Nearly 1.2 billion people worldwide had mental disorders in 2023, reflecting a 95.5% increase since 1990, a new study has found, reports BritPanorama.
The largest increases were in anxiety and depression, which were also the most common disorders in 2023. In third place was a residual category of personality disorders not accompanied by other mental or substance use disorders.
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.
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 behaviours.
The researchers found increases in all 12 disorders, including a 158% rise in anxiety and a 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. However, the estimates “are the best we have” and “as close to the real figures in the world as we are likely to get,” added Bolton, who wasn’t involved in the study.
The peak has shifted to younger people
Mental disorders increasingly are a leading cause of disability, with females and people ages 15 to 39 most affected. While greater burden among females is typical, the peak in the 15- to 19-year-old age group is a first in GBD study history, Santomauro said. “We have historically always seen this peak in middle age,” he added.
The younger age range is a vulnerable and important period for the development of the brain and social and intellectual skills, said Dr. Robert Trestman, chair of psychiatry and behavioral medicine at the Virginia Tech Carilion School of Medicine. Interrupted development can have long-term repercussions, added Trestman, who wasn’t involved in the study.
Many positive and negative factors contribute to the higher rates, experts said. “The stigma of mental illness has been substantially reduced — people are much more comfortable coming forward, as opposed to suffering in silence,” Trestman said. Trestman is also chair of the American Psychiatric Association’s council on healthcare systems and financing.
Detection and diagnosis of mental health conditions have improved over time, said Dr. Arthur Evans, CEO of the American Psychological Association, via email. He was not involved in the research. Population growth and longer lifespans also contribute, Santomauro said. At the same time, “if you take a step back and look at the conditions in which people are living, it’s sadly not surprising,” Trestman said of the increases. Many factors are triggering or compounding mental health conditions, experts said, including genetics, economic instability, trauma, inadequate or unaffordable healthcare, political conflict and instability, warfare, food insecurity, intimate partner violence, body image issues, discrimination, declining social connection, environmental threats and more.
While young people experience these stressors and the pandemic uniquely affected this group, “unfortunately we don’t have much data on the causes of this increase among youth,” Santomauro said.
Seeking help and improving access
Experiences with mental health and access to care vary significantly, and much of the burden for improvement lies with policymakers and other health authorities, experts said. “Concerningly, this increase in burden has not been accompanied by proportional expansion of mental health services,” the authors wrote. “Responding to the mental health needs of our global population, especially those most vulnerable, is an obligation, not a choice.”
But Santomauro and the other experts do have some advice that may help anyone struggling, including talking to a professional about different therapies, medications, and other support. Improving lifestyle factors such as diet, social connection, exercise, sleep, hobbies, and work-life balance, when possible, are also critical, experts said.
