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In children and adolescents, the most frequently
diagnosed mood disorders are major depressive disorder,
dysthymic disorder, and bipolar disorder. Because
mood disorders such as depression substantially
increase the risk of suicide, suicidal behavior
is a matter of serious concern for clinicians who
deal with the mental health problems of children
and adolescents. The incidence of suicide attempts
reaches a peak during the midadolescent years, and
mortality from suicide, which increases steadily
through the teens, is the third leading cause of
death at that age (CDC, 1999; Hoyert et al., 1999).
Although suicide cannot be defined as a mental disorder,
the various risk factors—especially the presence
of mood disorders—that predispose young people
to such behavior are given special emphasis in this
section, as is a discussion of the effectiveness
of various forms of treatment. The evidence is strong
that over 90 percent of children and adolescents
who commit suicide have a mental disorder, as explained
later in this section.
Major depressive disorder is a serious
condition characterized by one or more major depressive
episodes. In children and adolescents, an episode
lasts on average from 7 to 9 months (Birmaher et
al., 1996a, 1996b) and has many clinical features
similar to those in adults. Depressed children are
sad, they lose interest in activities that used
to please them, and they criticize themselves and
feel that others criticize them. They feel unloved,
pessimistic, or even hopeless about the future;
they think that life is not worth living, and thoughts
of suicide may be present. Depressed children and
adolescents are often irritable, and their irritability
may lead to aggressive behavior. They are indecisive,
have problems concentrating, and may lack energy
or motivation; they may neglect their appearance
and hygiene; and their normal sleep patterns are
disturbed (DSM-IV).
Despite some similarities, childhood depression
differs in important ways from adult depression.
Psychotic features do not occur as often in depressed
children and adolescents, and when they occur, auditory
hallucinations are more common than delusions (Ryan
et al., 1987; Birmaher et al., 1996a, 1996b). Associated
anxiety symptoms, such as fears of separation or
reluctance to meet people, and somatic symptoms,
such as general aches and pains, stomachaches, and
headaches, are more common in depressed children
and adolescents than in adults with depression (Kolvin
et al., 1991; Birmaher et al., 1996a, 1996b).
Dysthymic disorder is a mood disorder
like major depressive disorder, but it has fewer
symptoms and is more chronic. Because of its persistent
nature, the disorder is especially likely to interfere
with normal adjustment. The onset of dysthymic disorder
(also called dysthymia) is usually in childhood
or adolescence (Akiskal, 1983; Klein et al., 1997).
The child or adolescent is depressed for most of
the day, on most days, and symptoms continue for
several years. The average duration of a dysthymic
period in children and adolescents is about 4 years
(Kovacs et al., 1997a). Sometimes children are depressed
for so long that they do not recognize their mood
as out of the ordinary and thus may not complain
of feeling depressed. Seventy percent of children
and adolescents with dysthymia eventually experience
an episode of major depression6 (Kovacs et al.,
1994). When a combination of major depression and
dysthymia occurs, the condition is referred to as
double depression.
Bipolar disorder is a mood disorder in
which episodes of mania alternate with episodes
of depression. Frequently, the condition begins
in adolescence. The first manifestation of bipolar
illness is usually a depressive episode. The first
manic features may not occur for months or even
years thereafter, or may occur either during the
first depressive illness or later, after a symptom-free
period (Strober et al., 1995).
The clinical problems of mania are very different
from those of depression. Adolescents with mania
or hypomania feel energetic, confident, and special;
they usually have difficulty sleeping but do not
tire; and they talk a great deal, often speaking
very rapidly or loudly. They may complain that their
thoughts are racing. They may do schoolwork quickly
and creatively but in a disorganized, chaotic fashion.
When manic, adolescents may have exaggerated or
even delusional ideas about their capabilities and
importance, may become overconfident, and may be“fresh”
and uninhibited with others; they start numerous
projects that they do not finish and may engage
in reckless or risky behavior, such as fast driving
or unsafe sex. Sexual preoccupations are increased
and may be associated with promiscuous behavior.
Reactive depression, also known as adjustment
disorder with depressed mood, is the most common
form of mood problem in children and adolescents.
In children suffering from reactive depression,
depressed feelings are short-lived and usually occur
in response to some adverse experience, such as
a rejection, a slight, a letdown, or a loss. In
contrast, children may feel sad or lethargic and
appear preoccupied for periods as short as a few
hours or as long as 2 weeks. However, mood improves
with a change in activity or an interesting or pleasant
event. These transient mood swings in reaction to
minor environmental adversities are not regarded
as a form of mental disorder.
Conditions Associated With Depression
Roughly two-thirds of children and adolescents
with major depressive disorder also have another
mental disorder (Angold & Costello, 1993; Anderson
& McGee, 1994). The most commonly associated
disorders are dysthymia (see above), an anxiety
disorder, a disruptive or antisocial disorder, or
a substance abuse disorder. When more than one diagnosis
is present, depression is more likely to begin after
the onset of the accompanying disorder, except when
that disorder is substance abuse (Biederman et al.,
1995; Kessler & Walters, 1998). This suggests
that, in some cases, depression may arise in response
to the associated disorder. In other instances,
such as the co-occurrence of conduct disorder and
depression, the two may arise independently in response
to inadequate maternal supervision and control,
raising the possibility that parental behavior may
be a risk factor for both conditions (Downey &
Coyne, 1990; Rutter & Sandberg, 1992; Harrington,
1994).
Prevalence
Major Depression
Population studies show that at any one time between
10 and 15 percent of the child and adolescent population
has some symptoms of depression (Smucker et al.,
1986). The prevalence of the full-fledged diagnosis
of major depression among all children ages 9 to
17 has been estimated at 5 percent (Shaffer et al.,
1996c). Estimates of 1-year prevalence in children
range from 0.4 and 2.5 percent and in adolescents,
considerably higher (in some studies, as high as
8.3 percent) (Anderson & McGee, 1994; Lewinsohn
et al., 1994a; Garrison et al., 1997; Kessler &
Walters, 1998). For purposes of comparison, 1-year
prevalence in adults is about 5.3 percent (Murphy
et al., 1988; Rorsman et al., 1990; Regier et al.,
1993).
Dysthymic Disorder
The prevalence of dysthymic disorder in adolescents
has been estimated at around 3 percent (Garrison
et al., 1997). Before puberty, major depressive
disorder and dysthymic disorder are equally common
in boys and girls (Rutter, 1986). But after age
15, depression is twice as common in girls and women
as in boys and men (Weissman & Klerman, 1977;
McGee et al., 1990; Linehan et al., 1993).
Suicide
In 1996, the age-specific mortality rate from
suicide was 1.6 per 100,000 for 10- to 14-year-olds,
9.5 per 100,000 for 15- to 19-year-olds (i.e., about
six times higher than in the younger age group;
in this age group, boys are about four times as
likely to commit suicide than are girls, while girls
are twice as likely to attempt suicide), compared
with 13.6 per 100,000 for 20- to 24-year-olds (CDC,
1999). Hispanic high school students are more likely
than other students to attempt suicide (CDC, 1998).
There have been some notable changes in these rates
over the past few decades: since the early 1960s,
the reported suicide rate among 15- to 19-year-old
males increased threefold but remained stable among
females in that age group and among 10- to 14-year-olds
(National Center for Health Statistics, 1998); the
rate among white adolescent males reached a peak
in the late 1980s (18.0 per 100,000 in 1986) and
has since declined somewhat (16.0 per 100,000 in
1997), whereas among African American male adolescents,
the rate increased substantially in the same period
(from 7.1 per 100,000 in 1986 to 11.4 per 100,000
in 1997 (CDC, 1998). From 1979 to 1992, the Native
American male adolescent and young adult suicide
rate in Indian Health Service Areas was the highest
in the Nation, with a suicide rate of 62.0 per 100,000
(Wallace et al., 1996).
It has been proposed that the rise in suicidal
behavior among teenage boys results from increased
availability of firearms (Boyd, 1983; Boyd &
Moscicki, 1986; Brent et al., 1987; Brent et al.,
1991) and increased substance abuse in the youth
population (Shaffer et al., 1996c; Birckmayer &
Hemenway, 1999). However, although the rate of suicide
by firearms increased more than suicide by other
methods (Boyd, 1983; Boyd & Moscicki, 1986;
Brent et al., 1987), suicide rates also increased
markedly in many other countries in Europe, in Australia,
and in New Zealand, where suicide by firearms is
rare.
Course and Natural History
Most children with depression experience a recurrence.
Twenty to 40 percent of depressed children relapse
within 2 years, and 70 percent will do so by adulthood
(Garber et al., 1988; Velez et al., 1989; Harrington
et al., 1990; Fleming et al., 1993; Kovacs et al.,
1994; Lewinsohn et al., 1994a; Garrison et al.,
1997). The reasons for relapse are not known, but
there is some evidence that experiencing a depression
leaves behind psychological“scars” that
may increase vulnerability throughout early life
(see below).
The age of first onset of depression appears to
play a role in its course. Children who first become
depressed before puberty are at risk for some form
of mental disorder in adulthood, while teenagers
who first become depressed after puberty are most
likely to experience another episode of depression
(Harrington et al., 1990; McCracken, 1992a; Lewinsohn
et al., 1994a, 1994b; Rao et al., 1995). These differences
in outcome suggest that different mechanisms may
lead to superficially similar but inherently different
clinical conditions. Factors that worsen the prognosis
for depressed children and adolescents include depression
occurring in the context of conduct disorder (Harrington
et al., 1990; Asarnow et al., 1994) and living in
conflict-ridden families (Asarnow et al., 1994).
Children and particularly adolescents who suffer
from depression are at much greater risk of committing
suicide than are children without depression (Shaffer
et al., 1996b).
The prognosis for dysthymia (Klein et al., 1997a)
is unfavorable, with most patients continuing to
feel depressed and to have social difficulties even
after they have apparently recovered. The prognosis
for double depressives (major depressive disorder
plus dysthymia) is worse than that for either condition
alone (Kovacs et al., 1994).
Twenty to 40 percent of adolescents with depression
eventually develop bipolar disorder. Factors that
predict later bipolar disorder include young age
at the time of the first depressive episode, psychotic
features in the initial depression, a family history
of bipolar illness, and symptoms of hypomania developing
during treatment with antidepressant drugs (Garber
et al., 1988; Strober et al., 1993).
Causes
The precise causes of depression are not known.
Extensive research on adults with depression generally
points to both biological and psychosocial factors
(Kendler, 1995). However, there has been substantially
less research on the causes of depression in children
and adolescents. Further discussion of the risk
factors for depression can be found in Chapter 4,
as well as the preceding Overview of Risk Factors
and Prevention section.
Family and Genetic Factors
Much of the research on children and adolescents
with depression has been conducted with those who
attend mental health clinics and with patients who
tend to have the more severe and recurrent forms
of depression, and thus they may not be representative
of all children and adolescents with depression.
With this limitation, research has shown that between
20 and 50 percent of depressed children and adolescents
have a family history of depression (Puig-Antich
et al., 1989; Todd et al., 1993; Williamson et al.,
1995; Kovacs, 1997b). Family research has found
that children of depressed parents are more than
three times as likely as children with nondepressed
parents to experience a depressive disorder (see
Birmaher et al., 1996a, 1996b for a review). They
also are more vulnerable to other mental and somatic
disorders (Downey & Coyne, 1990). Conversely,
estimates of the proportion of depressed parents
who have a depressed child or adolescent vary from
approximately one in six to just under a half (Hammen
et al., 1990). It is not clear whether the relationship
between parent and childhood depression derives
from genetic factors, or whether depressed parents
create an environment that increases the likelihood
of a mental disorder developing in their children
(see below).
Gender Differences
One reason advanced to explain the greater prevalence
of depression in adolescent girls (see above) is
that they are more socially oriented, more dependent
on positive social relationships, and more vulnerable
to losses of social relationships than are boys
(Allgood-Merten et al., 1990). This would increase
their vulnerability to the interpersonal stresses
that are common in teenagers. There is also evidence
that the methods girls use to cope with stress may
entail less denial and more focused and repetitive
thinking about the event (Nolen-Hoeksema & Girgus,
1994). The higher prevalence, therefore, could be
a result of greater vulnerability, combined with
coping mechanisms different than those of boys.
Biological Factors
Some of the core symptoms of depression, such
as changes in appetite and sleep patterns, are related
to the functions of the hypothalamus. The hypothalamus
is, in turn, closely tied to the function of the
pituitary gland. Abnormalities of pituitary function,
such as increased rates of circulating cortisol
and hypo- or hyperthyroidism, are well established
features of depression in adults (Goodwin &
Jamison, 1990). However, far less research has been
done in this area among children and adolescents
(see Birmaher et al., 1996a, 1996b for a review).
It is in the neuroendocrine area that most research
has been done on child and adolescent depression
(see Birmaher et al., 1996a, b). In suicidal adults
dysregulation of the serotonergic system is common
(Mann, 1998; Pine et al., 1995), making them typically
impulsive, intense, and given to extreme reactions.
However, little is known about the association between
abnormal serotonin metabolism and suicidal behavior
in children and adolescents.
Cognitive Factors
For over two decades there has been considerable
interest in the relationship between a particular
“mindset” or approach to perceiving
external events and a predisposition to depression.
The mindset in question is known as a pessimistic“attribution
bias” (Abramson et al., 1978; Beck, 1987;
Hops et al., 1990). A person with this mindset is
one who readily assumes personal blame for negative
events (“All the problems in the family are
my fault”), who expects that one negative
experience is part of a pattern of many other negative
events (“Everything I do is wrong”),
and who believes that a currently negative situation
will endure permanently (“Nothing I do is
going to make anything better”). Such pessimistic
individuals take a characteristically negative view
of positive events (i.e., that they are a result
of someone else’s effort, that they are isolated
events, and that they are unlikely to recur). Individuals
with this mindset react more passively, helplessly,
and ineffectively to negative events than those
without a pessimistic mindset (Seligman, 1975).
There is uncertainty over whether this mindset
precedes depression (and represents a permanent
style of thinking as part of an individual’s
personality), is a manifestation of depression that
is only present when the patient is depressed, and/or
is a consequence or“scar” of a previous,
perhaps unnoticed, depressive episode (Lewinsohn
et al., 1981). This pessimistic mode of thinking
does not occur in children under age 5, which could
be one of the reasons why depression and suicide
are rare in early childhood (Rholes et al., 1980;
Rotenberg, 1982).
There is evidence that children and adolescents
who previously have been depressed may learn, during
their depression, to interpret events in this fashion.
This may make them prone to react similarly to negative
events experienced after recovery, which could be
one of the reasons why previously depressed children
and adolescents are at continuing risk for depression
(Nolen-Hoeksema et al., 1993).
Perceptions of hopelessness, negative views about
one’s own competence, poor self- esteem, a
sense of responsibility for negative events, and
the immutability of these distorted attributions
may contribute to the hopelessness that has been
repeatedly found to be associated with suicidality
(Overholser et al., 1995).
Risk Factors for Suicide and Suicidal
Behavior
There is good evidence that over 90 percent of
children and adolescents who commit suicide have
a mental disorder before their death (Shaffer &
Craft, 1999). The most common disorders that predispose
to suicide are some form of mood disorder, with
or without alcoholism or other substance abuse problem,
and/or certain forms of anxiety disorder (Shaffer
et al., 1996b). Psychological postmortem studies
also show that a significant proportion of suicide
victims suffered from an anxiety disorder at the
time of their death, but the number of victims has
been too small to yield precise odds ratios for
the calculation of an effect. Although the rate
of suicide is greatly increased in schizophrenia,
because of its rarity, it accounts for very few
suicides in the child and adolescent age group.
Controlled studies of completed suicide suggest
similar risk factors for boys and girls (Shafii
et al., 1985; Brent et al., 1988; Groholt et al.,
1997), but with marked differences in their relative
importance (Shaffer et al., 1996c)
Among girls, the most significant risk factor
is the presence of major depression, which, in some
studies, increases the risk of suicide 12-fold.
The next most important risk factor is a previous
suicide attempt, which increases the risk approximately
threefold. Among boys, a previous suicide attempt
is the most potent predictor, increasing the rate
over 30-fold. It is followed by depression (increasing
the rate by about 12-fold), disruptive behavior
(increasing the rate by twofold), and substance
abuse (increasing the rate by just under twofold)
(Shaffer et al., 1996c).
Stressful life events often precede a suicide
and/or suicide attempt (de Wilde et al., 1992; Gould
et al., 1996). As indicated earlier, these stressful
life events include getting into trouble at school
or with a law enforcement agency; a ruptured relationship
with a boyfriend or a girlfriend; or a fight among
friends.7 They are rarely a sufficient cause of
suicide, but they can be precipitating factors in
young people.
Controlled studies (Gould et al., 1996; Hollis,
1996) indicate that low levels of communication
between parents and children may act as a significant
risk factor. While family discord, lack of family
warmth, and disturbed parent-child relationship
are commonly associated with child and adolescent
psychopathology (violent behavior, mood disorder,
alcohol and substance abuse disorders) (Brent et
al., 1994; Pfeffer et al., 1994), these factors
do not play a specific role in suicide (Gould et
al., 1998).
Evidence has accumulated that supports the observation
that suicide can be facilitated in vulnerable teens
by exposure to real or fictional accounts of suicide
(Velting & Gould, 1997), including media coverage
of suicide, such as intensive reporting of the suicide
of a celebrity, or the fictional representation
of a suicide in a popular movie or TV show. The
risk is especially high in the young, and it lasts
for several weeks (Gould & Shaffer, 1986; Phillips
et al., 1989). The suicide of a prominent person
reported on television or in the newspaper or exposure
to some sympathetic fictional representation of
suicide may also tip the balance and make the at-risk
individual feel that suicide is a reasonable, acceptable,
and in some instances even heroic, decision (Gould
& Shaffer, 1986).
The phenomenon of suicide clusters is presumed
to be related to imitation (Davidson, 1989). Suicide
clusters nearly always involve previously disturbed
young people who knew about each other’s death
but rarely knew the other victims personally (Gould,
personal communication, 1999).
Consequences
Both major depressive disorder and dysthymic disorder
are inevitably associated with personal distress,
and if they last a long time or occur repeatedly,
they can lead to a circumscribed life with fewer
friends and sources of support, more stress, and
missed educational and job opportunities (Klein
et al., 1997). The psychological scars of depression
include an enduring pessimistic style of interpreting
events, which may increase the risk of further depressive
episodes. Impairment is greater for those with dysthymic
disorder than for those with major depression (Klein
et al., 1997a), presumably because of the longer
duration of depression in dysthymic disorder, which
is also a prime risk factor for suicide. In a 10-
to 15-year followup study of 73 adolescents diagnosed
with major depression, 7 percent of the adolescents
had committed suicide sometime later. The depressed
adolescents were five times more likely to have
attempted suicide as well, compared with a control
group of age peers without depression (Weissman
et al., 1999).
Treatment
Depression
Psychosocial Interventions
To be deemed effective and approved by the American
Psychological Association, treatments for mental
disorders have to meet very strict criteria. While
interpersonal therapy and systemic family therapy
show promise, they have not been studied sufficiently
to evaluate their effectiveness by these standards.
However, in a comprehensive review article (Kaslow
& Thompson, 1998) that evaluated interventions
for depression in children and adolescents against
the American Psychological Association Task Force
criteria, two forms of cognitive-behavioral therapy
(CBT) were found to be “probably effective
treatments,” although none of the interventions
for depression were deemed, as yet, to meet the
Association’s higher standard for a well-established
intervention.
In studies that focused on relieving symptoms
of depression in preadolescents, only one form of
CBT met the criteria for a probably effective intervention.
In the first study, the relative efficacy of two
types of CBT—12-session group interventions
based on either self-control therapy or behavior-solving
therapy—were compared with a“waiting
list” control group (Stark et al., 1987).
Children responded to both CBT interventions with
fewer symptoms of depression and anxiety, whereas
the waiting list group exhibited minimal change.
Because improvement was greatest with self-control
therapy, this intervention was compared in a later
study with a traditional counseling condition. Self-control
therapy, enhanced by doubling the number of sessions,
entailed social skills training, assertiveness training,
relaxation training and imagery, and cognitive restructuring.
Monthly family meetings were also added to both
the experimental and control conditions. Children
receiving self-control therapy reported fewer symptoms
at 7-month followup (Stark et al., 1991).
Among the numerous studies of adolescents reviewed
by Kaslow and Thomson (1998), one form of CBT—coping
skills—was judged probably efficacious. This
intervention, based on the “Coping with Depression”
course, was developed originally in Oregon for adults
by Lewinsohn and colleagues (Lewinsohn et al., 1996)
and adapted by Clarke and colleagues (1992) for
school-based programs to treat adolescent depression.
Compared with controls on the waiting list, adolescents
who received CBT had lower rates of depression,
less self-reported depression, improvement in cognitions,
and increased activity levels (Lewinsohn et al.,
1990, 1996). To achieve well-established status,
as defined by the American Psychological Association
Task Force, the intervention has to be studied by
another team of investigators—which has not
as yet been done.
Pharmacological Treatment
Prior to 1996, the medications of choice for major
depression in children and adolescents were the
tricyclic antidepressants, a choice based on numerous
studies in adults. However, 13 distinct trials in
children and adolescents failed to demonstrate the
efficacy of tricyclic antidepressants for younger
ages. Tricyclic antidepressants also have a higher
risk of toxicity than selective serotonin reuptake
inhibitors (SSRIs) (Walsh et al., 1994; Kutcher,
1998). The current consensus is that tricyclic medications
are not the medication of choice for depressed children
and adolescents (Eisenberg, 1996; Fisher & Fisher,
1996).
Recent research indicates that young people with
depressive disorders may respond more favorably
to SSRIs than to tricyclic antidepressants. The
first SSRI tested in children and adolescents was
fluoxetine. In a study of 96 outpatients over 8
weeks, 56 percent receiving fluoxetine and 33 percent
receiving placebo were “much” or“very
much” improved on the Clinical Global Improvement
Scale. Benefits were comparable across age groups.
Complete symptom remission occurred for 31 percent
of fluoxetine-treated patients compared with 23
percent of placebo-treated patients (Emslie et al.,
1997). A recent open trial of fluoxetine for adolescents
hospitalized for treatment of major depression found
it to decrease depression scores more effectively
than imipramine, a tricyclic antidepressant (Strober
et al., 1999), with the further advantage that fluoxetine
was well tolerated.
The safety of a second SSRI, paroxetine, was demonstrated
in a multicenter double-blind placebo-controlled
trial. Paroxetine was compared with imipramine and
placebo in 275 adolescents who met the DSM-IV criteria
for major depression. Preliminary results indicate
that, mostly because of side effects, one-third
of imipramine patients withdrew from the study,
a proportion significantly higher than that for
paroxetine (10 percent) and placebo (7 percent)
(Wagner et al., 1998). One of the co-investigators
of this study noted that paroxetine’s efficacy
was superior to that of imipramine and placebo on
the Clinical Global Improvement Scale (Graham Emslie,
personal communication, October 1998). However,
final conclusions about the benefit of this second
SSRI must await publication of the outcomes of this
multicenter study.
In summary, psychosocial interventions for depressed
children and adolescents indicate great promise,
with several types of cognitive-behavioral therapy
for the child or adolescent leading the way. With
respect to pharmacotherapy, new studies attest to
the safety and efficacy of two SSRIs. These promising
findings are being extended in the recently begun
NIMH-funded Treatment of Adolescents with Depression
study.
Bipolar Disorder
Pharmacological Treatment
The treatment of bipolar disorder entails treating
symptoms of both depression and mania. For decades,
lithium has been the well-researched mainstay treatment
for mania in adults. Mania in bipolar disorder of
children is also treated with lithium, although
the relevant research on children lags behind that
on adults. Only in recent years have researchers
begun to study lithium in children and adolescents,
with good clinical response. Open trials of lithium
were conducted in the late 1980s (Varanka et al.,
1988; Strober et al., 1990). More recently, lithium
proved to be more effective than placebo in treating
adolescents who were bipolar and substance dependent
(Geller et al., 1998).
Children experience the same safety problems with
lithium as do adults: toxicity and impairment of
renal and thyroid functioning (Geller & Luby,
1997). Lithium is therefore not recommended for
families unable to keep regular appointments that
would ensure monitoring of serum lithium levels
and of adverse events. Patients who discontinue
taking the drug have a high relapse rate (Strober
et al., 1990).
As yet, there are no controlled studies on a number
of other psychotropic agents also used clinically
in children and adolescents with bipolar disorder,
including valproate, carbamazepine, methylphenidate,
and low-dose chlorpromazine (Campbell & Cueva,
1995; Geller & Luby, 1997).
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