Not surprisingly, it was only in the 1980's that mood disorders in children were included in the category of diagnosed psychiatric illnesses.

How Prevalent are Mood Disorders in Children and Adolescents?

• 7-14% of children will experience an episode of major depression before the age of 15.
• 20-30% of adult bipolar patients report having their first episode before the age of 20.
• Out of 100,000 adolescents, two to three thousand will have mood disorders out of which 8-10 will commit suicide.

Depression

There is emerging evidence that major depression can develop in prepubertal children and that it is a significant clinical occurrence among adolescents. Recent epidemiologic studies have shown that a large proportion of adults experience the onset of major depression during adolescence and early adulthood.

By studying high-risk populations for developing childhood mood disorders, researchers hope to learn more about the onset and course of depression. Myrna M. Weissman, Ph.D. of Columbia University (a NARSAD Established Investigator and 1994 Selo Prize Co-Winner) has found an increased prevalence of major depression as well as a variety of other psychiatric problems in the children of depressed parents compared with those of normal parents. Specifically, she has discovered that the onset of major depression was significantly earlier in both male and female children of depressed parents (mean age of 12.7 years) compared with those of normal parents (mean age, 16.8 years). She has also observed sex differences in rates of depression to begin in adolescence. Before 10 years of age, she found a low frequency and equal sex ratio, however by 16 years of age, there was a marked increase in major depression in girls, as compared to boys of the same age.

The essential features of mood disorders are the same in children as in adults, although children exhibit the symptoms differently. Unlike adults, children may not have the vocabulary to accurately describe how they feel and, therefore may express their problems through behavior. The following behaviors may be associated with mood disorders in children:

• In Preschool Children:
  • Somber Appearance, almost ill-looking; they lack the bounce of their nondepressed peers. They may be tearful or spontaneously irritable, not just upset when they do not get their way. They make frequent negative self-statements and are often self-destructive.
• In Elementary School-Aged Children and Adolescence:
  • Disruptive behavior, possible academic difficulties, and peer problems. Increased irritability and aggression, suicidal threats, and worsening school performance. Parents often say that nothing pleases the children, that they hate themselves and everything around them.

Bipolar Disorder

There has been a great deal of diagnostic uncertainty surrounding bipolar disorder in children. This may be caused by a major difference in the way mania is expressed in bipolar children versus adults. A look back at the histories of adults with bipolar symptoms often shows that mood swings began around puberty, however there is a frequent 5-to-10 year lag between the onset of symptoms and display of the disorder serious enough to be recognized and require treatment, resulting in the under diagnosis of bipolar disorder.

Unlike adult bipolar patients, manic children are seldom characterized by euphoric mood. Rather, the most common mood disturbance in manic children may be better described as irritable, with "affective storms" or prolonged and aggressive temper outbursts. For example, a study by Gabrielle A. Carlson, M.D. of State University of New York-Stony Brook, found that bipolar children under the age of 9 had more irritability, crying, and motor agitation as compared to older bipolar children, who were more likely to have "classically manic symptoms" such as euphoria and grandiosity. In addition, it has been suggested that the course of childhood-onset bipolar disorder tends to be chronic and continuous rather than episodic and acute, as is the adult form of the disorder.

Other aspects that make diagnosing bipolar disorder in children difficult is the frequency with which bipolar disorder is mistaken for attention-deficit hyperactivity disorder (ADHD), conduct disorder (which includes symptoms of socially unacceptable, violent or criminal behavior), or schizophrenia.

Bipolar Disorder vs. Other Childhood Disorders

ADHD and bipolar disorder have many overlapping features which include: distractibility, inattention, impulsivity, and hyperactivity. However, bipolar disorder has several differentiating features, which include: psychosis, depression, aggression, excitability, rapid mood swings, inappropriate affect and disregard for feelings of others.

Conduct disorder overlaps with bipolar disorder on symptoms such as: impulsivity, shoplifting, substance abuse, difficulties with the law and aggressiveness . However, in bipolar disorder, some distinguishing factors include: antisocial behavior with elevated or irritable mood and lack of peer group influence.

When comparing schizophrenia and bipolar, their common symptoms include: grandiose and paranoid delusions and hallucinatory phenomena. However, in schizophrenia, differentiating features include: thought disorder and bizarre delusions.

The widely accepted belief that childhood-onset mania is rare has recently been challenged. Many researchers including Janet Wozniak, M.D. of Harvard Medical School (a NARSAD Young Investigator) have shown a major overlap in the symptoms of mania and ADHD. Dr. Wozniak believes that this overlap may be responsible for the under identification and misdiagnosis of bipolar disorder. In her study of clinically referred children, she found 16% to have mania with irritable and mixed moods (i.e. with symptoms of depression and mania occurring simultaneously). Also, she found that the children meeting the criteria for mania frequently also met the criteria for ADHD (the rate of ADHD in children with mania was 98%, while the rate of mania in children with ADHD was only 20%).

Schizophrenia has also been found to be mistaken for manic depression in adolescents. Despite the fact that psychotic features are a well-established part of adolescent manic-depressive illness, many clinicians continue to believe that thought disorder, grandiosity, and bizarre delusional and hallucinatory phenomena are distinctively characteristic of schizophrenia. Difficulties often arise in differentiating blunted from depressive affect and apathy from depression-induced delay in response time to questions.

Treatments

It is important for children suffering from mood disorders to receive prompt treatment because early onset places children at a greater risk for multiple episodes of depression throughout their life span. Children who experience their first episode of depression before the age of 15 have a worse prognosis when compared with patients who had a later onset of the disorder.

At the present time, there is no definitive treatment for the spectrum of mood disorders in children, although some researchers believe that children respond well to treatment because they readily adapt and their symptoms are not yet entrenched. Treatment consists of a combination of interventions. Medications can be useful for cases of major depression or childhood onset mania, and psychotherapy can help children express their feelings and develop ways of coping with the illness. Some other helpful interventions that may be used are educational and family therapy.

Children suspected of mood disorders should be evaluated by a child psychiatrist, or if one is not available an adult psychiatrist who has experience in treating children. It is important that the clinician has had special training in speaking with children, utilizing play therapy, and can treat children in context of a family unit.

Suicide

An estimated 2,000 teenagers per year commit suicide in the United States, making it the leading cause of death after accidents and homicide. According to David Schaffer, M.D., of Columbia University ( a NARSAD Established Investigator), suicidal behavior is uncommon before puberty, with the incidence of suicide attempts reaching its peak at around age 15 and becoming less common by the late teens. Studies of adolescent suicides in New York, Pittsburgh and Finland indicate that approximately 90 percent of the teenagers who commit suicide have a psychiatric diagnosis, most often a form of mood disorder and/or alcohol or substance abuse.

As in adults, suicide attempts occur more often in females (a ratio of 9 to 1), with overdose and wrist-cutting the most common means. Completed suicide occurs more often in males (a ratio of 3 to 1), usually white males, with shooting (62 percent) and hanging (19 percent) the most common means.

Biological Theories on Suicide

A number of biological theories are emerging to explain suicidal behavior. The available evidence points to hyposerotonergic functioning in studies of both completers and attempters. In suicide victims' brains, an increase in postsynaptic 5-hydroxytryptamine type 2 (5-HT2) receptors was found in the prefrontal cortex, suggesting that a compensatory increase in receptor density occurred in response to decreased serotonin release. The most robust findings in postmortem brains have been the measurements of low levels of serotonin (5-HT) and its major metabolite, 5-hydroxyindoleacetic acid (5-HIAA). Those findings were localized to the brainstem (the level of cell bodies) and were not found in the cortex. Completers have also shown alterations in noradrenergic (the activation of norepinephrine in the transmission of nerve impulses) but not cholinergic (of autonomic nerve fibers) pathways.

Several clinical studies have also found evidence of family histories of suicidal behavior, suggesting the likelihood of genetic factors playing a role in suicide. Twin studies provide evidence for genetic transmission of this vulnerability as twins share the same environment but differ in number of genes shared. Of 150 sets of twins reported in which at least one twin committed suicide, all 10 of the pairs in which both committed suicide were identical twins, and half of those were concordant for the same psychiatric illness.

Identifying the Vulnerable

Dr. Schaffer believes that screening out the vulnerable groups of children and adolescents for the risk factors of suicide and then referring them for treatment is the best way to lower the staggering teenage suicide rate. Students are regarded as high-risk if they have indicated suicidal ideation within the last three months, if they have ever made a prior suicide attempt, or if they indicate severe mood problems, excessive alcohol consumption or substance use.

In summary, mood disorders in children and adolescents are much more common than was originally estimated. This underestimation was primarily due to the diagnostic confusion surrounding overlapping symptoms from other childhood disorders and the difference in the expression of mania in children versus adults. Many research efforts are underway to better diagnose and identify the children and adolescents who are at risk for mood disorders. It is hoped that by identifying the most vulnerable individuals and providing them with treatment, we will finally start to see a decline in the staggering suicide rates for adolescents.