(USA TODAY) -- Children of parents with anxiety disorders are up to seven times more likely than others to develop anxiety problems themselves, research shows, and children of depressed parents also are at high risk for becoming depressed.

Two new studies suggest that talking to therapists can break the cycle, reducing the risk of mental health problems in children and teens.

Both studies released this week focused on "cognitive behavior therapy," in which patients learn to reframe the way they think about upsetting events to avoid falling into a depressive spiral.

Adolescence could be the best time to try to prevent depression, because most depressed adults say their problems started in their teen years, says Judy Garber of Nashville's Vanderbilt University, author of a study in today's Journal of the American Medical Association. About one in five teens experience depression by age 18.

Depressed children are more likely to have trouble in school and are at increased risk for suicide or substance abuse, Garber says.

Garber's study focused on high-risk teens whose parents had a history of depression. All 316 of the teens already had experienced depression in the past or had some symptoms of depression when the study began. Half were randomly assigned to attend eight weekly group sessions with other teenagers.

After nine months, teens who attended group therapy were less likely to have had an episode of depression than teens who had their usual care but didn't receive therapy, the study shows. The prevention program didn't help at all, however, for teens whose parents were currently depressed, Garber says.

Children of depressed adults may feel adrift because their parents aren't able to give them the support and encouragement they need, says Bryan King, director of child and adolescent psychiatry at Seattle Children's Hospital, who wasn't involved in the study.

In addition to a genetic predisposition to depression, children may inherit their parents' negative attitudes.

In a small study from Johns Hopkins Children's Center, researchers tried to help children who weren't yet having anxiety problems. All 40 of the children, ages 7 to 12, had parents with anxiety disorders.

Researchers offered half of youngsters and their parents an eight-week course of "cognitive behavioral therapy." In these hour-long sessions, parents learned how to recognize things they were doing that might make their children anxious -- such as being overprotective or worrying out loud. Children also learned coping skills, according to the study, in the June issue of the Journal of Consulting and Clinical Psychology, released Monday.

After a year, none of the children in therapy had developed an anxiety disorder. But doctors diagnosed anxiety disorders in 30% of children in the comparison group, who were placed on a waiting list but didn't receive therapy during the clinical trial, says lead author Golda Ginsburg, a child psychologist.

Few insurers pay for cognitive behavioral therapy, but Ginsburg says she hopes her study will provide evidence that it's worth the investment.

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