Bipolar disorder is a common illness that affects 1%–2% of the general population;1 it is therefore often first assessed, and frequently managed, by general practitioners. It usually presents with symptoms of depression, but a diagnosis of bipolar disorder is contingent on the occurrence of an episode of mania or hypomania.2 Consequently, many cases of bipolar disorder remain undetected or are misdiagnosed as major (unipolar) depression. Further, individuals with hypomania rarely seek help, and those with comorbid anxiety or symptoms of depression that do not respond to treatment often resort to self-medication with alcohol or illicit substances. Equally, bipolar disorder is thought to be overdiagnosed in some populations such as adolescents and young adults.3
We synthesised recommendations from recently published guidelines for the treatment of bipolar disorder.4-6 Treatment recommendations are therefore divided into sections on acute bipolar mania, acute bipolar depression and maintenance.
We also conducted a literature search of articles on pharmacological treatment of bipolar disorder that were published up to May 2009 — using electronic databases (MEDLINE, PubMed, PsycINFO), book chapters and articles known to the authors — to identify Cochrane reviews, meta-analyses, review articles and reports from randomised controlled trials. The search terms bipolar disorder, mania, pharmacotherapy, general practice, manic–depressive illness and depression were used. Key recommendations relevant to GPs were synthesised and rated according to National Health and Medical Research Council (NHMRC) levels of evidence.7
GPs are integral to the management of bipolar disorder, often with involvement from the initial detection and assessment of the illness through to longer-term management. The GP is usually the first health professional from whom the patient will seek assistance. Alternatively, in instances where the illness emerges insidiously, it may be the GP’s long-term knowledge of the patient that assists in detecting subtle changes in mood and behaviour.
The GP’s role in managing bipolar disorder will vary according to the patient, the severity of the illness and the level of available support. The GP may take on the primary role of treating the patient, with the option of referral to specialist services if and when required. Alternatively, the patient may be primarily managed by an external team, such as a community mental health service, but with links to the GP maintained. Further, multiple professionals are typically involved in working with patients who have a mental illness, including professionals who primarily target clinical interventions and those who target more broad aspects of life affected by the illness, such as social and occupational functioning. While many of the professionals who work with these patients should also communicate with one another, the GP often serves as the focal point around which the other services are provided, including contact with family and carers (Box 1). With respect to pharmacological management, the main priorities for the GP are to assess efficacy, encourage adherence to treatment and monitor for potential side effects. Ideally, treatment plans are developed and initiated following consultation with a psychiatrist, particularly in complex cases, and with referral back to the psychiatrist during periods of increased severity of illness or risk.
If a diagnosis of bipolar disorder is suspected, the first imperative is to act. Action involves careful assessment so as to provide individualised care and effective treatment. Box 2 provides an overview of the management of bipolar disorder, adapted from previously published recommendations.4 In all cases, management should begin with a detailed clinical assessment that includes diagnostic formulation, assessment of safety and risk, a brief medical examination (including baseline investigations and screening for medical illnesses), and implementation of any necessary action such as facilitating an emergency assessment for hospitalisation. Guidelines for baseline and ongoing monitoring in bipolar disorder have been reviewed in detail recently and are summarised in Box 3. The care principles outlined in Box 2 are applicable throughout all stages of treatment and are essential for effective long-term management. An effective collaborative alliance is important for increasing the likelihood that the patient remains engaged in treatment; this can be fostered by providing emotional support and education to the patient and his or her family. Much of this can be initiated by a GP, but prompt transition to joint involvement of a psychiatrist is recommended, especially when affirming diagnosis and planning future management.
Treatment involves implementing strategies to achieve remission of symptoms of acute manic episodes and/or depressive episodes, as well as longer-term maintenance treatment to optimise social and occupational functioning and prevent relapse. In addition, ensuring safety and specifically reducing the risk of suicide is an ongoing consideration throughout all stages of treatment. Pharmacotherapy remains the primary treatment modality, but ideally it is supplemented with psychological interventions; in some instances, specialist physical measures such as electroconvulsive therapy may also be useful. Box 4 provides a detailed overview of side effects and recommended therapeutic dosing for agents commonly used in bipolar disorder.
During acute mania, an assessment of risk including personal safety, reputation and the safety of others should be undertaken. Steps may need to be taken to manage acute mania — for example, hospitalisation or referral for specialist mental health services is often necessary during this phase of illness. Treatments for acute bipolar mania should aim to treat the acute symptoms of mania and to manage any accompanying behavioural disturbance (Box 5).
Where possible, any mania-inducing agents that the patient is already taking (eg, antidepressants and stimulants) should be tapered and ceased. The patient should also be advised to institute general measures to reduce stimulation and maintain a routine, and to delay making important decisions. Restoration of sleep is also important.
With regard to pharmacological treatments, lithium, valproate, atypical antipsychotics, haloperidol and, to a lesser extent, carbamazepine all have indications for acute mania.4-6,9 The choice of agent depends on episode severity, patient preference and likely side effects. While haloperidol is effective in acute mania, it is not a first-line option because of a high risk of extrapyramidal side effects and its inability to prevent depression. If a rapid response is required, valproate or the atypical antipsychotics are preferable to lithium.
If possible, monotherapy should be trialled to reduce the likelihood of adverse effects. However, when there is marked risk or greater severity of illness, or the response to an initial monotherapy trial has not been adequate, combinations such as lithium or valproate combined with an atypical antipsychotic add efficacy.11,12 In general, about 50% of individuals with mania respond to monotherapy with an antimanic agent, and 75% respond to a combination of an atypical antipsychotic and either lithium or valproate.
The adjunctive short-term use of benzodiazepines (eg, lorazepam) may help manage additional behavioural disturbance. However, these are usually tapered within days and gradually withdrawn as symptoms start to abate. If the patient is being treated with an antipsychotic for mania, this may also provide an additional settling effect.
Depression is the predominant phase of bipolar disorder and, as such, it confers substantive risks in terms of morbidity and suicide.13 In comparison to acute mania, the pharmacotherapy for bipolar depression is more complicated and based on data that are less clear. This is reflected in recommendations that are generally less definitive and vary across guidelines (Box 6).
First-line monotherapy options include lithium, valproate, quetiapine and lamotrigine.9 Lithium is particularly noted for its antisuicidal properties, but is disadvantaged by a delay in effect of 2–3 weeks. First-line medication combinations include olanzapine plus fluoxetine,14 and lithium combined with valproate or lamotrigine.15,16 Each agent, or combination of agents, has unique advantages and disadvantages in relation to clinical effectiveness, speed of antidepressant action, tolerability and prophylactic properties.
Unlike the use of antidepressants in unipolar depression, antidepressant use in bipolar disorder is a controversial issue. The effectiveness of conventional antidepressants in bipolar depression is unclear, and three recent large studies have reported no additional benefit from the adjunctive use of antidepressants in bipolar depression.17-20 Further, in some patients, the use of conventional antidepressants is associated with an increased risk of a switch to mania.17,21,22 Nonetheless, antidepressants may benefit a small cohort of patients with bipolar depression but, if used, should be prescribed in combination with a mood-stabilising agent to minimise the risk of affective instability. In this regard, selective serotonin reuptake inhibitors are preferable because they are less likely to induce a switch to mania than other antidepressant classes and are less dangerous in cases of overdose.23
Maintenance treatment (Box 7) is likely to be necessary in most patients with an established diagnosis of bipolar disorder. Following an acute episode, conservative indications for maintenance treatment include instances where there has been at least one other prior mood episode in the past 5 years or two prior episodes across the lifetime, the acute episode was severe and included suicide risk or psychotic features, or there is ongoing functional disability.
Bipolar disorder is a lifelong illness with episodes that can cause marked disruption and stress not only to patients but also their families. When patients present with severe illness or experience frequent relapse, the demands on the treating physician can also be significant. It may be necessary for the GP to broaden the management and include referrals to external health care providers such as psychiatrists, psychologists, social workers and case managers working within community mental health teams.
Following an acute episode, it is important to taper and withdraw any agents (such as benzodiazepines or antipsychotics) that were used to manage temporary behavioural or cognitive disturbance. The goal of pharmacotherapy in maintenance is to prevent relapse. In this regard, lithium is still considered the gold-standard treatment, although it appears to be more effective at preventing manic relapse than depression. Lamotrigine and valproate also have prophylactic properties, with lamotrigine being more efficacious at preventing depressive relapse compared with manic relapse.24,25 Other anticonvulsants (eg, carbamazepine) have been less impressive and are not consistently recommended as first-line treatment options.4,9
There is growing interest in the use of atypical antipsychotics for maintenance treatment, and quetiapine, olanzapine and aripiprazole have been shown to have benefits. Quetiapine appears to be equally effective at preventing both manic and depressive episodes, whereas all other atypical antipsychotics are more effective at preventing manic episodes. While some longer-term evidence is beginning to emerge,26-28 the long-term prophylactic properties of atypical antipsychotics are yet to be reliably established and further research is needed before such agents can be confidently recommended for long-term use in bipolar disorder; there is no clear class effect in this regard.
Again, monotherapy is considered ideal and trials of medications may take several months before effectiveness becomes clear. Nonetheless, a significant proportion of patients will not respond adequately and combination regimens are the rule rather than the exception; this may require further consultation with psychiatrists. Treatment options for patients who experience rapid cycling and mixed episodes are summarised in Box 8.
There are a number of novel agents that have shown promise in initial clinical trials in treating bipolar disorder. While further trials are needed before specific recommendations can be made, such agents include N-acetylcysteine,29 omega-3 fatty acids,30 tamoxifen,31,32 asenapine,33 antiglucocorticoids,34 celecoxib,35 modafinil36 and pramipexole.37
Bipolar disorder is a complex illness but, in most cases, it can be managed effectively once it is detected and the necessary supports and treatments are instituted. The role of the primary care physician is pivotal in the identification of bipolar disorder and its subsequent lifelong management. Suitable treatments are increasingly available but require sophisticated administration. Hence, it is important that health professionals in all areas of medicine are familiar with the management of this common psychiatric illness.
3 International Society for Bipolar Disorders guidelines for baseline and ongoing monitoring in bipolar disorder8
4 Side effects and therapeutic dosing for agents commonly used in bipolar disorder*8-10
6 Summary of treatment for bipolar depression
First-line monotherapy options: lithium, valproate, quetiapine and lamotrigine.
First-line combination options: olanzapine plus fluoxetine, and lithium combined with valproate or lamotrigine.
Antidepressants: the efficacy of antidepressants is not established in bipolar depression. If prescribing antidepressants, always do so in combination with an agent that has antimanic properties to limit the risk of affective instability or a switch to mania.
7 Summary of maintenance treatments
Considerations: facilitate engagement in treatment, assess for comorbidities, monitor side effects, provide education about illness, identify and check for early warning signs.
First-line treatments: lithium, lamotrigine, valproate and quetiapine.
Second-line treatments: olanzapine, aripiprazole and carbamazepine.
Inadequate response to treatment: seek consultation with a psychiatrist.
8 Rapid cycling and mixed episodes
During rapid cycling, individuals with bipolar disorder experience four or more mood episodes over a 12-month period, and some of these may be mixed episodes. A mixed episode is a period that lasts a week or more and satisfies criteria for both a manic and major depressive episode (except duration).
Abstract
Objective: To provide a practical overview of the pharmacological management of adults with bipolar disorder in primary care and the role of general practitioners in the pharmacotherapy of this complex disorder.
Data sources: Published guidelines for the treatment of bipolar disorder, plus Cochrane reviews, meta-analyses, review articles and reports from randomised controlled trials that were published up to May 2009.
Study selection: Over 500 articles on the treatment of bipolar disorder were reviewed, with an emphasis on meta-analyses and systematic reviews of randomised controlled trials. Where evidence was more limited, open trials and non-controlled data were also reviewed.
Data extraction: Key recommendations relevant to GPs were synthesised and rated according to National Health and Medical Research Council levels of evidence.
Data synthesis: Lithium, valproate and atypical antipsychotics are first-line treatment options for acute mania, and monotherapy is ideal if it produces an adequate response. For depressive episodes, recommendations are less definitive and the use of antidepressants is controversial. Most patients require maintenance treatment, during which pharmacotherapy should be used to prevent relapse, and psychological and social interventions should be considered.
Conclusions: Bipolar disorder is a lifelong episodic illness that affects 1%–2% of the population, many of whom are principally managed by their GPs. Pharmacological treatment with mood-stabilising agents is the primary form of management, although this is ideally provided in conjunction with psychosocial interventions.