Pediatric bipolar disorder: Assessment and diagnosis

INTRODUCTION — 

Bipolar disorder in children and adolescents is characterized by mood-elevated syndromes (eg, mania or hypomania) that are episodic, exceed what is expected for the child’s developmental stage, and are not better explained by other psychiatric and medical conditions [1-4]. In addition, youth with the disorder usually have recurrent episodes of depression (eg, major depression); however, depressive syndromes are not required for diagnosing bipolar disorder.

Pediatric bipolar disorder can severely disrupt normal development and psychosocial functioning, and increases the risk for suicide, psychosis, and comorbidities (eg, substance use disorder and obesity), as well as behavioral, academic, and legal problems [4-8]. Patients with bipolar disorder frequently have a variable course with rapid fluctuation in mood symptoms during acute episodes, and frequently present with mixed features. These factors, coupled with developmental problems and difficulties that youth can have verbalizing their emotions and symptoms, contribute to the complexity and controversies in diagnosing children and adolescents with bipolar disorder.

In up to 60 percent of adults with bipolar disorder, onset of mood symptoms occurs before age 20 [4,9,10]. However, pediatric bipolar disorder is often not recognized, and many youth with the disorder do not receive treatment or are treated for comorbid conditions rather than bipolar disorder [11]. In two retrospective studies of pediatric bipolar disorder, the lag time from onset of the first mood-elevated syndrome to first mental health contact or community diagnosis was nearly two years [12,13].

This topic describes the assessment and diagnosis of bipolar disorder in children and adolescents. The epidemiology, clinical presentation, comorbidity, and treatment of pediatric bipolar disorder are discussed separately.

●(See "Pediatric bipolar disorder: Epidemiology and pathogenesis".)

●(See "Pediatric bipolar disorder: Clinical manifestations and course of illness".)

●(See "Pediatric bipolar disorder: Comorbidity".)

●(See "Pediatric bipolar disorder: Overview of choosing treatment".)

●(See "Pediatric bipolar major depression: Choosing treatment".)

●(See "Pediatric bipolar disorder and pharmacotherapy: General principles".)

●(See "Pediatric mania and second-generation antipsychotics: Efficacy, administration, and side effects".)

●(See "Pediatric bipolar disorder: Efficacy and core elements of adjunctive psychotherapy".)

WHEN TO SUSPECT THE DISORDER — 

Pediatricians and other primary care clinicians should be alert to symptoms, particularly if they are concurrent and episodic, which suggest the possibility of pediatric bipolar disorder:

●Increased activity and/or silliness with intermittent euthymic periods that are above and beyond what is expected for the developmental age of the child and not accounted for by the situation, other psychiatric disorders, or medications.

●Decreased need for sleep for several nights, such that the child is not tired or sleepy the day after having slept only slept a few hours (eg, three to four) or not at all.

●Hypersexuality and inappropriate sexual behaviors that are out of character, not expected for the mental/chronologic age of the child/adolescent, and occur without a history of exposure to sexual activity (eg, abuse or videos).

●Depression in patients with:

•Psychotic features (delusions and/or hallucinations) – Prospective observational studies indicate that in depressed patients, psychotic symptoms are a strong predictor of bipolar disorder, particularly if there is family history of bipolar disorder [14].

•A family history of bipolar disorder – Youth with depression and a positive family history of bipolar disorder are at increased risk of eventually developing mania/hypomania, especially if bipolar disorder occurred in a parent, and onset in the parent was early in life (eg, before age 25) [14,15].

•Subthreshold mania – Mild or transient manic symptoms that do not meet the diagnostic threshold for episodes of mania or hypomania may occur in depressed patients and can be a harbinger of eventual mania [3,4,14].

ASSESSMENT

General approach — Unless a primary care clinician has experience with pediatric bipolar disorder, patients in whom the disorder is strongly suspected should be evaluated by a child psychiatrist or other mental health specialist skilled in identifying the disorder. Diagnosing bipolar disorder in children and adolescents can be complex, and many symptomatic patients face delays in receiving the diagnosis.

Assessment of manic, hypomanic, and depressive symptoms in youth requires careful probing. In addition, it is important to ascertain the frequency, intensity, number, and duration (summarized by the acronym “FIND”) of manic, hypomanic, and depressive mood episodes [16], as well as episodes with mixed features (ie, mood episodes that are accompanied by symptoms of the opposite polarity) [1]. Multiple interviews may be required to make the diagnosis.

Given that lack of insight can be associated with mania or hypomania, it is imperative to obtain information from caregivers or other adults (eg, teachers) who know the child well to accurately assess symptoms and potential change in functioning. The child’s chronologic age, intellectual capabilities, and environment need to be taken into account when assessing the level of functional impairment.

Specific elements — The assessment for bipolar disorder includes the following elements:

●History of present illness

•Symptoms of mania, hypomania, and major depression

•Suicidal ideation and behavior

•Homicidal symptoms

•Psychotic features (eg, delusions and hallucinations)

•Comorbid psychiatric disorders, including:

-Anxiety disorders

-Attention deficit hyperactivity disorder (ADHD)

-Autism spectrum disorder

-Substance use disorder

•Other medical disorders such as obesity

•Psychosocial functioning

•Treatment

●Past psychiatric history (especially bipolar disorder)

●Family psychiatric history

●Social history, including family environment and ongoing negative life events (eg, family conflicts and abuse)

●Mental status examination

Using school years, birthdays, and holidays as anchor points, timelines can be established to help assess the onset and course of mood disorders.

In some cases, psychometric testing can be useful for children with learning problems or suspected intellectual disability. (See "Specific learning disorders in children: Evaluation", section on 'Psychometric tests'.)

Assessment instruments — Assessment of mood and other psychiatric symptoms can be facilitated by using the structured and semistructured interviews and rating scales described below. The structured interviews can generate a diagnosis, whereas the rating scales do not. However, the rating scales reveal symptoms that may alert clinicians to further assess for bipolar disorder. The rating scales can also be used during treatment to monitor the severity of symptoms over time.

Structured diagnostic interviews — There are several structured and semistructured interviews that can be used for diagnosing bipolar disorder, including the Kiddie Schedule for Affective Disorders and Schizophrenia for school age children - Present and Lifetime version (KSADS-PL) [17], Mini International Neuropsychiatric Interview for Children and Adolescents (MINI-KID) [18], and the National Institute of Mental Health Diagnostic Interview Schedule for Children Version IV (NIMH DISC-IV) [19]. However, these interviews are reserved for research because they are lengthy and time-consuming.

Rating scales — Rating scales that can be used to assess youth for bipolar disorder include the following:

●Clinician-administered scales – Clinician-administered rating scales that assess manic symptoms and their severity in youth include the Young Mania Rating Scale (YMRS) [20], as well as the KSADS Mania Rating Scale (KMRS) that is derived from the KSADS-P mania module [20,21]. However, using these scales requires training.

●Youth-, parent-, and teacher-administered scales – It appears that parental reports are more effective in identifying mania than youth or teacher reports [20]. The General Behavior Inventory [20], the parent version of the YMRS (P-YMRS) [20], and the Child Mania Rating Scale for Parents (about their children) [20,22] are each psychometrically sound and can be used to screen for bipolar disorder symptoms in youth. However, caution is needed because these self-report scales usually do not properly elicit the clustering and periodicity of manic/hypomanic symptoms. In addition, the symptoms included in these scales can overlap with symptoms of other disorders (eg, ADHD).

The Child Behavior Checklist (CBCL) is a parent-report instrument that has been used to screen for bipolar disorder in youths by summing the Attention, Aggression, and Anxious/Depressed subscales (CBCL-PBD; pediatric bipolar disorder phenotype) [20]. However, the CBCL-PBD is not specific for assessing mania; rather, it seems to detect mood lability or severe psychopathology [23].

●Daily mood scales – Daily mood scales, also called mood diaries, are patient self-report scales that can help assess the course of a patient’s mood symptoms over time. As an example, the following graphic provides a self-report form that consists of a simple scatter line in which 0 represents feeling very sad, 10 excessively happy and 5 is a normal mood (form 1). The graphic also asks about factors that may help explain the mood rating, such as stressors and use of medications. Multiple smartphone applications are available for tracking mood fluctuations. We suggest that the patient tries more than one daily mood scale or smartphone application to find the one that the youth likes the most and finds easy to use.

DIAGNOSIS — 

Accurate diagnosis of bipolar disorder in children and adolescents is critically important. A misdiagnosis of bipolar disorder may have lifelong implications for youth and expose them to medications with risk of serious side effects and little benefit. Conversely, failing to identify bipolar disorder leaves patients with an untreated illness that can affect their normal development. Variability in the clinical presentation of bipolar disorder can make diagnosis difficult. The diagnosis may also be obscured by the presence of comorbidities and overlapping symptoms with other psychiatric disorders. (See "Pediatric bipolar disorder: Clinical manifestations and course of illness", section on 'Clinical presentation' and 'Differential diagnosis' below.)

Overview — Diagnosis of bipolar disorder and its subtypes begins by diagnosing the manic or hypomanic episodes that determine the diagnosis of this disorder. It is crucial to ascertain whether the symptoms present in clusters above and beyond any other comorbid psychopathology, and whether the manic/hypomanic syndromes are episodic. In addition, the diagnosis requires that clinicians exclude other relevant psychiatric and other medical conditions that can manifest with symptoms that overlap with those of bipolar disorder. (See 'Mood episodes' below and 'Bipolar disorders' below and 'Differential diagnosis' below.)

We suggest diagnosing bipolar mood episodes and disorders according to the criteria in the American Psychiatric Association’s Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, Text Revision (DSM-5-TR) [3]. Although the diagnostic criteria were not developed or specifically adapted for use in pediatric populations, it is possible to apply the criteria to children and adolescents by accounting for developmental issues.

A reasonable alternative to DSM-5-TR is the World Health Organization’s International Classification of Diseases-11^th Revision (ICD-11) [24]. The two sets of criteria are largely the same.

Diagnostic challenges — The challenges in diagnosing pediatric bipolar disorder underscore the need for comprehensive cross-sectional and longitudinal assessments by clinicians well trained to make this diagnosis.

The diagnosis of bipolar disorder in youth can be complex because youth with the disorder frequently have a variable course with rapid fluctuation in mood symptoms during acute episodes, developmental issues that complicate the assessment of symptoms and behaviors, and difficulty verbalizing their emotions and symptoms. The social context in which the disorder arises (eg, the presence of family conflicts), and the effects of existing medications on the child’s mood, may pose further difficulties in making the diagnosis.

In addition, bipolar disorder overlaps with other psychiatric disorders [25]. As an example, mania with psychotic features may resemble schizophrenia, and irritability can occur in either mania or attention deficit hyperactivity disorder (ADHD). Diagnosing bipolar disorder is also complicated by comorbidities such as anxiety disorders, ADHD, and substance use disorders. (See 'Differential diagnosis' below and "Pediatric bipolar disorder: Comorbidity".)

Another diagnostic challenge involves the dimensional nature of bipolar symptoms and disorders, which occur along a continuum of severity ranging from mild to severe [4,25]. As an example, mania and hypomania each represent mood-elevated syndromes. The differences between the two may be subtle, because they are distinguished in part by the severity of symptoms that are common to both. (See 'Mania' below and 'Hypomania' below.)

Mood episodes — Bipolar mood episodes include mania, hypomania, and major depression; however, episodes of major depression are not necessary to make the diagnosis of bipolar disorder [3]. The distinction between the symptoms of these episodes and normal behavior in children is discussed in detail separately. (See "Pediatric bipolar disorder: Clinical manifestations and course of illness", section on 'Clinical presentation'.)

Mania — Mania is an episodic syndrome of concurrent symptoms and behaviors. The diagnostic criteria for manic episodes according to DSM-5-TR are described in the table (table 1).

The core symptoms of mania are abnormally and persistently [3]:

●Elevated, expansive, and/or irritable mood

●Increased energy or goal directed activity

To diagnose mania, both of these symptoms need to occur for at least one week (or any duration if hospitalization is necessary), nearly every day, for most of the day. During this period of mood disturbance and increased energy or activity, at least three (if elated mood predominates) or four (if irritable mood predominates) of the following symptoms must also be present [3]:

●Inflated self-esteem or grandiosity

●Decreased need for sleep (eg, feels rested after three or four hours of sleep)

●More talkative than usual or pressured speech

●Racing thoughts or flight of ideas (abrupt changes from one topic to another that are based upon understandable associations)

●Distractibility

●Increase in goal-directed activity or psychomotor agitation

●Excessive involvement in pleasurable activities that have a high potential for painful consequences (eg, buying sprees or sexual indiscretions)

A meta-analysis of 20 observational studies evaluated the frequency of these manic symptoms in youth with bipolar I disorder and other specified bipolar disorder (total n >2000) [26]. The most common symptoms included increased energy, irritability, mood lability, distractibility, and goal directed activity (each occurred in approximately 75 percent of patients) (table 2). However, heterogeneity across studies in the rates of most symptoms was substantial, due to differences in the methods (eg, studies varied in how they diagnosed bipolar disorder).

Another diagnostic criterion for mania is that the syndrome includes or leads to at least one of the following: markedly impaired psychosocial functioning, psychotic features (eg, delusions or hallucinations), or inpatient hospitalization to prevent harming oneself or others [3].

Mania is not diagnosed if the mood-elevated symptoms are attributable to a substance (eg, cannabis, cocaine, or hallucinogen), medication (eg, antidepressant or stimulant), or another medical disorder (eg, hyperthyroidism) [3]. However, if mania arises during treatment with an antidepressant medication or neuromodulation (eg, electroconvulsive therapy), and the full syndrome persists beyond the physiologic effect of that treatment, the syndrome is classified as a manic episode.

The diagnosis of mania leads to a diagnosis of bipolar I disorder. (See 'Bipolar I disorder' below.)

Hypomania — Hypomania is an episodic syndrome of concurrent symptoms and behaviors. The DSM-5-TR diagnostic criteria for hypomanic episodes are described in the table (table 3). Hypomania is characterized by an abnormally and persistently elevated or irritable mood, as well as increased energy or goal directed activity [3]. The symptoms last at least four consecutive days, for most of the day, nearly every day. During this period, at least three (if elated mood predominates) or four (if irritable mood predominates) of the following symptoms must also be present:

●Inflated self-esteem or grandiosity

●Decreased need for sleep (eg, feels rested after three or four hours of sleep)

●More talkative than usual or pressured speech

●Racing thoughts or flight of ideas (abrupt changes from one topic to another that are based upon understandable associations)

●Distractibility

●Increase in goal-directed activity or psychomotor agitation

●Excessive involvement in pleasurable activities that have a high potential for painful consequences (eg, buying sprees or sexual indiscretions)

The distinction between hypomanic and manic episodes in DSM-5-TR is based upon the following criteria [3]:

●Duration of symptoms – The diagnosis of hypomania requires at least four days of symptoms, whereas mania requires at least seven days.

●Intensity of symptoms – Hypomanic symptoms are less severe than manic symptoms. As an example, in a patient with average academic abilities who develops hypomania, inflated self-esteem may include thoughts that the patient is the best student in the class, whereas mania may include the belief that one is the best student in the country.

Mania may be so severe that patients manifest psychotic features such as delusions, which are usually mood congruent (eg, believing that one has superpowers or is the messiah). Hypomania never includes psychotic features.

●Psychosocial functioning – Psychosocial functioning in hypomania is either mildly impaired or significantly improved, whereas functioning in mania is markedly impaired.

●Hospitalization – Hypomania never requires inpatient hospitalization, whereas mania may necessitate hospitalization to prevent harming oneself or others.

Hypomania is not diagnosed if the mood-elevated symptoms are attributable to a substance (eg, cannabis, cocaine, or hallucinogen), medication (eg, antidepressant or stimulant), or another medical disorder (eg, hyperthyroidism) [3]. However, if hypomania arises during treatment with an antidepressant medication or neuromodulation (eg, electroconvulsive therapy), and the full syndrome persists beyond the physiologic effect of that treatment, the syndrome is classified as a hypomanic episode.

Hypomania may be difficult to diagnose because in some cases, functioning (eg, academic and social) can improve during the episode. In addition, the difference between symptoms and normal mood/behaviors can be subtle.

Hypomanic episodes may occur with bipolar I disorder, bipolar II disorder, or other specified bipolar and related disorder. (See 'Bipolar disorders' below.)

Major depression — Major depression is an episodic syndrome of concurrent symptoms and behaviors. Pediatric bipolar disorder usually includes episodes of major depression, but they are not necessary for the diagnosis of bipolar disorder. The DSM-5-TR diagnostic criteria for major depressive episodes are described in the table (table 4). Major depression is characterized by at least five of the following symptoms for at least two weeks; at least one of the symptoms is dysphoria, irritability, or anhedonia [3]:

●Depressed mood (dysphoria) or irritability most of the day, nearly every day

●Diminished interest or pleasure (anhedonia) in nearly all daily activities, most of the day, nearly every day

●Significant weight loss or weight gain (eg, 5 percent within a month)

●Insomnia or hypersomnia nearly every day

●Psychomotor agitation or retardation nearly every day

●Fatigue or loss of energy nearly every day

●Thoughts of worthlessness or inappropriate guilt nearly every day

●Diminished ability to think or concentrate nearly every day

●Recurrent thoughts of death or suicidal ideation, or a suicide attempt

In addition, the symptoms cause significant distress or psychosocial impairment. Although controversial, in DSM-5-TR, bereavement does not exclude the diagnosis of a major depressive episode. Major depressive episodes may occur with bipolar I disorder, bipolar II disorder, or other specified bipolar disorder. (See 'Bipolar disorders' below.)

Depressive symptoms may fluctuate more frequently in depressed children compared with adults, and depressed children may be more reactive than depressed adults. Depressed children may not look or feel depressed; instead, they may be irritable. They can be depressed in one setting (eg, at school), but look or feel happy when they are with their friends or playing games.

Major depression is not diagnosed if the depressive symptoms are attributable to a substance (eg, opiate), medication (eg, glucocorticoids), or another medical disorder (eg, hypothyroidism) [3].

Additional information about the clinical features and diagnosis of depression is discussed separately. (See "Approach to the adult patient with suspected depression".)

Mood episode specifiers — DSM-5-TR uses several terms to increase the diagnostic specificity of bipolar mood episodes, including [3]:

●Psychotic features – Psychotic features include delusions (false, fixed beliefs), hallucinations (false sensory perceptions), and thought disorder (disorganized cognition and illogical thoughts), any of which can occur at any time during a mood episode (see "Psychosis in adults: Epidemiology, clinical manifestations, and diagnostic evaluation", section on 'Clinical manifestations')

●Catatonia – Catatonic features are characterized by prominent psychomotor disturbances that occur during most of the episode (see "Catatonia in adults: Epidemiology, clinical features, assessment, and diagnosis")

●Anxious distress – Anxious distress is characterized by the presence of two or more of the following symptoms during most days of the mood episode:

•Tension

•Restless

•Impaired concentration due to worry

•Fear that something awful may happen

•Fear of losing self-control

●Mixed features – Episodes of mania, hypomania, and major depression can be accompanied by symptoms of the opposite polarity and are referred to as mood episodes with mixed features (eg, major depression with mixed features):

•Manic or hypomanic episodes with mixed features are characterized by episodes that meet full criteria for mania (table 1) or hypomania (table 3), and at least three of the following symptoms during most days of the episode: depressed mood, diminished interest or pleasure in most activities, psychomotor retardation, low energy, excessive guilt or thoughts of worthlessness, and recurrent thoughts of death.

•Major depressive episodes with mixed features are characterized by episodes that meet full criteria for major depression (table 4), and at least three of the following symptoms during most days of the episode: elevated or expansive mood, inflated self-esteem or grandiosity, more talkative than usual or pressured speech, flight of ideas (abrupt changes from one topic to another that are based upon understandable associations) or racing thoughts, increased energy or goal-directed activity, excessive involvement in pleasurable activities that have a high potential for painful consequences (eg, buying sprees or sexual indiscretions), and decreased need for sleep.

●Melancholic features – Melancholic features are characterized by at least four of the following symptoms during an episode of major depression; at least one of the symptoms is either loss of pleasure or lack of reactivity to pleasurable stimuli:

•Loss of pleasure in most activities

•Unreactive to usually pleasurable stimuli (ie, does not feel better in response to positive events)

•Depressed mood marked by despondency, despair, or remorse

•Early morning awakening (eg, two hours before usual hours of awakening)

•Psychomotor retardation or agitation

•Anorexia or weight loss

•Excessive guilt

●Atypical features – Atypical features are characterized by at least three of the following symptoms during an episode of major depression; at least one of the symptoms is mood reactivity to pleasurable stimuli:

•Reactive to pleasurable stimuli (ie, feels better in response to positive events)

•Increased appetite or weight gain

•Hypersomnia (eg, sleeping at least 10 hours per day, or at least 2 hours more than usual when not depressed)

•Heavy or leaden feelings in limbs

•Longstanding pattern of interpersonal rejection sensitivity (ie, feeling deep anxiety, humiliation, or anger at the slightest rebuff from others) that is not limited to mood episodes, and which causes social or occupational conflicts

●Peripartum onset – Peripartum onset refers to onset of mood episodes during pregnancy or within four weeks of childbirth (see "Bipolar disorder in postpartum females: Epidemiology, clinical features, assessment, and diagnosis")

Bipolar disorders — The diagnosis of bipolar disorder and related conditions are described here; further information on their clinical presentation is discussed separately. (See "Pediatric bipolar disorder: Clinical manifestations and course of illness", section on 'Clinical presentation'.)

The following subtypes of bipolar disorder are included in DSM-5-TR [3]:

●Bipolar I disorder

●Bipolar II disorder

●Cyclothymic disorder

●Other specified bipolar disorder

Difficulties in diagnosing bipolar disorder may lead clinicians to underdiagnose or overdiagnose the disorder. Misdiagnosis is due in part to the overlap between the symptoms of bipolar disorder and the symptoms of other psychiatric disorders, particularly ADHD and behavior disorders. (See 'Differential diagnosis' below.)

Bipolar I disorder — Bipolar I disorder is diagnosed in patients with one or more manic episodes (table 1). Nearly all patients also suffer at least one episode of major depression (table 4), and hypomania (table 3) often occurs as well.

Bipolar II disorder — Bipolar II disorder is diagnosed in patients with a history of at least one hypomanic episode (table 3) and at least one major depressive episode (table 4), and no history of manic episodes (table 1).

Cyclothymic disorder — Cyclothymic disorder is characterized by numerous periods of hypomanic symptoms that fall short of meeting criteria for a hypomanic episode, and numerous periods of depressive symptoms that fall short of meeting criteria for a major depressive episode [3,27]. The symptoms recur over a time interval of at least one consecutive year, during which patients are symptomatic at least half the time and are not symptom-free for more than two consecutive months.

Other specified bipolar and related disorder — Other specified bipolar disorder applies to patients with bipolar symptoms that cause significant distress or impair psychosocial functioning but do not meet the DSM-5-TR criteria for a specific bipolar disorder due to an insufficient number of symptoms and/or an insufficient duration of the symptoms [3,28]. Clinicians record the diagnosis “other specified bipolar disorder,” followed by the reason that the presentation does not meet full criteria for a specific bipolar disorder. Examples of syndromes that can be classified as other specified bipolar disorder include:

●Short duration hypomanic syndromes (two to three days) and major depressive episodes – This other specified bipolar disorder diagnosis is the most common and applies to patients with a lifetime history of at least one major depressive episode who have never met full criteria for mania or hypomania, but have experienced two or more periods that lasted for only two or three days, which otherwise met full criteria for a hypomanic episode. These short duration hypomanic syndromes do not overlap in time with the major depressive episodes, so the disorder is not diagnosed as major depressive episode with mixed features.

●Hypomanic symptoms and major depressive episodes – Other specified bipolar disorder applies to patients with a lifetime history of at least one major depressive episode who have never met full criteria for mania or hypomania but have experienced at least one period that lasted for at least four consecutive days, during which the patient had hypomanic symptoms insufficient in number to meet full criteria for a hypomanic episode. These hypomanic symptoms do not overlap in time with the major depressive episodes, so the disorder is not diagnosed as major depressive episode with mixed features.

●Hypomanic episodes without prior major depressive episode – Patients with a lifetime history of one or more hypomanic episodes, who have never met full criteria for mania or major depression, are diagnosed as other specified bipolar disorder, hypomanic episodes without prior major depression.

●Short duration cyclothymia – Patients who meet criteria for cyclothymic disorder with the exception that the syndrome has lasted for less than 12 consecutive months are diagnosed as other specified bipolar disorder, short duration cyclothymia.

Other specified bipolar disorder is not less severe than bipolar I disorder or bipolar II disorder. Rather, the three disorders are comparable with regard to percent of time symptomatic, frequency of suicidal ideation and suicide attempts, degree of psychosocial impairment, prevalence of psychiatric comorbidity (eg, ADHD and substance use disorder), and number of psychiatric hospitalizations [1,28,29].

Many patients with other specified bipolar disorder develop bipolar I disorder or bipolar II disorder [30]. In a prospective study of 140 youth with other specified bipolar disorder, 45 percent converted to bipolar I or bipolar II disorder [31].

Mood disorder specifiers — DSM-5-TR uses the following terms to specify the course of illness in bipolar I or II disorder [3]:

●Rapid cycling – Rapid cycling is defined as four or more mood episodes (mania, hypomania, or major depression) during a 12-month period (see "Rapid cycling bipolar disorder: Clinical features and diagnosis"). In the past some youths were diagnosed with ultrarapid cycling, but this is no longer used because it seems that the rapid variations in mood occur during an episode and are not separate mood episodes.

●Seasonal pattern – In places with seasons, a seasonal pattern refers to a regular temporal relationship between the onset of at least one type of mood episode (mania, hypomania, or major depression) and a particular time of year, for the past two years. Remission (or change in polarity) also occurs at a specific time of year. The other types of episodes need not follow a seasonal pattern. As an example, episodes of bipolar II major depression may begin each winter and remit in spring, whereas hypomanic episodes do not have to occur at one specific time of year. In addition, the lifetime number of seasonal manias, hypomanias, or depressions substantially outnumbers the nonseasonal episodes (eg, ratio of three to one).

In bipolar disorder with seasonal pattern, depressive episodes occur more often in winter than summer [32]. By contrast, hypomanic/manic episodes occur more often in spring and summer, compared with fall and winter. A seasonal pattern may be more common in bipolar II disorder than bipolar I disorder and unipolar major depression [3,33].

Seasonal pattern is not used as a specifier if a type of mood episode occurs in response to a seasonally related psychosocial stressor (eg, parental unemployment every winter leads to depression). In youths, the autumnal seasonal pattern of depression may be confounded with social and academic stress during the school years in places in which winter coincides with the academic year. Nevertheless, the recurrent onset of depression during fall or winter, which remits as the duration of light increases when the youths are still at school and subject to social and academic stressors (eg, May and early June), is consistent with a diagnosis of seasonal pattern.

Diagnostic stability — The short-term diagnostic stability of bipolar disorder appears to be high. In a retrospective study of 72 youth who were diagnosed with bipolar disorder and followed for a median of four years, 96 percent retained the diagnosis [30]. However, the subtype of bipolar disorder often changed. As an example, bipolar I disorder was diagnosed initially in 38 percent, and at follow-up in 63 percent.

DIFFERENTIAL DIAGNOSIS — 

The primary psychiatric conditions in youth that can be difficult to differentiate from bipolar disorder are:

●Attention deficit hyperactivity disorder (ADHD)

●Autism spectrum disorder

●Borderline personality disorder

●Conduct disorder

●Disruptive mood dysregulation disorder (DMDD)

●Oppositional defiant disorder

●Schizophrenia and schizoaffective disorder

●Substance use disorder

●Unipolar major depression

ADHD, conduct disorder, oppositional defiant disorder, and DMDD — Attention deficit hyperactivity disorder (ADHD), conduct disorder, oppositional defiant disorder, and disruptive mood dysregulation disorder (DMDD) are the conditions most likely to be confused with pediatric bipolar disorder. DMDD is a relatively new and controversial diagnosis in DSM-5-TR that essentially includes youths with severe oppositional defiant disorder.

Symptoms of bipolar disorder that can also occur in these other disorders include increased energy, silliness, and temper outbursts. Clinical features that help distinguish bipolar disorder from these other disorders are listed in the tables (table 5 and table 6 and table 7). Symptoms that are frequently observed episodically and concurrently in bipolar disorder, and very rarely in these other conditions, include the following:

●Euphoria

●Grandiosity

●Decreased need for sleep

●Hypersexuality (in the absence of a history of sexual abuse or exposure to sexual activity)

●Delusions and/or hallucinations

In addition, the course of symptoms over time helps differentiate bipolar disorder from ADHD, conduct disorder, oppositional defiant disorder, and DMDD. Prolonged presentations of manic-like symptoms that do not change in overall intensity suggests a psychiatric diagnosis other than bipolar disorder. As an example, chronic hyperactivity, distractibility, or recklessness should not be considered evidence of mania unless they co-occur with other manic symptoms and intensify with the onset of abnormal mood.

The diagnosis of ADHD and oppositional defiant disorder are discussed separately. (See "Oppositional defiant disorder: Epidemiology, clinical manifestations, course, and diagnosis", section on 'Diagnosis' and "Attention deficit hyperactivity disorder in children and adolescents: Clinical features and diagnosis", section on 'Diagnosis'.)

Unipolar major depression — Episodes of major depression occur in both unipolar major depression (major depressive disorder) and bipolar disorder; however, patients with bipolar disorder have a lifetime history of manic/hypomanic episodes (table 1 and table 3), whereas patients with unipolar major depression do not [3]. Nevertheless, bipolar disorder is often misidentified as unipolar major depression for the following reason: the mood episode at onset of bipolar disorder is often a depressive episode, multiple episodes of major depression may occur prior to the first lifetime episode of mania or hypomania, and depressive symptoms occur more frequently than mood-elevated symptoms [1,34]. In addition, clinicians and patients may not recognize mania/hypomania due to the presence of comorbid disorders.

The diagnostic criteria for bipolar major depression and unipolar major depression are similar, there are no pathognomonic signs that distinguish the two, and it is difficult to differentiate them despite close longitudinal follow-up [3,35-37]. However, replicated findings suggest that among youth with unipolar depression, the following symptoms may indicate susceptibility to eventually developing bipolar disorder [14,15,36]:

●Psychotic features such as delusions and hallucinations

●Early age of onset (eg, <12 years) of first lifetime episode of major depression

●Subsyndromal symptoms of mania

●Emotional and behavioral dysregulation

●Family history of bipolar disorder, particularly a parent with early onset bipolar disorder (eg, <25 years old)

Depressed youths thus need to be followed longitudinally with ongoing assessment for the presence of manic or hypomanic symptoms.

The diagnosis of pediatric unipolar major depression is discussed separately. (See "Pediatric unipolar depression: Epidemiology, clinical features, assessment, and diagnosis", section on 'Unipolar major depression'.)

Schizophrenia and schizoaffective disorder — Bipolar I disorder with psychotic features, schizophrenia, and schizoaffective disorder can each present with delusions and hallucinations. However, in bipolar I disorder with psychotic features, delusions and hallucinations occur only during episodes of mania or major depression [3]. By contrast, patients with schizophrenia and schizoaffective disorder suffer psychotic symptoms in the absence of mood episodes. (See "Schizophrenia in children and adolescents: Epidemiology, clinical features, assessment, and diagnosis".)

Autism spectrum disorder — Youth with mild or “high-functioning” autism may have symptoms such as mood lability, aggression, and agitation, which can be misdiagnosed as bipolar disorder. However, autism spectrum disorder is distinguished from bipolar disorder by clinical features that do not manifest in bipolar disorder, including persistent deficits in social-emotional reciprocity, nonverbal communication behaviors, and developing and maintaining social relationships [3]. (See "Autism spectrum disorder in children and adolescents: Clinical features" and "Autism spectrum disorder in children and adolescents: Evaluation and diagnosis".)

Substance use disorder — Substance use disorder and bipolar disorder can both induce severe mood changes, distractibility, and decreased need for sleep. In addition, youth with bipolar disorder are at higher risk for comorbid substance use disorder, which in some cases may serve as a means of coping with problems inherent in bipolar disorder [5,38]. However, bipolar disorder is not diagnosed if mood episodes are due to the effects of an illicit drug or substance misuse [3]. Rather, bipolar disorder is diagnosed if mood episodes occur when the patient is not using substances. (See "Substance use disorder in adolescents: Epidemiology, clinical features, assessment, and diagnosis".)

Borderline personality disorder — The alternating mood syndromes ("mood swings") and irritability of bipolar disorder can resemble the affective instability and uncontrolled anger of borderline personality disorder [3]. Recurrent suicidal ideation and behavior, impulsivity (eg, excessive spending sprees, sexual promiscuity, substance use disorder, and reckless driving), and poor psychosocial functioning are also common to bipolar disorder and borderline personality disorder. The differential diagnosis can be especially complicated in youth with bipolar disorder who also have subsyndromal or syndromal borderline personality disorder [39,40].

Nevertheless, several clinical features distinguish the two disorders [3]:

●Borderline personality disorder is marked by unstable and intense interpersonal relationships, identity disturbance (fluctuating self-image or sense of self), chronic feelings of emptiness, and frantic efforts to avoid abandonment; these features are not characteristic of bipolar disorder.

●The depressive or mood-elevated syndromes in bipolar disorder are longer in duration (eg, lasting days to weeks) compared with the labile affective states of borderline personality disorder (eg, lasting minutes to hours).

●Bipolar mood syndromes are less connected to events in the environment; by contrast, the mood lability of borderline personality disorder is often triggered by stressors such as perceived rejection or failure.

●A family history of bipolar disorder in first degree relatives suggests bipolar disorder rather than borderline personality disorder.

Medication reactions — Medications such as antidepressants may trigger symptoms of mania (table 1) or hypomania (table 3) in youth [4]. In these cases, mania or hypomania is not diagnosed if mood-elevated symptoms are attributable to a medication [3]. However, if mania/hypomania arises during treatment with an antidepressant and the full syndrome persists beyond the physiologic effect of the medication, the syndrome is classified as an episode of mania or hypomania.

Alternatively, exposure to antidepressants or other medications (eg, bronchodilators, corticosteroids, and stimulants) may lead to activation and arousal that overlaps with bipolar disorder, by virtue of symptoms that are common to both, including giddiness, silliness, talkativeness, distractibility, disinhibition, and increased activity [4,41]. However, most youth who respond to medications with activation and arousal do not have bipolar disorder [41]. The severity and length of medication-induced symptoms do not rise to the level of mania/hypomania. In addition, medication reactions do not include symptoms that are observed in bipolar disorder, such as hypersexuality and spending sprees.

Antidepressant-induced activation may occur in up to 10 percent of children and adolescents treated with antidepressants [42,43]. Activation is typically observed at the beginning of treatment and resolves quickly once the dose is lowered or the drug is discontinued. Nevertheless, it is important to monitor patients who become activated.

Other medical conditions — Other medical and neurologic illnesses (eg, head trauma, brain tumors, and hyperthyroidism) may be accompanied by symptoms that mimic bipolar disorder, such as distractibility and psychomotor agitation. However, these other illnesses manifest clinical features, as revealed in the history of the present illness and on physical examination and laboratory testing, which are not evident in bipolar disorder.

SOCIETY GUIDELINE LINKS — 

Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Bipolar disorder".)

SUMMARY AND RECOMMENDATIONS

●When to suspect the disorder – Primary care clinicians should be alert to symptoms, particularly if they are concurrent and episodic, which suggest the possibility of pediatric bipolar disorder:

•Increased activity and/or silliness beyond what is expected for the child’s developmental age

•Decreased need for sleep

•Depression with psychotic features (eg, hallucinations and/or delusions)

(See 'When to suspect the disorder' above.)

●Assessment

•Who should assess the patient – Pediatric patients in whom bipolar disorder is strongly suspected should be evaluated by a mental health specialist, unless the primary care clinician has extensive experience with the disorder. Multiple interviews may be required to make the diagnosis. (See 'General approach' above.)

•Specific elements – Assessment of youth for bipolar disorder begins with the history of present illness, including manic, hypomanic, and depressive symptoms; suicidal and homicidal ideation; psychotic features; comorbid disorders; psychosocial functioning; and treatment. The evaluation also includes the past psychiatric history, family psychiatric history, social history, and mental status examination. (See 'Specific elements' above.)

●Diagnosis

•Diagnostic challenges – The diagnosis of pediatric bipolar disorder can be complex because youth with the disorder frequently have a variable course with rapid fluctuation in mood symptoms during acute episodes, developmental issues that complicate the assessment of symptoms and behaviors, and difficulty verbalizing their emotions and symptoms. (See 'Diagnostic challenges' above.)

•Bipolar mood episodes – The Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, Text Revision (DSM-5-TR) is generally used to diagnose bipolar mood episodes, including mania (table 1), hypomania (table 3), and major depression (table 4). (See 'Mood episodes' above.)

•Bipolar disorders

-Bipolar I disorder – Bipolar I disorder is diagnosed in patients with one or more manic episodes. Nearly all patients also suffer at least one episode of major depression, and hypomania often occurs as well. (See 'Bipolar I disorder' above.)

-Bipolar II disorder – Bipolar II disorder is diagnosed in patients with a history of at least one hypomanic episode and at least one major depressive episode, and no history of manic episodes. (See 'Bipolar II disorder' above.)

-Cyclothymic disorder – Cyclothymic disorder is diagnosed in patients with periods of hypomanic symptoms that fall short of meeting criteria for a hypomanic episode, and periods of depressive symptoms that fall short of meeting criteria for a major depressive episode. Symptoms recur over a time interval of at least one year. (See 'Cyclothymic disorder' above.)

-Other specified bipolar disorder – Patients with recurrent manic/hypomanic symptoms that cause significant distress or impair psychosocial functioning but do not meet the full criteria for a specific bipolar disorder are diagnosed with other specified bipolar disorder. (See 'Other specified bipolar and related disorder' above.)

●Differential diagnosis – Attention deficit hyperactivity disorder, conduct disorder, oppositional defiant disorder, and disruptive mood dysregulation disorder are the conditions most likely to be confused with pediatric bipolar disorder (table 5 and table 6 and table 7). The differential diagnosis of bipolar disorder also includes unipolar major depression, schizophrenia, autism spectrum disorder, and substance use disorder. (See 'Differential diagnosis' above.)