Pharmacologic treatment of rapid cycling and mixed states in bipolar disorder: an argument for the use of lithium

Role of adjunctive nonpharmacological strategies for treatment of rapid-cycling bipolar disorder

Rapid-cycling bipolar disorder (RCBD) is a phase of bipolar disorder defined by the presence of ≥ 4 mood episodes in a year. It is a common phenomenon characterized by greater severity, a predominance of depression, higher levels of disability, and poorer overall outcomes. It is resistant to treatment by conventional pharmacotherapy. The existing literature underlines the scarcity of evi-dence and the gaps in knowledge about the optimal treatment strategies for RCBD. However, most reviews have considered only pharmacological treatment options for RCBD. Given the treatment-refractory nature of RCBD, nonpharmacological interventions could augment medications but have not been adequately examined. This review carried out an updated and comprehensive search for evidence regarding the role of nonpharmacological therapies as adjuncts to medications in RCBD. We identified 83 reviews and meta-analyses concerning the treatment of RCBD. Additionally, we found 42 reports on adjunctive nonpharmacological treatments in RCBD. Most of the evidence favoured concomitant electroconvulsive therapy as an acute and maintenance treatment. There was pre-liminary evidence to suggest that chronotherapeutic treatments can provide better outcomes when combined with medications. The research on adjunctive psychotherapy was particularly scarce but suggested that psychoeducation, cognitive behavioural therapy, family interventions, and supportive psychotherapy may be helpful. The overall quality of evidence was poor and suffered from several methodological shortcomings. There is a need for more methodologically sound research in this area, although clinicians can use the existing evidence to select and individualize nonpharmacological treatment options for better management of RCBD. Patient summaries are included to highlight some of the issues concerning the implementation of adjunctive nonpharmacological treatments.

Clinical correlates of DSM-5 mixed features in bipolar disorder: A meta-analysis

BACKGROUND

Systematic data on clinical correlates of mixed features in bipolar disorder are not available, so far. We conducted a systematic review and meta-analysis estimating the association between DSM-5 mixed features and candidate characteristics in depressive and manic/hypomanic episodes.

METHODS

We included observational studies indexed in the main electronic databases. The association between DSM-5 mixed features and relevant correlates was estimated using odds ratio (OR) and standardized mean difference (SMD) with 95% confidence intervals (CIs), for categorical and continuous variables, respectively. Analyses were based on random effects models.

RESULTS

Eight studies were included, involving 3070 individuals (1495 with a major depressive episode and 1575 with hypo/manic episode). No clinical characteristics were associated with mixed features in subjects with a depressive episode. Among subjects with a manic/hypomanic episode, those with mixed features were more likely to have a history of suicide attempts (OR: 2.37; 95%CI: 1.42 to 3.94; I²=39.7%), co-occurring anxiety disorders (OR: 2.67; 95%CI: 1.28 to 5.57; I²=0%), and a rapid cycling course (OR=4.23; 95%CI: 1.29 to 13.81; I²=0%), with less severe manic symptoms (SMD=-0.40; 95%CI: -0.65 to -0.16; I²=0%).

LIMITATIONS

(1) the heterogeneity of methods across studies and the inconsistency of findings; (2) the limited amount of data on correlates of DSM-5 mixed features; (3) the possible influence of publication bias.

CONCLUSIONS

Findings of this meta-analysis show that mixed features among individuals with a manic/hypomanic episode may identify a special clinical population, characterized not only by depressive symptoms, but also by anxiety, rapid cycling, and suicidality.

The use of lithium in mixed states

Lithium is a unique drug. In more than 60 years of observation, it showed its multiple important clinical properties in treating mania, stabilizing mood alterations, preventing suicide and protecting from neurodegeneration. It was also the most extensively studied drug in psychiatry. Nevertheless, it is generally underprescribed. Specifically, lithium is virtually not considered in the treatment of patients affected by mixed affective states. Lithium is not suggested for the acute treatment of mixed affective states and is considered to be less effective than other mood stabilizers in the long-term management of these patients. The main reason why lithium has no indication for mixed states is the "lack of evidence." Actually, there are several reasons to consider lithium as an effective treatment in patients with mixed affective states.

The Diagnosis and Management of Bipolar I and II Disorders: Clinical Practice Update

Bipolar disorders, including bipolar I disorder (BP-I) and bipolar II disorder (BP-II), are common, potentially disabling, and, in some cases, life-threatening conditions. Bipolar disorders are characterized by alternating episodes of mania or hypomania and depression, or mixtures of manic and depressive features. Bipolar disorders present many diagnostic and therapeutic challenges for busy clinicians. Adequate management of bipolar disorders requires pharmacotherapy and psychosocial interventions targeted to the specific phases of illness. Effective treatments are available for each illness phase, but mood episode relapses and incomplete responses to treatment are common, especially for the depressive phase. Mood symptoms, psychosocial functioning, and suicide risk must, therefore, be continually reevaluated, and, when necessary, the plan of care must be adjusted during long-term treatment. Many patients will require additional treatment of comorbid psychiatric and substance use disorders and management of a variety of commonly co-occurring chronic general medical conditions.

Mice lacking circadian clock components display different mood-related behaviors and do not respond uniformly to chronic lithium treatment

Genomic studies suggest an association of circadian clock genes with bipolar disorder (BD) and lithium response in humans. Therefore, we tested mice mutant in various clock genes before and after lithium treatment in the forced swim test (FST), a rodent behavioral test used for evaluation of depressive-like states. We find that expression of circadian clock components, including Per2, Cry1 and Rev-erbα, is affected by lithium treatment, and thus, these clock components may contribute to the beneficial effects of lithium therapy. In particular, we observed that Cry1 is important at specific times of the day to transmit lithium-mediated effects. Interestingly, the pathways involving Per2 and Cry1, which regulate the behavior in the FST and the response to lithium, are distinct as evidenced by the phosphorylation of GSK3β after lithium treatment and the modulation of dopamine levels in the striatum. Furthermore, we observed the co-existence of depressive and mania-like symptoms in Cry1 knock-out mice, which resembles the so-called mixed state seen in BD patients. Taken together our results strengthen the concept that a defective circadian timing system may impact directly or indirectly on mood-related behaviors.

Group-based trajectory modeling: a novel approach to examining symptom trajectories in acute bipolar episodes

BACKGROUND

Pattern analysis can aid understanding of trajectories of symptom evolution. However, most studies focus on relatively homogeneous disorders with a restricted range of outcomes, prescribed a limited number of classes of medication. We explored the utility of pattern analysis in defining short-term outcomes in a heterogeneous clinical sample with acute bipolar disorders.

METHOD

In a naturalistic observational study, we used Group-based trajectory modeling (GBTM) to define trajectories of symptom change in 118 bipolar cases recruited during an acute DSM IV episode: major depression (56%), (hypo)mania (26%), and mixed states (18%). Symptoms were assessed weekly for a month using the MATHYS, which measures symptoms independent of episode polarity.

RESULTS

Four trajectories of symptom change were identified: Persistent Inhibition, Transient Inhibition, Transient Activation and Over-activation. However, counter to traditional predictions, we observed that bipolar depression shows a heterogeneous response pattern with cases being distributed approximately equally across trajectories that commenced with inhibition and activation.

LIMITATIONS

The observational period focuses on acute outcomes and so we cannot use the findings to predict whether the trajectories lead to stable improvement or whether the clinical course for some clusters is cyclical. As in all GBTM, the terms used for each trajectory are subjective, also the modeling programme we used assumes dropouts are random, which is clearly not always the case.

CONCLUSION

This paper highlights the potential importance of techniques such as GBTM in distinguishing the different response trajectories for acutely ill bipolar cases. The use of the MATHYS provides further critical insights, demonstrating that clustering of cases with similar response patterns may be independent of episodes defined by mood state.

Treatment of mixed bipolar states

Mixed bipolar states are associated with more severe symptoms and outcome. Our aim is to review the literature examining their treatment. We conducted a literature search of randomized clinical studies and post-hoc analyses on mixed bipolar states' treatment. Remarkably, there is only one double-blind, placebo-controlled trial, recruiting a mixed episode cohort, and one post-hoc analysis of this trial, while most data come from post-hoc analyses of trials including both manic and mixed patients. Improvement of manic symptoms in mixed episodes is similar to that seen in pure manic episodes and independent of baseline depressive features. The magnitude of response to manic symptoms' treatment probably exceeds that of depressive symptoms, which appear to resolve later. Valproate and carbamazepine are effective in acute mixed episodes, but the efficacy of lithium appears questionable. Atypical antipsychotic monotherapy improves both manic and depressive symptoms. Mood-stabilizer-atypical antipsychotic combination increases this effect. Atypical antipsychotic-antidepressant combination against acute mixed depression does not increase the risk for mania, although its superior efficacy vs. atypical antipsychotic monotherapy cannot be supported by current data. As regards prophylaxis, atypical antipsychotic monotherapy is associated with a lower incidence of and a longer time to relapse of any kind. The augmentation of lithium or divalproex with atypical antipsychotics increases prophylactic efficacy. Lithium or divalproex monotherapy have not been associated with significant prophylactic benefits following mixed mania. New, randomized prospective trials involving homogeneous cohorts of mixed bipolar patients are needed in order to delineate the appropriate pharmacological treatment of mixed states.

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 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.

A randomized open comparison of long-acting injectable risperidone and treatment as usual for prevention of relapse, rehospitalization, and urgent care referral in community-treated patients with rapid cycling bipolar disorder

OBJECTIVE

To compare adjunctive long-acting injectable risperidone plus treatment as usual (RLAI+TAU) versus TAU alone for relapse, rehospitalization, and urgent care events in patients with bipolar disorder in routine care settings.

METHODS

This was a 12-month randomized open comparison of RLAI+TAU (n = 20) and TAU alone (n = 25) in adults with rapid cycling, Mini International Neuropsychiatric Interview-confirmed bipolar I/II disorder and 4 or more illness relapses in the preceding 12 months. Clinical outcome was assessed every 2 weeks using the Longitudinal Interval Follow-up Evaluation instrument. Psychopathology and quality of life were assessed monthly using the Young Mania Rating Scale, Montgomery-Asberg Depression Rating Scale, Quick Inventory of Depressive Symptoms-Self Report 16 and Quality of Life, Enjoyment, and Satisfaction Questionnaire. Relapse was defined using symptom severity, necessary clinical adjustment of medications, and urgent care referrals. Relapse rates and duration were calculated per person per year of follow-up. All treatments were provided by community-based clinicians.

RESULTS

There were no significant between-groups differences in the total number or duration of relapse events (any cause) or in the number of manic or depressive relapses. Thirteen of 14 urgent care events (hospitalization, emergency department visit, intensive outpatient, or respite care referral) occurred with TAU alone (92.3%). Urgent care referral (P < 0.04) and necessary medication change rates (P = 0.01) were significantly lower in the RLAI+TAU group. There were no significant between-groups differences in the duration of follow-up, hospitalization rates, or psychopathology over time.

CONCLUSIONS

Rates of any-cause relapse may not differ significantly between RLAI+TAU and TAU alone; however, RLAI may reduce the need for urgent care referrals or the frequency of medication adjustments to prevent relapse in community-treated patients with rapid cycling bipolar disorder. Additional investigation is warranted.

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.

New ways to classify bipolar disorders: going from categorical groups to symptom clusters or dimensions

Current psychiatric disorder classifications are based exclusively on categorical models, which were designed to increase the reliability of diagnoses. However, this system has some limitations, and various psychiatric disorders may be classified using a dimensional approach, which is more appropriate when no clear boundaries exist between entities or when examining various features on a continuum. Thus, the forthcoming DSM-5 appears to be undertaking a hybrid approach by including categorical models associated with dimensions. We aim to review examples of dimensions or symptom clusters associated with a categorical approach that could be useful in refining bipolar disorder classification. We selected predominant polarity, psychotic symptoms, inhibition/activation behavioral level, and emotional reactivity to define mood episodes, impulsivity/suicidality/substance misuse, and cognitive impairment. The selection was based on the fact that these dimensions or symptom clusters are currently being discussed to be implemented in the DSM-5 and/or may orientate toward the choice of specific treatments and represent more homogeneous and thus more appropriate subgroups for research purposes. In the future, there will be a need to identify biomarkers that can definitively validate the use of these criteria.

Morbidity in 303 first-episode bipolar I disorder patients

OBJECTIVES

To test the hypotheses that: (i) depressive-dysthymic-dysphoric (D-type) morbidity is more prevalent than manic-hypomanic-psychotic (M-type) morbidity even from first episodes of bipolar I disorder (BPD-I) and despite treatment; (ii) initial presentations predict later morbidity; (iii) morbidity varies internationally; and (iv) early and later morbidity are similar.

METHODS

We followed SCID-based, DSM-IV BPD-I patients (n = 303) systematically and prospectively for two years to estimate the percent of weeks in specific morbid states from first lifetime major episodes.

RESULTS

Total morbidity accounted for 44% of the first two years, and D-type exceeded M-type illnesses by 2.1-fold (30%/14%) among morbidities ranking: mixed states (major + minor) >or= dysthymia >or= mania >or= major depression > hypomania > psychosis. In 164 cases, morbidities at 0.5-2.5 and 2.5-4.5 years were very similar. Depressive or mixed initial episodes predicted a 3.6-fold excess of D-type morbidity, and initial M-type episodes predicted a 7.1-fold excess of M-type morbidity over two years. Morbidity in European (EU) sites was nearly half that in the U.S., and 22% greater overall among men than women. In five comparable studies, illness accounted for 54% of follow-up time, and the ratio of D/M morbidity averaged 3.0.

CONCLUSIONS

In accord with four midcourse studies, morbidity from BPD-I onset, despite treatment by community standards, averaged 44%, was 68% D-type morbidity, and was strongly predicted by first-episode polarity. Lower morbidity in EU than U.S. sites may reflect differences in healthcare or social systems.

Is lithium in a class of its own? A brief profile of its clinical use

Lithium is a unique and effective psychotropic agent with a long-standing history of clinical use yet it is increasingly overlooked in lieu of newer agents. The purpose of the present paper was to succinctly review the therapeutic profile of lithium particularly with respect to the treatment of mood disorders and consider its unique properties and clinical utility. A comprehensive literature review pertaining to lithium was undertaken using electronic database search engines to identify relevant clinical trials, meta-analyses and Cochrane reviews. In addition articles and book chapters known to the authors were carefully reviewed, and the authors appraised published guidelines. The evidence from these sources was rated using National Health and Medical Research Council evidence levels and synthesized according to phenotype and mood states. In addition, the authors have drawn upon published guidelines and their own clinical experience. Lithium has specificity for mood disorders with proven efficacy in the treatment of both unipolar depression and bipolar disorder. The recommendations are based predominantly on Level I evidence, but its clinical use has to be tempered against potential side-effects and the need for ongoing monitoring. In practice, lithium should be considered a first-line option in bipolar disorder, especially in prophylaxis and when onset of action is not an imperative. Lithium has been in use in modern medicine for 60 years and as such has been tried and tested across the full range of mood disorders. Arguably, lithium is the only true mood stabilizer and because of its unique properties is in a class of its own.