The management of individuals with bipolar disorder: a review of the evidence and its integration into clinical practice

Lithium in Bipolar Disorder: Optimizing Therapy Using Prolonged-Release Formulations

Lithium has been a gold standard in the treatment of bipolar disorder (BD) for several decades. Despite a general reduction in the use of lithium over the past several years, it is effective in the management of both manic and depressive episodes in BD and continues to be recommended as a first-line mood stabilizer. This review provides an overview of the pharmacology of lithium and highlights its clinical profile in the management of BD, focusing on the potential advantages of prolonged-release (PR) versus immediate-release (IR) formulations of lithium. A literature search using PubMed was performed to identify articles describing IR and PR lithium in BD using specific search terms like ‘lithium’, ‘prolonged-release’, ‘sustained-release’, ‘extended-release’, ‘bipolar disorder’, ‘adherence’ and ‘compliance’. Relevant pharmacodynamic and pharmacokinetic data were also included. Several clinical trials suggested that lithium is effective in the treatment of acute mania and prophylaxis of BD and reduces the risk of suicide in patients with BD; it may also be used in combination with other drugs in the treatment of bipolar depression. Treatment with lithium must be monitored to avoid lithium-associated toxicity. The prolonged PR formulation of lithium has several advantages including consistent serum lithium concentrations, fewer adverse events and improved adherence to therapy. Although direct comparative studies between PR and IR formulations of lithium are primarily limited to pharmacokinetic studies, PR formulation of lithium provides potential advantages over IR formulation and can be effectively used in the management of BD with lesser adverse events.

Translational Significance of Selective Estrogen Receptor Modulators in Psychiatric Disorders

Accumulating data from various clinical trial studies suggests that adjuvant therapy with ovarian hormones (estrogens) could be effective in reducing cognitive deficit and psychopathological symptoms in women with psychiatric disorders. However, estrogen therapy poses serious limitations and health issues including feminization in men and increased risks of thromboembolism, hot flashes, breast hyperplasia, and endometrium hyperplasia when used for longer duration in older women (aged ≥ 60 years) or in women who have genetic predispositions. On the other hand, selective estrogen receptor modulators (SERMs), which may (or may not) carry some risks of hot flashes, thromboembolism, breast hyperplasia, and endometrial hyperplasia, are generally devoid of feminization effect. In clinical trial studies, adjuvant therapy with tamoxifen, a triphenylethylene class of SERM, has been found to reduce the frequency of manic episodes in patients with bipolar disorder, whereas addition of raloxifene, a benzothiophene class of SERM, to regular doses of antipsychotic drugs has been found to reduce cognitive deficit and psychological symptoms in men and women with schizophrenia, including women with treatment refractory psychosis. These outcomes together with potent neurocognitive, neuroprotective, and cardiometabolic properties suggest that SERMs could be the potential targets for designing effective and safer therapies for psychiatric disorders.

Application of induced pluripotent stem cells to understand neurobiological basis of bipolar disorder and schizophrenia

The etiology of neuropsychiatric disorders, such as schizophrenia and bipolar disorder, usually involves complex combinations of genetic defects/variations and environmental impacts, which hindered, for a long time, research efforts based on animal models and patients' non-neuronal cells or post-mortem tissues. However, the development of human induced pluripotent stem cell (iPSC) technology by the Yamanaka group was immediately applied to establish cell research models for neuronal disorders. Since then, techniques to achieve highly efficient differentiation of different types of neural cells following iPSC modeling have made much progress. The fast-growing iPSC and neural differentiation techniques have brought valuable insights into the pathology and neurobiology of neuropsychiatric disorders. In this article, we first review the application of iPSC technology in modeling neuronal disorders and discuss the progress in the accompanying neural differentiation. Then, we summarize the progress in iPSC-based research that has been accomplished so far regarding schizophrenia and bipolar disorder.

Future Directions for Pharmacotherapies for Treatment-resistant Bipolar Disorder

Current pharmacological treatments for bipolar disorder (BD) are limited and efficacy has historically been discovered through serendipity. There is now scope for new drug development, focused on the underlying biology of BD that is not targeted by current therapies. The need for novel treatments is urgent when considering treatment resistant BD, where current therapies have failed. While established drugs targeting the monoamine systems continue to be worthwhile, new biological targets including inflammatory and oxidative an nitrosative pathways, apoptotic and neurotrophic pathways, mitochondrial pathways, the N-methyl-Daspartate (NMDA)-receptor complex, the purinergic system, neuropeptide system, cholinergic system and melatonin pathways are all being identified as potential anchors for the discovery of new agents. Many agents are experimental and efficacy data is limited, however further investigation may provide a new line for drug discovery, previously stalled by lack of corporate interest.

Mood disorders: neurocognitive models

OBJECTIVES

In recent years, a number of neurocognitive models stemming from psychiatry and psychology schools of thought have conceptualized the pathophysiology of mood disorders in terms of dysfunctional neural mechanisms that underpin and drive neurocognitive processes. Though these models have been useful for advancing our theoretical understanding and facilitating important lines of research, translation of these models and their application within the clinical arena have been limited-partly because of lack of integration and synthesis. Cognitive neuroscience provides a novel perspective for understanding and modeling mood disorders. This selective review of influential neurocognitive models develops an integrative approach that can serve as a template for future research and the development of a clinically meaningful framework for investigating, diagnosing, and treating mood disorders.

METHODS

A selective literature search was conducted using PubMed and PsychINFO to identify prominent neurobiological and neurocognitive models of mood disorders.

RESULTS

Most models identify similar neural networks and brain regions and neuropsychological processes in the neurocognition of mood, however, they differ in terms of specific functions attached to neural processes and how these interact. Furthermore, cognitive biases, reward processing and motivation, rumination, and mood stability, which play significant roles in the manner in which attention, appraisal, and response processes are deployed in mood disorders, are not sufficiently integrated. The inclusion of interactions between these additional components enhances our understanding of the etiology and pathophysiology of mood disorders.

CONCLUSIONS

Through integration of key cognitive functions and understanding of how these interface with neural functioning within neurocognitive models of mood disorders, a framework for research can be created for translation to diagnosis and treatment of mood disorders.

Bridging the gap between education and appropriate use of benzodiazepines in psychiatric clinical practice

More than half a century after their discovery, benzodiazepines (BDZs) still represent one of the largest and most widely prescribed groups of psychotropic compounds, not only in clinical psychiatry but also in the entire medical field. Over the last two decades, however, there has been an increased focus on the development of antidepressants and antipsychotics on the part of the pharmaceutical industry, clinicians, and researchers, with a reduced interest in BDZs, in spite of their widespread clinical use. As a consequence, many psychiatric residents, medical students, nurses, and other mental health professionals might receive poor academic teaching and training regarding these agents, and have the false impression that BDZs represent an outdated chapter in clinical psychopharmacology. However, recent advances in the field, including findings concerning epidemiology, addiction risk, and drug interactions, as well as the introduction of the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition with related diagnostic changes, strongly encourage an updated appraisal of the use of BDZs in clinical practice. During a recent thematic event convened with the aim of approaching this topic in a critical manner, a group of young Italian psychiatrists attempted to highlight possible flaws in current teaching pathways, identify the main clinical pros and cons regarding current use of BDZs in clinical practice, and provide an updated overview of their use across specific clinical areas and patient populations. The main results are presented and discussed in this review.

A 2-year follow-up study of discharged psychiatric patients with bipolar disorder

This study investigated medication compliance, disease recurrence and the recovery of social function in discharged psychiatric patients with bipolar disorder. A 2-year follow-up was conducted on all patients with bipolar disorder, who were hospitalized in our psychiatric department between June 2010 and May 2011. Risk factors for recurrence were analyzed based on a self-designed questionnaire. Of the 252 patients in the study, 210 had complete information (83.3%) for the 2-year follow-up: 170 cases of bipolar I disorder and 40 cases of bipolar II disorder. The 1-year and 2-year full-compliance rates were 41.0% and 35.7%, respectively. The 1-year and 2-year recurrence rates were 42.4% and 61.0%, respectively. Statistically significant differences in rates were found between the bipolar subtypes for 1-year full compliance, 1-year non-compliance, 2-year recurrence, and 2-year readmission. Logistic regression identified different sets of independent variables that were risk factors for recurrence, and protective factors for recurrence at 1 year and 2 years after hospital discharge. The results of the follow-up indicated that the situation of patients with bipolar disorder after discharge is not optimistic, because of high recurrence rates, high non-compliance rates and low recovery rates. Clinical and social experts should pay more attention to the situation.

Physiological Correlates of Bipolar Spectrum Disorders and their Treatment

Bipolar spectrum disorders (BSDs) are associated with great personal and socioeconomic burden, with patients often facing a delay in detection, misdiagnosis when detected, and a trial-and-error approach to finding the most appropriate treatment. Therefore, improvement in the assessment and management of patients with BSDs is critical. Should valid physiological measures for BSDs be identified and implemented, significant clinical improvements are likely to be realized. This chapter reviews the physiological correlates of BSDs and treatment, and in doing so, examines the neuroimaging, electroencephalogram, and event-related potential, and peripheral physiological correlates that both characterize and differentiate BSDs and their response to treatment. Key correlates of BSDs involve underlying disturbances in prefrontal and limbic network neural activity, early neural processing, and within the autonomic nervous system. These changes appear to be mood-related and can be normalized with treatment. We adopt an "embodied" perspective and propose a novel, working framework that takes into account embodied psychophysiological mechanisms in which the physiological correlates of BSD are integrated. This approach may in time provide the objective physiological measures needed to improve assessment and decision making when treating patients with BSDs. Future research with integrative, multimodal measures is likely to yield potential applications for physiological measures of BSD that correlate closely with diagnosis and treatment.

Is bipolar disorder a risk factor for HIV infection?

HIV/AIDS is an extremely important public health challenge. Bipolar disorder spectrum has a significant prevalence, reported to be around 2.6%. This study analyses the relationship between sexual behaviors among MDQ positive and MDQ negative patients and its influence in HIV infection, and the impact of HIV diagnosis in both groups. Two hundred outpatients from a specialized clinic for HIV-care located in Walter Cantídio's University Hospital in Fortaleza, Brazil answered to a demographic questionnaire, the Mood Disorder Questionnaire (MDQ) and a sexual behavior questionnaire based on WHO's Behavioral Surveillance Surveys (BSS). Fifteen percent (N=30) of all HIV positive patients were MDQ+. The MDQ+ group was more likely to: be or have been married, have offspring, have sex with commercial and non-regular partners, have infrequent condom use with non-regular partners and of not have used condom in their first sex. Despite more sexual practices among MDQ+ patients before HIV diagnosis, these patients had a more significant reduction of all behaviors after HIV diagnosis than the MDQ- group.

Potential mechanisms of action of lithium in bipolar disorder. Current understanding

Lithium has been used for over half a century for the treatment of bipolar disorder as the archetypal mood stabilizer, and has a wealth of empirical evidence supporting its efficacy in this role. Despite this, the specific mechanisms by which lithium exerts its mood-stabilizing effects are not well understood. Given the inherently complex nature of the pathophysiology of bipolar disorder, this paper aims to capture what is known about the actions of lithium ranging from macroscopic changes in mood, cognition and brain structure, to its effects at the microscopic level on neurotransmission and intracellular and molecular pathways. A comprehensive literature search of databases including MEDLINE, EMBASE and PsycINFO was conducted using relevant keywords and the findings from the literature were then reviewed and synthesized. Numerous studies report that lithium is effective in the treatment of acute mania and for the long-term maintenance of mood and prophylaxis; in comparison, evidence for its efficacy in depression is modest. However, lithium possesses unique anti-suicidal properties that set it apart from other agents. With respect to cognition, studies suggest that lithium may reduce cognitive decline in patients; however, these findings require further investigation using both neuropsychological and functional neuroimaging probes. Interestingly, lithium appears to preserve or increase the volume of brain structures involved in emotional regulation such as the prefrontal cortex, hippocampus and amygdala, possibly reflecting its neuroprotective effects. At a neuronal level, lithium reduces excitatory (dopamine and glutamate) but increases inhibitory (GABA) neurotransmission; however, these broad effects are underpinned by complex neurotransmitter systems that strive to achieve homeostasis by way of compensatory changes. For example, at an intracellular and molecular level, lithium targets second-messenger systems that further modulate neurotransmission. For instance, the effects of lithium on the adenyl cyclase and phospho-inositide pathways, as well as protein kinase C, may serve to dampen excessive excitatory neurotransmission. In addition to these many putative mechanisms, it has also been proposed that the neuroprotective effects of lithium are key to its therapeutic actions. In this regard, lithium has been shown to reduce the oxidative stress that occurs with multiple episodes of mania and depression. Further, it increases protective proteins such as brain-derived neurotrophic factor and B-cell lymphoma 2, and reduces apoptotic processes through inhibition of glycogen synthase kinase 3 and autophagy. Overall, it is clear that the processes which underpin the therapeutic actions of lithium are sophisticated and most likely inter-related.

Quetiapine: a pharmacoeconomic review of its use in bipolar disorder

This article briefly summarizes the burden of bipolar disorder and the clinical profile of quetiapine (Seroquel®) in the management of bipolar disorder, followed by a detailed review of pharmacoeconomic analyses. Quetiapine is an atypical antipsychotic that is available in numerous countries as immediate-release and extended-release tablets for the treatment of major psychiatric disorders, including bipolar disorder. Randomized, double-blind, placebo-controlled trials with quetiapine have demonstrated its efficacy in bipolar I and II disorders, and the drug has been generally well tolerated in clinical trials. Three cost-effectiveness analyses of maintenance therapy in bipolar I disorder, which used similar Markov models and incorporated data from key clinical trials and a number of other sources, showed that quetiapine, as adjunctive therapy with mood stabilizers (lithium or divalproex), was a cost-effective treatment option from the healthcare payer perspective in the UK and the US. Quetiapine either dominated comparators (typically mood stabilizers alone) or was associated with incremental cost-effectiveness ratios that were usually well below widely accepted thresholds of cost effectiveness. One of the studies evaluated extended-release quetiapine, although clinical efficacy data used in the Markov model were for the immediate-release formulation. In another analysis, which used a discrete-event simulation model and was conducted from the perspective of the UK healthcare payer, quetiapine monotherapy was cost effective compared with olanzapine monotherapy as maintenance treatment for all phases of bipolar I or II disorder. In this model, favourable results were also shown for quetiapine (with or without mood stabilizers) compared with a wide range of maintenance therapy regimens. Another modelled analysis conducted from the UK healthcare payer perspective showed that quetiapine was dominated by haloperidol in the short-term treatment of a manic episode in patients with bipolar I disorder. Both favourable and unfavourable results have been reported in cost analyses of quetiapine in bipolar disorder (type I or type not specified). Possible explanations for some of the variability in results of the pharmacoeconomic analyses include heterogeneity among the models in terms of input parameters or assumptions in the base-case analyses, country- or region-specific differences in estimates of healthcare resource use and associated costs, variability in treatment alternatives, and differences in the year of costing and discounting used in the analyses. In addition, some of the studies had short time horizons and focused on acute manic episodes only, whereas others were longer-term analyses that considered the full spectrum of health states in patients with bipolar disorder. Various limitations of the studies have been recognized, and results from one country may not be applicable to other countries. In conclusion, results of available pharmacoeconomic analyses provide evidence of the cost effectiveness of quetiapine as an adjunct to mood stabilizers for maintenance therapy in (primarily type I) bipolar disorder from a healthcare payer perspective in the UK and the US. Some evidence is available to support the cost effectiveness of quetiapine monotherapy or the use of extended-release quetiapine as adjunctive therapy with mood stabilizers in this setting, although further analyses appear to be warranted. Whether these findings apply to other geographical regions requires further study. Evidence for the long-term (>2-year) cost effectiveness of quetiapine in bipolar disorder is currently limited and further studies are also needed to address the cost effectiveness of quetiapine from a societal perspective and in bipolar II disorder.

Mood-stabilizing drugs: mechanisms of action

Mood-stabilizing drugs are the most widely prescribed pharmacological treatments for bipolar disorder, a disease characterized by recurrent episodes of mania and depression. Despite extensive clinical utilization, significant questions concerning their mechanisms of action remain. In recent years, a diverse set of molecular and cellular targets of these drugs has been identified. Based on these findings, downstream effects on neural and synaptic plasticity within key circuits have been proposed. Here, we discuss recent data, identify current challenges impeding progress and define areas for future investigation. Further understanding of the primary targets and downstream levels of convergence of mood-stabilizing drugs will guide development of novel therapeutic strategies and help translate discoveries into more effective treatments with less burdensome adverse-effect profiles.

The increasing frequency of mania and bipolar disorder: causes and potential negative impacts

The frequency of mania has not changed during the last century even with the development of new diagnostic criteria sets. More specifically, from the mid-1970s to 2000, the rate of mania (variably labeled major affective disorder-bipolar disorder and bipolar I disorder) was consistently identified in US and international studies as ranging from 0.4% to 1.6%. By the late 1990s to the 2000s, the prevalence reported by some researchers for bipolar disorders (I and II and others) was in the 5% to 7% and higher ranges. The purpose of this paper was to review explanations for this change and the potentially negative impacts on the field.

Balanced efficacy, safety, and tolerability recommendations for the clinical management of bipolar disorder

OBJECTIVE

To provide practical and clinically meaningful treatment recommendations that amalgamate clinical experience and research findings for each phase of bipolar disorder.

METHODS

A comprehensive search of the literature was undertaken using electronic database search engines (Medline, PubMed, Cochrane reviews) using key words (e.g., bipolar depression, mania, treatment). All relevant randomised controlled trials were examined, along with review papers, meta-analyses, and book chapters known to the authors. In addition, the recommendations from accompanying papers in this supplement have been distilled and captured in the form of summary boxes. The findings, in conjunction with the clinical experience of international researchers and clinicians who are practiced in treating mood disorders, formed the basis of the treatment recommendations within this paper.

RESULTS

Balancing clinical experience with evidence informed and lead to the development of practical clinical recommendations that emphasise the importance of safety and tolerability alongside efficacy in the clinical management of bipolar disorder.

CONCLUSIONS

The current paper summarises the treatment recommendations relating to each phase of bipolar disorder while providing additional, evidence-based, practical insights. Medication-related side effects and monitoring strategies highlight the importance of safety and tolerability considerations, which, along with efficacy information, should be given equal merit.

The clinical management of bipolar disorder complexity using a stratified model

OBJECTIVE

To provide practical and clinically meaningful treatment recommendations that amalgamate clinical and research considerations for several common, and as yet understudied, bipolar disorder complex presentations, within the framework of a proposed stratified model.

METHODS

A comprehensive search of the literature was undertaken using electronic database search engines (Medline, PubMed, Web of Science) using key words (e.g., bipolar disorder, anxiety, rapid cycling, and subsyndromal). All relevant randomised controlled trials were examined, in addition to review papers, meta-analyses, and book chapters known to the authors. The findings formed the basis of the treatment recommendations within this paper.

RESULTS

In light of the many broad presentations of bipolar disorder, a stratified model of bipolar disorder complexity was developed to facilitate consideration of the myriad of complexities that can occur during the longitudinal course of illness and the appropriate selection of treatment. Evidence-based treatment recommendations are provided for the following bipolar disorder presentations: bipolar II disorder, subsyndromal symptoms, mixed states, rapid cycling, comorbid anxiety, comorbid substance abuse, and for the following special populations: young, elderly, and bipolar disorder around the time of pregnancy and birth. In addition, some key strategies for countering treatment non-response and alternative medication recommendations are provided.

CONCLUSIONS

Treatment recommendations for the more challenging presentations of bipolar disorder have historically received less attention, despite their prevalence. This review acknowledges the weaknesses in the current evidence base on which treatment recommendations are generally formulated, and additionally emphasises the need for high-quality research in this area. The stratified model provides a means for conceptualizing the complexity of many bipolar disorder presentations and considering their management.

The role of alprazolam for the treatment of panic disorder in Australia

OBJECTIVE

To investigate the potential impact of increasing prescription rates of alprazolam for the treatment of panic disorder (PD) in Australia through a review of efficacy, tolerability and adverse outcome literature.

METHODS

Data were sourced by a literature search using MEDLINE, Embase, PsycINFO and a manual search of scientific journals to identify relevant articles. Clinical practice guidelines from the American Psychiatric Association, National Institute of Clinical Excellence, Royal Australian and New Zealand College of Psychiatrists and World Federation of Societies of Biological Psychiatry were sourced. Prescription data were sourced from Australian governmental sources.

RESULTS

Alprazolam has shown efficacy for control of PD symptoms, particularly in short-term controlled clinical trials, but is no longer recommended as a first-line pharmacological treatment due to concerns about the risks of developing tolerance, dependence and abuse potential. Almost no evidence is available comparing alprazolam to current first-line pharmacological treatment. Despite this, prescription rates are increasing. A number of potential issues including use in overdose and impact on car accidents are noted. conclusion: Although effective for PD symptoms in clinical trials, a number of potential issues may exist with use. Consideration of its future place in PD treatment in Australia may be warranted.

The science and practice of lithium therapy

INTRODUCTION

Despite more that 60 years of clinical experience, the effective use of lithium for the treatment of mood disorder, in particular bipolarity, is in danger of becoming obsolete. In part, this is because of exaggerated fears surrounding lithium toxicity, acute and long-term tolerability and the encumbrance of life-long plasma monitoring. Recent research has once again positioned lithium centre stage and amplified the importance of understanding its science and how this translates to clinical practice.

OBJECTIVE

The aim of this paper is to provide a sound knowledge base as regards the science and practice of lithium therapy.

METHOD

A comprehensive literature search using electronic databases was conducted along with a detailed review of articles known to the authors pertaining to the use of lithium. Studies were limited to English publications and those dealing with the management of psychiatric disorders in humans. The literature was synthesized and organized according to relevance to clinical practice and understanding.

RESULTS

Lithium has simple pharmacokinetics that require regular dosing and monitoring. Its mechanisms of action are complex and its effects are multi-faceted, extending beyond mood stability to neuroprotective and anti-suicidal properties. Its use in bipolar disorder is under-appreciated, particularly as it has the best evidence for prophylaxis, qualifying it perhaps as the only true mood stabilizer currently available. In practice, its risks and tolerability are exaggerated and can be readily minimized with knowledge of its clinical profile and judicious application.

CONCLUSION

Lithium is a safe and effective agent that should, whenever indicated, be used first-line for the treatment of bipolar disorder. A better understanding of its science alongside strategic management of its plasma levels will ensure both wider utility and improved outcomes.

Maintenance Treatment of Bipolar Disorder with Ziprasidone in Adjunctive Use with Lithium or Valproate

Ziprasidone is a second generation (“atypical”) antipsychotic drug that has been used alone and as an adjunct to standard mood stabilizers to reduce recurrence rates in bipolar disorder. Approval of ziprasidone as an adjunct to lithium or valproate in 2009 was based on an industry sponsored study of 584 outpatients with a current or recent manic episode; 240 of these subjects were randomized to adjunctive ziprasidone or placebo and 138 completed a six month trial. Patients enrolled in maintenance studies did not have refractory mood disorders, comorbid conditions or risk of dangerousness. Maintenance ziprasidone augmentation is an option for patients who do not respond to a single mood stabilizer rapidly, and possibly for those with residual psychotic symptoms, but there are insufficient data to prefer this approach to combinations of mood stabilizers or augmentation with other agents. Ziprasidone is generally well tolerated, with less sedation and weight gain than many other antipsychotic drugs; it should be taken with food. Primary interactions of concern are with other serotonergic medications, MAO inhibitors, and other medications that prolong the QT interval.

The lithiumeter: a measured approach

BACKGROUND

Lithium has long been recognised for its mood-stabilizing effects in the management of bipolar disorder (BD) but in practice its use has been limited because of real and 'imagined' concerns. This article addresses the need for lithium to be measured with respect to its clinical and functional effects. It introduces a visual scale, termed lithiumeter, which captures the optimal lithium plasma levels for the treatment of BD.

METHODS

  Key words pertaining to lithium's administration, dosing, and side effects as well as its efficacy in acute and long-term treatment of BD were used to conduct an electronic search of the literature. Relevant articles were identified by the authors and reviewed.

RESULTS

This paper outlines the considerations necessary prior to initiating lithium therapy and provides a guide to monitoring lithium plasma levels. Current recommendations for optimal plasma lithium levels in the management of BD are then discussed with respect to indications for use in the acute phases of the illness and maintenance therapy. The risks associated with lithium treatment are also discussed.

CONCLUSIONS

The lithiumeter provides a practical guide of optimal lithium levels for the clinical management of BD.

Optimal frequency of lithium administration in the treatment of bipolar disorder: clinical and dosing considerations

Bipolar disorder is a recurrent chronic illness distinguished by periods of mania and depression. Lithium has been used for about 60 years as a 'mood stabilizer' for bipolar disorder with proven efficacy in preventing relapse of both mania and depression. Despite its long history and ongoing use in current management of bipolar disorder, the optimal dosing of lithium is still the subject of ongoing debate. This article aims to evaluate different dosing schedules, in the light of the unique pharmacokinetic and pharmacodynamic properties of lithium, as well as its adverse-effect and toxicity profiles. This is all the more important given the narrow therapeutic index of lithium. Current recommendations mostly advocate that lithium be administered in multiple daily doses. However, single daily or alternate daily schedules may be viable options for administration. Multiple daily schedules are thought to be advantageous in maintaining more constant plasma lithium concentrations than single daily regimens, which are associated with significant fluctuations throughout the day. When comparing these two schedules with respect to plasma lithium concentrations, adverse-effect profiles and recurrence of symptoms, there are no significant differences between the two regimens. In fact, a single daily regimen may have added advantages in reducing the risk of long-term renal damage and increasing compliance. The evidence for alternate daily dosing is somewhat varied with regard to symptom recurrence; however, this schedule has been shown to be associated with decreased adverse effects, and further research into this issue is therefore warranted. Presently, therefore, clinicians should consider single daily administration of lithium to potentially minimize adverse effects and enhance compliance.

Does stage of illness impact treatment response in bipolar disorder? Empirical treatment data and their implication for the staging model and early intervention

OBJECTIVE

The staging model suggests that early stages of bipolar disorder respond better to treatments and have a more favourable prognosis. This study aims to provide empirical support for the model, and the allied construct of early intervention.

METHODS

Pooled data from mania, depression, and maintenance studies of olanzapine were analyzed. Individuals were categorized as having had 0, 1-5, 6-10, or >10 prior episodes of illness, and data were analyzed across these groups.

RESULTS

Response rates for the mania and maintenance studies ranged from 52-69% and 10-50%, respectively, for individuals with 1-5 previous episodes, and from 29-59% and 11-40% for individuals with >5 previous episodes. These rates were significantly higher for the 1-5 group on most measures of response with up to a twofold increase in the chance of responding for those with fewer previous episodes. For the depression studies, response rates were significantly higher for the 1-5 group for two measures only. In the maintenance studies, the chance of relapse to either mania or depression was reduced by 40-60% for those who had experienced 1-5 episodes or 6-10 episodes compared to the >10 episode group, respectively. This trend was statistically significant only for relapse into mania for the 1-5 episode group (p=0.005).

CONCLUSION

Those individuals at the earliest stages of illness consistently had a more favourable response to treatment. This is consistent with the staging model and underscores the need to support a policy of early intervention.

The role of Wnt signaling and its interaction with diverse mechanisms of cellular apoptosis in the pathophysiology of bipolar disorder

The neurobiology of Bipolar Disorder (BD) is not completely understood, although abnormalities in neuroplasticity and control of apoptosis have been considered as central events in its pathophysiology. The molecules of the Wnt family comprise a class of proteins that control essential developmental processes such as embryonic patterning, cell growth, migration, and differentiation with their actions largely exerted by modulating gene transcription. The Wnt signaling pathway has interface with some mediators with a well documented action in neuroplasticity and regulation of cell surviving. In addition, mood stabilizers such as lithium and valproate may have their neuroprotective properties in part mediated by the Wnt pathway. This article is an overview of how the Wnt signaling cascade might be involved in the pathogenesis of BD and also in details of intracellular events related to this pathway. Further studies of Wnt signaling may lead to a better comprehension of the neuroprotective actions of mood stabilizers and contribute to improving the therapeutics of BD.

The pharmacological treatment of bipolar disorder: the question of modern advances

INTRODUCTION

Lithium has been the mainstay of treatment for patients with bipolar disorder in the United States since 1970. Major treatment guidelines recommend lithium as a first-line treatment for mania and maintenance treatment of bipolar disorder, yet lithium has fallen out of favor while other agents have grown in popularity. The purpose of this review is to examine the evidence for treatments that were available in 1970 and to determine if the field has made any significant advance in the treatment of mania, bipolar depression, and maintenance.

METHODS

We conducted a MEDLINE search through 2009, and examined only English-language, randomized/controlled, placebo, or comparison studies. Tolerability as a factor was not considered for this review.

RESULTS

Lithium, valproate, benzodiazepines, and antipsychotics have been reported effective for mania-which was essentially the state of the field in 1970. Despite an FDA indication for the use of lamotrigine for depression and depression maintenance, the supporting evidence is conflicting. For bipolar maintenance, the evidence is overwhelming in support of lithium and very thin for valproate and carbamazepine. There is emerging evidence that several atypical antipsychotics may have efficacy in prevention.

DISCUSSION

The gold standard for treating bipolar disorder in 1970 was lithium, and the gold standard in 2009 remains lithium. Newer agents may increase our armamentarium to some extent, but it is not clear if they represent a major advance in treatment. They still need to be tested against the gold standard.

Risperidone long-acting injection: in bipolar I disorder

A long-acting intramuscular formulation of the atypical antipsychotic agent risperidone is now indicated for the maintenance treatment of patients with bipolar I disorder. The formulation utilizes a novel drug delivery system of biodegradable microspheres and is bioequivalent to the oral formulation of the drug. Moreover, fluctuations in plasma drug concentrations at steady state were 1.7-fold lower with long-acting than with oral risperidone. Maintenance treatment with risperidone long-acting injection, as monotherapy in adults with stabilized bipolar I disorder or as an adjunct to standard therapy in adults with stabilized, frequently relapsing bipolar I disorder, was effective in delaying relapse to symptoms in two well designed trials with maintenance phases of 1 or 2 years' duration. The time to relapse to any mood episode (primary endpoint) was significantly longer with risperidone long-acting injection than with placebo in both studies. Risperidone long-acting injection also significantly reduced the risk of relapse relative to placebo in these trials. Maintenance treatment with risperidone long-acting injection was generally well tolerated in patients with bipolar disorder, both as monotherapy and adjunctive therapy, with most adverse reactions being of mild to moderate severity.

The neuropeptide VGF is reduced in human bipolar postmortem brain and contributes to some of the behavioral and molecular effects of lithium

Recent studies demonstrate that the neuropeptide VGF (nonacronymic) is regulated in the hippocampus by antidepressant therapies and animal models of depression and that acute VGF treatment has antidepressant-like activity in animal paradigms. However, the role of VGF in human psychiatric disorders is unknown. We now demonstrate using in situ hybridization that VGF is downregulated in bipolar disorder in the CA region of the hippocampus and Brodmann's area 9 of the prefrontal cortex. The mechanism of VGF in relation to LiCl was explored. Both LiCl intraperitoneally and VGF intracerebroventricularly reduced latency to drink in novelty-induced hypophagia, and LiCl was not effective in VGF(+/-) mice, suggesting that VGF may contribute to the effects of LiCl in this behavioral procedure that responds to chronic antidepressant treatment. VGF by intrahippocampal injection also had novel activity in an amphetamine-induced hyperlocomotion assay, thus mimicking the actions of LiCl injected intraperitoneally in a system that phenocopies manic-like behavior. Moreover, VGF(+/-) mice exhibited increased locomotion after amphetamine treatment and did not respond to LiCl, suggesting that VGF is required for the effects of LiCl in curbing the response to amphetamine. Finally, VGF delivered intracerebroventricularly in vivo activated the same signaling pathways as LiCl and is necessary for the induction of mitogen-activated protein kinase and Akt by LiCl, thus lending insight into the molecular mechanisms underlying the actions of VGF. The dysregulation of VGF in bipolar disorder as well as the behavioral effects of the neuropeptide similar to LiCl suggests that VGF may underlie the pathophysiology of bipolar disorder.