Treatment of Bipolar Depression: Evolving Recommendations

Prevention of suicidal behavior with lithium treatment in patients with recurrent mood disorders

Suicidal behavior is more prevalent in bipolar disorders than in other psychiatric illnesses. In the last thirty years evidence has emerged to indicate that long-term treatment of bipolar disorder patients with lithium may reduce risk of suicide and attempts, with possibly similar benefits in recurrent major depressive disorder. We review and update selected research literature on effects of lithium treatment in reducing suicidal behavior and consider proposals that higher levels of lithium in drinking water may be associated with lower suicide rates. We summarize results of a growing number of randomized, controlled studies of lithium treatment for suicide prevention including comparisons with placebos or alternative treatments, and comment on the severe challenges of such trials. The basis of a proposed protective effect of lithium against suicidal behaviors remains uncertain but may include protective effects against recurrences of depressive phases of mood disorders, especially with mixed features or agitation, and possibly through beneficial effects on impulsivity, agitation and dysphoric mood.

Ketogenic-Mimicking Diet as a Therapeutic Modality for Bipolar Disorder: Biomechanistic Rationale and Protocol for a Pilot Clinical Trial

There is growing interest in the investigation of ketogenic diets as a potential therapy for bipolar disorder. The overlapping pharmacotherapies utilized for both bipolar disorder and seizures suggest that a mechanistic overlap may exist between these conditions, with fasting and the ketogenic diet representing the most time-proven therapies for seizure control. Recently, preliminary evidence has begun to emerge supporting a potential role for ketogenic diets in treating bipolar disorder. Notably, some patients may struggle to initiate a strict diet in the midst of a mood episode or significant life stressors. The key question addressed by this pilot clinical trial protocol is if benefits can be achieved with a less restrictive diet, as this would allow such an intervention to be accessible for more patients. Recent development of so-called ketone esters, that once ingested is converted to natural ketone bodies, combined with low glycemic index dietary changes has the potential to mimic two foundational components of therapeutic ketosis: high levels of ketones and minimal spiking of glucose/insulin. This pilot clinical trial protocol thus aims to investigate the effect of a 'ketogenic-mimicking diet' (combining supplementation of ketone esters with a low glycemic index dietary intervention) on neural network stability, mood, and biomarker outcomes in the setting of bipolar disorder. Positive findings obtained via this pilot clinical trial protocol may support future target engagement studies of ketogenic-mimicking diets or related ketogenic interventions. A lack of positive findings, in contrast, may justify a focus on more strict dietary interventions for future research.

Possible Antidepressant Effects of Memantine-Systematic Review with a Case Study

The treatment of bipolar depression is hampered by the inadequate efficacy of antidepressants, moderate effect of mood stabilizers, and the side effects of some second-generation antipsychotics. There is limited evidence to date regarding the antidepressant effects of memantine in bipolar depression. The aim of the article was to provide a short review of preclinical and clinical studies on the antidepressant effect of memantine, and to present the case of a bipolar depression patient successfully treated with memantine. The described patient with bipolar disorder was unsuccessfully treated with two mood stabilizers. The addition of memantine at a dose of 20 mg/d to the treatment with lamotrigine and valproic acid resulted in a reduction in the severity of depression measured on the HDRS-17 scale by 35%, and by 47.1% after 7 weeks. The discussion presents experimental evidence for the antidepressant effect of memantine, as well as data from clinical trials in recurrent and bipolar depression. The presented case is the second report in the medical literature showing the antidepressant effect of memantine as an add-on treatment for bipolar depression. The described case and literature analysis indicate that memantine may be an effective and safe method of augmentation of mood stabilizing therapy in bipolar depression.

The Kindling/Sensitization Model and Early Life Stress

INTRODUCTION

Few animal models address the characteristics of the longitudinal course of bipolar disorder. However, behavioral sensitization (to recurrent stressors and psychomotor stimulants) and kindling of seizures both provide clues to mechanisms in the progressive course of bipolar disorder.

METHODS

We describe aspects of bipolar illness that show sensitization and kindling-like increases reactivity to the recurrence of stressors, mood episodes, and bouts of substance abuse. Mechanisms of these events and clinical implications for treatment are discussed.

RESULTS

Early life stress is a risk factor for the development of episodes of unipolar depression and bipolar disorder and the acquisition of substance abuse. Initial affective episodes are often triggered by the recurrence of psychosocial stressors in adulthood, but after many episodes have occurred, episodes may also begin to emerge spontaneously in a kindling-like progression. More prior episodes are associated with faster recurrences, dysfunction, disability, frontal cortical abnormalities, cognitive impairment, shorter telomeres, treatment refractoriness, and an increased risk of a diagnosis of dementia in old age. Sensitization to stressors, episodes, and substances of abuse each appear driven by epigenetic mechanisms and their accumulation on DNA, histones, and microRNA. Patients with bipolar illness in the USA are more ill than those from Europe and experience more sensitization to stressors, episodes, substance abuse, as well as more genetic vulnerability across four generations.

DISCUSSION

The sensitization and kindling models highlight the importance of early intervention and prevention in order to limit or halt the downhill progression of bipolar disorder and its multiple comorbidities toward treatment refractoriness. Clinical data support this conclusion as well but have not been sufficient to change practice in the direction of early intervention. It is hoped that a better understanding of sensitization and kindling-like mechanisms will add neurobiological rationales for the importance of prevention and sustained prophylactic intervention in rendering bipolar disorder a more benign illness.

Emotional regulation neural circuitry abnormalities in adult bipolar disorder: dissociating effects of long-term depression history from relationships with present symptoms

Bipolar disorder (BD) is common and debilitating and confounding effects of depression history on neural activity in BD are unknown. We aimed to dissociate neural activity reflecting past depression-load vs. present symptom severity using the Course and Outcome of Bipolar Youth (COBY), a prospective longitudinal cohort study of pediatric-onset BD. In n = 54 COBY (18-32 years), we modeled depression scores over time (up to 17.5 years) using a standardized autoregressive moving average (ARMA) model, followed by k-means cluster analysis. N = 36 healthy participants (HC, 20-36 years) were included. Using two factorial analyses, we parsed the impact of ARMA-defined past depression-load on neural activity from the impact of current symptoms on neural activity (p < 0.001, k > 30) and examined relationships with past and present symptoms (ps FDR-corrected). ARMA identified three COBY groups based on past depression-load. ARMA-defined COBY participants with the greatest past depression-load vs. other groups showed greater activity in right temporoparietal junction, thalamus, insula, premotor cortex, left fusiform gyrus, bilateral precuneus and cerebellum. In contrast, BD-COBY participants vs. HC showed greater activity in left hippocampus, dorsolateral prefrontal cortex, and right somatosensory cortex, plus the above thalamus, premotor cortex and cerebellum; activity positively correlated with present symptom severity in most regions. Past depression-load was related to social cognition and salience perception network activity, potentially reflecting heightened attention to socially relevant distracters, while present symptoms were associated with emotion processing and reappraisal network activity, potentially reflecting abnormal emotional experience and regulation. Differentiating aberrant neural activity related to long-term depression vs. present affective symptoms can help target interventions to networks associated with pathophysiological processes, rather than long-term illness effects.

Possibility of a New Indication for Amantadine in the Treatment of Bipolar Depression-Case Series Study

Bipolar disorder is a chronic and remitting mental illness. Antidepressants are not effective in treating acute bipolar depression, and antipsychotic drugs used in the treatment of bipolar depression cause frequent side effects. This situation justifies the search for new drugs as well as the repurposing of drugs used in other indications. In an open and naturalistic serious case study, 4 patients diagnosed with bipolar I disorder, chronically treated with a mood stabilizer, in whom at least two antidepressants were ineffective in the depressive phase, were treated with amantadine. The woman received 100 mg/day and 3 men received the target dose of 200 mg/day. All patients treated with amantadine improved their depressive symptoms after 1 week of treatment. None of them experienced side effects or manic switch. To reduce the risk of a manic switch, the treatment with amantadine was discontinued 2 weeks after the improvement of depressive symptoms, and no recurrence of depressive symptoms was observed. Amantadine may be a further therapeutic option for the treatment of acute bipolar depression. The drug in this indication may act quickly and be well tolerated. Confirmation of the antidepressant efficacy of amantadine in this indication requires replication of the results and conducting clinical trials.

Hospitalization trends and chronobiology for mental disorders in Spain from 2005 to 2015

Rhythm research has had a long tradition in psychiatry, especially in affective disorders. The study of trends in incidence plays a central role in epidemiology and public health. The aims of this research were to describe the socio-demographic and clinical characteristics of persons admitted for psychiatric hospitalization and their trends and periodicity in cases (global and by groups) in Spain over the 11 year study span. We conducted a cross-sectional study of the hospital discharge database of Castilla y León from 2005 to 2015, selecting hospitalizations for psychiatric reasons. Trends in the rates of hospitalization were studied by joinpoint regression analysis. Time series analysis for periodicities was done by spectral analysis, fast Fourier transform, and cosinor analysis. Some 49501 hospitalizations due to psychiatric disorders, out of 2717192 hospital admissions, took place during the study span. Hospitalizations for psychosis were frequent (15949, 32.2%), while such for eating disorders were infrequent, but showed the highest average stay (28 days) and DRG relative weight (2.41). The general trend was a statistically significant 2% annual increase in psychiatric hospitalizations over the 11 year span; substance abuse was the only exception to this trend. The whole population and the subgroups of psychosis and bipolar disorders showed significant circannual (one-year) variation in admissions. The rhythm percentage of the global group was 11.4%, while the rhythm percentages of the psychosis, bipolar, and eating disorders were 17.1%, 17.5%, and 9.6%, respectively (p < .05).

Toward prevention of bipolar disorder in at-risk children: Potential strategies ahead of the data

BACKGROUND

Despite the well-documented negative impact of untreated bipolar illness, approaches to early intervention in childhood-onset bipolar and related disorders are not well delineated.

METHODS

We reviewed the extant treatment literature on children at high risk for bipolar disorder, with definitions based on family history, childhood adversity, and prodromal symptoms.

RESULTS

A panoply of approaches have been described, but most interventions are based on an inadequate database to support their routine implementation. We classify early stage interventions as a function of their safety and tolerability with the hope that these might generate more rigorous study and a stronger database.

LIMITATIONS

Critics may rightly argue that identifying viable treatment methods is premature given our lack of ability to reliably predict illness trajectory in very young children. However, many of the psychosocial and pharmacological interventions we present could have nonspecific positive effects across a variety of symptoms, syndromes, and diagnoses, further enhancing the rationale for more rigorous study.

CONCLUSIONS

Early stage interventions have the potential to improve functioning in prodromal illness and exert long-term positive effects on the course of illness. Many of the safest interventions deserve consideration for implementation and dissemination studies.

Evaluation of cariprazine in the treatment of bipolar I and II depression: a randomized, double-blind, placebo-controlled, phase 2 trial

This double-blind placebo-controlled, fixed/flexible-dose phase 2 trial assessed the efficacy, safety, and tolerability of cariprazine vs. placebo for depressive episodes associated with bipolar I or II disorder. Primary endpoint was change in Montgomery-Åsberg Depression Rating Scale (MADRS) total scores (baseline to week 8), and secondary endpoint was mean Clinical Global Impressions-Improvement score (week 8). Patients were randomized (N = 233) 1:1:1 to placebo, 'low-dose' 0.25-0.5 mg/day or 'high-dose' 1.5-3.0 mg/day cariprazine. Adverse events, laboratory results, vital signs, extrapyramidal symptoms, and suicide risk were monitored. Neither cariprazine group significantly separated from placebo in primary (mixed-effect model repeated measures MADRS least-squares mean differences: low-dose = -0.7, P = 0.7408; high-dose = 0.0, P = 0.9961) or secondary efficacy measures. No new safety signals with cariprazine were observed and common treatment-emergent adverse events (≥5% of cariprazine patients and twice the rate of placebo) included insomnia, akathisia, dry mouth, nausea, weight increased, diarrhea, restlessness, vomiting, musculoskeletal stiffness, migraine, and cough. Metabolic and weight changes were generally similar for cariprazine and placebo. Factors that may have affected the outcome of the trial were identified, which helped to inform the design and conduct of subsequent phase 2b/3 clinical trials of cariprazine in bipolar depression.

Beyond evidence-based treatment of bipolar disorder: Rational pragmatic approaches to management

The evidence for efficacy of many currently available treatments for bipolar disorder is based on studies of nonrefractory patients with bipolar disorder. Therefore, not surprisingly, most treatment recommendations and guidelines for the treatment of bipolar disorder and its many comorbidities depend heavily on data from placebo controlled randomized clinical trials (RCTs), but these RCTs provide little direction for the clinician as to what next steps might be optimal in non- or partial-responders and in those with ongoing medical and psychiatric comorbidities. Given this and the paucity of RCTs at later treatment junctures, we thought it appropriate to begin a discussion of the quality of the data that some experts in the field might consider using in choosing and sequencing drugs and their combination. We acknowledge that many other clinical investigators may prefer very different sequences, but thought the suggestions offered here might be useful to some clinicians in the field, might start discussions of other options in the literature, and, at the same time, provide a preliminary outline for a new round of much-needed clinical trials to better inform clinical practice. Given the very wide range of the quality of the data and clinical principles on which the current suggestions are based, only minimal references are included and a comprehensive review of the literature supporting each option would be outside the scope of this manuscript.

Systems Biology Understanding of the Effects of Lithium on Cancer

Lithium has many widely varying biochemical and phenomenological effects, suggesting that a systems biology approach is required to understand its action. Multiple lines of evidence point to lithium as a significant factor in development of cancer, showing that understanding lithium action is of high importance. In this paper we undertake first steps toward a systems approach by analyzing mutual enrichment between the interactomes of lithium-sensitive enzymes and the pathways associated with cancer. This work integrates information from two important databases, STRING, and KEGG pathways. We find that for the majority of cancer pathways the mutual enrichment is statistically highly significant, reinforcing previous lines of evidence that lithium is an important influence on cancer.

Systems Biology Understanding of the Effects of Lithium on Affective and Neurodegenerative Disorders

Lithium has many widely varying biochemical and phenomenological effects, suggesting that a systems biology approach is required to understand its action. Multiple lines of evidence point to lithium intake and consequent blood levels as important determinants of incidence of neurodegenerative disease, showing that understanding lithium action is of high importance. In this paper we undertake first steps toward a systems approach by analyzing mutual enrichment between the interactomes of lithium-sensitive enzymes and the pathways associated with affective and neurodegenerative disorders. This work integrates information from two important databases, STRING and KEGG pathways. We find that for the majority of neurodegenerative disorders the mutual enrichment is many times greater than chance, reinforcing previous lines of evidence that lithium is an important influence on incidence of neurodegeneration. Our work suggests rational prioritization for which disorders are likely to be most sensitive to lithium and identifies genes that are likely to be useful targets for therapy adjunct to lithium.

Genetic polymorphisms associated with circadian rhythm dysregulation provide new perspectives on bipolar disorder

OBJECTIVES

The objective of this study was to present a broad view of how genetic polymorphisms in genes that control the rhythmicity and function of circadian rhythm may influence the etiology, pathophysiology and treatment of bipolar disorder (BD).

METHODS

A bibliographic search was performed to identify and select papers reporting studies on variations in circadian genes and BD. A search of Medline, Google Scholar, Scopus, and Web of Science was carried out to review the literature.

RESULTS

Several studies provide evidence of contributions of variations in circadian genes to disease etiology, pathophysiological variations and lithium drug response. Dysfunction of the sleep-wake cycle, an important brain function regulator, is indicated as the primary means by which circadian gene variations act in mood disorders.

CONCLUSIONS

Investigations of the effects of circadian genes have suggested that the chronotype offers hope for guiding and improving management of patients with BD. However, BD is a disease of a complex nature and presents multiple endophenotypes determined by different associations between genetics and the environment. Thus, new genomic studies to delimit variations that may help improve the clinical condition of these patients are extremely important.

The New News about Lithium: An Underutilized Treatment in the United States

Lithium use for the treatment of mood disorders remains quite low, particularly in the United States compared with some European countries. Mogens Schou pioneered the study of lithium for prophylaxis of the recurrent mood disorder and encouraged its greater use. In an effort to further address the appropriate role of this drug, the multiple assets of lithium beyond its well-known antimanic effect are reviewed, and a brief summary of its side effects is outlined. It appears that lithium has positive effects in depression and suicide prevention, cognition, and reducing the incidence of dementia. It increases the length of telomeres and has positive effects in prevention of some medical illnesses. Lithium side-effect burden, especially its association with end-stage renal disease, may be less than many have surmised. New data indicate the importance of long-term prophylaxis after a first manic episode to lessen episode recurrence, allow cognition to recover to normal, and prevent various aspects of illness progression. After a first manic episode, 1 year of randomized treatment with lithium was superior to that of quetiapine, suggesting the importance of having lithium in the treatment regimen. Given the highly recurrent and progressive course of bipolar disorder sometimes even in the face of conventional treatment, the role and enhanced use of lithium deserves reconsideration.

The Use of Antidepressants in Bipolar Depression

Depression remains a significant debilitating and frequent phase of illness for patients with bipolar disorder. There are few FDA-approved medications for its treatment, only one of which includes a traditional antidepressant (olanzapine-fluoxetine combination), despite studies that demonstrate traditional antidepressants are one of the most commonly prescribed class of medications for bipolar patients in a depressive episode. While traditional antidepressants remain the primary option for treatment of unipolar depression, their use in bipolar depression has been controversial due to a limited efficacy evidence and the concern for potential harm. This chapter reviews the current data concerning the use of traditional antidepressants in bipolar disorder, and the current expert treatment guideline recommendations for their use.

Lurasidone in the Treatment of Bipolar Depression: Systematic Review of Systematic Reviews

INTRODUCTION

A burgeoning number of systematic reviews considering lurasidone in the treatment of bipolar depression have occurred since its Food and Drug Administration extended approval in 2013. While a paucity of available quantitative evidence still precludes preliminary meta-analysis on the matter, the present quality assessment of systematic review of systematic reviews, nonetheless, aims at highlighting current essential information on the topic.

METHODS

Both published and unpublished systematic reviews about lurasidone mono- or adjunctive therapy in the treatment of bipolar depression were searched by two independent authors inquiring PubMed/Cochrane/Embase/Scopus from inception until October 2016.

RESULTS

Twelve included systematic reviews were of moderate-to-high quality and consistent in covering the handful of RCTs available to date, suggesting the promising efficacy, safety, and tolerability profile of lurasidone. Concordance on the drug profile seems to be corroborated by a steadily increasing number of convergent qualitative reports on the matter.

LIMITATIONS

Publication, sponsorship, language, citation, and measurement biases.

CONCLUSIONS

Despite being preliminary in nature, this overview stipulates the effectiveness of lurasidone in the acute treatment of Type I bipolar depression overall. As outlined by most of the reviewed evidence, recommendations for future research should include further controlled trials of extended duration.

Which component of treatment is important for changes of cortical epileptic afterdischarges after status epilepticus in immature rats?

Role of lithium chloride and paraldehyde in acute changes after lithium-pilocarpine status epilepticus (SE) induced at postnatal day 12 was studied in 15-day-old rats. In addition to SE group four other groups were formed: naïve animals without any injection, lithium chloride group, paraldehyde group and lithium-paraldehyde group. Cortical epileptic afterdischarges (CxADs) induced by increasing intensities of stimulation current were used as a measure of excitability. SE animals did not exhibit any change in duration of CxADs with increasing stimulation intensity in contrast to naïve control with a progressive prolongation of CxAD. LiCl group was similar to SE rats whereas paraldehyde and lithium-paraldehyde groups exhibited some progress in duration of ADs. Lithium chloride participates in short-term changes of CxADs after SE. Paraldehyde and combination of lithium and paraldehyde are similar to naïve controls.

Suicidal Behavior in Mood Disorders: Response to Pharmacological Treatment

Suicidal behavior is strongly associated with depression, especially if accompanied by behavioral activation, dysphoria, or agitation. It may respond to some treatments, but the design of scientifically sound, ethical trials to test for therapeutic effects on suicidal behavior is highly challenging. In bipolar disorder, and possibly also unipolar major depression, an underprescribed medical intervention with substantial evidence of preventive effects on suicidal behavior is long-term treatment with lithium. It is unclear whether this effect is specifically antisuicidal or reflects beneficial effects of lithium on depression, mood instability, and perhaps aggression and impulsivity. Antisuicidal effects of anticonvulsant mood stabilizers (carbamazepine, lamotrigine, valproate) appear to be less than with lithium. Further evaluation is needed for potential antisuicidal effects of atypical antipsychotics with growing evidence of efficacy in depression, particularly acute bipolar depression, while generally lacking risk of inducing agitation, mania, or mood instability. Short-term and long-term value and safety of antidepressants are relatively secure for unipolar depression but uncertain and poorly tested for bipolar depression; their effects on suicidal risk in unipolar depression may be age-dependent. Sedative anxiolytics are virtually unstudied as regards suicidal risks. Adequate management of suicidal risks in mood disorder patients requires comprehensive, clinically skillful monitoring and timely interventions.

Functional Implications of the CLOCK 3111T/C Single-Nucleotide Polymorphism

Circadian rhythm disruptions are prominently associated with bipolar disorder (BD). Circadian rhythms are regulated by the molecular clock, a family of proteins that function together in a transcriptional-translational feedback loop. The CLOCK protein is a key transcription factor of this feedback loop, and previous studies have found that manipulations of the Clock gene are sufficient to produce manic-like behavior in mice (1). The CLOCK 3111T/C single-nucleotide polymorphism (SNP; rs1801260) is a genetic variation of the human CLOCK gene that is significantly associated with increased frequency of manic episodes in BD patients (2). The 3111T/C SNP is located in the 3'-untranslated region of the CLOCK gene. In this study, we sought to examine the functional implications of the human CLOCK 3111T/C SNP by transfecting a mammalian cell line (mouse embryonic fibroblasts isolated from Clock(-/-) knockout mice) with pcDNA plasmids containing the human CLOCK gene with either the T or C SNP at position 3111. We then measured circadian gene expression over a 24-h time period. We found that the CLOCK3111C SNP resulted in higher mRNA levels than the CLOCK 3111T SNP. Furthermore, we found that Per2, a transcriptional target of CLOCK, was also more highly expressed with CLOCK 3111C expression, indicating that the 3'-UTR SNP affects the expression, function, and stability of CLOCK mRNA.