13 - Natural history of mood disorders in children and adolescents

Summary

Knowledge of the natural history of an illness is critical to understanding its origins and to optimizing its management. Over the past 15 years or so, data have been accumulating steadily on the course and outcome of juvenile affective conditions. The main purpose of the present chapter is to review these studies. The chapter is divided into five parts. The first part is concerned with the risk of recurrence of juvenile depression and the second part with the mechanisms that might be involved. The third part describes the prospects for recovery. The fourth part reviews the natural history of other juvenile affective disorders, principally bipolar disorder. The chapter concludes with a discussion of some of the clinical implications of these research findings.

Continuity and recurrence of depression

Continuities in the short term

Many studies of clinical samples have reported that young people with a depressive disorder have a high risk of recurrence or persistence (King & Pittman, 1970; Kovacs et al., 1984a; Asarnow et al., 1988; Goodyer et al., 1991; McCauley et al., 1993; Emslie et al., 1997b). For example, Kovacs and colleagues (1984a) undertook a systematic follow-up of child patients with a major depressive disorder, a dysthymic disorder, an adjustment disorder with depressed mood, and some other psychiatric disorder. The development of subsequent episodes of depression was virtually confined to children with major depressive disorders and dysthymic disorders. Thus, within the first year at risk, 26% of children who had recovered from major depression had had another episode; by 2 years this figure had risen to 40%; and by 5 years the affected cohort ran a 72% risk of another episode.