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Some experiences of sadness, grief, or depressed mood arise during
the course of most children’s lives. Divorces, the death
of a grandparent, the departure of a close friend, or a failed hope—all
are common and upsetting. However, there has been increasing recognition
that some children and adolescents suffer from serious and pervasive
disorders related to their mood and that these disorders are associated
with significant morbidity (ie, impairment in psychosocial function,
low self-esteem) and mortality (ie, intended suicide or “accidental” death secondary
to an impulsive behavior such as driving while intoxicated). Consequently,
the critical clinical task is to differentiate children and adolescents
with serious disorders from the larger group of children and adolescents
who have some symptoms of sadness or grief but who are not clinically
depressed. Since the diagnosis and risk assessment depends on emotional
information gleaned from an interview, it can be extremely difficult
for a clinician to differentiate between those children and adolescents
with serious mood disorder and those who are profoundly and acutely
upset in response to a combination of adverse circumstances.
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Because our understanding of the pathophysiology of emotional
dysregulation is just emerging, diagnosis of major
depressive disorders relies primarily on clinical history and observed
mental status. There are few reliable tests to assist or to confirm
a diagnosis. Current knowledge is based on the best available data
from clinical studies, epidemiological research, and careful observations
of longitudinal course.
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Currently, depressive illnesses are classified into three broad
categories: depressive disorders, dysthymic disorder, and bipolar
affective disorder or cyclothymic disorder (see Table 93-1).
Estimates of the point prevalence of major depression are approximately
1.5% to 2.5% in prepubertal children, increasing
to 3% to 8% during adolescence. Bipolar affective illness
is estimated at a point prevalence of 0.2% to 0.4% among
prepubertal children, increasing to approximately 1% among
adolescents. Depressive illnesses do not show gender differences
in prepubertal children; however, at puberty, there is a significant
increase in major depression among females, resulting in a female-to-male
ratio of 3:1 during adolescence. Some research suggests that early
onset of puberty increases the risk of depression in girls.1 Bipolar
disorders are equally common in males and females throughout the
life cycle.
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