Mental health disorders disrupt children's transition to adulthood, study finds

Common childhood mental health disorders — such as anxiety, depression and behavioural problems like ADHD — are associated with a disrupted transition to adulthood, even if the disorders don't persist into adulthood, new research from Duke University suggests.

One of the things this suggests is that this is an iceberg. There are a few kids that pop above the surface, but there are many more below the water.- William Copeland, researcher

Dubbed as the Great Smoky Mountains Study, the research followed 1,420 children — aged nine, 11 and 13 — in 11 predominantly rural counties in North Carolina for 17 years, from 1993 to 2010. The children were assessed every year until they turned 16, and then again at 19, 21 and 25.

The study found that children with a diagnosable disorder were six times more likely to experience at least one of what researchers described as adverse outcomes in adulthood, such as addictions, incarceration, teenage pregnancy and high-school dropouts. They were also nine times more likely to experience two or more of these outcomes.

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These outcomes, covering health, legal, financial and social domains, are indicators of impeded functioning over a long period of time, researchers said.

"The kind of outcomes we were looking at in adulthood were things that we thought were real signs of functioning having been compromised," said William Copeland, a clinical psychologist and epidemiologist who co-authored the study.

The increased risk was not limited to children who received a full mental health diagnosis, however.

The study also looked at children who experienced psychiatric symptoms but didn't meet the criteria for a full psychiatric disorder. These "sub-threshold cases" were three times more likely to experience adverse outcomes compared with those who have no symptoms during childhood, and five times more likely to experience two or more outcomes.

"I think what this suggests is these kind of disorders and these types of problems can put these kids on certain trajectories that it's really difficult to get off of," Copeland said.

The results were independent of adult psychiatric problems, the study found. They also persisted after researchers accounted for psychosocial factors during childhood, such as sex, race, low socioeconomic status, family dysfunction, family instability and maltreatment.

Researchers surprised by magnitude 

The study was published online on Wednesday in JAMA Psychiatry, an international peer-reviewed medical journal of the American Medical Association. 

The researchers expected to find increased risks and disadvantages in children with mental health issues, but Copeland said he was still surprised by the magnitude of the difference.

"When we saw that these kids had six times higher rates of some of these really serious outcomes, outcomes that anyone would agree could disrupt function for a long period of time, that very much surprised me," he said.

"And when we saw that these effects were maintained after accounting for a lot of those environmental characteristics that we've all come to associate with poor outcomes over time, this definitely gave me pause."

The study is another reminder that childhood mental health disorders not only cause distress for children and parents, but also have implications years down the road, Copeland said. 

Recognizing sub-threshold cases

It also calls for more recognition for children in the sub-threshold cases, who make up a much larger group compared to those with a full diagnosis.

"One of the things this suggests is that this is an iceberg. There are a few kids that pop above the surface, but there are many more below the water," Copeland said.

Interventions for these children may forestall future impairment, distress and societal costs, the researchers suggested.

The researchers also found that only 40 per cent of the children that had a diagnosed mental health disorder received some sort of treatment. And even for those children, the treatment — such as seeing a counsellor or a social worker at school — wasn't ideal. Few of them were seeing mental health specialists.

"I think there's much more that we can do in mental health public policy," Copeland said. "But of course that's going to take resources."

The study is continuing and researchers are currently interviewing participants in their 30s. They also hope to identify children who are more likely to have adverse outcomes as adults and require intensive treatment.

This study was funded by the National Institute of Mental Health, the National Institute on Drug Abuse, the Brain and Behavior Research Foundation (Early Career Award to Dr. Copeland), and the William T. Grant Foundation.