Can bipolar disorder and Attention Deficit Hyperactivity Disorder (ADHD) occur together?

Bipolar Disorder and ADHD Comorbidity

Yes, bipolar disorder and Attention Deficit Hyperactivity Disorder (ADHD) can frequently occur together, with approximately 20% of adults with bipolar disorder having comorbid ADHD, and about 20% of adults with ADHD having comorbid bipolar disorder. 1, 2

Diagnostic Considerations

• Distinguishing between these disorders is challenging due to overlapping symptoms including impulsivity, distractibility, hyperactivity, and emotional dysregulation 3, 2

• The course of illness differs significantly:

  • Bipolar disorder is episodic with periods of normal mood between episodes 3
  • ADHD presents as chronic, trait-like symptoms and impairments 3, 2

• Key differentiating factors:

  • Age of onset: ADHD typically begins before age 7, while bipolar disorder usually emerges after age 12 2
  • Mood symptoms: Always present in bipolar disorder but not a core feature of ADHD 2
  • Psychotic symptoms: May occur in bipolar disorder but are absent in ADHD 2

• When comorbid, bipolar disorder tends to have an earlier onset (approximately 4 years earlier) and a more severe clinical course 1, 2

Diagnostic Challenges in Children and Adolescents

• The validity of bipolar disorder diagnosis in young children remains controversial, with particular caution needed in preschool children 4

• Symptoms that may be confused between disorders:

  • Manic-like behaviors in children with ADHD (excessive silliness, grandiosity) can be commonplace in youth with disruptive behavior problems 4
  • Irritability can be present in both conditions but differs in quality and pattern 4

• Follow-up studies show that manic symptoms in boys with ADHD often do not persist or evolve into DSM-defined bipolar disorder 4

Treatment Implications

• When both disorders coexist, the consensus expert recommendation is to treat bipolar disorder first before addressing ADHD symptoms 3, 5

• Treatment considerations:

  • Mood stabilizers and atypical antipsychotics are primary treatments for bipolar disorder 4
  • Stimulants may be used for ADHD symptoms once mood is stabilized 4
  • A randomized controlled trial of 40 bipolar children and adolescents with ADHD demonstrated that low-dose mixed amphetamine salts were safe and effective for treating ADHD symptoms once mood was stabilized with divalproex 4

Medication Precautions

• FDA labeling for stimulants warns: "Particular care should be taken in using stimulants to treat ADHD in patients with comorbid bipolar disorder because of concern for possible induction of a mixed/manic episode in such patients" 6

• Similarly, atomoxetine labeling cautions about screening for bipolar disorder before initiating treatment 7

• Despite concerns, studies challenge the belief that stimulants necessarily precipitate progression to bipolar disorder:

  • Two studies found that boys with ADHD plus manic-like symptoms responded as well to methylphenidate as those without manic symptoms 4
  • Stimulant treatment did not precipitate progression to bipolar disorder in these studies 4

Monitoring and Long-term Management

• Regular monitoring is essential for:

  • Symptom changes and potential medication side effects 4
  • Weight and growth in children and adolescents 6, 7
  • Cardiovascular parameters, especially with stimulant medications 6

• Most patients with bipolar I disorder will require ongoing medication therapy to prevent relapse, with some needing lifelong treatment 4

• The risk of relapse is high when maintenance therapy is discontinued, with one study showing >90% of adolescents who were non-compliant with lithium treatment relapsed 4

Clinical Pitfalls to Avoid

• Misattributing symptoms of one disorder to the other, leading to inappropriate treatment 3, 2

• Failing to recognize comorbidity, which occurs in approximately 20% of cases 1, 2

• Assuming that activation or irritability from stimulants or SSRIs automatically indicates bipolar disorder 4

• Discontinuing effective treatment too early, particularly for bipolar disorder where maintenance therapy is often needed for 12-24 months or longer 4