DEPRESSIVE DISORDERS IN CHILDREN & ADOLESCENTS

- - - Epidemiology :
The point prevalence rate of depression in prepubertal children ranges from about 1-3% and from 3-9% in adolescence.  Although there is no clear difference in prevalence rates between genders in prepubertal children, females have been consistently identified as becoming at a higher risk for depression after the onset of puberty.  Studies have generally demonstrated that females are twice as likely to suffer from depressive illness by older adolescence compared to males.  Few studies have assessed large enough samples of minority youth to give precise estimates of prevalence differences varying by ethnicity. Low socioeconomic status has also been demonstrated to be a risk factor of psychopathology in youth, including depression.

Less research has been done in attempt to ascertain the incidence rate of depressive disorders in children and adolescence. Of the published studies assessing incidence rates of depression in youths, most primarily target adolescent samples. For example, Garrison et al. (1997) found a one-year incidence rates of about 3% for both Major Depression and Dysthymic Disorder in their school-based sample of young adolescents aged 11-16 years.  Lewinsohn et al. (1993) found a one-year incidence rate of 8% for Major Depressive Disorder, and a low rate of 0.8% for Dysthymic Disorder in their school-based sample of older high school students.

- - - Clinical Features :
Depression in children and adolescents can present as a component of many different clinical problems that are common reasons for referral to mental health professionals.  Some of the more common clinical presentations include a distinct and enduring mood change, school problems, family conflict, suicidal crisis, increased use of illicit substance abuse, and frequent somatic complaints. The depressed child may be irritable and grouchy, complain of feeling sick, and refuse to go to school. It is also common for depressed youths to experience a decline in academic performance and school attendance, which may at times be the impetus for parents to seek treatment for their child or adolescent.  Symptoms of depression in children and adolescents include: persistent sad or irritable mood, loss of interest in activities previously enjoyed, significant change in appetite or body weight, difficulty sleeping, loss of energy, psychomotor retardation or agitation, feelings of worthlessness or inappropriate guilt, difficulty concentrating, and recurrent thoughts about death or suicid.

- - - Possible Causes :
There is no clearly defined single cause of most or even many cases of pediatric depression.  Research with pediatric populations has identified a number of variables that can be considered risk factors or promising etiologic correlates of depression.  Biological, psychological, and social/environmental variables have been identified as risk factors for the development of depressive disorders in children and adolescents.  Some of these risk factors include biological correlates such as temperament, neuroendocrine factors, brain anatomy, and genetics.  In fact, childhood depression is associated with a family history of mood disorders and other psychiatric conditions. The psychological correlates of depression include a pessimistic or negative cognitive style, experiencing negative life events, and child abuse.  Depressed youth often have low self-esteem and view themselves and the world with pessimism.  Social/environmental factors such as poverty, parenting behavior, and peer environment can also influence the development of depression in youth.

- - - Evaluation :
Making an accurate diagnosis of a mood disorder in children and adolescence is a complicated task that requires considerable training and experience.  Although the criteria for making a diagnosis of depressive disorder in youth and adults are highly similar, the process of diagnostic evaluation is somewhat different. In addition to the interview with the identified patient, a diagnostic evaluation with children and adolescents requires greater emphasis on collateral sources of information. These collateral sources may include interviews with parents, discussions with school officials and teacher, reports from the child’s primary health care provider, as well as interviews with concerned family members or adults who are well informed about the child’s life and habits.  Additionally, diagnostic evaluation is complicated by limitations in the cognitive or verbal abilities of younger patients.  Young children may have difficulty recognizing and understanding the meaning of some symptoms as well as communicating their emotional and psychological experience to others.  Because multiple sources are used to make a diagnostic evaluation on a child or adolescent, it is common to get conflicting reports from the parents and the youth. Current preference is to use the “OR” rule, where a symptom or diagnosis is counted as present if either the parent or the child informant reports that it is present, because it is assumed that both parties contribute meaningful data to the assessment (Bird et al. 1992).

- - - Treatments :
Treatment for depressive disorders in children and adolescents often involves psychotherapy, medication, or the combination of psychotherapy and medication treatments.  Two short-term psychotherapies that have been found to be successful in treating depression in youths are cognitive behavioral therapy (CBT) and interpersonal psychotherapy (IPT).  Cognitive behavioral therapy focuses on interventions that attempt to alter negative styles of thinking and behaving often associated with depression. Research findings indicate that CBT is superior to other kinds of treatments for treating depression in adolescents (Brent et al. 1997), however, CBT at this point has not be shown to be superior to other treatments in prepubertal youth.  One possible explanation for this finding is that pre-adolescents are not cognitively mature enough to take advantage of the cognitive behavioral treatment.  Interpersonal psychotherapy focuses on the patient’s current interpersonal relationship roles and conflicts and has been shown to be successful for adolescents in terms of reducing depressive symptoms and improving overall social functioning (Mufson et al. 1999).

Some research shows that antidepressant medications can be effective in treating children and adolescents with depressive disorders. However, in general, there has been less research done to examine the safety and efficacy of psychotropic medications for the treatment of depression in children and adolescents than is available for adults. Currently none of the antidepressant medications available for use by physicians has been approved by the Food and Drug Administration (FDA) for the treatment of depressive disorders in children or adolescents. However, recently a few studies have been completed that suggest that serotonin specific reuptake inhibitors (SSRI’s) may be safe and effective in the treatment of depressed children and adolescents.  Currently, randomized controlled clinical trials with the agents Fluoxetine (PROZAC) and Paroxetine (PAXIL) have been published reporting that youth treated with SSRI medications report more robust remission of depression symptoms over the short run (8-10 weeks) than youth treated with a placebo sugar pill.  There are no adequately designed published studies at this point that unequivocally demonstrate the safety and efficacy of these medications over a longer period of time (such as months or years) making caution necessary in the use of these medications in young people.
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Currently there are no adequate studies that have directly compared youth treated with psychotherapy versus medications versus combination therapies to guide clinicians and parents in selecting the best options for treatment. The National Institute of Mental Health (NIMH) is sponsoring a large study for adolescents with depression (Treatment for Adolescents with Depression Study-TADS) which will compare outcomes over 18 months for subjects treated with medication therapy (fluoxetine), psychotherapy (CBT) or combination medication/CBT treatment.