Nearly 1.2 billion people worldwide had mental disorders in 2023, reflecting a 95.5% increase since 1990, a new study has found.
The study, published Thursday in the journal The Lancet, also revealed how trends concerning 12 mental disorders differed by age, sex, location and sociodemographic factors among 204 countries and territories — suggesting “that we are entering an even more concerning phase of worsening mental disorder burden globally,” the authors wrote in the study.
Dr. Damian Santomauro, first and lead study author, “was honestly shocked at the magnitude,” he said via email.
There are many factors at play here, and it is difficult to tease them all apart,” added Santomauro, associate professor in the School of Public Health at the University of Queensland in Australia. “Addressing these risk factors requires global collective leadership.”
The other mental disorders measured were bipolar disorder, schizophrenia, autism spectrum disorder, attention deficit hyperactivity disorder, anorexia, bulimia, dysthymia, conduct disorder and developmental intellectual disability from unknown causes. Dysthymia is a long-term but mild form of depression also known as persistent depressive disorder. Conduct disorder affects children and teens and involves a consistent pattern of disobedient and aggressive behaviors.
The researchers found increases in all 12 disorders, including an 158% rise in anxiety and an 131% uptick in depression compared with 1990. The least common disorders were anorexia, bulimia and schizophrenia — though those conditions aren’t rare, with roughly 4 million, 14 million and 26 million cases, respectively, in 2023. Most mental disorders were more common in females, but autism, conduct disorders, ADHD, personality disorders and inexplicable intellectual disability were actually more common in males.
The study also helps further illuminate how the Covid-19 pandemic may have influenced the rates of certain mental health conditions. Before the Covid-19 pandemic, rates of anxiety, depression and some other disorders were already increasing. But during and since the crisis, depression increased and hasn’t returned to pre-pandemic rates. Anxiety peaked and remained high through 2023, the research team found.
In the research, “issues like underreporting — a common problem with mental illness — are dealt with, but we really don’t know how accurate this is,” said Paul Bolton, senior scientist in the department of mental health at the Johns Hopkins Bloomberg School of Public Health in Baltimore, via email.