Pediatric bipolar disorder: Mood swings, irritability are cues to this diagnosis
Our challenge is to make the diagnosis early and stabilize mood so that these young patients can cope and achieve at home and in school.
Children and adolescents with bipolar disorder are often referred to psychiatrists because of disruptive behaviors at home and in school. They exhibit poor academic performance, disturbed interpersonal relationships, increased rates of substance abuse, legal difficulties, multiple hospitalizations, and high rates of suicide attempts and completions. 1,2 Many have comorbid psychiatric problems—particularly attention-deficit/hyperactivity disorder (ADHD).
Although few studies have examined this complex diagnosis, we do know that bipolar disorder presents differently in children and adolescents than in adults. Prodromal symptoms can appear early—before kindergarten in some children. Early recognition therefore is key to effectively treating these sick and often complicated patients.
How often a clinician encounters a child or adolescent with bipolar disorder depends largely on the practice setting (Box). 1,3,4 Wherever you practice, however, you can recognize and treat pediatric bipolar disorder if you keep in mind that its presentation and disease progression differ from the adult type.
Pediatric versus adult symptoms
Prodromal symptoms—such as episodes of depressed mood or hopelessness and excessive mood lability—have been detected in youths who later were diagnosed with bipolar disorder. More than one-half of 494 adult members of the Depression and Bipolar Support Alliance have reported that they first exhibited signs of bipolar illness before age 19, with distribution by age as follows:
- 5% before age 5
- 12% at ages 5 to 9
- 14% at ages 10 to 14
- 28% at ages 15 to 19. 5
HOW LIKELY ARE YOU TO SEE PEDIATRIC BIPOLAR DISORDER?
Pediatric bipolar disorder is seen much more commonly in specialized psychiatric settings than in general practice.
Overall prevalence. A large, well-designed population study of mood disorders in adolescents reported a lifetime prevalence of 1% for bipolar spectrum disorders, including bipolar I, bipolar II, and cyclothymia. 1 Most adolescents in the bipolar group (84%) reported a distinct period of elevated, expansive, or irritable mood that best fit DSM-IV criteria for bipolar disorder not otherwise specified (NOS). These adolescents—who represented an overall prevalence of 5.7%—had extremely high rates of psychosocial impairment and use of mental health services, similar to those with bipolar I disorder.
In specialized settings. Bipolar disorder is seen much more frequently in specialized settings, such as a pediatric psychopharmacology clinic, than in general psychiatric practice. For example:
- Among 262 children referred consecutively to a specialty pediatric psychopharmacology clinic, 16% met DSM-III-R criteria for mania. 3
- In a special education class, 8 of 12 students met DSM-III-R criteria for a bipolar disorder. 4
- In child and adolescent psychiatry inpatient units, it is not uncommon to find 30 to 40% of patients with a bipolar disorder.
COMMON PRESENTING SYMPTOMS OF PEDIATRIC BIPOLAR DISORDER
Episodes of depressed mood/hopelessness
Excessive mood lability
Periods of increased or decreased energy
Episodes of decreased need for sleep
Markedly irritable moods
In a similar study, 6 58 adult patients with bipolar I disorder reported an average interval of 9 to 12 years between the emergence of bipolar symptoms and the onset of a major affective disorder.
Common initial symptoms of pediatric bipolar disorder are listed in Table 1. Most of these symptoms occur in discrete episodes and represent a change from the child’s normal functioning.
Many children and adolescents are labeled “bipolar” without careful consideration of this disorder’s diagnostic complexities and subtypes. Bipolarity in young patients can be difficult to establish because of:
- variability of symptom expression, depending on the illness’ context and phase
- effects of development on symptom expression
- mood and behavioral effects of psychotropic medications the patient is taking.
Pediatric bipolar patients often present with a mixed or “dysphoric” picture characterized by frequent short periods of intense mood lability and irritability rather than classic euphoric mania. 3,7 Clinicians who evaluate children with pediatric bipolar disorders often try to fit them into the DSM-IV “rapid cycling” subtype. This subtype does not fit bipolar children very well, however, because they often lack clear episodes of mania. Rather, researchers are reporting that bipolar children cycle far more frequently than the four episodes/year in DSM-IV’s diagnostic criteria:
- Continuous, daily cycling from mania or hypomania to euthymia or depression was seen in 81% of a well-defined group of pediatric bipolar patients. 7,8
- A high rate of rapid cycling and onset of a first manic episode at mean age 7 was reported in 90 children and adolescents (mean age 11) with bipolar I disorder. 9
Making the diagnosis
DSM-IV’s diagnostic classification system for bipolar disorders is complex, involving:
- five types of episodes (manic, hypomanic, mixed, depressed, unspecified)
- four severity levels (mild, moderate, severe without psychosis, severe with psychosis)
- and three course specifiers (with or without inter-episode recovery, seasonal pattern, rapid cycling).
PEDIATRIC BIPOLAR DISORDER SUBTYPES: DIAGNOSTIC CHARACTERISTICS AND ASSOCIATED FEATURES
Minimum duration of manic symptoms
Pure mixed or manic
Major depressive disorder presentation of bipolar may be the first disorder, particularly in adolescents
Multiple daily mood swings with severe irritability (mood lability)
One or more prior episodes of major depressive disorder required, each with a duration of 2 weeks
Noticeable manic symptoms that do not cause significant dysfunction or lead to hospitalization
Hypomania cycling with depressive symptoms
Hypomania cycling with depressive symptoms, without manic, mixed, or major depressive episodes (1 year, with symptom-free intervals <2 months)
Chronic, low-level mood cycling
< 4 days of bipolar symptoms
Rapid alternation (within days) between manic depressive symptoms without full manic, mixed, or major depressive episodes
May include hypomanic and episodes (but <4 days) without intercurrent depression
NOS: not otherwise specified
COMPLICATING FACTORS IN PEDIATRIC BIPOLAR DISORDER
Medical conditions that may mimic bipolar mania
Temporal lobe epilepsy
Closed or open head injury
Systemic lupus erythematosus
Alcohol-related neurodevelopmental disorder
Wilson’s disease (rare progressive disease caused by defective copper metabolism)
Medications that may increase mood cycling
Selective serotonin reuptake inhibitors
Serotonin and norepinephrine reuptake inhibitors
Sympathomimetic amines, such as pseudoephedrine
DSM-IV criteria for mania—which were developed from data on adults with bipolar disorders—do not take into account developmental differences between bipolar adults and bipolar children and adolescents.
Diagnostic characteristics of the pediatric bipolar disorder subtypes are compared in Table 2. Generally:
- Pediatric patients with bipolar I disorder have multiple daily mood swings, a “mixed” type of episode with short periods of euphoria and longer periods of irritability, and comorbidities such as ADHD, oppositional defiant disorder, or conduct disorder. 3,11,12
- Bipolar II disorder presents more typically in adolescence and is usually noticed clinically as a major depressive episode. Past episodes of hypomania may have been missed unless a careful history was taken.
- Cyclothymia is difficult to diagnose because the hypomania and depressive symptoms are not as severe as in bipolar types I or II. Prospective mood charting can help the clinician diagnose cyclothymia (see “Related Resources”).
- Bipolar disorder NOS represents the largest group of patients with bipolar symptoms. This diagnosis is made when bipolar symptoms are present but not of sufficient severity or duration to warrant a diagnosis of bipolar I, II or cyclothymia. Bipolar NOS also can be diagnosed when a bipolar disorder is secondary to a general medical condition, such as fetal alcohol syndrome or alcohol-related neurodevelopmental disorder.
Differential diagnosis. Medications and medical disorders may exacerbate or mimic pediatric bipolar symptoms (Table 3), so it is important to assess these potential confounds before initiating treatment. Psychiatric comorbidities also frequently complicate the presentation of pediatric bipolar disorder and its response to treatment (Table 4). ADHD is the most common comorbidity, with rates as high as 98% in bipolar children. 3,13
Long-term outcomes of children and adolescents with bipolar disorders have not been well studied. In the only prospective follow-up investigation of adolescent inpatients with mania, Strober et al found that most of 54 patients (96%) recovered from an index affective episode, but nearly one-half (44%) experienced one or more relapses within 5 years. 14 The rate of recovery varied according to the index episode’s polarity. Recovery was faster in patients with pure mania or mixed states, and multiple relapses occurred more frequently in those with mixed or cycling episodes. Twenty percent of the patients attempted suicide.
Recently, Geller et al reported the results of the first large, prospective, follow-up study of children with bipolar disorder. 15 In 89 outpatients (mean age 11) with bipolar I disorder, comprehensive assessments at baseline and at 6, 12, 18, and 24 months showed that 65% recovered from mania but 55% relapsed after recovery. Mean time to recovery was 36 weeks, and relapse occurred after a mean of 28.6 weeks. Children living with their intact biological families were twice as likely to recover as those in other living arrangements.
The poor outcomes of these bipolar children highlight the need for earlier recognition and more effective treatments.
Treating acute mania
Many psychotropic medications used to treat adults with bipolar disorders are also used for children and adolescents. To date, only two double-blind, placebo-controlled studies 13,16 and one uncontrolled maintenance treatment study 17 have examined treatment of acute mania in pediatric bipolar disorder.
Lithium is the most studied medication for pediatric bipolar disorder and the only FDA-approved medication for treating acute mania and bipolar disorder in patients ages 12 to 18. Approximately 40 to 50% of children and adolescents with bipolar disorder respond to lithium monotherapy. 18,19
In general, lithium should be titrated to 30 mg/kg/d in two or three divided doses; this typically produces a serum level of 0.8 to 1.2 mEq/L. Common side effects in children and adolescents include nausea, polyuria, polydipsia, tremor, acne, and weight gain. Lithium levels and thyroid function should be monitored, as in adult patients.
Only one prospective, placebo-controlled study has examined lithium use in children and adolescents with bipolar disorders. Twenty-five adolescents with comorbid bipolar and substance use disorders were treated with lithium or placebo for 6 weeks. Positive urine toxicology screens decreased significantly, and global assessment of functioning improved in 46% of those receiving lithium vs. 8% of those receiving placebo. 13 This study demonstrated lithium’s efficacy in treating bipolar adolescents with comorbid substance abuse but did not measure its effect on mood.
Risk factors for poor lithium response in children and adolescents with bipolar disorder include prepubertal onset and comorbid ADHD. 20
Divalproex. No placebo-controlled studies of antiepileptics in pediatric bipolar disorder have been published. Open-label studies of divalproex have reported response rates of 53 to 82% in manic adolescents. 18, 21-23 Several case reports and series have described successful use of carbamazepine as monotherapy and adjunctive treatment in children and adolescents with bipolar disorder. 24,25
RATES OF COMMON COMORBIDITIES IN PEDIATRIC BIPOLAR DISORDERS
70 to 90%
30 to 60%
20 to 30%
30 to 40%
20 to 30%
30 to 50%
Oppositional defiant disorder
60 to 80%
20 to 30%
40 to 80%
30 to 40%
30 to 40%
One 6-week, random-assignment, prospective study compared lithium, divalproex, and carbamazepine in treating 42 acutely manic or hypomanic patients ages 8 to 18. 18 In this open study, all three mood stabilizers demonstrated efficacy in treating a mixed or manic episode in youths with bipolar I or II disorder. Response rates—based on a 50% improvement in Young Mania Rating Scale baseline scores—were divalproex 53%, lithium 38%, and carbamazepine 38%.