The etiology of BD is multifactorial. Studies in BD point to a highly familial etiology with family history of mental illness, including major depression, BD, schizophrenia, or ADHD. A first-degree relative with BD leads to a 10-fold increase in a child’s chance of developing BD. An earlier onset of BD in a parent increases the risk of early onset BD in offspring with a more chronic and debilitating course that may be less responsive to treatment.
The differential diagnosis for BD includes ADHD, major depression, conduct disorder (CD), mood disorder due to a general medical condition, substance-induced mood disorder, pervasive developmental disorder, and schizophrenia.
Patients with BD often have concurrent conditions that warrant treatment. ADHD occurs in approximately 60% to 90% ofchildren with BD. Anxiety disorders also commonly occur withBD and do not respond to antimanic agents. Substance abusecan precipitate and perpetuate mania and depression. The alteration between highs and lows related to some types of substanceabuse often mimics BD. Patients with BD may also self-medicate in attempts to alleviate symptoms. Many patients with BDmay commit crimes and meet criteria for CD due to aggressionand impulsivity. Prominent symptoms of mania assist in differentiating between CD and BD. Patients with BD generallyexhibit reactive aggression, whereas those with CD are morelikely to preplan and develop a typical pattern of crimes.
No laboratory or imaging studies can diagnose BD. Physical examination, careful history, review of systems, and laboratory testing are done to rule out suspected medical etiologies, including neurologic and substance-induced disorders.
Treatment of BD includes decreasing acute symptoms. The FDA has approved lithium, divalproex sodium, carbamazepine, olanzapine, risperidone, quetiapine, ziprasidone, and aripiprazole for adults with BD. Lithium is the oldest proven treatment for mania in adults and has been used effectively in children and adolescents for years. Common side effects of lithium include hypothyroidism, polyuria, and acne. Divalproex is also a first-line agent (preferable for mixed or rapid cycling cases) for adults. It has been used effectively for decades in youth, but it is not FDA-approved. Periodic monitoring of blood levels for select medications (lithium and divalproex sodium) can help ensure both treatment safety and the receipt of therapeutic amounts of the medication. Anti-psychotics (risperidone, olanzapine, quetiapine, aripiprazole, and ziprasidone) have had positive results in youth with BD. It is likely that newer antipsychotics will also be effective in BD.
Treating comorbid psychiatric disorders must be done carefully. Stimulants may be used to treat ADHD once the patienthas been stabilized on a mood stabilizer. Antidepressants shouldbe avoided; if the youth is depressed or has significant anxietyand is not responsive to other pharmacotherapy, cautious useof antidepressants may be necessary. Careful monitoring formanic reactivation, cycling, and suicidality is needed.
Cognitive and behavioral therapies are aimed at improving adherence to medication treatments and ameliorating anxiety and depressive symptoms. Psychoeducation and family therapy are needed to stabilize the patient’s environment and improve prognosis. There should be continuous ongoing safety assessment. Because developmental delays are also common in young children with BD due to poor learning while symptomatic, collaboration with school regarding behavioral management, special educational needs, and an appropriate individualized educational plan is also needed.