The word “recovery” has been defined in various ways in the mental health field.1 In this chapter, recovery is defined in terms of a person’s symptom status in the context of a diagnosed mental disorder episode; the focus is on MDD in clinically referred children and adolescents. A major goal is to summarize what is known about recovery from and recurrence of MDD episodes in juvenile samples, along with information about sociodemographic and clinical predictors of recovery and recurrence.
Reviews of research on depression in adults and youths concur that MDD episodes are associated with very high rates of recovery and almost as high rates of recurrence.2-6 Thus, recovery from the disorder may well be an elusive goal. Furthermore, although no single consistent predictor of recovery and recurrence has emerged, the strongest predictors typically reflect nonmodifiable attributes (e.g., aspects of clinical history). Additionally, efforts to prevent recurrent depression in adults have not had the expected, broad-spectrum benefits.2 Therefore, this chapter also proposes that, using a developmental and multiperspective approach, depression research should focus on modifiable risk factors and mechanisms that are relevant to prevention (and early intervention). This approach will be illustrated with findings from a program of research that has targeted emotion regulation and related physiological constructs as core factors in the risk and recurrence of juvenile-onset MDD.
Why focus on juvenile-onset depression? Although the extant literature on depression mostly concerns adults, there has been increasing acknowledgment of the existence of juvenile-onset depression (JOD). The JOD variant of depression accounts for a notable portion of depressed cases in general population samples.7,8 In clinical samples, JOD has been shown to have a worse long-term course than depression with first onset in adulthood.9 The worse clinical course associated with JOD probably reflects, in part, its adverse effects on youngsters’ educational and social development.10 All in all, therefore, a better understanding of JOD has important public health implications.
Why focus on clinically referred depressed youths? It is widely believed that findings on clinically referred samples have limited usefulness because they cannot be generalized to the population. Indeed, in community samples, youths meeting diagnostic criteria for MDD typically have milder forms of depression than do clinical cases, as suggested by shorter episodes and lower rates of recurrence.711-14 The latter findings may partly account for the fact that the majority of depressed youths and young adults in community samples do not seek or receive mental health services.7 However, depressed children and adolescents who end up in treatment settings are the ones who pose the greatest challenges to the mental health services sector. Thus, further information about them is highly relevant both to treatment and prevention initiatives.
Why focus on risk factors or risk mechanisms in JOD? While the recurrent nature of MDD in adults has long been known,2-3,6 this characteristic has now been verified in JOD.5 Thus, preventing first and later episodes of depression in youths has taken on particular urgency, along with the need for a better understanding of risk factors or mechanisms.3 Indeed, notable strides have been made in delineating risk factors for depression, including various psychological traits and contextual factors.15,16 However, studies have typically focused on single unidimensional variables, most of which have limited developmental applicability.
This chapter will illustrate a research approach to JOD risk that considers the developmental context of key variables from the start, along with the interrelations of physiologic and psychological-behavioral systems. This particular research initiative has come to focus on the ability to attenuate one’s own sad, dysphoric affect (mood repair), which is known to be impaired among juveniles and adults with MDD, and has promise as an indicator of risk for eventual depression. As a self-regulatory skill, mood repair is partly gated by parasympathetic nervous system processes, which are typically indexed via measurement of cardiac vagal control (CVC)or respiratory sinus arrhythmia(RSA). Importantly, both mood repair and CVC/RSA are developmentally mediated: they already are at play in infancy, have been studied across subsequent development, and contribute to adaptive functioning throughout the life span.17-23 Thus, focusing on mood repair in depression risk can readily link outcomes and functioning across childhood, adolescence, and adulthood; enable the simultaneous study of behavioral and physiological aspects of a key construct in affect experience; and can provide a new perspective on recovery and recurrence in MDD.