Source: ABC News
Half the population will experience a mental health disorder by the time they reach 75, a global study led by Queensland researchers has revealed.
The joint study between the University of Queensland (UQ) and Harvard Medical School tracked 150,000 adults across 29 countries, over two decades.
Depression and anxiety were the two most common disorders according to the study, published in the Lancet Psychiatry.
UQ Professor John McGrath said it was a "stark finding".
"This is a really shocking finding and a wake-up call for us," Professor McGrath said.
The three most common disorders for women were depression, a specific phobia (a disabling anxiety that interferes with daily life) and post-traumatic stress disorder.
For men the most common disorders were alcohol abuse, depression and a specific phobia.
Teenagers at 'peak risk'
Fifteen is the peak age for a mental disorder to begin, Professor McGrath said.
Anxiety, depression and substance abuse are the most common disorders among young people.
"This is when they are at school, when they are teenagers, and when they are at the greatest risk of developing mental health disorders," he said.
Of people who experience a mental disorder, half of those will acquire it by the age of 19, the study found.
"This is a really important age for people to finish their education, start their careers, start partnerships and leave their families," he said.
"We don't want mental disorders disrupting these key life events."
Professor McGrath said resources needed to be directed to young people.
"Australia has done very well with Headspace and investment in child youth mental health, but we need more. There are huge unmet needs," he said.
According to the national statistical agency, one in four Australians had a mental health disorder in 2018.
In 2020-21, about two in five Australians had experienced a mental disorder at some time in their life, according to the national statistics agency.
But unlike this "snapshot", Professor McGrath said the new research analyses the likelihood of developing a disorder over a lifetime.
"If you do a snapshot, you may find the one in four figures, but when you piece it together across your whole life span, which is what we have done, you see that it is actually one in two," he said.
'More affected than we knew'
Royal Australian and New Zealand College of Psychiatrists' Queensland chair Professor Brett Emmerson said the study shows more people are affected by mental illness than previously thought.
Professor Emmerson said funding and services may need to be reviewed.
"If half of the population will have a disorder, then you have to start looking at what treatments there are," he said.
"Early intervention is better because if you leave it, you risk the disorder becoming chronic."
By Scout Wallen, ABC News