The global disability-adjusted life-years (DALYs) attributed to mental disorders has increased from 3.1% in 1990 to 4.9% in 2019 while the age-standardized DALY rates did not change significantly, according to the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019 Mental Disorders Collaborators. This research was published in The Lancet Psychiatry.
The researchers measured prevalence, DALYS, years lived with disability (YLDs), and years of life lost (YLLs) for 12 mental disorders in 204 countries and territories by analyzing data they found through PsycINFO, Embase, PubMed, and the Global Health Data Exchange databases.
They found mental disorders increased 48.1% between 1990 (654.8 million estimated cases) and 2019 (970.1 million estimated cases). DALY mental disorders increased from 80.8 million in 1990 to 125.3 million in 2019, but per capita age-standardized DALY rates rose only slightly (1566.2 to 1581.2). About 14.6% of global YLDs in 2019 were attributable to mental disorders.
Age-standardized DALY rates for mental disorders were higher among women compared with men (1426.5 per 100,000 vs 1703.3 per 100,000). Females were more likely to have depressive disorders, anxiety disorders, and eating disorders compared with men. Men were more likely to have attention deficit hyperactivity disorder (ADHD) and autism spectrum disorders compared with females.
Globally, depressive disorders and anxiety disorders were the most common mental disorders. Schizophrenia and eating disorders were the least common.
The largest burdens, based on the proportion of DALYs, due to mental disorders were depressive disorders (37.3%), anxiety disorders (22.9%), and schizophrenia (12.2%), across age groups. DALYs increased during childhood and decreased after 35 years.
Australasia, tropical Latin America, and high-income North America possessed the highest age-standardized prevalence by mental disorder and region in 2019. Depressive disorders were prevalent in sub-Saharan Africa (4,540.4 cases per 100,000 people) and North Africa and the Middle East (4,348.9 cases per 100,000), along with Australasia, tropical Latin America, and high-income North America.
High-income regions tended to have the highest age-standardized prevalence of eating disorders, ADHD, conduct disorder, and autism spectrum disorders. Anorexia nervosa accounted for 268.7 and bulimia nervosa accounted for 49.6 of the 318.3 deaths eating disorders among the studies caused worldwide in 2019.
The researchers discovered mental disorders jumped from the 13th leading cause of DALYs in 1990 to the seventh leading cause of DALYs in 2019, but they were the second most common cause of YLDs in both years.
Depressive disorders were the second-highest cause of YLDs in 2019, ranking highest across all age groups except children aged up to 14 years. Conduct disorder was the highest in that age group.
The United States, Australia, New Zealand, Brazil, countries within Western Europe, sub-Saharan Africa, North Africa and the Middle East had the highest DALY rates in 2019, while the lowest rates were in Asia.
Limitations of the study include scarcity of data from many countries, exclusion of neurological disorders and personality disorders, and lack of reflecting the differential mortality gap for individuals with mental disorders.
The ongoing efforts of the GBD collaboration involving systematic data collection and broad dissemination of outputs are to be commended, the authors state.
“However, there is merit in reconsidering a classification of mental illness that underestimates its true burden and risks further relegating these highly stigmatized disorders, already poorly financed and managed globally. We call upon the GBD group to enter into a wider, collaborative scientific debate on these important issues.”
Disclosure: Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.
GBD 2019 Mental Disorders Collaborators. Global, regional, and national burden of 12 mental disorders in 204 countries and territories, 1990–2019: a systematic analysis for the Global Burden of Disease Study 2019. Lancet Psychiatry. Published online January 10, 2022. doi:10.1016/S2215-0366(21)00395-3