2023, representing a 15.71% reduction. Similarly, the global age-standardized incidence rate decreased from 1052.27 (95% UI: 904.84–1212.43) to 874.07 (95% UI: 759.06–996.86) per 100,000 population, corresponding to a 16.94% decline. In contrast, the global age-standardized mortality rate increased slightly from 3.83 (95% UI: 3.44–4.24) to 3.94 (95% UI: 3.62–4.29) per 100,000 population, representing a 2.87% increase. The Region of the Americas was the only WHO region to demonstrate an increase in prevalence, rising from 3669.36 (95% UI: 3227.49–4165.00) to 3937.92 (95% UI: 3557.22–4366.84) per 100,000 population (7.32%). Mortality in this region increased from 4.46 (95% UI: 4.17–4.78) to 12.84 (95% UI: 11.28–14.62) per 100,000 population, representing a 187.79% increase, whereas incidence declined across all WHO regions. Sensitivity analyses produced findings consistent with those obtained from the complete annual dataset. Conclusions: Substantial regional disparities persist in the epidemiology of SUDs across the WHO regions. The marked increase in prevalence and mortality observed in the Region of the Americas contrasts with improvements in most other WHO regions, pointing to the need for region-specific prevention and treatment, as well as harm-reduction and rehabilitation strategies.