The epidemiology and burden of ten mental disorders in countries of the Association of Southeast Asian Nations (ASEAN), 1990–2021: findings from the Global Burden of Disease Study 2021

Background: The Association of Southeast Asian Nations (ASEAN), a geopolitical and economic network of ten member states, recognises mental disorders as a health priority; however, sparse epidemiological data hinder the development of effective strategies to reduce their prevalence and burden. We aimed to examine the prevalence, morbidity, and disease burden associated with ten mental disorders from 1990 to 2021 in the ASEAN. Methods: As part of the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD 2021), we analysed estimates for depressive disorders, anxiety disorders, bipolar disorders, schizophrenia, autism spectrum disorders, conduct disorder, attention-deficit hyperactivity disorder (ADHD), eating disorders, idiopathic developmental intellectual disability, and other mental disorders in ten ASEAN member states (Brunei, Cambodia, Indonesia, Laos, Malaysia, Myanmar, the Philippines, Singapore, Thailand, and Viet Nam). Case definitions were based on Diagnostic and Statistical Manual of Mental Disorders or ICD criteria. Prevalence estimates by age, sex, year, and location were derived using DisMod-MR 2.1, a Bayesian meta-regression modelling tool. Disease burden was quantified by estimating years lived with disability (YLDs), years of life lost (YLLs), and disability-adjusted life-years (DALYs). Estimates are presented with 95% uncertainty intervals (UIs). Findings: In 2021, 80·4 million (95% UI 73·8–87·2) cases of mental disorders were reported across ASEAN countries, representing a 70·0% (63·5–77·2) increase since 1990. The age-standardised prevalence of mental disorders was 11·9% (10·9–12·9) in 2021, ranging from 10·1% (9·1–11·3) in Viet Nam to 13·2% (11·6–15·3) in Malaysia, with anxiety and depressive disorders being the most common. The age-standardised prevalence of mental disorders increased by 6·5% (3·7–9·8) between 1990 and 2021. Mental disorders accounted for 11·2 million (8·5–14·3) DALYs in 2021, representing an 87·4% (81·1–94·0) increase since 1990. The 10–14 years age group had the highest disease burden attributable to mental disorders, which accounted for 16·3% (12·7–20·5) of total DALYs in this age group. The largest relative increases in the number of cases of mental disorders between 1990 and 2021 were seen in older adults (182·8% [174·9–192·1] among those aged ≥70 years), despite small relative changes in prevalence in these age groups. Interpretation: The increase in mental disorder prevalence and burden found in this study might partly reflect recent improvements in detection. However, mental disorders now rank among the top ten causes of disease burden in all ASEAN countries except Myanmar, underscoring the urgent need for a comprehensive intersectoral approach to address prevention and treatment gaps across entire populations. Funding: Gates Foundation.