Anxiety and depression have driven a sharp rise in the number of people suffering from mental disorders. By 2023, such conditions were recorded in nearly 1.2 billion people – double the figure for 1990. Mental disorders have overtaken cardiovascular disease and cancer as the leading cause of disability, according to a new study published in The Lancet.
The Lancet study found that the number of people with mental health problems rose by 96% over the past 30 years, reaching 1.2 billion diagnosed cases by 2023. By comparison, cardiovascular disease cases increased from 311 million in 1990 to 626 million in 2023.
Researchers from the University of Queensland and the Queensland Centre for Mental Health Research in Australia, together with the University of Washington in the United States, analysed data on people with 12 mental disorders across 204 countries. Conditions studied included schizophrenia, anxiety disorder, major depressive disorder, bipolar disorder, autism spectrum disorder, attention deficit hyperactivity disorder, eating disorders and others. Increases were seen across all conditions, with the largest rises for anxiety (up 158%) and depression (up 131%).
Mental disorders are diagnosed more frequently in women than in men – about 620 million cases versus 552 million, the study found. The researchers attribute this to lower self‑esteem among women, a greater tendency to negatively evaluate their bodies, and higher rates of domestic and sexual violence. Other contributing factors include biological changes, particularly during pregnancy and the postpartum period, increased career responsibilities and gender discrimination.
Persistent depressive disorder, bipolar disorder, anorexia nervosa and bulimia nervosa are most common among women. Among men, ADHD, conduct disorder and autism are more prevalent – though this may be linked to diagnostic challenges.
The study notes that women under 39 are the most affected by mental disorders. At the same time, the number of cases among adolescents aged 15‑19 is rising.
Even before the COVID‑19 pandemic, there was a noticeable increase in anxiety, depression and some other disorders, the researchers say. The trend intensified during and after the pandemic. Anxiety peaked and remained high throughout 2023.
The report identified several key risk factors linked to mental illness, including childhood sexual abuse, intimate partner violence and bullying. These are associated with schizophrenia, depression, bipolar disorder, anxiety disorders, conduct disorder and bulimia nervosa.
However, the researchers said these factors alone do not explain the rising number of cases. Exposure rates remained relatively stable and account for only 18% of years of life lost to illness or disability. Mental health is shaped by more complex influences, they stressed, including genetics, biology, poverty, growing inequality and major global crises such as war, pandemics, natural disasters and climate change.
The report describes mental disorders as highly prevalent conditions that cause severe human suffering and long‑term health loss. Beyond personal consequences, mental illness also affects families, workplaces and governments through reduced productivity, lower workforce participation and growing pressure on social welfare and healthcare systems, the authors said.
Although mental disorders have long been a leading cause of disability worldwide, the report warns that the global burden continues to worsen. At the same time, the expansion of mental health services is failing to keep pace with rising demand, the researchers stressed.