The study was conducted at the University Of Washington School Of Medicine, Group Health Cooperative, and Seattle Children's Hospital Research Institute. It involved more than 1,300 kids between the ages of 11 to 17. Of the participants, 781 had been diagnosed with or treated for asthma, and the rest were randomly selected youths with no history of asthma.
The study found that about 16 percent of the young people with asthma had depressive or anxiety disorders as compared to about 9 percent of youth without asthma. When controlling for other possible variables, kids with asthma were found to be about 1.9 times as likely to develop such disorders.
Girls were found to be at a greater risk of depressive and anxiety disorders, as were youth living in a single-parent household, those who had been diagnosed with asthma more recently, and those with more impairment in asthma-related physical health.
Researchers tested for several depressive and anxiety disorders, including depression, a mood disorder called dysthymia, panic disorder, generalized anxiety disorder, separation anxiety, social phobia, and agoraphobia. These disorders are somewhat common in youth, and are associated with high risk for school problems, early pregnancy, adverse health behaviors like smoking or lack of exercise, and suicide.
The study also says that young people with depressive and anxiety disorders often found it harder to manage their asthma and describe more impaired physical functioning because of the combination of asthma and a depressive or anxiety disorder. Youth with asthma and one of the disorders are also more likely to smoke, making their asthma more difficult to treat.
"Physicians treating young people with asthma should realize that those children are at a greater risk of depressive and anxiety disorders, and should try to educate patients and their families about this increased risk," said Dr. Wayne Katon, professor and vice-chair of psychiatry at the UW School of Medicine, and corresponding author of the study.
"The primary care system is correctly identifying only about 40 percent of the cases in which children with asthma also have a psychiatric disorder. We should improve our screening for these disorders, and develop effective treatment programs for affected patients that address both asthma and the depressive or anxiety disorder," he said.
The study was published in the November issue of the Journal of Adolescent Health.