Bipolar disorder therapeutics: maintenance treatment

Taiwan consensus on biological treatment of bipolar disorder during the acute, maintenance, and mixed phases: The 2022 update

BACKGROUND

Bipolar disorder is a mood dysregulation characterized by recurrent symptoms and episodes of mania, hypomania, depression, and mixed mood. The complexity of treating patients with bipolar disorder prompted the Taiwanese Society of Biological Psychiatry and Neuropsychopharmacology (TSBPN) to publish the first Taiwan consensus on pharmacological treatment of bipolar disorders in 2012. This paper presents the updated consensus, with changes in diagnostic criteria (i.e., mixed features) and emerging pharmacological evidence published up to April 2022.

METHODS

Our working group systemically reviewed the clinical research evidence and international guidelines and determined the levels of evidence for each pharmacological treatment on the basis of the most recent World Federation of Societies of Biological Psychiatry grading system. Four clinical-specific issues were proposed. The current TSBPN Bipolar Taskforce then discussed research evidence and clinical experience related to each treatment option in terms of efficacy and acceptability and then appraised final recommendation grades through anonymous voting.

RESULTS

In the updated consensus, we include the pharmacological recommendations for bipolar disorder with mixed features considering its high prevalence, the severe clinical prognosis, and the absence of approved medications. Cariprazine, lurasidone, repetitive transcranial magnetic stimulation, and ketamine are incorporated as treatment options. In the maintenance phase, the application of long-acting injectable antipsychotics is emphasized, and the hazards of using antidepressants and conventional antipsychotics are proposed.

CONCLUSIONS

This updated Taiwan consensus on pharmacological treatment for bipolar disorder provides concise evidence-based and empirical recommendations for clinical psychiatric practice. It may facilitate treatment outcome improvement in patients with bipolar disorder.

Antipsychotic use in Northern Italian inter-episode bipolar disorder patients: considering both second- and first-generation agents

Evidence supports increasing antipsychotic use in bipolar disorder, especially second-generation antipsychotics. However, data regarding first-generation antipsychotic contemporary use are limited. We studied 380 Northern Italian bipolar disorder inter-episode patients, grouped according to current antipsychotic use, stratified by bipolar subtype (BDI vs. BDII). Furthermore, we compared first-generation antipsychotic users vs. non-users. In our sample (n = 357), 81.8% were taking antipsychotics (74% second-generation antipsychotics, 24.1% first-generation antipsychotics), with antipsychotic use in BDI significantly more prevalent than in BDII (85.2% vs. 72.0%). Overall, antipsychotic users vs. non-users had higher rates of hypo/manic last episode, lifetime psychiatric hospitalization, psychosis, and current psychotropic use, but lower rates of anxiety disorder main comorbidity and current antidepressant use. First-generation antipsychotic use rates (30.3% in BDI vs. 6.5% in BDII) were associated with more frequently being unpartnered, having elevated first/last episodes, higher lifetime hospitalization, involuntary commitment, psychosis, and psychosocial rehabilitation rates, and more current psychotropic use, but lower Global Assessment Functioning scores and less current antidepressant use. Bipolar disorder patients had robust antipsychotic (second-generation antipsychotic > first-generation antipsychotic) use, consistently with previous reports. FGAs were still prescribed for a substantial group of patients, likely suffering from severe bipolar disorder. Prescriptions need to be monitored to assess their appropriateness and adherence to evidence-based recommendations.

Treatment and Prevention of Depression

Depression is one of the most common and debilitating psychiatric disorders and is a leading cause of suicide. Most people who become depressed will have multiple episodes, and some depressions are chronic. Persons with bipolar disorder will also have manic or hypomanic episodes. Given the recurrent nature of the disorder, it is important not just to treat the acute episode, but also to protect against its return and the onset of subsequent episodes.

Several types of interventions have been shown to be efficacious in treating depression. The antidepressant medications are relatively safe and work for many patients, but there is no evidence that they reduce risk of recurrence once their use is terminated. The different medication classes are roughly comparable in efficacy, although some are easier to tolerate than are others. About half of all patients will respond to a given medication, and many of those who do not will respond to some other agent or to a combination of medications. Electro-convulsive therapy is particularly effective for the most severe and resistant depressions, but raises concerns about possible deleterious effects on memory and cognition. It is rarely used until a number of different medications have been tried.

Although it is still unclear whether traditional psychodynamic approaches are effective in treating depression, interpersonal psychotherapy (IPT) has fared well in controlled comparisons with medications and other types of psychotherapies. It also appears to have a delayed effect that improves the quality of social relationships and interpersonal skills. It has been shown to reduce acute distress and to prevent relapse and recurrence so long as it is continued or maintained. Treatment combining IPT with medication retains the quick results of pharmacotherapy and the greater interpersonal breadth of IPT, as well as boosting response in patients who are otherwise more difficult to treat. The main problem is that IPT has only recently entered clinical practice and is not widely available to those in need.

Cognitive behavior therapy (CBT) also appears to be efficacious in treating depression, and recent studies suggest that it can work for even severe depressions in the hands of experienced therapists. Not only can CBT relieve acute distress, but it also appears to reduce risk for the return of symptoms as long as it is continued or maintained. Moreover, it appears to have an enduring effect that reduces risk for relapse or recurrence long after treatment is over. Combined treatment with medication and CBT appears to be as efficacious as treatment with medication alone and to retain the enduring effects of CBT. There also are indications that the same strategies used to reduce risk in psychiatric patients following successful treatment can be used to prevent the initial onset of depression in persons at risk. More purely behavioral interventions have been studied less than the cognitive therapies, but have performed well in recent trials and exhibit many of the benefits of cognitive therapy.

Mood stabilizers like lithium or the anticonvulsants form the core treatment for bipolar disorder, but there is a growing recognition that the outcomes produced by modern pharmacology are not sufficient. Both IPT and CBT show promise as adjuncts to medication with such patients. The same is true for family-focused therapy, which is designed to reduce interpersonal conflict in the family. Clearly, more needs to be done with respect to treatment of the bipolar disorders.

Good medical management of depression can be hard to find, and the empirically supported psychotherapies are still not widely practiced. As a consequence, many patients do not have access to adequate treatment. Moreover, not everyone responds to the existing interventions, and not enough is known about what to do for people who are not helped by treatment. Although great strides have been made over the past few decades, much remains to be done with respect to the treatment of depression and the bipolar disorders.

Medication-free Alternatives for Long-term Maintenance of Bipolar Disorder: A Case Series

Psychopharmacological treatment has been the mainstay in long-term maintenance of bipolar disorder (BD) patients for the last 60 years. Conventionally accepted treatment options are primarily based on expert opinion rather than on well-executed, independently funded research. Investigation of maintaining patients without medications using treatment alternatives has been neglected. This clinical case series examines the outcomes of 7 BD patients who experienced a poor response or significant side effects with conventional treatment modalities. Patients were gradually and safely withdrawn from all medications. Treatment strategies were based on an individualized holistic approach using herbs, nutritional supplements, vitamins, amino acids, acupuncture, dietary recommendations, and behavioral modifications. Multiple treatment modalities were combined addressing the etiological causes for BD symptoms. Upon withdrawal from psychotropic medications, patients were free of medication-induced side effects and obtained psychiatric stability for at least 10 months. Further research is needed to investigate the long-term outcomes of BD treatment modalities based on well-defined successful outcome criteria, such as reduction in symptoms, improvement in quality of life, overall health outcomes, and cost effectiveness.

A gene expression and systems pathway analysis of the effects of clozapine compared to haloperidol in the mouse brain implicates susceptibility genes for schizophrenia

Clozapine has markedly superior clinical properties compared to other antipsychotic drugs but the side effects of agranulocytosis, weight gain and diabetes limit its use. The reason why clozapine is more effective is not well understood. We studied messenger RNA (mRNA) gene expression in the mouse brain to identify pathways changed by clozapine compared to those changed by haloperidol so that we could identify which changes were specific to clozapine. Data interpretation was performed using an over-representation analysis (ORA) of gene ontology (GO), pathways and gene-by-gene differences. Clozapine significantly changed gene expression in pathways related to neuronal growth and differentiation to a greater extent than haloperidol; including the microtubule-associated protein kinase (MAPK) signalling and GO terms related to axonogenesis and neuroblast proliferation. Several genes implicated genetically or functionally in schizophrenia such as frizzled homolog 3 (FZD3), U2AF homology motif kinase 1 (UHMK1), pericentriolar material 1 (PCM1) and brain-derived neurotrophic factor (BDNF) were changed by clozapine but not by haloperidol. Furthermore, when compared to untreated controls clozapine specifically regulated transcripts related to the glutamate system, microtubule function, presynaptic proteins and pathways associated with synaptic transmission such as clathrin cage assembly. Compared to untreated controls haloperidol modulated expression of neurotoxic and apoptotic responses such as NF-kappa B and caspase pathways, whilst clozapine did not. Pathways involving lipid and carbohydrate metabolism and appetite regulation were also more affected by clozapine than by haloperidol.

Customization in prescribing for bipolar disorder

For many disorders, patient heterogeneity requires physicians to customize their treatment to each patient's needs. We test for the existence of customization in physicians' prescribing for bipolar disorder, using data from a naturalistic clinical effectiveness trial of bipolar disorder treatment (STEP-BD), which did not constrain physician prescribing. Multinomial logit is used to model the physician's choice among five combinations of drug classes. We find that our observed measure of the patient's clinical status played only a limited role in the choice among drug class combinations, even for conditions such as mania that are expected to affect class choice. However, treatment of a patient with given characteristics differed widely depending on which physician was seen. The explanatory power of the model was low. There was variation within each physician's prescribing, but the results do not suggest a high degree of customization in physicians' prescribing, based on our measure of clinical status.

Sleep deprivation in mood disorders

Growing clinical evidence in support of the efficacy and safety of sleep deprivation (SD), and its biological mechanisms of action suggest that this technique can now be included among the first-line antidepressant treatment strategies for mood disorders. SD targets the broadly defined depressive syndrome, and can be administered according to several different treatment schedules: total versus partial, single versus repeated, alone or combined with antidepressant drugs, mood stabilizers, or other chronotherapeutic techniques, such as light therapy and sleep phase advance. The present review focuses on clinical evidence about the place of SD in therapy, its indications, dosage and timing of the therapeutic wake, interactions with other treatments, precautions and contraindications, adverse reactions, mechanism of action, and comparative efficacy, with the aim of providing the clinical psychiatrist with an updated, concise guide to its application.

Effectiveness of psychotropic medications in the maintenance phase of bipolar disorder: a meta-analysis of randomized controlled trials

The purpose of this meta-analysis was to examine the efficacy of maintenance treatments for bipolar disorder. Placebo-controlled or active comparator bipolar maintenance clinical trials of ≥6 months' duration with at least 15 patients/treatment group were identified using Medline, EMBASE, clinicaltrials.gov, and Cochrane databases (1993 to July 2010). The main outcome measure was relative risk for relapse for patients in remission. Twenty trials (5,364 patients) were identified. Overall, lithium and quetiapine were the most studied agents (eight and five trials, respectively). The majority of studies included patients who had previously responded to treatment for an acute episode. All interventions, with the exception of perphenazine+mood stabilizer, showed a relative risk for manic/mixed or depressive relapse below 1.0, although there was variation in the statistical significance of the findings vs. placebo. No monotherapy was associated with a significantly reduced risk for both manic/mixed and depressed relapse. Of the combination treatments, only quetiapine+lithium/divalproex, was associated with a significantly reduced risk vs. comparator (placebo+lithium/valproate) for relapse at both the manic/mixed and depressed poles of bipolar illness. Limitations for the analysis include differences in study durations and definitions of relapse. In conclusion, available maintenance therapies show considerable variation in efficacy. The efficacy of lithium and divalproex has been confirmed, but newer therapies, such as a number of atypical antipsychotics were also shown to be effective in bipolar disorder. Efficacy of all maintenance interventions needs to be balanced against the safety and tolerability profiles of individual agents.

Aripiprazole in the maintenance treatment of bipolar disorder: a critical review of the evidence and its dissemination into the scientific literature

BACKGROUND

Aripiprazole, a second-generation antipsychotic medication, has been increasingly used in the maintenance treatment of bipolar disorder and received approval from the U.S. Food and Drug Administration for this indication in 2005. Given its widespread use, we sought to critically review the evidence supporting the use of aripiprazole in the maintenance treatment of bipolar disorder and examine how that evidence has been disseminated in the scientific literature.

METHODS AND FINDINGS

We systematically searched multiple databases to identify double-blind, randomized controlled trials of aripiprazole for the maintenance treatment of bipolar disorder while excluding other types of studies, such as open-label, acute, and adjunctive studies. We then used a citation search to identify articles that cited these trials and rated the quality of their citations. Our evidence search protocol identified only two publications, both describing the results of a single trial conducted by Keck et al., which met criteria for inclusion in this review. We describe four issues that limit the interpretation of that trial as supporting the use of aripiprazole for bipolar maintenance: (1) insufficient duration to demonstrate maintenance efficacy; (2) limited generalizability due to its enriched sample; (3) possible conflation of iatrogenic adverse effects of abrupt medication discontinuation with beneficial effects of treatment; and (4) a low overall completion rate. Our citation search protocol yielded 80 publications that cited the Keck et al. trial in discussing the use of aripiprazole for bipolar maintenance. Of these, only 24 (30%) mentioned adverse events reported and four (5%) mentioned study limitations.

CONCLUSIONS

A single trial by Keck et al. represents the entirety of the literature on the use of aripiprazole for the maintenance treatment of bipolar disorder. Although careful review identifies four critical limitations to the trial's interpretation and overall utility, the trial has been uncritically cited in the subsequent scientific literature. Please see later in the article for the Editors' Summary.

Risperidone long-acting injection as monotherapy and adjunctive therapy in the maintenance treatment of bipolar I disorder

IMPORTANCE OF THE FIELD

It is very rare for patients with bipolar disorder to have a single episode of mania or depression over a lifetime and the vast majority of these individuals need long-term prophylactic/maintenance treatment. However, treatment nonadherence is a major issue for close to half of subjects with bipolar disorder who are prescribed medications. Risperidone long-acting injection (LAI) has proven efficacious for the maintenance phase of bipolar disorder and may mitigate the problem of nonadherence in the substantial group of patients for whom this is a significant concern.

AREAS COVERED IN THIS REVIEW

This paper comprises a review and commentary regarding the use of risperidone LAI in bipolar disorder.

WHAT THE READER WILL GAIN

The reader will gain an understanding regarding the risks and benefits of risperidone LAI in bipolar disorder. We review the available evidence and discuss the strengths and weaknesses of published studies, providing an opinion about the clinical usefulness of risperidone LAI as well as suggestions for future research.

TAKE HOME MESSAGE

The use of risperidone LAI, through improved adherence, has the potential to ameliorate the course of bipolar disorder.

The use of triiodothyronine as an augmentation agent in treatment-resistant bipolar II and bipolar disorder NOS

BACKGROUND

Thyroid hormone plays a role in both serotonin and catecholamine functions in the brain, and has been linked to abnormal mood states in bipolar disorder. Unlike most studies which have included only patients with bipolar I, this study evaluated triiodothyronine (T3) as an augmentation agent for treatment-resistant depression in patients with bipolar II and bipolar disorder NOS.

METHODS

This study was a retrospective chart review of patients treated in a private clinic between 2002 and 2006. The charts of 125 patients with bipolar II disorder and 34 patients with bipolar disorder NOS were reviewed.

RESULTS

Patients had been unsuccessfully treated with an average of 14 other medications before starting T3. At an average dose of 90.4 mcg (range 13 mcg-188 mcg) the medication was well tolerated. None of the patients experienced a switch into hypomania, and only 16 discontinued due to side effects. Improvement was experienced by 84%, and 33% experienced full remission.

LIMITATIONS

The limitations are those associated with the retrospective chart review design.

CONCLUSIONS

A high percentage of bipolar II and bipolar NOS patients with treatment resistant depression improved on T3. Despite the use of higher than usual doses in many of the patients, the medication was well tolerated. Augmentation with supraphysiologic doses of T3 should be considered in cases of treatment resistant bipolar depression.

The relationship between antipsychotic medication adherence and patient outcomes among individuals diagnosed with bipolar disorder: a retrospective study

BACKGROUND

Reducing hospitalizations and emergency room visits is important to improve patient outcomes. This observational study examined the association between adherence to antipsychotics and risk of hospitalizations and emergency room (ER) visits among patients with bipolar disorder.

METHODS

Claims data from commercial healthcare plans (Pharmetrics; January 2000 to December 2006) for patients with bipolar disorder receiving an antipsychotic prescription were examined. Adherence was analyzed over a 12-month follow-up period after the receipt of first prescription of an antipsychotic. Adherence to antipsychotics was measured by the medication possession ratio (MPR). The MPR was calculated as the number of days that an antipsychotic medication was filled as compared with the total number of days during the follow-up period. Logistic stepwise regressions examined the association between achievement of various adherence goals and patient outcomes (hospitalization or ER visit for mental health or any reason).

RESULTS

In total, 7,769 patients with bipolar disorder were included. The mean MPR was 0.417, with 61.7% of individuals having an MPR < 0.50, and 78.7% an MPR < 0.75. As adherence improved, the risk of hospitalization or ER visit declined. A significant reduction in the risk of hospitalization (odds ratio (OR) 0.85, 95% confidence interval (CI) 0.75 to 0.98) or an ER visit (OR 0.84, 95% CI 0.74 to 0.96) for any cause was associated with an MPR >or= 0.75. An MPR >or= 0.80 was associated with a significant reduction in the risk of a mental health-related hospitalization (OR 0.82, 95% CI 0.70 to 0.95), while an MPR >or= 0.90 was associated with a significant reduction in risk of a mental health-related ER visit (OR 0.71, 95% CI 0.54 to 0.91).

CONCLUSION

Patients with lower antipsychotic adherence were at greater risk of hospitalizations and ER visits. Thus, any efforts to increase adherence, even in small increments, can be helpful in decreasing these risks.

Update on the treatment and management of schizophrenia and bipolar disorder

Schizophrenia and bipolar disorder are two debilitating mental health disorders, both of which manifest early in adulthood and are associated with severe impairment as well as increased suicide risk. In addition, factors affecting disease severity, such as substance abuse, are often prevalent in these patient populations. In the United States, the prevalence of bipolar disorder is believed to be approximately 3.5%, while the rate for schizophrenia is approximately 1%. Although each disorder presents with its own symptom profile, the approaches to treatment are similar and include early diagnosis and use of psychosocial therapy. Research initiatives, such as genetic studies, are used in both disorders as well. For schizophrenia, treatment typically includes the combination of an antipsychotic and psychosocial intervention. For bipolar disorder, clinicians commonly prescribe mood-stabilizing drugs (eg, lithium, valproic acid) as first-line treatment. Many of the second-generation antipsychotics have been approved by the US Food and Drug Administration for bipolar disorder treatment in the manic phase. Patients who are affected by either disorder also face the challenges of treatment nonadherence, which can be affected by substance abuse and can hinder symptom remission as well as spur unnecessary medication switches due to nonresponse. Family members play a key role in the treatment of either disorder. This expert review supplement focuses on treatment options and research strategies being utilized for the management and advanced understanding of schizophrenia and bipolar disorder. Research examining the pharmacology of commonly used medications for the treatment of both disorders is also presented.

Evolving trends in the long-term treatment of bipolar disorder

The episodic and chronic nature of bipolar disorder usually requires long-term treatment in all patients, yet there is an unmet need for well-tolerated and clinically effective maintenance therapy with enhanced patient adherence. Few well-tolerated treatment options are currently available that are both effective in all phases of bipolar disorder and prevent recurrence of episodes. Lithium has well-established efficacy in the prevention of further manic episodes and may also be effective in the prevention of depression and suicide, but safety is a concern due to narrow therapeutic window. For valproate and carbamazepine, data appear much less compelling. Lamotrigine has shown to be effective for long-term prevention of depressive episodes. Controlled studies suggest that atypical antipsychotics may also have mood-stabilizing properties and might become standard for long-term therapy in the new future. The role of psychoeducation in improving adherence to medication in long-term treatment and overall patient outcomes is also crucial.

Specificity of mood stabilizer action on neuronal growth cones

OBJECTIVES

Lithium, valproic acid (VPA) and carbamazepine (CBZ) are commonly used mood stabilizers, but their therapeutic mechanism is unclear. These drugs all cause the same morphological effects on postnatal rat neuronal dorsal root ganglia (DRG) growth cones via an inositol-reversible mechanism. However, due to limitations in earlier analysis, the effects of combining drugs, drug specificity and inositol stereoisomer specificity are unknown. We devised an improved analytical method to address these issues.

METHODS

Dorsal root ganglia explants were cultured individually and incubated with combinations of psychotropic drugs and inositol stereoisomers. We recorded axonal growth cone morphology and calculated growth cone area per a modified method described by Williams et al. (Nature 2002; 417: 292-295). Statistically significant changes in area were calculated using non-parametric statistical testing.

RESULTS

(i) Lithium and VPA showed an additive effect on growth cone spreading. (ii) Among eight additional psychotropic drugs to those previously tested, only imipramine and chlorpromazine altered DRG growth cone morphology. As this effect was not reversed by myo-inositol, it arises from a different mechanism to the mood stabilizers lithium, VPA and CBZ. (iii) Myo-inositol, but not scyllo- or epi-inositol, causes a significant reversal of the lithium effect on the growth cones spreading, consistent with the inositol depletion hypothesis.

CONCLUSIONS

These results show that lithium, VPA and CBZ are unique in causing altered neuronal morphology via myo-inositol depletion.

Bipolar depression: diagnostic and treatment considerations

Bipolar affective disorder is a recurrent, disabling, and potentially lethal illness that typically begins early in life. Although the disorder is defined by the manic and hypomanic episodes, for most people the depression episodes are the more virulent aspect of the illness. Specifically, the depressive episodes are more numerous, last longer, and are more difficult to treat than the manias, and depression is the principal cause of the illness's increased mortality due to suicide. For people with early-onset depression, predictors of subsequent bipolarity include a family history, psychotic features, and reverse neurovegetative features. Initial episodes of depression are commonly misdiagnosed, which often delays initiation of appropriate therapy and increases the likelihood of treatment with antidepressants alone. Unfortunately, the correct diagnosis is often not made until there has been a treatment-emergent affective switch. There are no treatments specifically approved for bipolar disorder in youth and, among antidepressants, only fluoxetine has received approved. When bipolarity is suspected, treatment with mood stabilizers, both conventional (i.e., lithium, valproate, and carbamazapine) and more recently classified (lamotrigine) and atypical antipsychotics should be prioritized. When antidepressants are indicated in combination with mood stabilizers, first choice options include bupropion and the selective serotonin reuptake inhibitors. Studies of adults indicate that several forms of focused psychotherapy may improve longer term outcomes.

Non-pharmacological treatments in the management of rapid cycling bipolar disorder

BACKGROUND

Rapid cycling (RC) bipolar disorder is often treatment-resistant to pharmacotherapy. Non-pharmacological methods, however, are reasonable considerations in treatment refractory cases of bipolar patients. Thus, such methods may be useful in the management of RC, especially when drugs are not shown to be effective.

METHOD

This review is based on studies of all major non-pharmacological methods which are used in the management of bipolar disorder, by focusing on data regarding patients with a RC pattern of the illness.

RESULTS

Regarding biological treatments, for electroconvulsive therapy and sleep deprivation, there exists some evidence that they might be efficacious in RC patients for acute treatment as well as for prophylaxis from recurrences. Light therapy has not been shown to be efficacious in RC, while no published data exist for transcranial magnetic stimulation and vagus nerve stimulation. The non-biological treatments include psychotherapeutic and psychosocial interventions; these have not been tried particularly on RC patients, but their use should be expected to contribute to the overall management of the RC pattern as it does to that of mood disorder in general.

LIMITATIONS

Many data on which this review is based are drawn from case reports or non-randomised trials.

CONCLUSIONS

Non-pharmacological methods, either biological or non-biological (psychotherapies and psychoeducation), may be applied in the management of RC patients. These methods might be used in combination with the administration of drug treatment, based on the clinical experience of the physician and the individual characteristics of the patient.

Pharmacotherapy of bipolar depression: an update

Bipolar affective disorder is a virulent illness with high rates of recurrence, disability, social impairment, and suicide. Although the manic or hypomanic episodes define the disorder, the depressions are more numerous and less responsive to treatment. As the initial depressive episodes are commonly misdiagnosed, initiation of therapy with mood stabilizers is often delayed, increasing the likelihood of treatment-emergent affective switches on antidepressant monotherapy. The empirical basis for selecting treatments for people with bipolar depression is weak, and only the combination of olanzapine and fluoxetine has received US Food and Drug Administration (FDA) approval. Conventional mood stabilizers are preferred for first-line therapies, although atypical antipsychotics are increasingly used, and FDA approval of quetiapine is pending. Antidepressants--particularly selective serotonin reuptake inhibitors and bupropion--are indicated when mood stabilizers are ineffective and for "breakthrough" depressions.

Do benzodiazepines extend the duration of follow-up treatment in patients with bipolar disorder?

INTRODUCTION

In patients with bipolar disorder, relapse and recurrence from the premature discontinuation of pharmacotherapy are serious clinical problems. Thus, clinicians must make every effort to ensure the sufficient duration of continual treatment even after the remission of acute episodes. Here, we examine whether there is any association between benzodiazepine (BZD) use and the duration of follow-up treatment in patients with bipolar disorder.

METHODS

The medical records of 70 bipolar patients hospitalized in a university hospital psychiatry ward were reviewed. Selected demographic and clinical variables, such as extent of BZD use and the total duration of outpatient follow-up treatment, were compared.

RESULTS

The duration of maintenance treatment at the outpatient department differed significantly between patients who were or were not given BZDs during admission (571 vs. 179 days) and after discharge (836 vs. 154 days). The variables that differed significantly between patients who received follow-up treatment for 6 or more months and those who did not was the number of days of BZD administration during admission (11 vs. 5 days) and after discharge (280 vs. 7 days), and years of education (11 vs. 13 years).

CONCLUSION

In the present study, BZDs are suggested as a possible adjunctive therapy for extending follow-up and thus preventing recurrence in patients with bipolar disorder.

Bipolar disorder: historic perspective, current pharmacologic treatment options and a review of quetiapine

Bipolar disorder is a complex mental illness that is frequently both under-diagnosed and under-treated. The symptoms of bipolar disorder can be confused with other medical illnesses or drug effects or may even be overlooked entirely as extreme character traits. The consequences of delayed diagnosis or misdiagnosis are potentially devastating, including loss of employment, impaired relationships and a severely impaired quality of life. This article will review the historic perspectives of bipolar disorder, the diagnostic criteria for the phases of the illness, and the pharmacologic options available to treat this condition. Quetiapine, an atypical antipsychotic, will be reviewed indepth. Based on extensive trial data, reviewed in this article, quetiapine is approved by the US Food and Drug Administration for use as monotherapy or as adjunctive therapy with other mood stabilizers for the treatment of acute manic episodes of bipolar I disorder. Clinical trials describing the efficacy of quetiapine in other phases of bipolar disorder and in other patient populations are also reviewed. A discussion of the drug profile of quetiapine includes its chemistry, availability, pharmacodynamics, pharmacokinetics and metabolism. Preclinical studies, postmarketing surveillance, safety, tolerability and regulatory issues are also evaluated. Finally, potential future directions for quetiapine are discussed, together with a review of key issues in bipolar disorder management and details of the information resources used in preparing this article.

Bipolar depression: issues in diagnosis and treatment

Although bipolar affective disorder is defined by the history of manic or hypomanic episodes, depression is arguably a more important facet of the illness. Depressive episodes, on average, are more numerous and last longer than manic or hypomanic episodes, and most suicides occur during these periods. Misdiagnosis of major depressive disorder delays initiation of appropriate therapy, further worsening prognosis. Distinguishing features of bipolar depression include earlier age of onset, a family history of bipolar disorder, presence of psychotic or reverse neurovegetative features, and antidepressant-induced switching. Bipolar I depressions should initially be treated with a mood stabilizer (carbamazapine, divalproex, lamotrigine, lithium, or an atypical antipsychotic); antidepressant monotherapy is contraindicated. More severe or "breakthrough" episodes often require a concomitant antidepressant, such as bupropion or a selective serotonin reuptake inhibitor (SSRI). The first treatment specifically approved for bipolar depression is a combination of the SSRI fluoxetine and the atypical antipsychotic olanzapine. For refractory depressive episodes, venlafaxine, the monoamine oxidase inhibitor tranylcypromine, and ECT are most widely recommended. The optimal duration of maintenance antidepressant therapy has not been established empirically and, until better evidence-based guidelines are established, should be determined on a case-by-case basis.

Comparison of fluoxetine, olanzapine, and combined fluoxetine plus olanzapine initial therapy of bipolar type I and type II major depression--lack of manic induction

OBJECTIVE

Current guidelines for the initial treatment of bipolar type I (BP I) and bipolar type II (BP II) major depressive episode (MDE) recommend avoiding the use of antidepressant drugs due to concerns over drug-induced manic switch episodes. However, recent evidence suggests that the manic switch rate during SSRI therapy of BP MDE may be lower than previously thought. This preliminary, placebo-controlled study examines the relative rates of treatment-emergent manic symptoms during fluoxetine monotherapy, olanzapine monotherapy, and combined fluoxetine plus olanzapine therapy of BP I and BP II MDE.

METHODS

32 BP I and 2 BP II MDE patients were randomized to receive double-blind therapy with fluoxetine monotherapy 10-30 mg daily, olanzapine monotherapy 5-20 mg daily, combined therapy with fluoxetine 10-40 mg plus olanzapine 5-15 mg daily, or placebo for up to 8 weeks. Outcome measures included the 17-item HAM-D, 17-item HAM-D "atypical" symptom profile (HAM-D 17-R), 28 item HAM-D, Montgomery-Asberg Depression Rating Scale (MADRS), and the Young Mania Rating (YMR) scale.

RESULTS

There were significant reductions over time in mean HAM-D 28 and MADRS ratings for all treatment groups (p<0.006). However, there were no differences among treatment conditions (p=ns). There was no significant increase in YMR scores over time in any treatment group. In contrast, there was a significant reduction in the mean YMR score in the fluoxetine-treated patients over time (p=0.008). No patient met DSM IV criteria for a manic episode.

LIMITATIONS

Cohort sizes were limited and the study was not powered to detect statistical differences in efficacy or mania symptoms among treatment conditions. The dose of fluoxetine was modest and the treatment duration was limited to 8 weeks.

CONCLUSION

These observations support earlier findings of a low manic switch rate during fluoxetine monotherapy of BP I and BP II MDE, and suggest that fluoxetine may be a safe initial treatment of BP MDE alone or in combination with olanzapine.

Open-label adjunctive topiramate in the treatment of unstable bipolar disorder

OBJECTIVE

To assess open-label adjunctive topiramate in the treatment of outpatients with unstable bipolar disorder (BD).

METHOD

Outpatients with DSM-IV-defined BD (I or II) exhibiting mood instability were enrolled in this 16-week, open-label, multicentre study. Topiramate was added to existing mood stabilizers and other psychotropic treatments. The primary effectiveness measure was the Clinical Global Impression of Severity (CGI-S) scale; other scales included the Young Mania Rating Scale (YMRS) and the Montgomery-Asberg Depression Rating Scale (MADRS). Safety assessments included monitoring adverse events, measuring tremor, monitoring vital signs and weight, and laboratory indices. We also evaluated patient satisfaction with treatment.

RESULTS

A total of 109 patients were enrolled. Intent-to-treat analysis showed significant improvement from baseline in the CGI-S, YMRS, and MADRS, starting at Week 2 (P < 0.001), with further accrual of benefit between Week 2 and Week 16 (P < 0.001). The mean modal dosage of topiramate during the stable dosing period was 180 mg daily. There was a mean 1.8 kg decrease in patient weight from topiramate initiation to Week 16 (P < 0.001). Topiramate was well tolerated by most patients; 11% withdrew from the study owing to adverse events. We noted a significant reduction in the mean severity score for preexisting tremor by Week 8 of treatment (P < 0.005); no notable changes in vital signs were observed. At Week 16, 50% of the patients were "completely satisfied" with topiramate treatment.

CONCLUSIONS

Adjunctive topiramate treatment can reduce the severity of manic and depressive symptoms, as well as reducing tremor and weight in outpatients with BD I or II.

Managing Bipolar Disorder in the Elderly

Clinical research in geriatric psychopharmacology has been a relatively neglected focus compared with the wealth of information on younger populations, and there is a dearth of published, controlled trials. Similarly, these are limited data in the area of geriatric bipolar disorder. Although there is an absence of rigorous, evidence-based information, preliminary data on older adults with bipolar disorder suggest some promising treatment options and important differences in older versus younger patients with bipolar illness. Lithium, while widely utilised in younger populations, is often poorly tolerated in the elderly. Clinical evidence regarding use of antiepileptic compounds in late-life bipolar disorder is generally compiled from bipolar disorder studies in mixed populations, studies in older adults with seizure disorders, and studies on dementia and psychotic conditions other than bipolar disorder. Valproate semisodium and carbamazepine are widely prescribed compounds in older adults with bipolar disorder. However, the popularity of these compounds has occurred in context of an absence of evidence-based data. The atypical antipsychotics have expanded the treatment armamentarium for bipolar disorder in mixed populations and may offer particular promise in management of bipolar illness in older populations as well. Olanzapine, risperidone, quetiapine, ziprasidone and aripiprazole are atypical antipsychotics that have been approved by the US FDA for the treatment of bipolar disorder; however, there are no published, controlled trials with atypical antipsychotics specific to mania in geriatric patients. Preliminary reports on the use of clozapine, risperidone, olanzapine and quetiapine suggest a role for the use of these agents in late-life bipolar disorder. Information with ziprasidone and aripiprazole specific to geriatric bipolar disorder is still lacking.

Use of polypharmacy and self-reported mood in outpatients with bipolar disorder

Objective. As polypharmacy is routinely used for the treatment of bipolar disorder, the relation between the daily number of psychotropic medications and self-reported mood was investigated. Method. Eighty patients (35 men and 45 women) with a diagnosis of bipolar disorder I or II, recruited from academic centres, entered their mood, sleep, and psychotropic medications for 3 months into ChronoRecord software. A total of 8662 days of data was received (mean 114.7 days/per patient). Results. Seventy-nine patients took a mean of 3.8 medications daily (SD 1.7; range 1-9); one took none. Of these patients, 73 (92.4%) took mood stabilizers, 47 (58.8%) took antidepressants, 31 (38.8%) took antipsychotics, 34 (42.5%) took benzodiazepines and 17 (21.1%) took thyroid hormones. Patients reporting normal mood more frequently took fewer medications; the Pearson correlation coefficient between the number of medications and the percent of days normal was -0.481 (P < 0.001). Grouping by number of medications, ANOVA analysis showed those taking fewer medications reported normal mood more frequently (P<0.001). Conclusion. Combination treatment regimens are routinely prescribed for bipolar disorder. Patients reporting normal mood more frequently took a fewer number of daily medications. Studies are needed to better identify those patients who would benefit from polypharmacy and to optimise the combinations of medications for patients with refractory disorder.

[Diagnosis and treatment of mixed states]

Mixed States are described in the literature using based on different definitions resulting in different descriptions of the clinical and demographic characteristics, of these episodes, but although they are always asdeemed a severe form of Bipolar disorder with worse prognosis and more prevalent than previously described. The aim of this article is to present a review of these different definitions and their impact on the study of mixed states. Pharmacological treatment is also discussed.

Rethinking the treatment paradigm for bipolar depression: the importance of long-term management

The need for long-term management of bipolar disorder is evident. Bipolar patients spend more time depressed than manic; however, few agents used for maintenance therapy of bipolar disorder have demonstrated good efficacy in delaying relapse into depression. This article provides a comprehensive review of open-label and randomized, controlled studies examining prophylactic efficacy in bipolar disorder, especially bipolar depression. Lithium, considered the gold standard for bipolar disorder maintenance therapy may be more effective in delaying manic relapse than in delaying depressive relapse. Evidence for the efficacy of divalproex and carbamazepine in delaying depressive relapse is yet to be fully elucidated. Lamotrigine has demonstrated efficacy in delaying time to depressive relapse. Unpublished studies show olanzapine's efficacy in preventing manic recurrence, while its efficacy in preventing depressive recurrence is yet to be proven. As patients with bipolar disorder are prone to experiencing depressive episodes, more attention needs to be focused on preventing depressive relapse. To date, three agents--lithium, lamotrigine, and olanzapine--have been shown to have prophylactic benefits in treating this highly recurrent disorder.

Treatment of non-schizophrenic disorders: focus on atypical antipsychotics

Antipsychotics are commonly used for conditions other than schizophrenia, yet support for such use in the literature is unclear. This article reviews the literature on the pharmacologic treatment of specific types of non-schizophrenic disorders: those associated with psychotic depression, obsessive-compulsive disorder, body dysmorphic disorder, bipolar disorder, and dementia. It focuses on the evidence for using antipsychotics in these conditions, placing emphasis on atypical antipsychotics. Medline/HealthStar and PsycInfo databases were used to identify published trials and reports of antipsychotics used specifically for non-schizophrenic disorders. Numerous studies were found supporting the use of atypical antipsychotics for non-schizophrenic disorders; however, with the exception of dementia, few randomized, double-blind controlled trials have been published examining the efficacy and safety of these agents in non-schizophrenic disorders. In general, most trials were restricted to short-term use as adjunctive therapy. The literature reviewed was primarily comprised of small open-label trials, thus making it difficult to draw definitive conclusions. Despite the limitations of the trials reviewed, atypical antipsychotics represent a promising treatment modality when considering their improved side effect profile compared to conventional agents. Appropriate dosing and the use of antipsychotics in combination with psychosocial treatments are important treatment considerations. Due to the frequent clinical use of atypical antipsychotics as adjunctive therapy, well-designed trials of these agents in non-schizophrenic disorders are necessary.

Avoiding drug-induced switching in patients with bipolar depression

Antidepressant-induced switching is a major risk during the treatment of bipolar depression. Despite several clinical studies, questions remain regarding both the definition of these mood switches and the most appropriate therapeutic strategy to avoid this adverse effect. This review will first briefly consider the current guidelines for the acute treatment of bipolar depression. We will then review the mechanisms of action of antidepressant and mood stabilisers, and the switches induced by various types of antidepressant treatments, or triggered by antidepressant withdrawal, as well as by atypical antipsychotics. We then will address the risk of mood switch according to the type of mood stabiliser used. The propensity to mood switches in bipolar patients is subject to individual differences. Therefore we will describe both the clinical and biological characteristics of patients prone to mood switches under antidepressant treatment. However, the clinical characteristics of the depressive syndrome may also be a key determinant for mood switches. Various data help identify the most appropriate drug management strategies for avoiding mood switches during the treatment of bipolar depression. Selective serotonin reuptake inhibitors appear to be the drugs of first-choice because of the low associated risk of mood switching. Antidepressants must be associated with a mood stabiliser and the most effective in the prevention of switches seems to be lithium. Whatever the mood stabiliser used, effective plasma levels must be ensured. The optimal duration of antidepressant treatment for bipolar depression is still an open issue - prolonged treatments after recovery may be unnecessary and may facilitate mood elation. Moreover, some mood episodes with mixed symptoms can be worsened by antidepressants pointing to the need for a better delineation of the categories of symptoms requiring antidepressant treatment. Finally, as a result of this review, we suggest some propositions to define drug-induced switches in bipolar patients, and to try to delineate which strategies should be recommended in clinical practice to reduce as far as possible the risk of mood switch during the treatment of bipolar depression.

Effects of chronic lithium and sodium valproate on concentrations of brain amino acids

The present study was designed to determine if the mood stabilizers, lithium and valproate, have common effects on concentrations of amino acid neurotransmitters which may be related to their mechanisms of action. Two separate groups of rats were administered therapeutic doses of lithium, sodium valproate, or saline for 2 weeks. Whole brain extracts were then examined using either high-field 1H NMR spectroscopy or HPLC. Both drugs decreased whole brain concentrations of aspartate, glutamate, and taurine while brain concentrations of gamma-aminobutyric acid (GABA) and alanine decreased following chronic sodium valproate administration but not following chronic lithium administration. These findings indicate that lithium and sodium valproate share common effects on the concentrations of certain amino acid neurotransmitters in whole brain which may be related to their mechanisms of action in bipolar disorder.

Alternatives to lithium and divalproex in the maintenance treatment of bipolar disorder

OBJECTIVES

The role of lithium carbonate in the maintenance treatment of bipolar disorder is well established. Unfortunately, many patients fail to respond adequately to this agent or are unable to tolerate its adverse effects. Divalproex has become a commonly used alternative to lithium, but it also is ineffective or poorly tolerated in many patients. This article attempts to review the available data on maintenance therapy in bipolar disorder with a variety of anticonvulsants and antipsychotics (both conventional and novel), with reference to relevant studies in acute mania and bipolar depression as well.

METHODS

Evidence on maintenance therapy and relevant acute-phase data were collected using MEDLINE database searches.

RESULTS

Data on maintenance therapy with agents other than lithium and divalproex are sparse, and often derived from open, uncontrolled studies. Implications and flaws of available data are discussed.

CONCLUSIONS

Other than lithium, there are few robust double-blind data to support the use of a variety of agents in the maintenance phase. However, uncontrolled data suggest that a number of agents merit further study.

The effect of lithium in bipolar disorder: a review of recent research evidence

Recently published clinical research on lithium is briefly reviewed. The antimanic effect of lithium is supported by recent evidence. It is confirmed that a drastic reduction of affective morbidity is very frequent in bipolar patients receiving lithium prophylaxis regularly for several years, but that the impact of prophylaxis on the course of bipolar disorder is significantly limited by the high drop-out rate. Lithium does seem to be efficacious also in bipolar disorder with mood-incongruent psychotic features or with rapid cycling. The effect of lithium prophylaxis does not seem to decrease over time, at least in the large majority of patients. The recurrence risk is increased in the months following lithium discontinuation. Lithium seems to exert an antisuicidal effect in bipolar patients.

The pharmacological treatment of bipolar affective disorder: practice is improving but could still be better

Pharmacological treatment of bipolar affective disorder was examined by case note review of 120 subjects under the care of four hospitals in the North-East of England and compared with that recommended in published consensus opinions and also with the findings of previous surveys. Although the only comparison available is with other geographical regions, it appears that lithium use has remained relatively constant in recent years (53% in this sample). The use of anticonvulsants (62%) was greater than in previous studies, as was use of mood stabilizers in combination (37% overall, 53% in rapid cycling subjects). Antidepressant use was found in 23% of subjects. Eleven percent of subjects taking antidepressants were not prescribed a mood stabilizer and 43% of antidepressants prescribed were tricyclics, possibly increasing the risk of switching to mania. Fifteen percent had no mood stabilizer and antipsychotic use was almost equally split between typical and atypical drugs. Practice in the population studied is nearer than treatment described in previous work to that suggested in the literature. This may result from either, or most probably a combination of, the local availability of a specialist mood disorder service and evolution of overall prescribing practice. However, it still falls short in a number of respects of such recommendations as exist and this requires further examination and monitoring.

Efficacy of atypical antipsychotics in mood disorders

Lithium and valproate are well recognized as mood-stabilizing medications. However, a significant number of patients with bipolar disorder do not respond to or cannot tolerate the side effects of these drugs. As a result, a search for safer and more effective mood stabilizers for the treatment of bipolar disorder is ongoing. Antipsychotic medications have long been used as adjunctive therapy in combination with mood-stabilizing medications. Although conventional neuroleptics (also known as typical antipsychotics) such as haloperidol or chlorpromazine are effective antimanic agents, they do not appear to have any efficacy in treating comorbid depressive symptoms. Furthermore, typical antipsychotics are associated with a number of well-known side effects, such as extrapyramidal symptoms and tardive dyskinesia. Mood-stabilizing effects have recently been reported for a number of newer "atypical" antipsychotics that have a broader spectrum of efficacy and better safety profiles than the typical antipsychotics. The results of several clinical trials suggest that atypical antipsychotics, including risperidone, olanzapine, ziprasidone, and quetiapine, are effective for the treatment of acute mania, and open-label studies suggest that atypical antipsychotics may have long-term mood-stabilizing effects.

Long-term therapy with lithium in a private practice clinic: a naturalistic study

OBJECTIVE

To document the effectiveness and vicissitudes of treating 14 bipolar patients with lithium carbonate over a combined 300 years, and an average of 21 years/patient.

METHODS

Chart review of the narrative and laboratory studies of these 14 patients ranging in duration from 12 to 29 years.

RESULTS

Lithium stabilized these bipolar patients over these periods. Only three patients required hospitalization, one because lithium was slowly tapered at her request after 6 years of mood stability, another because of non-compliance, and a third because of co-morbid alcohol abuse. One patient attempted suicide after lithium was tapered off. However, in some patients, there were serious side-effects necessitating lithium discontinuation.

CONCLUSIONS

Controlled studies in psychopharmacology are obviously preferred to open-label or naturalistic case studies. However, controlled studies are rarely conducted over long periods, and practice-related naturalistic research can be of value, albeit anecdotal and without the use of structured rating scales. In this paper, we are reporting on 14 patients seen consistently by one psychiatrist. These patients were functional and productive at work and in family life. The patients suffered brief hypomanic or depressive episodes. Although several patients experienced serious side-effects, lithium was continued with stable mood, while the side-effects were managed in collaboration with other specialists.

The Maudsley bipolar disorder project. A survey of psychotropic prescribing patterns in bipolar I disorder

OBJECTIVES

The outcome of Bipolar 1 Disorder (BD1) is greatly dependent on the adequacy and appropriateness of its treatment. As the treatment choices in BD1 disorder are increasing the aim of this study was to examine the current use of the pharmacological agents in BD1 patients and its association with clinical characteristics.

METHODS

Case note review of the pharmacotherapy of a sample of BD1 patients from a specified South London sector of a National Health Service Trust.

RESULTS

Half of the patients were on mood-stabilizers (usually lithium) and their use was associated with female gender and multiple admissions. Antipsychotics were more commonly used in patients with psychotic features and multiple manic episodes. Antidepressants were rarely prescribed alone and were not associated with increased number of manic episodes. Combination treatments were mostly used in patients in acute episodes and with multiple hospitalizations.

CONCLUSIONS

In ordinary care, the treatment of BD1 is often driven by symptoms and falls short of the existing practice guidelines.

Bipolar I disorder: psychopathology, medical management and dental implications

BACKGROUND

The authors review the clinical features, epidemiology, pathophysiology, medical management, dental findings and dental management of patients who have bipolar I disorder, or BD, previously known as manic-depressive disorder.

TYPES OF STUDIES REVIEWED

The authors conducted a MEDLINE search for the period 1995 through 2001 using the key terms "bipolar disorder," "epidemiology," "pathophysiology," "treatment" and "dentistry." The articles they selected for further review included those published in English in peer-reviewed journals; they gave preference to articles reporting randomized, controlled trials.

RESULTS

BD is a psychiatric illness characterized by extreme mood swings. Mania is accompanied by euphoria, grandiosity, racing thoughts and lack of insight. Depression is characterized by marked sadness or loss of interest or pleasure in daily activities. The unpredictable mood swings can distress the person, can impair social function and quality of life and are associated with a significant increase in the risk for substance abuse and suicide. BD is common in the United States, with a lifetime prevalence rate of 1.6 percent and recurrence rate of more than 50 percent.

CLINICAL IMPLICATIONS

The prevalence of dental disease usually is extensive because of poor oral hygiene and medication-induced xerostomia. Preventive dental education, saliva substitutes and anticaries agents are indicated. To avoid adverse drug interactions with the usually prescribed psychiatric medications, special precautions should be taken when administering certain antibiotics, analgesics and sedatives.

Changes in the molecular structure of the brain in bipolar disorder: findings using human postmortem brain tissue

Human postmortem brain studies are beginning to suggest mechanisms that underlie the pathology of bipolar disorder. Evidence that implicates abnormalities in G-protein, neurotransmitter turnover, neurotransmitter receptors and neurotransmitter receptor signal amplification will be reviewed. In addition, individual studies that suggest roles for pre-synaptic proteins, neuronal guidance proteins, neuropeptides, intra-neuronal ion homeostasis and environmental factor reactive proteins in the pathology of the disorder are also presented. Together these studies confirm that the pathology of bipolar disorder is complex but is yielding to intense study of the molecular architecture of postmortem brain tissue from subjects with the illness.

Clinical predictors of response to lamotrigine and gabapentin monotherapy in refractory affective disorders

BACKGROUND

The objective of the current study was to examine possible clinical predictors of positive response to lamotrigine or gabapentin monotherapy in treatment-refractory affectively ill patients.

METHODS

Forty-five patients with treatment refractory bipolar (n = 35) or unipolar (n = 10) affective disorder participated in a clinical study evaluating six weeks of treatment with lamotrigine, gabapentin, or placebo monotherapy given in a double-blind, randomized fashion with two subsequent cross-overs to the other agents. Patients received daily mood ratings and weekly cross-sectional scales. Much or very much improved on the Clinical Global Impression scale modified for bipolar illness was considered a positive response. Degree of response was correlated with a number of baseline demographic and course of illness variables in a univariate analysis and then by linear regression.

RESULTS

Response rates to lamotrigine (51%) exceeded those to gabapentin (28%) and placebo (21%). A positive response to lamotrigine monotherapy was associated with a bipolar diagnosis; fewer hospitalizations; fewer prior medication trials; and male gender (of which the latter two variables survived logistic regression). For gabapentin, degree of response correlated with shorter duration of illness; younger age; and lower baseline weight (with the latter two surviving linear regression).

CONCLUSIONS

In this highly treatment-refractory population, lamotrigine appeared most effective for male patients with fewer prior medication trials. Gabapentin monotherapy, although not better than placebo, appeared most effective in those with younger age and lower baseline weight. These preliminary data in a treatment refractory subgroup may help in the further definition of the range of clinical utility of these widely used anticonvulsants.

Emerging therapeutic targets in bipolar mood disorder

Bipolar mood disorder is a chronic, severe and life-threatening psychiatric illness, whose underlying pathophysiology is still obscure. Lithium is the mainstay of treatment for this illness, with robust acute antimanic and long-term prophylactic effects. Over the past decade, valproate has been another medication shown to have possibly similar mood-stabilising properties to lithium, in double-blind controlled trials. Nonetheless, among patients suffering from bipolar disorder, a substantial percentage appears to respond poorly to currently available pharmacological therapies, including lithium, valproate, carbamazepine and other newer compounds, clearly demonstrating that there is a substantial need for improved therapeutic agents. Very significant effort has been made in the past several years to elucidate the cellular mechanisms by which lithium and valproate produce their therapeutic effects. The available evidence points to a modulatory action of these compounds over multiple neural biochemical pathways and most investigations have found relevant actions of mood stabilisers on intracellular signal transduction mechanisms. Moreover, it has been shown in recent years that lithium and valproate lead to long-term changes in neural plasticity, with eventual neurotrophic and neuroprotective effects. Although these actions are not fully understood, stimulation of transcription factors and effects on gene expression are potentially involved. The search for the mechanisms of action of well-established mood-stabilisers has helped to reveal promising molecular targets to test novel therapeutic approaches. This review will examine the current investigations on the diverse biochemical and molecular pathways regulated by either lithium or valproate and highlight the potential cellular targets for the development of novel mood stabilisers.

Developments in mood stabilisers

Bipolar affective disorder is a life-long condition with profound effects on sufferers' social and occupational life. Despite efficacy in clinical trials and in some groups of patients, lithium's effectiveness in clinical practice is hampered by its side effect profile and limited concordance. Alternative and adjunctive treatments to lithium in bipolar disorder have been sought and the anticonvulsants carbamazepine and valproate show promise. Despite these advances, treatment resistance persists. Lamotrigine, a new anticonvulsant, is increasingly used in treatment-resistant cases under specialist supervision. Further pharmacological and non-pharmacological strategies for bipolar prophylaxis are currently under investigation. These developments are the focus of this review.

Bipolar depression: pharmacotherapy and related therapeutic strategies

The depressed phase of bipolar affective disorder is a significant cause of suffering, disability, and mortality and represents a major challenge to treating clinicians. This article first briefly reviews the phenomenology and clinical correlates of bipolar depression and then focuses on the major pharmacological treatment options. We strongly recommend use of mood stabilizers as the first-line treatment for the type I form of bipolar depression, largely because longer-term preventative therapy with these agents almost certainly will be indicated. Depressive episodes that do not respond to lithium, divalproex, or another mood stabilizer, or episodes that "breakthrough" despite preventive treatment, often warrant treatment with an antidepressant or electroconvulsive therapy. The necessity of mood stabilizers in the type II form of bipolar depression is less certain, aside from the rapid cycling presentation. Both experts and practicing clinicians recommend bupropion and the selective serotonin reuptake inhibitors as coequal initial choices, with venlafaxine and monoamine oxidase inhibitors, such as tranylcypromine, preferred for more resistant cases. The risk of antidepressant-induced hypomania or mania with concomitant mood stabilizer therapy is low, on the order of 5% to 10% during acute phase therapy. Additional therapeutic options and optimal durations of therapy also are discussed.