Epidemiology, comorbidity, and course of adolescent depression

Abstract

Until recent years, depression in adolescents had received little research attention. Indeed, there was a prevailing assumption that depressive disorders rarely occurred in children and adolescents. This view stems from the theoretical notion that children and adolescents are too cognitively immature to be depressed, and the concept that psychopathological manifestations and difficulties represent normal developmental processes of childhood and adolescence (Rie, 1966). Nevertheless, a handful of investigators of depression in adolescence during the late 1970s and early 1980s had not only established the presence of depression at this developmental stage, but their work had also delineated some of the psychosocial impairments associated with depression. The late 1970s was also associated with an increasing recognition that children and adolescents exhibit the essential features of adult depression. This change in viewpoints is reflected in the use of the same adult criteria for depressive disorders in children and adolescents in the third edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-III; American Psychiatric Association; APA, 1980) and its subsequent revisions (DSM-III-R; APA, 1987; DSM-IV; APA, 1994). Depressive disorders are characterized by the presence of depressed moods along with a set of additional symptoms, persisting over time, and causing disruption and impairment of function. In DSM-IV (APA, 1994), depressive disorders fall under the category of major depressive disorder, dysthymic disorder, and depressive disorder not otherwise specified. Major depressive disorder (MDD) denotes a severe, acute form of depressive disorder (DSM-IV; APA, 1994). The disorder is diagnosed when the adolescent has experienced at least five of the following nine symptoms nearly every day for at least a two-week period at a level that represents a change from previous functioning: depressed mood (or can be irritable mood in children and adolescents); markedly diminished interest or pleasure in all, or almost all activities; significant weight loss or weight gain, or decrease or increase in appetite (in children, consider failure to make expected weight gains); insomnia or hypersomnia; psychomotor agitation or retardation; fatigue or loss of energy; feelings of worthlessness or excessive or inappropriate guilt; diminished ability to think or concentrate, or indecisiveness; and recurrent thoughts of death, recurrent suicidal ideation without a specific plan, or a suicide attempt or a specific plan for committing suicide. At least one of the two core