MONDAY, April 4 (HealthDay News) -- A preliminary study of American kids suggests a connection between listening to pop music and suffering from major depressive disorder.

But, before you pull the battery from your child's MP3 player, know that the study did not establish a cause-and-effect relationship. And there was no clear indication whether kids who were predisposed to depression were more strongly drawn to music or, instead, faced a greater risk for depression as a result of their music exposure.

The finding also didn't nail down exactly what type of music children and adolescents in the study listened to, but rather presumed that time spent listening to music was generally spent listening to the range of pop music currently embraced by the majority of American teens.

That said, linking pop music exposure to what the study authors describe as the leading cause of disability in the world could ultimately reveal mechanisms that might reduce young people's risk for depression, the researchers said.

"Now this is a preliminary finding, and there's nothing about this that says that music is bad," said study author Dr. Brian A. Primack, an assistant professor of medicine and pediatrics at the University of Pittsburgh School of Medicine. "In fact, it may even be therapeutic, in that teens who are already depressed might be seeking a kind of solace or meaning in the kind of music that they listen to. Or it could be the other possibility, that there are certain messages in music that can unmask a predisposition to depression, or even lead teens to become depressed. We just don't know.

"What is clear is that this seems to be a really strong association," Primack added. "So this could be an interesting marker that can help us recognize depression. And it perhaps has implications for parents and health-care providers, in that it could be that noticing that a teen is listening to music constantly could be a sign of depression."

Primack and his associates report their findings in the April issue of the Archives of Pediatrics & Adolescent Medicine.

It's estimated that kids between the ages of 8 and 18 are exposed to 10 hours a day of media in one form or another, the researchers said.

To explore the possible relationship between some forms of media exposure and a risk for depression among children, the research team analyzed data that had been collected between 2003 and 2008 as part of the Child and Adolescent Depression and Anxiety Study conducted at the Western Psychiatric Institute and Clinic in Pittsburgh. The kids' ages ranged from 7 to 17.

Forty-six of the 106 mostly white participants, whose average age was 12.7 years, were experiencing a major depressive disorder episode at the time of study (as determined by an initial psychiatric interview). Of those, nearly three in four also had an anxiety disorder, while the other 60 kids had no prior history of mental illness.

Over the two-month study period, the participants (63 percent of whom were female) were interviewed by phone 12 times on five separate weekends and asked to detail their exposure to any of these five media: TV/movies, music, video games, the Internet, and printed matter (such as books, magazines and/or newspapers).

The study authors determined that age and gender had little bearing on whether or not the children were found to have major depressive disorder.

However, in terms of media exposure, the more they listened to music (via MP3 or CD players), the greater the likelihood of having major depressive disorder.

When the researchers divided media exposure into four levels, ranging from least to most exposure, they found each increasing level of music exposure was associated with an 80 percent increase in depression risk.

In contrast, exposure to print media was linked to a lower risk for depression. With each increasing level of exposure to print media, depression risk dropped by 50 percent.

TV, Internet, and video game exposure was not found to have a statistically significant association with depression risk one way or the other.

The study authors stressed that although the findings seem to confirm previous evidence of music and print's impact on teen depression, more research is needed to further explain the associations.

Michael W. O'Hara, a professor of psychology at the University of Iowa in Iowa City, cautioned that while the study made "some interesting observations," the very nature of this kind of investigation makes it difficult to isolate exactly what's afoot.

"It's very hard to control for outside influences apart from, say, music exposure," he noted. "For example, things like poverty and low socioeconomic status are associated with a risk for depression and lots of other problems, and you would have to factor that in to see how big a role that plays as opposed to simply exposure to various forms of media.

"Of course, we do know that teens and adults who are more active and more socially engaged with others are less likely to have problems with depression," O'Hara added. "So music listening could be one of those activities that encourages teens to pull back from social interaction and dwell instead on their inner life. And, yes, perhaps that could raise a risk for depression."

More information

For more on adolescent depression, visit the U.S. National Institutes of Health.