Bipolar II disorder often missed

ALL patients with clinical depression should be screened for bipolar disorder because the condition is often misdiagnosed and mistreated, according to mental health experts.

The comments were made in response to two articles in the latest MJA, which reflect on the case of Charmaine Dragun, a 29-year-old TV newsreader who suicided off The Gap in Sydney in late 2007. A coronial inquest identified that a likely contributor to her suicide was the failure of several health practitioners including GPs, psychologists and psychiatrists to diagnose bipolar II disorder.

Professor Gordon Parker, a psychiatrist and executive director of the Black Dog Institute, wrote that the Dragun case indicated the need for enhanced awareness of bipolar II disorder among health practitioners. (1)

He told MJA InSight that about 20% of psychiatrists “don’t believe” in bipolar II disorder, despite its high suicide rate.

Bipolar II disorder is not as symptomatically severe as bipolar I, and involves episodes of non-psychotic hypomania alternating with melancholic depression.

Professor Parker said the missed diagnosis at the centre of the Dragun case was sadly not exceptional.

“I hear this story a few times a week in new patients. I’ve just seen two people today with the same story. In both cases the interval from onset of symptoms to being referred to us with possible bipolar was about 10 years.”

Professor Parker said that, as an experienced psychiatrist, he believed diagnosing bipolar II disorder was not difficult or time consuming.

He suggested that GPs or psychologists should inquire about mood swings in patients with depression by asking if they had experienced times when they were very energised or wired, spending more money or not needing to sleep.

If people with depression did report these energised moods, Professor Parker said doctors who were not experienced in diagnosing bipolar II could suggest that patients take the Black Dog Institute’s online self-test.

“The test has an 80% level of confidence, and [each month] about 50 000 people do it”, he said.

Associate Professor Greg Murray, head of psychological sciences and statistics at Swinburne University, said identifying bipolar II could be difficult because people tend to present to a health practitioner when in a depressed phase.

“Their depressed mood may make it impossible for them to recall times when they were not depressed.” He said there was a fine line between hypomania and “a really good weekend”.

Professor Murray and Professor Parker emphasised that people with bipolar II disorder generally had melancholic depression, characterised by symptoms such as psychomotor disturbance, anhedonia, and diurnal mood variation.

“If the person sitting in front of you has depression with a heavy biological flavour it’s a cue to hunt for evidence of bipolar disorder”, Professor Murray said.

Professor Parker and Professor Murray agreed that patients with bipolar II are best managed using a team approach.

“GPs who are educated in managing bipolar II may want to manage it — that’s fantastic. If not, my advice is to refer the patient to a psychiatrist who is experienced in bipolar II to clarify the diagnosis and get the patient’s mood swings under control. Then a collaborative endeavour with a psychologist, running a ‘stay well’ plan, is the best approach”, Professor Parker said.

An accompanying editorial in the MJA explained that doctors have an obligation to refer patients when another practitioner is better placed to advance the patients’ interests. (2)

The consequences of misdiagnosing bipolar II disorder as unipolar depression were severe.

Professor Parker said people with bipolar II disorder were more likely to require mood stabilisers than antidepressants. There was a lot of evidence that antidepressants could worsen the bipolar disorder by inducing more rapid cycling of symptoms and increasing the frequency of episodes, he added.

- Sophie McNamara

1. MJA 2011; 195: 81-83
2. MJA 2011; 60-61

Posted 18 July 2011

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