[Depression in children and adolescents].
The prevalence of major depression in preschool is less than 1 procent, in school-age children about 2 percent, and in adolescents about 4.7 percent. While as no significant sex differences have been reported among preadolescents, studies of adolescents have reported 2 to 3 times higher rates of depression. The most frequent course of depression is chronic and persistent, the mean length of depressive episode being 30 weeks. Depressed children and adolescents have impaired psychosocial functioning and school problems. Relapse occurs at a high frequency for depressed patients. The high recurrence of depression in children and adolescents calls for a long-term management in these age-groups.