(Reuters Health) - Children and young adults with chronic conditions like asthma, diabetes, and ADHD may be more likely to develop mental illness than youth who don’t have physical health problems, a U.S. study suggests.

Researchers followed more than 48,000 youth without any diagnosed mental health disorders for two years, starting when they were between 6 and 25 years old. Overall, 14.7% had a chronic physical health problem that either limited their ability to navigate daily life or required ongoing treatment.

Overall, 7.8% of the study participants developed a mental health problem over the course of the study. Children and young adults with a chronic physical health problem were 51% more likely to be diagnosed with a mental illness than youth without issues like asthma, diabetes, and attention deficit/hyperactivity disorder, or ADHD.

“A surprising amount of this difference is explained by limitations in the ability to participate in school, work, and social activities,” said study leader Dr. John Adams of the Cambridge Health Alliance in Massachusetts.

Among all the study participants, 1.8% reported activity limitations. Youth with chronic physical health problems were more than 3 times more likely to have limitations than other participants.

“This matters because it shows what a powerful impact growing up with physical illness can have on mental health and also highlights a potential mechanism which could help future efforts to prevent mental illness in this population,” Adams said by email.

In the study, mental health conditions were more common among older youth, suggesting that living with conditions like asthma or diabetes might take a psychological toll that gets worse over time, researchers note in Pediatrics.

The cumulative two-year rates of mental health diagnoses were 5.6% among kids 6 to 11 years old, but climbed to 7.4% among participants 12 to 18 years old and 10.1% among young adults 19 to 25 years old.

The most common mental health diagnoses in the study were anxiety, mood disorders and behavior disorders.

Youth with chronic physical health problems were 51% more likely to develop anxiety, 70% more likely to develop mood disorders, and 54% more likely to develop behavior disorders, the study found.

The study wasn’t a controlled experiment designed to prove whether or how chronic physical health problems might directly cause psychological problems in young people.

One limitation of the study is the relatively brief follow-up period, the authors note. It might take more than 2 years for mental health disorders to become apparent, particularly with the youngest study participants.

Another drawback is that the researchers relied on surveys of parents to gather data on young people with both physical and mental health problems, and it’s possible this might not always reflect the conditions that children had.

Even so, the results underscore the importance of parents keeping close watch for symptoms of mental health disorders in kids with chronic physical health problems, said Dr. Ethan Benore, head of the Center for Pediatric Behavioral Health at Cleveland Clinic Children’s in Ohio.

“Children with a chronic medical condition may be at a greater risk of developing a mental health issue,” Benore, who wasn’t involved in the study, said by email.

“For this reason, parents should monitor their child’s well-being, seeking assessment and early intervention if any concerns arise,” Benore added. “Educating children and supporting them in their psychosocial development should be a part of treating any chronic health condition of childhood.”

SOURCE: bit.ly/2RrZQBO Pediatrics, online June 14, 2019.