The Global Burden of Schizophrenia: Findings from the 2021 Global Burden of Diseases, Injuries, and Risk Factors Study

Abstract Background and Hypothesis We utilized data from the 2021 Global Burden of Disease (GBD) Study to (i) provide estimates of the incidence, prevalence, and illness-related burden associated with schizophrenia; (ii) examine how these rates have changed from 1990-2021; and (iii) explore the association of these rates with several country-level variables (e.g., access/quality of healthcare systems). Study Design The GBD study provides estimates for the incidence, prevalence, and disability-adjusted life years (DALYs) associated with 371 illness, injuries, and risk factors by age and sex across 204 countries and territories. We examined data from the GBD 2021 study to describe the global epidemiology of schizophrenia as well as the association between metrics of schizophrenia epidemiology and country-level variables previously associated with these metrics. Study Results In 2021, the global age-standardized incidence, prevalence, and DALY rates were 15.4, 277.7, and 177.8 per 100,000 individuals, respectively. Between 1990-2021, global incidence rates (both age-standardized and crude) declined, whereas crude prevalence and DALY rates per 100,000 increased and age-standardized prevalence and DALYs remained unchanged. However, these findings varied by age, gender, and geography. Changes in country-level variables between 1990-2021 (e.g., alcohol use and per capita income) were associated with changes in incidence, prevalence, and DALY rates over this same time period. Conclusions Schizophrenia remains a significant health concern worldwide. Our results highlight the need for health systems to prepare to address the growing prevalence of schizophrenia which may be greatest among older adults, and especially older women.