The management of bipolar disorder in general practice

It has been estimated that 1 in 200 Australians experiences an episode of bipolar disorder in any 12-month period,1 and that lifetime prevalence is between 1% and 4%.2

The Australian National Study of Low Prevalence (Psychotic) Disorders included an analysis of 112 people meeting the criteria for bipolar disorder of the International classification of diseases, 10th revision (ICD-10).3 Most were already in treatment, and might therefore reflect the more severe or acute segment within the continuum of severity.

The mean age of onset was 25 years for men and 26 years for women. In addition to episodes of mania, 79% had experienced at least one clinically significant episode of depression. A large proportion (86%) reported experiencing delusions at some time in their lives.

Difficulty with relationships was common. Just over half the men and a quarter of the women were single and had never been in a long-term relationship, and 64% of the men and 42% of the women did not have children. Half the men and a third of the women lived alone. Many had achieved well educationally, but their work performance was impaired: only 30% of both men and women with bipolar disorder had no formal secondary school qualifications, but 79% were receiving a pension or benefit, and 67% of those seeking work were unemployed at the time of interview; 9.8% were classified as severely disabled.

• Bipolar I disorder is characterised by the occurrence of at least one lifetime episode of mania and, usually, episodes of depression.

• Bipolar II disorder is characterised by episodes of both hypomania and depression, but no manic episodes.

• Recognised patterns of illness also include mixed states and rapid cycling between depression and mania.

Depression is often the predominant mood and has been associated with the greatest burden of disability. One study found that patients with bipolar I disorder experienced 32% of their weeks of follow-up in depression and 9% in mania or hypomania. For those with bipolar II disorder, 50% of their follow-up period occurred in depression but only 1% in hypomania.4

Suboptimal function between discrete bipolar episodes, characterised by symptoms such as mild anxiety or depression, is common and tends to be unrecognised. The suicide rate in people with bipolar disorder is about 15 times that of the general population, and 80% of suicides occur during episodes of depression. At least 25% of patients will attempt suicide and 10%–20% will complete suicide. Comorbid conditions including anxiety disorders (52% of patients in one Australian study) and substance misuse (39%) are prevalent.1

GPs are well placed to coordinate the care of patients with bipolar disorder as they continue to provide other aspects of general medical care and develop an understanding of the patient’s circumstances and progress.

There is increasing interest in shared care between the primary and secondary care sectors for patients with mental illness.5 It is appropriate for a psychiatrist to assess patients with bipolar disorder early in the illness, to make or confirm the diagnosis and establish a plan for medication and psychological management. Most GPs treat relatively few patients with bipolar disorder, and continuing care for those with severe or frequently recurring illness might best be directed by specialist services. Those with less severe illness, or illness that is responsive to treatment, might best be managed primarily by GPs.

Patients with bipolar disorder report that delays in diagnosis and incorrect diagnosis are common. A study of participants in a bipolar disorder support group revealed that more than a third sought professional help within a year of the onset of symptoms, but 69% were misdiagnosed, most frequently with unipolar depression.6 Other frequently reported misdiagnoses included anxiety disorder, schizophrenia, borderline or antisocial personality disorder, alcohol or substance misuse and/or dependence, and schizoaffective disorder.6 Over a third waited 10 years or more before receiving an accurate diagnosis. Notably, respondents rarely reported all their manic symptoms to a doctor. For example, fewer than a third admitted symptoms such as reckless behaviour, spending excessively and increased sexual interest or activity.6

The age of the patient influences the differential diagnosis. In younger patients, conditions such as attention deficit hyperactivity disorder and conduct disorder need to be considered. In patients older than 40 years — an age when initial presentation in the manic phase of bipolar disorder is relatively uncommon — possible organic causes should be addressed.

Some “clues” to the presence of bipolar disorder are summarised in Box 1. Note that longitudinal monitoring is often necessary to make or refine the diagnosis.

There is growing evidence for the benefits of psychological therapies in bipolar disorder.12-15 Psychological therapies include:

• education about the condition and its treatment;

• basic cognitive behavioural techniques (eg, identifying triggers and planning how to minimise or avoid them; accurately labelling emotions; identifying thoughts and reframing them into more positive rational responses; and dealing with adjustment/self-esteem issues and long-term vulnerabilities);

• interpersonal and social rhythms therapy teaches patients to be more effective in handling relationships and make graded lifestyle changes to increase stability, and highlights the importance of routine and sleep;

• supportive psychotherapy is particularly useful in identifying interpersonal triggers that affect the patient’s mood. It is most useful in the maintenance stage of treatment, once the skills of cognitive behavioural therapy have been learned; and

• exercise, yoga, relaxation therapy and similar “mind–body” interventions, individualised to the needs and lifestyle of the patient, may also be beneficial in the maintenance stage.

Indications for referral to specialist services are given in Box 4.

Bipolar disorder can be extremely taxing for the family and carers of the patient. Families need and want information and education about the illness, as well as continuing support during times of crisis. They can become active participants in elements of treatment such as encouraging appropriate medication, regulating lifestyle and monitoring the patient for signs of relapse (Box 5).

Bipolar disorder is a challenging illness for patients, families and carers, as well as for health care professionals. Increased understanding of the disorder can facilitate early and accurate diagnosis, effective short-term and long-term pharmacological and psychological treatment, and the development of effective support mechanisms.

GPs have a central role in facilitating diagnosis, accessing specialist care, and providing continuing monitoring and support.