Approach to diagnosing bipolar disorder in adults and young people

Diagnosis of bipolar disorder requires an accurate history about past mood episodes (see Features of bipolar disorder), including their number, frequency, intensity and duration. See here for characteristics of common bipolar disorder subtypes. Refer to a psychiatrist to confirm the diagnosis.

Often a patient will initially present with a depressive episode; a diagnosis of bipolar disorder can only be made once an episode of mania or hypomania occurs. Hypomania can be particularly difficult to recognise because patients rarely seek treatment during a hypomanic episode. Ask all patients presenting with depressive symptoms about possible prior episodes of hypomania or mania, or a family history of bipolar disorder.

If a patient presents with manic or hypomanic symptoms, exclude other causes of their symptoms. If the patient has psychotic symptoms, also consider alternative causes of psychoses—see Assessments to help identify cause(s) of psychotic signs and symptoms. Consider an underlying physical disorder (eg neurological, endocrine), particularly in patients older than 40 years because a first episode of mania is uncommon in this group; the peak onset of bipolar disorder is in young people.

Symptoms of bipolar disorder often overlap with other psychiatric disorders, such as major depression, personality disorder, attention deficit hyperactivity disorder (ADHD), schizophrenia and anxiety disorders, which can lead to misdiagnosis and consequently incorrect treatment. Approximately 50% of patients have concurrent alcohol or other substance problems, or an anxiety disorder. Correct diagnosis of bipolar disorder is often delayed by years, and consequently management may be suboptimal during this time.