A large-scale scientific study has revealed that approximately 1.2 billion people worldwide are living with a mental disorder, a figure nearly double the number recorded in 1990.
This is what has made mental disorders the number one cause of disability worldwide, ahead of heart disease, cancer and musculoskeletal diseases.
The study, led by researchers at the Institute for Health Metrics and Evaluation in collaboration with the University of Queensland and published in The Lancet, is the most comprehensive of its kind to date.
It examined the prevalence and burden of mental disorders among men and women, across 25 age groups, in 21 geographic regions, and 204 countries and territories, during the period from 1990 to 2023.
The study included 12 mental disorders, with anxiety and major depressive disorder being the most impactful, ranking 11th and 15th respectively in terms of burden among 304 diseases and injuries globally.
In 2023, mental disorders accounted for 171 million disability-adjusted life years (DALYs), ranking them as the fifth largest cause of overall disease burden. These disorders also represented more than 17% of all years lived with a disability, reflecting their growing impact.
The recent increases are largely due to anxiety and major depressive disorders. Since 2019, the prevalence of major depression has risen by approximately 24%, while anxiety disorders have increased by more than 47%, with both disorders peaking in the years following the COVID-19 pandemic.
Dr. Damien Santomoro, the study's lead author, says these increases may reflect the effects of pandemic-related stress, as well as long-term factors such as poverty, insecurity, abuse, violence, and reduced social interaction. He emphasizes that addressing this challenge requires sustained investment in mental health systems and expanded access to care.
Mental disorders affect all age groups, but they peak among people aged 15 to 19, a critical period that shapes the future of education, employment, and personal relationships.
In early childhood, conditions such as autism, attention deficit hyperactivity disorder and behavioral disorders are more prevalent, and boys are affected at higher rates than girls.
As children grow into adolescence, anxiety and depression become the main culprits behind the burden of mental disorders.
In terms of gender, women are disproportionately affected. In 2023, 620 million women suffered from a mental health disorder compared to 552 million men. This is attributed to factors such as exposure to domestic violence and sexual assault, increased caregiving responsibilities, and gender discrimination.
Despite the prevalence of mental disorders, treatment remains unavailable to many. It is estimated that only 9% of people with major depression worldwide receive even the minimum appropriate treatment, with less than 5% receiving adequate care in 90 countries. Only in a small number of high-income countries, such as Australia, Canada, and the Netherlands, does treatment coverage exceed 30%.
Researchers emphasize that expanding access to services, particularly in low- and middle-income countries, will be crucial, requiring sustained investment and coordinated global action to improve mental health conditions worldwide.
