Some teens show signs of future depression.

Certain characteristics typify teens who suffer recurrences of depression as young adults, raising researchers' hopes for devising improved depression treatments, a new study finds.

But, the current outlook for depressed teens isn't bright. The results indicate that by their early 20's, about half of these young people have again experienced depression's trademark blend of melancholy, despair, and apathy.

Adolescents destined for recurrences of depression had earlier exhibited severe symptoms of the disorder, had parents and siblings who had suffered from depression, and felt an overwhelming desire for the support and approval of others, reports a team led by psychologist Peter M. Lewinsohn of the Oregon Research Institute in Eugene.

Depressed teenage girls more often experienced recurrences than their male counterparts did, the scientists add. Emotional prospects in young adulthood proved worst for depressed girls who clashed often with their parents and had difficulty forming stable friendships.

These findings, published in the October AMERICAN JOURNAL OF PSYCHIATRY, underscore the mingled influences of biology and emotional life on depression, the scientists say.

Still, several psychological factors that might plausibly influence a teen's emotional state showed little impact on later depression, Lewinsohn notes. These attributes included having a pessimistic outlook, low self-esteem, and few supportive relatives or friends.

From a randomly selected group of 1,709 high school students in Oregon, all ages 14 to 18, the researchers identified 274 who had recovered from a single period of major depression. Those youngsters completed an initial psychiatric interview, a second interview 1 year later, and a final one after another 5 years had passed.

By the third interview, nearly half of the participants had plunged back into depression at least once. Rates of substance abuse and anxiety disorders rose more sharply in these teens than in those with no recurrences. Personality disorders associated with impulsive violence and unstable relationships also frequently appeared, the researchers say.

Only one in five of the study participants received mental-health treatment of any kind during the study.

Despite this generally bleak news, the findings offer hope for improving treatment, comment Andres Martin and Donald J. Cohen, both psychiatrists at Yale University School of Medicine, in an editorial in the same journal.

"Combinations of antidepressant medication, psychotherapy, and family interventions require more investigation," Martin says. Early, effective depression treatment may also reduce substance abuse, in his view.