Predictors of response to treatment in children and adolescents with mood disorders

Depression and bipolar disorder are frequently chronic disorders, with onset often beginning in childhood. Mood disorders are becoming more recognized in children and adolescents, and treatment of these disorders has received much attention, particularly in the past 10 years. Recent studies have demonstrated efficacy of antidepressant medications (particularly SSRIs) and specific psychotherapies (primarily CBT). Rates of remission (little or no symptoms) in these studies, however, have remained quite low (35% to 40% in most acute studies). Furthermore, recurrence is common in this population, and affects 40% to 50%. Early onset mood disorders are also associated with increased risk of developing other psychiatric disorders, substance abuse, and suicide, and having poor academic, work, and social functioning. The lifelong implications are serious. Identifying factors that may predict response to treatment, both in general and to specific treatments, may lead to improved outcomes for these patients. Unfortunately, studies have typically been inconsistent. Most studies do not identify demographic variables as predictive of outcome, although older age has been associated with poor prognosis in several studies. Psychosocial factors have yielded some results, particularly with regard to family environments. Generally, intact families with positive interaction styles and less dysfunction have been associated with better outcomes. Psychiatric disorders among parents not only predicts the development of the disorder, but is also associated with poorer prognosis. Finally, several clinical factors have been linked to poorer outcome in children and adolescents with mood disorders. More frequent episodes, increased severity (particularly suicidality and psychosis), and comorbid disorders are likely to lead to fewer recoveries, longer episodes, and increased rate of recurrence. Recent attention has focused on mediators and moderators of outcomes to treatment. In general, the theory is that enumerable factors contribute to the course of an individual's mood disorder, but that by identifying some of the variables that have more impact may allow for more specific or modified treatments to improve outcome. Many of the predictive factors explored in this article are examples of mediators and moderators that affect outcome. Each one alone may not provide definitive answers for predicting response to treatment, but each must be taken into account at the outset of treatment. It is clear that treatments must be individualized for each patient. Furthermore, selecting only one treatment exclusively for patients may hinder progress. The first step is to attempt to identify some of the underlying causes and the consequences of the disorder itself (i.e., decreased social interaction). The next step in successful treatment is to address both the causes and consequences of the disorder, through medication, psychotherapy, skills training, family intervention, or any other methods needed to assist the child to begin functioning better in all domains (social, academic, work, family, and so forth). Such a biopsychosocial approach to treatment of these disorders will likely improve overall outcome.