Link between asthma and depressive disorders found

Nov 6 2007

Young people with asthma are about twice as likely to suffer from depressive and anxiety disorders than are children without asthma, according to a study by a research team in Seattle.

Previous research had suggested a possible link in young people between asthma and some mental health problems, such as panic disorder, but this study is the first showing such a strong connection between the respiratory condition and depressive and anxiety disorders. The findings appear in the November issue of the Journal of Adolescent Health.

The study was conducted by researchers at the University of Washington School of Medicine, Group Health Cooperative, and Seattle Children's Hospital Research Institute. The researchers interviewed more than 1,300 youths, ages 11 to 17, who were enrolled in the Group Health Cooperative health maintenance organization. Of the participants, 781 had been diagnosed with or treated for asthma, and the rest were randomly selected youths with no history of asthma.

About 16 percent of the young people with asthma had depressive or anxiety disorders, the researchers found, compared to about 9 percent of youth without asthma. When controlling for other possible variables, youth with asthma were about 1.9 times as likely to have such depressive or anxiety disorders.

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.

Young people with depressive and anxiety disorders often find it harder to manage their asthma and describe more impaired physical functioning because of the combination of asthma and a depressive or anxiety disorder, the researchers said. 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."

In addition to exploring the link between asthma and depressive and anxiety disorders, researchers found other variables that further increase the risk of such disorders. Female respondents were 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.