Mexiletine in treatment-resistant bipolar disorder

Challenges in defining treatment-resistant mania in adults: A systematic review

OBJECTIVES

To review the definitions of treatment-resistant mania (TRM) in the literature and propose criteria for an operationalized definition.

METHODS

A systematic search of five databases (MEDLINE, EMBASE, PsychInfo, Cochrane Central, and CINAHL) and data extraction of eligible articles.

RESULTS

In total, 47 articles addressing the concept of TRM were included, comprising 16 case reports, 11 case series, 3 randomized clinical trials, 8 open-label clinical trials, 1 experimental study, 7 narrative reviews, and 1 systematic review. While reviews discussed several challenges in defining TRM, definitions varied substantially based on different criteria for severity of mania, duration of mania, and use of specific therapeutic agents with minimal dosages and duration of treatment. Only a handful of the reviewed articles operationalized these criteria.

CONCLUSION

While the concept of TRM has been discussed in the literature for over three decades, we could not find an agreed-upon operationalized definition based on specific criteria. We propose and discuss a possible definition that could be used by clinicians to guide their practice and by researchers to assess the prevalence of TRM and develop and test interventions targeting TRM.

New "drugs and targets" in the GWAS era of bipolar disorder

OBJECTIVE

Due to the phenotypic heterogeneity and etiological complexity of bipolar disorder (BD), many patients do not respond well to the current medications, and developing novel effective treatment is necessary. Whether any BD genome-wide association study (GWAS) risk genes were targets of existing drugs or novel drugs that can be repurposed in the clinical treatment of BD is a hot topic in the GWAS era of BD.

METHODS

A list of 425 protein-coding BD risk genes was distilled through the BD GWAS, and 4479 protein-coding druggable targets were retrieved from the druggable genome. The overlapped genes/targets were subjected to further analyses in DrugBank, Pharos, and DGIdb datasets in terms of their FDA status, mechanism of action and primary indication, to identify their potential for repurposing.

RESULTS

We identified 58 BD GWAS risk genes grouped as the druggable targets, and several genes were given higher priority. These BD risk genes were targets of antipsychotics, antidepressants, antiepileptics, calcium channel antagonists, as well as anxiolytics and analgesics, either existing clinically-approved drugs for BD or the drugs than can be repurposed for treatment of BD in the future. Those genes were also likely relevant to BD pathophysiology, as many of them encode ion channel, ion transporter or neurotransmitter receptor, or the mice manipulating those genes are likely to mimic the phenotypes manifest in BD patients.

CONCLUSIONS

This study identifies several targets that may facilitate the discovery of novel treatments in BD, and implies the value of conducting GWAS into clinical translation.

The CINP Guidelines on the Definition and Evidence-Based Interventions for Treatment-Resistant Bipolar Disorder

BACKGROUND

Resistant bipolar disorder is a major mental health problem related to significant disability and overall cost. The aim of the current study was to perform a systematic review of the literature concerning (1) the definition of treatment resistance in bipolar disorder, (2) its clinical and (3) neurobiological correlates, and (4) the evidence-based treatment options for treatment-resistant bipolar disorder and for eventually developing guidelines for the treatment of this condition.

MATERIALS AND METHODS

The PRISMA method was used to identify all published papers relevant to the definition of treatment resistance in bipolar disorder and the associated evidence-based treatment options. The MEDLINE was searched to April 22, 2018.

RESULTS

Criteria were developed for the identification of resistance in bipolar disorder concerning all phases. The search of the literature identified all published studies concerning treatment options. The data were classified according to strength, and separate guidelines regarding resistant acute mania, acute bipolar depression, and the maintenance phase were developed.

DISCUSSION

The definition of resistance in bipolar disorder is by itself difficult due to the complexity of the clinical picture, course, and treatment options. The current guidelines are the first, to our knowledge, developed specifically for the treatment of resistant bipolar disorder patients, and they also include an operationalized definition of treatment resistance. They were based on a thorough and deep search of the literature and utilize as much as possible an evidence-based approach.

Canadian Network for Mood and Anxiety Treatments (CANMAT) and International Society for Bipolar Disorders (ISBD) 2018 guidelines for the management of patients with bipolar disorder

The Canadian Network for Mood and Anxiety Treatments (CANMAT) previously published treatment guidelines for bipolar disorder in 2005, along with international commentaries and subsequent updates in 2007, 2009, and 2013. The last two updates were published in collaboration with the International Society for Bipolar Disorders (ISBD). These 2018 CANMAT and ISBD Bipolar Treatment Guidelines represent the significant advances in the field since the last full edition was published in 2005, including updates to diagnosis and management as well as new research into pharmacological and psychological treatments. These advances have been translated into clear and easy to use recommendations for first, second, and third- line treatments, with consideration given to levels of evidence for efficacy, clinical support based on experience, and consensus ratings of safety, tolerability, and treatment-emergent switch risk. New to these guidelines, hierarchical rankings were created for first and second- line treatments recommended for acute mania, acute depression, and maintenance treatment in bipolar I disorder. Created by considering the impact of each treatment across all phases of illness, this hierarchy will further assist clinicians in making evidence-based treatment decisions. Lithium, quetiapine, divalproex, asenapine, aripiprazole, paliperidone, risperidone, and cariprazine alone or in combination are recommended as first-line treatments for acute mania. First-line options for bipolar I depression include quetiapine, lurasidone plus lithium or divalproex, lithium, lamotrigine, lurasidone, or adjunctive lamotrigine. While medications that have been shown to be effective for the acute phase should generally be continued for the maintenance phase in bipolar I disorder, there are some exceptions (such as with antidepressants); and available data suggest that lithium, quetiapine, divalproex, lamotrigine, asenapine, and aripiprazole monotherapy or combination treatments should be considered first-line for those initiating or switching treatment during the maintenance phase. In addition to addressing issues in bipolar I disorder, these guidelines also provide an overview of, and recommendations for, clinical management of bipolar II disorder, as well as advice on specific populations, such as women at various stages of the reproductive cycle, children and adolescents, and older adults. There are also discussions on the impact of specific psychiatric and medical comorbidities such as substance use, anxiety, and metabolic disorders. Finally, an overview of issues related to safety and monitoring is provided. The CANMAT and ISBD groups hope that these guidelines become a valuable tool for practitioners across the globe.

Safety and efficacy of olanzapine monotherapy in treatment-resistant bipolar mania: a 12-week open-label study

OBJECTIVE

To examine the safety and efficacy of olanzapine monotherapy in treatment-resistant bipolar mania.

METHOD

Subjects (n = 18) who were acutely manic, did not respond to lithium, anticonvulsants, and neuroleptics, and/or had intolerable side effects to them in previous manic episodes were openly treated with olanzapine monotherapy (5-40 mg/d) for 12 weeks. The primary and secondary outcomes included the change from baseline to endpoint in Young Mania Rating Scale (YMRS) total score, Clinical Global Impression for Bipolar Disorder-Severity Scale (CGI-S), 17-item Hamilton Depression Rating Scale (HAM-D) and Positive and Negative Syndrome Scale (PANSS), and response and remission rate.

RESULTS

The mean change in YMRS total score from baseline to endpoint was -23.3 ± 8.4 (p < 0.001). Fifteen (88.5%) patients achieved response (≥50% reduction in YMRS total score) and 14 (77.8%) achieved remission (YMRS total score ≤9 at endpoint). Mean changes from baseline to endpoint in CGI-S for mania and PANSS total score were significant, but not the changes in HAM-D total score or CGI-S for depression. The most common adverse events were sedation, self-reported weight gain, ≥7% increase in body weight, dizziness, and akathisia.

CONCLUSIONS

These preliminary results suggest that olanzapine monotherapy is effective and relatively safe in patients with treatment-resistant bipolar mania. Randomized, double-blind, placebo-controlled study is warranted.

Treatment-resistant bipolar disorder

Despite the remarkable increase in medications validated as effective in bipolar disorder, treatment is still plagued by inadequate response in acute manic or depressive episodes or in long-term preventive maintenance treatment. Established first-line treatments include lithium, valproate and second-generation antipsychotics (SGAs) in acute mania, and lithium and valproate as maintenance treatments. Recently validated treatments include extended release carbamazapine for acute mania and lamotrigine, olanzapine and aripiprazole as maintenance treatments. For treatment-resistant mania and as maintenance treatments, a number of newer anticonvulsants, and one older one, phenytoin, have shown some promise as effective. However, not all anticonvulsants are effective and each agent needs to be evaluated individually. Combining multiple agents is the most commonly used clinical strategy for treatment resistant bipolar patients despite a relative lack of data supporting its use, except for acute mania (for which lithium or valproate plus an SGA is optimal treatment). Other approaches that may be effective for treatment-resistant patients include high-dose thyroid augmentation, clozapine, calcium channel blockers and electroconvulsive therapy (ECT). Adjunctive psychotherapies show convincing efficacy using a variety of different techniques, most of which include substantial attention to education and enhancing coping strategies. Only recently, bipolar depression has become a topic of serious inquiry with the dominant controversy focusing on the place of antidepressants in the treatment of bipolar depression. Other than mood stabilizers alone or the combination of mood stabilizers and antidepressants, most of the approaches for treatment-resistant bipolar depression are relatively similar to those used in unipolar depression, with the possible exception of a more prominent place for SGAs, prescribed either alone or in combination with antidepressants. Future work in the area needs to explore the treatments commonly used by clinicians with inadequate research support, such as combination therapy and the use of antidepressants as both acute and adjunctive maintenance treatments for bipolar disorder.

Canadian Network for Mood and Anxiety Treatments (CANMAT) guidelines for the management of patients with bipolar disorder: consensus and controversies

Since the previous publication of Canadian Network for Mood and Anxiety Treatments (CANMAT) guidelines in 1997, there has been a substantial increase in evidence-based treatment options for bipolar disorder. The present guidelines review the new evidence and use criteria to rate strength of evidence and incorporate effectiveness, safety, and tolerability data to determine global clinical recommendations for treatment of various phases of bipolar disorder. The guidelines suggest that although pharmacotherapy forms the cornerstone of management, utilization of adjunctive psychosocial treatments and incorporation of chronic disease management model involving a healthcare team are required in providing optimal management for patients with bipolar disorder. Lithium, valproate and several atypical antipsychotics are first-line treatments for acute mania. Bipolar depression and mixed states are frequently associated with suicidal acts; therefore assessment for suicide should always be an integral part of managing any bipolar patient. Lithium, lamotrigine or various combinations of antidepressant and mood-stabilizing agents are first-line treatments for bipolar depression. First-line options in the maintenance treatment of bipolar disorder are lithium, lamotrigine, valproate and olanzapine. Historical and symptom profiles help with treatment selection. With the growing recognition of bipolar II disorders, it is anticipated that a larger body of evidence will become available to guide treatment of this common and disabling condition. These guidelines also discuss issues related to bipolar disorder in women and those with comorbidity and include a section on safety and monitoring.

Rapid cycling bipolar disorder: historical overview and focus on emerging treatments

OBJECTIVE

Rapid cycling bipolar disorder presents a significant challenge with respect to treatment. The cyclical nature of bipolar disorder has been well recognised for over a century, and following Dunner and Fieve's landmark paper in 1974, investigators have increasingly turned their attention to issues such as the definition of rapid cycling, demographic characterisation, treatment response and pharmacologic intervention.

METHODS

A literature search using Medline was performed, and selected articles which consider important developments in the definition, demographics and course of rapid cycling are reviewed. In addition, a systematic review of the literature published during the past 5 years (1999-2004) relating to treatment was conducted.

RESULTS

Relevant articles are reviewed.

CONCLUSIONS

This review highlights the important developments in our understanding of rapid cycling bipolar disorder, and focuses particularly on the recent literature regarding treatment.