By Clinical Partners on Monday, 01 April 2019
Category: Bipolar Disorder

Why bipolar disorder is often misdiagnosed

Bipolar is one of the most common, yet debilitating mental health conditions in the UK. Affecting every area of your life from relationships to work to socialising, Bipolar also increases your risk of suicide 20 fold4. With the right treatment, Bipolar can be successfully managed, and those with the disorder can go on to live happy, fulfilling lives.

One of the biggest hurdles for anyone with Bipolar Disorder isn’t the treatment routine itself, but simply getting the right diagnosis in the first place. Of all the mental health disorders, Bipolar is perhaps one of the most commonly misdiagnosed – but why?

The following is a list of five reasons bipolar disorder might be misdiagnosed.

1. Bipolar depression is hard to distinguish from other conditions

Bipolar disorder can be confused with other mental health conditions, such as ADHD or ‘unipolar’ depression. The manic episodes associated with Bipolar may not be obvious. They can be mistaken for other behaviours such as those commonly found with ADHD (rapid speech, inability to concentrate) because the person may not have had a manic episode until later in life. The beginning of bipolar disorder tends to be characterised by a depressive episode rather than the manic/hypomanic episodes we hear so much about in the press5.

Symptoms of bipolar disorder look very similar to unipolar depression. If the manic periods are not memorable, recalled easily or frequently, it may be that the clinician bases the diagnosis on the patient’s current presentation.

However, even when the patient has had manic or hypomanic episodes, bipolar disorder can still be misdiagnosed. This is likely related to two points: Hypomania can go unnoticed, and clinicians do not always get all the necessary information.

What is Hypomania?


Hypomania refers to an elevation in mood that is less drastic than mania. Hypomania may sometimes be enjoyable due to the increased energy and confidence that often come with it. However, it can still lead to impulsive behaviour with adverse consequences, such as overspending and damaging personal relationships. Because it is more subtle in how it is experienced, it is harder to pick up.


Because it is enjoyable, people with bipolar II may not seek treatment during a hypomanic episode. Research suggests that people with bipolar II are more likely to seek treatment for a depressive episode than a hypomanic episode. Hypomania does not tend to involve psychotic symptoms (hallucinations and delusions), or a serious ‘break from reality.’ Furthermore, hypomania does not tend to end in hospitalisation, as mania sometimes does.

Hypomania is therefore less likely to be recognised by mental health professionals, the person with h bipolar II or their family and close friends. This could explain the research finding that misdiagnosing bipolar disorder as unipolar depression is more common in bipolar type II than in bipolar type I7.

People with bipolar II may not deliberately withhold a history of hypomania from the clinician. Still, they may not mention it either because they might not recognise a past hypomanic episode for what it was. Furthermore, depressive episodes for people with bipolar II are far more common than hypomanic episodes (Judd et al., 2003). This would make hypomanic episodes stand out less than depressive episodes.

3. Clinicians don’t get enough information

Sometimes it can be difficult to get a full history of someone’s mental health problems – a key part of any psychiatric assessment. This can be for several reasons.

Sometimes the person with bipolar disorder doesn’t have an accurate memory of their mood states in the past. They may have misinterpreted a previous hypomanic episode as a good phase of their life or a period of stability in between depressive episodes.

It can be really hard for someone with Bipolar to accurately recall their moods and when they happened, – depressive and manic states make it hard to remember the detail of what you experienced. Anyone with a mental health illness will know how hard it is to verbalise their symptoms and experiences and therefore be able to describe them to a Psychiatrist clearly.

Ideally, the diagnosing clinician will be able to speak to the individual’s family or partner to understand another more objective view of the symptoms – but this isn’t always possible, and often people with Bipolar feel shame or embarrassment with their symptoms.

4. The person has another condition that complicates the diagnosis

Another reason bipolar may be misdiagnosed is if a more ‘pressing’ or immediate mental health condition overshadows the Bipolar.

For example, people with Autistic Spectrum Disorder who also have bipolar disorder may not receive an accurate diagnosis because of what is called ‘diagnostic overshadowing.’ This refers to when symptoms of bipolar disorder are interpreted as Autistic traits, and it may happen because there are overlaps in symptom presentation8. People with ASD and bipolar disorder are also more likely to have mood states with mixed or atypical features, such as irritability and aggression as opposed to euphoria, which can also make an accurate diagnosis more difficult9.

5. There are many types of bipolar

There are multiple subtypes of bipolar disorder. As well as bipolar types I and II, there is cyclothymic disorder (many periods of hypomania and depressive symptoms which do not meet the criteria for a depressive episode), and bipolar disorder not otherwise specified (depressive and hypomanic symptoms that do not meet the criteria for bipolar I, bipolar II or cyclothymia).

Sometimes it may not be clear which subtype the person’s symptoms best fit. This may be because the clinician has an incomplete or inaccurate history of the patient’s mood states.

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