Treatment-resistant bipolar depression: towards a new definition

Role of Electroconvulsive Therapy, Ketamine Infusion, and Deep Repetitive Transcranial Magnetic Stimulation in Treatment-Resistant Bipolar Depression: A Case Report

Background and Objectives: Options for treatment-resistant bipolar depression (TRBPD) are limited. Electroconvulsive therapy (ECT) has shown efficacy in TRBPD. However, the cognitive deficits and memory concerns associated with ECT are problematic for a significant number of patients. It remains unclear what the next step is for patients with TRBPD who fail ECT. Materials and Methods: In this case report, we present a patient with TRBPD who sequentially received 12 sessions of brief-pulse right unilateral ECT, 22 sessions of ketamine infusion at 0.5-0.75 mg/kg for 40 min, and 39 sessions of deep repetitive transcranial magnetic stimulation (dTMS). Results: The patient had some benefit from ECT, but declined continuation of ECT due to memory concerns. The patient tolerated ketamine infusion well but had limited benefit. However, the patient responded well to acute treatment with dTMS and maintained relative stability for more than 2 years. Conclusions: This case suggests that patients with TRBPD who fail ECT and/or ketamine infusion might benefit from dTMS.

Esketamine-induced post-traumatic stress disorder flashbacks during treatment-resistant depression indication: is it just a side effect?

Background

Posttraumatic stress disorder (PTSD) is a severe and frequent affection that is highly comorbid to major depressive disorder. Comorbid PTSD and depression are usually treatment-resistant, with a high risk of functional impairment and suicide. Esketamine nasal spray is a recent validated treatment for treatment-resistant depression (TRD), but its efficacy on comorbid TRD-PTSD remains insufficiently documented. In particular, flashbacks can occur during esketamine administration and their influence on clinical outcomes is unknown.

Objectives

Our main objective was to describe esketamine-induced traumatic flashbacks and their impact on clinical trajectories within a sample of patients with comorbid TRD-PTSD.

Methods

We retrospectively collected clinical data of patients receiving esketamine nasal spray for TRD with comorbid PTSD who experienced at least one flashback of their trauma during esketamine sessions across 11 psychiatric departments.

Results

Between February 2020 and March 2023, 22 adult patients with TRD met inclusion criteria. In sixteen patients (72.7%) flashbacks disappeared as the sessions progressed. In six patients (27.3%), esketamine treatment was stopped because of persistent flashbacks. When esketamine was continued, clinical response was observed both for depression and PTSD (depression response rate: 45.5% and remission rate: 22.7%; PTSD response rate: 45.5% and remission: 18.2%).

Limitations

The retrospective design of the study and the absence of a comparator group are the main limitations of our study.

Conclusions

Our results suggest that the occurrence of esketamine-induced traumatic flashbacks does not hinder clinical response. On the contrary, when managed appropriately and combined with targeted psychotherapy, it could even contribute to positive outcomes.

A 6-month follow-up study on response and relapse rates following an acute trial of repetitive transcranial magnetic stimulation in patients with major depression

BACKGROUND

Little is known about the post-acute effects of repetitive transcranial magnetic stimulation (rTMS) in patients with major depression. The present study focused on the 6-month follow-up of a sample of patients with major depression, after the completion of an acute 4 weeks rTMS trial, with the aim of evaluating response (in terms of sustained and late response) and relapse rates.

METHODS

Following the completion of an acute trial of rTMS (T0-T4), 31 drug-resistant depressed patients (bipolar or unipolar) entered a naturalistic follow-up period of 6 months, with three timepoints (T5, T6, and T7) during which they were assessed with the Hamilton Depression Rating Scale and the Young Mania Rating Scale.

RESULTS

Results showed that in the 6 months following an acute transcranial magnetic stimulation (TMS) trial, a higher rate of late responders was observed among previously acute TMS nonresponders (63.64%, 7 out of 11) compared to the rate of relapse among those who had acutely responded to TMS (10%, 2 out of 20). In addition, an overall high rate of maintained response (90%) was observed.

CONCLUSION

Present findings seem to support the possibility of obtaining a clinical response also after the end of an acute TMS trial in patients with major depression. The concomitant low rate of relapse observed at the end of follow-up along with a high rate of maintained response provides further support to the post-acute efficacy of TMS. Nonetheless, further controlled studies, with larger samples and longer follow-up observation, are needed to confirm the reported results.

Treatment-Resistant Bipolar Depression: Therapeutic Trends, Challenges and Future Directions

INTRODUCTION

Bipolar disorder (BD) is a chronic mental illness impacting 1-2% of the population worldwide and causing high rates of functional impairment. Patients with BD spend most of their time in depressive episodes and up to one-third of patients do not respond to adequate doses of medications. Although no consensus exists for definition of treatment-resistant bipolar depression (TRBD), failure of symptoms improvement despite an adequate trial of two therapeutic agents is a common theme of TRBD. In this paper, we review the evidence base of therapeutic interventions, challenges, and potential future directions for TRBD.

METHODS

We conducted a literature search for randomized controlled trials on PubMed for the treatment of TRBD and ongoing trials for the treatment of TRBD/bipolar depression on clinicaltrials.gov.

RESULTS

Several therapeutic agents have been investigated for TRBD. Adjunctive pramipexole and modafinil have data supporting short-term efficacy in TRBD, along with limited data for racemic intravenous ketamine. Celecoxib augmentation of escitalopram and treatment with metformin in patients with insulin resistance showed promising results. Right unilateral electroconvulsive therapy displayed statistically significant response rate and improvement, but not remission compared to pharmacotherapy. Trials for transcranial magnetic stimulation (TMS) have failed to show a significant difference from sham treatment in TRBD.

FUTURE TRENDS

Pharmacological treatments with novel mechanisms of actions like brexpiprazole and vortioxetine are being investigated following successes in unipolar depression. Modified TMS protocols such as accelerated TMS are under investigation. Innovative approaches like psychedelic-assisted psychotherapy, interleukin-2, fecal microbiota transplantation and multipotent stromal cells are being studied.

CONCLUSION

Evidence on current treatment modalities for TRBD is limited with low efficacy. More research is needed for successful treatment of TRBD. Effective therapies and innovative approaches to treatment are being investigated and could show promise.

Treatment-resistant bipolar depression: concepts and challenges for novel interventions

Treatment-resistant bipolar depression (TRBD) has been reported in about one-quarter of patients with bipolar disorders, and few interventions have shown clear and established effectiveness. We conducted a narrative review of the published medical literature to identify papers discussing treatment-resistant depression concepts and novel interventions for bipolar depression that focus on TRBD. We searched for potentially relevant English-language articles published in the last decade. Selected articles (based on the title and abstract) were retrieved for a more detailed evaluation. A number of promising new interventions, both pharmacological and non-pharmacological, are being investigated for TRBD treatment, including ketamine, lurasidone, D-cycloserine, pioglitazone, N-acetylcysteine, angiotensin-converting enzyme inhibitors, angiotensin II type 1 receptor blockers, cyclooxygenase 2 inhibitors, magnetic seizure therapy, intermittent theta-burst stimulation, deep transcranial magnetic stimulation, vagus nerve stimulation therapy, and deep brain stimulation. Although there is no consensus about the concept of TRBD, better clarification of the neurobiology associated with treatment non-response could help identify novel strategies. More research is warranted, mainly focusing on personalizing current treatments to optimize response and remission rates.

A case of treatment-resistant bipolar depression and comorbid OCD treated with deep brain stimulation of the medial forebrain bundle: 5 years follow-up results

Limited though promising evidence exists on the efficacy of Deep Brain Stimulation (DBS) of the Medial Forebrain Bundle (MFB) in otherwise intractable patients with Major Depression and Obsessive-Compulsive Disorder (OCD). Herein, we present acute and follow-up results (up to 5 years) of a 42 year old man with a diagnosis of treatment-resistant Bipolar Depression (BD) and comorbid OCD, successfully treated with DBS of the MFB. Regular follow-up visits with psychometric evaluations highlighted a considerable improvement of patient's depressive and OC symptoms at 5 years from implant. According to the limited, reported experience, we support the efficacy and tolerability of DBS of the MFB as a promising intervention in patients with treatment-resistant BD and comorbid OCD, with specific emphasis on the long-term outcome.

Clinical features associated with early drop-out among outpatients with unipolar and bipolar depression

Drop-out from follow-up visits carries significant burden for people diagnosed with depression. The present study assesses multiple clinical moderators of drop-out among depressed outpatients. We retrospectively followed-up 131 outpatients over 6 months: 78 major depressive disorder (MDD), and 53 bipolar disorder (BD-I = 24; BD-II = 29) patients diagnosed according to the Diagnostic and Statistical Manual for Mental Disorders, Fifth Edition. Participants were assessed with standard rating scales administered by experienced psychiatrists. Upon descriptive and Cox regression analyses, 17/53 BDs (32%) dropped-out; the overall survival time until drop-out was 57.94 ± 17.79 days. BD drop-outs were younger, had an earlier age at onset, shorter illness duration, lower rates of lifetime obsessive-compulsive disorder/suicidal behavior, higher rates of substance use disorder (SUD), anxious and mixed features of depression compared to BDs attending up to six months. Among MDD patients, 10/78 cases (13%) dropped-out by month-6 with an average survival of 42.40 ± 16.45 days. Earlier age of onset, younger age, positive family history for mood disorders, lower rates of lifetime generalized anxiety disorder were significantly more frequent among drop-outs than completers, as opposite to SUD, and lifetime recurrent depression. Older age predicted lower drop-out among BDs and MDDs, although with almost null hazard ratio (HR) = 0.928, p < 0.01 vs. HR = 0.941, p < 0.01, respectively. Higher rates of lifetime SUD predicted higher drop-out rates by month-6 among MDDs (HR = 5.477, p = 0.02). Limitations of the study: retrospective design, small sample size, lack of objective measures of treatment-adherence/mood rating during follow-up. Drop-out is common in the real-world setting, warranting specific interventions since the beginning of the treatment.

Using classification and regression tree modelling to investigate treatment response to a single low-dose ketamine infusion: Post hoc pooled analyses of randomized placebo-controlled and open-label trials

BACKGROUND

Evidence suggests that clinical markers, such as comorbid anxiety, body weight, and others can assist in predicting response to low-dose ketamine infusion in treatment resistant depression patients. However, whether a composite of clinical markers may improve the predicted probability of response is uncertain.

METHODS

The current study investigated the results of our previous randomized placebo-controlled and open-label trials in which 73 patients with treatment-resistant depression (TRD) received a single ketamine infusion of 0.5 mg/kg. Clinical characteristics at baseline, including depression severity, duration of the current episode, obesity, comorbidity of anxiety disorder, and current suicide risk, were assessed as potential predictors in a classification and regression tree model for treatment response to ketamine infusion.

RESULTS

The predicted probability of a composite of age at disease onset, depression severity, duration of current episode, and obesity/overweight was significantly greater (area under curve = .736, p = .001) than that of any one marker (all p > .05). The most powerful predictors of treatment response to ketamine infusion were younger age at disease onset and obesity/overweight. The strongest predictors of treatment nonresponse were longer duration of the current episode and greater depression severity at baseline.

DISCUSSION

Depression severity, duration of the current episode, obesity, and age at disease onset may predict treatment response versus nonresponse to low-dose ketamine infusion. However, whether our predicted probability for a single infusion may be applied to repeated infusions would require further investigation.

CLINICAL TRIAL REGISTRATION

UMIN Clinical Trials Registry (UMIN000023581 and UMIN000016985).

The concept and management of acute episodes of treatment-resistant bipolar disorder: a systematic review and exploratory meta-analysis of randomized controlled trials

BACKGROUND

The definitions of treatment-resistant bipolar disorder (TRBD) have varied across studies. Additionally, its management is clinically challenging. An updated synthesis and appraisal of the available evidence is needed.

METHODS

A systematic search of major electronic databases from inception up to May 25th, 2020, was conducted to identify randomized controlled trials (RCTs) of pharmacological and non-pharmacological interventions for the management of TRBD. When sufficient evidence was available, a meta-analysis was conducted.

RESULTS

Seventeen studies (n = 928 patients) were included in the qualitative synthesis. Fourteen studies (n = 803) assessed treatment-resistant acute bipolar depression (TRBD-De), including five neuromodulatory and nine pharmacological trials. Rapid- vs. standard up-titration of clozapine showed promising efficacy for TRBD mania, without significant adverse events. Electroconvulsive therapy (ECT) was confirmed to be similarly effective for TRBD-De as for treatment-resistant unipolar depression: odd ratio, OR = 0.919 (95%C.I. = 0.44-1.917), I² = 13.98, p = .822. TRBD-De patients exposed to ketamine at day one post-infusion had high odds of response: OR = 10.682 (95%C.I. = 2.142-53.272), I² = 0, p = <.005. The pooled drop-out rate in the ketamine trials was 21.2%. Additional evidence is warranted to confirm the potential efficacy of pramipexole or stimulants for TRBD-De.

LIMITATIONS

Publication/measurement bias; exploratory nature of the meta-analyses for interventions that included participants solely with TRBD-De.

CONCLUSIONS

Overall, a few interventions are available for TRBD, including pramipexole, ECT, and clozapine, among others. Larger and better-designed trials for TRBD are warranted and should be based on more uniform operational definitions. PROSPERO registration number: CRD42018114567.

Transient effects of multi-infusion ketamine augmentation on treatment-resistant depressive symptoms in patients with treatment-resistant bipolar depression - An open-label three-week pilot study

INTRODUCTION

While the psychiatric benefits of ketamine have been verified through clinical trials, there is limited information about ketamine augmentation in patients with treatment-resistant bipolar depression (TRBPD). Hence, in the present study, we investigate the therapeutic efficacy and functional brain alterations associated with multi-infusion ketamine augmentation in patients with TRBPD.

METHODS

The present three-week study included 38 patients with TRBPD, all of whom received a series of nine ketamine injections over the study period. The Hamilton Depression Rating Scale (HAMD) was used to assess the effects of multi-infusion ketamine combined with mood stabilizers. Brain function was evaluated by global functional connectivity density (gFCD).

RESULTS

Adjunctive treatment with multiple infusions of ketamine, when combined with a mood stabilizer, could effectively alleviate depressive symptoms for one week, yet the symptoms began to relapse during the second week. Functional brain alterations were detected via gFCD. Specifically, gFCD reductions were mainly found in the bilateral insula, right caudate nucleus, and bilateral inferior frontal gyrus, while increased gFCD was mainly located in the bilateral postcentral gyrus, subgenual anterior cingulate cortex, bilateral thalamus, and cerebellum. Although gFCD alterations were sustained for up to three weeks after the first ketamine infusion, the antidepressant effects of ketamine augmentation sharply declined from the end of the second week of treatment.

CONCLUSIONS

Multi-infusion ketamine augmentation can rapidly alleviate depressive symptoms in patients with TRBPD. The clinical effects were primarily visible in the first week after treatment and partially sustained for two weeks; however, the therapeutic effects and related functional brain alterations sharply decreased from the end of the second week. Based on these findings, we demonstrated that the clinical efficacy and functional brain alterations induced by ketamine augmentation are transient.

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.

Augmentative Repetitive Transcranial Magnetic Stimulation (rTMS) in the Acute Treatment of Poor Responder Depressed Patients: A Comparison Study Between High and Low Frequency Stimulation

Background:

While the efficacy of repetitive transcranial magnetic stimulation (rTMS) in Major Depressive Disorder (MDD) is well established, the debate is still open in relation to bipolar depression and to a possible different effectiveness of high vs. low stimulation. The present study was aimed to assess and compare the efficacy and tolerability of different protocols of augmentative rTMS in a sample of patients with current Major Depressive Episode (MDE), poor drug response/treatment resistance and a diagnosis of MDD or bipolar disorder.

Methods:

Thirty-three patients were recruited in a 4-week, blind-rater, rTMS trial and randomised to the following three groups of stimulation: (1) (n = 10) right dorsolateral prefrontal cortex (DLPFC) 1 HZ, 110% of the motor threshold (MT), 420 stimuli/day; (2) (n = 10) right DLPFC, 1 Hz, 110% MT, 900 stimuli/day; (3) (n = 13) left DLPFC, 10 Hz, 80% MT, 750 stimuli/day.

Results:

Twenty-nine patients completed the treatment, showing a significant reduction of primary outcome measures (HAM-D, MADRS and CGI-S total scores: t = 8.1, P < 0.001; t = 8.6, P < 0.001; t = 4.6, P < 0.001 respectively). No significant differences in terms of efficacy and tolerability were found between high vs. low frequency and between unipolar and bipolar patients. Side effects were reported by 21% of the sample. One of the 4 dropouts was caused by a hypomanic switch.

Conclusions:

Augmentative rTMS appeared to be effective and well tolerated for the acute treatment of unipolar and bipolar depression with features of poor drug response/treatment resistance, showing a comparable effectiveness profile between protocols of high and low frequency stimulation.

Disturbance of Oxidative Stress Parameters in Treatment-Resistant Bipolar Disorder and Their Association With Electroconvulsive Therapy Response

OBJECTIVE

Electroconvulsive therapy (ECT) is an effective option for treatment-resistant bipolar disorder (trBD). However, the mechanisms of its effect are unknown. Oxidative stress is thought to be involved in the underpinnings of BD. Our study is the first, to our knowledge, to report the association between notable oxidative stress parameters (superoxide dismutase [SOD], glutathione peroxidase [GSH-Px], catalase [CAT], and malondialdehyde [MDA]) levels and ECT response in trBD patients.

METHODS

A total 28 trBD patients and 49 controls were recruited. Six-week ECT and naturalistic follow-up were conducted. SOD, GSH-Px, CAT, and MDA levels were measured by enzyme-linked immunosorbent assay, and the 17-item Hamilton Depression Rating Scale and Young Mania Rating Scale were administered at baseline and the end of the 6th week. MANCOVA, ANCOVA, 2 × 2 ANCOVA, and a multiple regression model were conducted.

RESULTS

SOD levels were lower in both trBD mania and depression (P = .001; P = .001), while GSH-Px (P = .01; P = .001) and MDA (P = .001; P = .001) were higher in both trBD mania and depression compared with controls. CAT levels were positively associated with 17-item Hamilton Depression Rating Scale scores in trBD depression (radjusted  = 0.83, P = .005). MDA levels in trBD decreased after 6 weeks of ECT (P = .001). Interestingly, MDA levels decreased in responders (P = .001) but not in nonresponders (P > .05).

CONCLUSIONS

Our study indicates that decreased SOD could be a trait rather than a state in trBD. Oxidative stress levels are associated with illness severity and ECT response. This suggests that the mechanism of oxidative stress plays a crucial role in the pathophysiology of trBD.

Treatment-resistant and multi-therapy-resistant criteria for bipolar depression: consensus definition

BACKGROUND

Most people with bipolar disorder spend a significant percentage of their lifetime experiencing either subsyndromal depressive symptoms or major depressive episodes, which contribute greatly to the high levels of disability and mortality associated with the disorder. Despite the importance of bipolar depression, there are only a small number of recognised treatment options available. Consecutive treatment failures can quickly exhaust these options leading to treatment-resistant bipolar depression (TRBD). Remarkably few studies have evaluated TRBD and those available lack a comprehensive definition of multi-therapy-resistant bipolar depression (MTRBD).AimsTo reach consensus regarding threshold definitions criteria for TRBD and MTRBD.

METHOD

Based on the evidence of standard treatments available in the latest bipolar disorder treatment guidelines, TRBD and MTRBD criteria were agreed by a representative panel of bipolar disorder experts using a modified Delphi method.

RESULTS

TRBD criteria in bipolar depression was defined as failure to reach sustained symptomatic remission for 8 consecutive weeks after two different treatment trials, at adequate therapeutic doses, with at least two recommended monotherapy treatments or at least one monotherapy treatment and another combination treatment. MTRBD included the same initial definition as TRBD, with the addition of failure of at least one trial with an antidepressant, a psychological treatment and a course of electroconvulsive therapy.

CONCLUSIONS

The proposed TRBD and MTRBD criteria may provide an important signpost to help clinicians, researchers and stakeholders in judging how and when to consider new non-standard treatments. However, some challenging diagnostic and therapeutic issues were identified in the consensus process that need further evaluation and research.Declaration of interestIn the past 3 years, M.B. has received grant/research support from the NIH, Cooperative Research Centre, Simons Autism Foundation, Cancer Council of Victoria, Stanley Medical Research Foundation, MBF, NHMRC, Beyond Blue, Rotary Health, Geelong Medical Research Foundation, Bristol Myers Squibb, Eli Lilly, Glaxo SmithKline, Meat and Livestock Board, Organon, Novartis, Mayne Pharma, Servier, Woolworths, Avant and the Harry Windsor Foundation, has been a speaker for Astra Zeneca, Bristol Myers Squibb, Eli Lilly, Glaxo SmithKline, Janssen Cilag, Lundbeck, Merck, Pfizer, Sanofi Synthelabo, Servier, Solvay and Wyeth and served as a consultant to Allergan, Astra Zeneca, Bioadvantex, Bionomics, Collaborative Medicinal Development, Eli Lilly, Grunbiotics, Glaxo SmithKline, Janssen Cilag, LivaNova, Lundbeck, Merck, Mylan, Otsuka, Pfizer and Servier. A.C. has received fees for lecturing from pharmaceutical companies namely Lundbeck and Sunovion. A.J.C. has in the past 3 years received honoraria for speaking from Astra Zeneca and Lundbeck, honoraria for consulting from Allergan, Janssen, Lundbeck and LivaNova and research grant support from Lundbeck. G.M.G. holds shares in P1Vital and has served as consultant, advisor or CME speaker for Allergan, Angelini, Compass pathways, MSD, Lundbeck, Otsuka, Takeda, Medscape, Minervra, P1Vital, Pfizer, Servier, Shire and Sun Pharma. J.G. has received research funding from National Institute for Health Research, Medical Research Council, Stanley Medical Research Institute and Wellcome. H.G. received grants/research support, consulting fees or honoraria from Gedeon Richter, Genericon, Janssen Cilag, Lundbeck, Otsuka, Pfizer and Servier. R.H.M.-W. has received support for research, expenses to attend conferences and fees for lecturing and consultancy work (including attending advisory boards) from various pharmaceutical companies including Astra Zeneca, Cyberonics, Eli Lilly, Janssen, Liva Nova, Lundbeck, MyTomorrows, Otsuka, Pfizer, Roche, Servier, SPIMACO and Sunovion. R.M. has received research support from Big White Wall, Electromedical Products, Johnson and Johnson, Magstim and P1Vital. S.N. received honoraria from Lundbeck, Jensen and Otsuka. J.C.S. has received funds for research from Alkermes, Pfizer, Allergan, J&amp;J, BMS and been a speaker or consultant for Astellas, Abbott, Sunovion, Sanofi. S.W has, within the past 3 years, attended advisory boards for Sunovion and LivaNova and has undertaken paid lectures for Lundbeck. D.J.S. has received honoraria from Lundbeck. T.S. has reported grants from Pathway Genomics, Stanley Medical Research Institute and Palo Alto Health Sciences; consulting fees from Sunovion Pharamaceuticals Inc.; honoraria from Medscape Education, Global Medical Education and CMEology; and royalties from Jones and Bartlett, UpToDate and Hogrefe Publishing. S.P. has served as a consultant or speaker for Janssen, and Sunovion. P.T. has received consultancy fees as an advisory board member from the following companies: Galen Limited, Sunovion Pharmaceuticals Europe Ltd, myTomorrows and LivaNova. E.V. received grants/ research support, consulting fees or honoraria from Abbott, AB-Biotics, Allergan, Angelini, Dainippon Sumitomo, Ferrer, Gedeon Richter, Janssen, Lundbeck, Otsuka and Sunovion. L.N.Y. has received grants/research support, consulting fees or honoraria from Allergan, Alkermes, Dainippon Sumitomo, Janssen, Lundbeck, Otsuka, Sanofi, Servier, Sunovion, Teva and Valeant. A.H.Y. has undertaken paid lectures and advisory boards for all major pharmaceutical companies with drugs used in affective and related disorders and LivaNova. He has also previously received funding for investigator-initiated studies from AstraZeneca, Eli Lilly, Lundbeck and Wyeth. P.R.A.S. has received research funding support from Corcept Therapeutics Inc. Corcept Therapeutics Inc fully funded attendance at their internal conference in California USA and all related expenses. He has received grant funding from the Medical Research Council UK for a collaborative study with Janssen Research and Development LLC. Janssen Research and Development LLC are providing non-financial contributions to support this study. P.R.A.S. has received a presentation fee from Indivior and an advisory board fee from LivaNova.

Na+, K+-ATPase inhibition causes hyperactivity and impulsivity in mice via dopamine D2 receptor-mediated mechanism

Hyperactivity and impulsivity are common symptoms in several psychiatric disorders. Although dysfunction of Na⁺, K⁺-ATPase has been reported to be associated with the psychiatric disorders, it is not clear whether inhibition of Na⁺, K⁺-ATPase causes behavioral effects, including hyperactivity and impulsivity, in mice. Here, we evaluated the effect of intracerebroventricular (icv) injection of ouabain, an inhibitor of Na⁺, K⁺-ATPase, on hyperactivity and impulsivity in mice. At seven days after icv injection, ouabain-injected mice displayed the increase in the distance traveled in the open field arena in the open field test and the increase in the number of head-dipping behavior in the cliff avoidance test. Chlorpromazine or haloperidol, typical antipsychotics, reduced the hyperactivity and impulsivity in ouabain-injected mice. On the other hand, neither lithium carbonate nor valproate, established mood-stabilizing drugs, improved hyperactivity and impulsivity in our mouse model. Furthermore, ouabain-injected mice exhibited the increase in the number of c-fos-positive cells in the nucleus accumbens and the prefrontal cortex but not in the ventral tegmental area, which was reduced by haloperidol. These results suggest that the dysfunction of Na⁺, K⁺-ATPase causes hyperactivity and impulsivity via hyperactivation of dopamine D2 receptor-mediated signaling pathway, causing disturbed neuronal circuits in mice.

Ten-year outcome of vagus nerve stimulation-implanted patients with treatment-resistant depression: two Italian cases

Over the last 15 years, vagus nerve stimulation (VNS) has been used as an augmentative therapeutic intervention in patients with treatment-resistant depression (TRD), whether with a lifetime diagnosis of major depressive disorder or bipolar disorder. From being a potentially effective treatment in the acute phase of TRD, recently published treatment guidelines seemed to converge on the indication that VNS's greatest benefit may be seen mostly beyond the short term. However, with the exception of a recent multicenter American report, very few studies have assessed the long-term efficacy of VNS in TRD patients. Herein, we present the cases of two Italian patients with TRD, with 10-year VNS follow-up evaluation. Both patients were found to benefit from augmentative VNS, and the latency of their stimulation response, tolerability, associated pharmacological treatment, number and duration of recurrences, and overall level of functioning are described and discussed. Further reports with larger samples are needed to support the long-term efficacy and tolerability of VNS in TRD patients, particularly beyond 5 years of follow-up.

Brain stimulation treatments in bipolar disorder: A review of the current literature

OBJECTIVES

Brain stimulation techniques are non-pharmacologic strategies which offer additional therapeutic options for treatment-resistant depression (TRD). The purpose of this paper is to review the current literature regarding the use of brain stimulation in resistant bipolar disorder (BD), with particular reference to hypomanic/manic symptoms.

METHODS

Keywords pertaining to the brain simulation techniques used in the treatment of depression (either unipolar or bipolar) along with their role in regard to hypomanic/manic symptoms were used to conduct an electronic search of the literature. Pertinent findings were identified by the authors and reviewed.

RESULTS

Brain stimulation techniques represent a valid therapeutic option in TRD. They have been extensively studied in unipolar depression and, to a minor extent, in the depressive phase of BD, showing encouraging but often limited results. With exception of electroconvulsive therapy, the efficacy of brain stimulation in the treatment of manic symptoms of bipolar patients is still uncertain and needs to be fully evaluated.

CONCLUSIONS

Brain stimulation in BD is derived from its use in unipolar depression. However, there are many important differences between these two disorders and more studies with a systematic approach need to be conducted on larger samples of bipolar patients with treatment-resistant characteristics.

Pharmacological Approaches for Treatment-resistant Bipolar Disorder

Bipolar disorder is prevalent, with high risks of disability, substance abuse and premature mortality. Treatment responses typically are incomplete, especially for depressive components, so that many cases can be considered “treatment resistant.” We reviewed reports on experimental treatments for such patients: there is a striking paucity of such research, mainly involving small incompletely controlled trials of add-on treatment, and findings remain preliminary. Encouraging results have been reported by adding aripiprazole, bupropion, clozapine, ketamine, memantine, pramipexole, pregabalin, and perhaps tri-iodothyronine in resistant manic or depressive phases. The urgency of incomplete responses in such a severe illness underscores the need for more systematic, simpler, and better controlled studies in more homogeneous samples of patients.

Royal Australian and New Zealand College of Psychiatrists clinical practice guidelines for mood disorders

OBJECTIVES

To provide guidance for the management of mood disorders, based on scientific evidence supplemented by expert clinical consensus and formulate recommendations to maximise clinical salience and utility.

METHODS

Articles and information sourced from search engines including PubMed and EMBASE, MEDLINE, PsycINFO and Google Scholar were supplemented by literature known to the mood disorders committee (MDC) (e.g., books, book chapters and government reports) and from published depression and bipolar disorder guidelines. Information was reviewed and discussed by members of the MDC and findings were then formulated into consensus-based recommendations and clinical guidance. The guidelines were subjected to rigorous successive consultation and external review involving: expert and clinical advisors, the public, key stakeholders, professional bodies and specialist groups with interest in mood disorders.

RESULTS

The Royal Australian and New Zealand College of Psychiatrists clinical practice guidelines for mood disorders (Mood Disorders CPG) provide up-to-date guidance and advice regarding the management of mood disorders that is informed by evidence and clinical experience. The Mood Disorders CPG is intended for clinical use by psychiatrists, psychologists, physicians and others with an interest in mental health care.

CONCLUSIONS

The Mood Disorder CPG is the first Clinical Practice Guideline to address both depressive and bipolar disorders. It provides up-to-date recommendations and guidance within an evidence-based framework, supplemented by expert clinical consensus.

MOOD DISORDERS COMMITTEE

Professor Gin Malhi (Chair), Professor Darryl Bassett, Professor Philip Boyce, Professor Richard Bryant, Professor Paul Fitzgerald, Dr Kristina Fritz, Professor Malcolm Hopwood, Dr Bill Lyndon, Professor Roger Mulder, Professor Greg Murray, Professor Richard Porter and Associate Professor Ajeet Singh.

INTERNATIONAL EXPERT ADVISORS

Professor Carlo Altamura, Dr Francesco Colom, Professor Mark George, Professor Guy Goodwin, Professor Roger McIntyre, Dr Roger Ng, Professor John O'Brien, Professor Harold Sackeim, Professor Jan Scott, Dr Nobuhiro Sugiyama, Professor Eduard Vieta, Professor Lakshmi Yatham.

AUSTRALIAN AND NEW ZEALAND EXPERT ADVISORS

Professor Marie-Paule Austin, Professor Michael Berk, Dr Yulisha Byrow, Professor Helen Christensen, Dr Nick De Felice, A/Professor Seetal Dodd, A/Professor Megan Galbally, Dr Josh Geffen, Professor Philip Hazell, A/Professor David Horgan, A/Professor Felice Jacka, Professor Gordon Johnson, Professor Anthony Jorm, Dr Jon-Paul Khoo, Professor Jayashri Kulkarni, Dr Cameron Lacey, Dr Noeline Latt, Professor Florence Levy, A/Professor Andrew Lewis, Professor Colleen Loo, Dr Thomas Mayze, Dr Linton Meagher, Professor Philip Mitchell, Professor Daniel O'Connor, Dr Nick O'Connor, Dr Tim Outhred, Dr Mark Rowe, Dr Narelle Shadbolt, Dr Martien Snellen, Professor John Tiller, Dr Bill Watkins, Dr Raymond Wu.

Clozapine for treatment-resistant bipolar disorder: a systematic review

OBJECTIVE

To evaluate the efficacy and safety of clozapine for treatment-resistant bipolar disorder (TRBD).

METHODS

A systematic review of randomized controlled studies, open-label prospective studies, and retrospective studies of patients with TRBD was carried out. Interventions included clozapine monotherapy or clozapine combined with other medications. Outcome measures were efficacy and adverse drug reactions (ADRs).

RESULTS

Fifteen clinical trials with a total sample of 1,044 patients met the inclusion criteria. Clozapine monotherapy or clozapine combined with other treatments for TRBD was associated with improvement in: (i) symptoms of mania, depression, rapid cycling, and psychotic symptoms, with many patients with TRBD achieving a remission or response; (ii) the number and duration of hospitalizations, the number of psychotropic co-medications, and the number of hospital visits for somatic reasons for intentional self-harm/overdose; (iii) suicidal ideation and aggressive behavior; and (iv) social functioning. In addition, patients with TRBD showed greater clinical improvement in long-term follow-up when compared with published schizophrenia data. Sedation (12%), constipation (5.0%), sialorrhea (5.2%), weight gain (4%), and body ache/pain (2%) were the commonly reported ADRs; however, these symptoms but did not usually require drug discontinuation. The percentage of severe ADRs reported, such as leukopenia (2%), agranulocytosis (0.3%), and seizure (0.5%), appeared to be lower than those reported in the published schizophrenia literature.

CONCLUSION

The limited current evidence supports the concept that clozapine may be both an effective and a relatively safe medication for TRBD.

Maintenance Deep Transcranial Magnetic Stimulation Sessions are Associated with Reduced Depressive Relapses in Patients with Unipolar or Bipolar Depression

Introduction: Deep transcranial magnetic stimulation (dTMS) is a new form of TMS allowing safe stimulation of deep brain regions. The objective of this preliminary study was to assess the role of dTMS maintenance sessions in protecting patients with bipolar disorder (BD) or recurrent major depressive disorder (MDD) from developing depressive or manic relapses in a 12-month follow-up period.

Methods: Twenty-four drug-resistant patients with a current depressive episode and a diagnosis of MDD or BD have been enrolled in the study. All the participants underwent daily dTMS sessions for 4 weeks. One group (maintenance – M group) received additional maintenance dTMS sessions weekly or twice a week.

Results: After the first dTMS cycle, a significant reduction of Hamilton Depression Rating Scale (HDRS) scores was observed in all participants. Subsequently, the HDRS mean scores did not significantly change over time in the M group, while it significantly increased in the non-M-group after 6 and 12 months.

Discussion: This study confirms previous evidence of a positive therapeutic effect of dTMS on depressive symptoms and suggests that, after recovery from acute episodes, maintenance dTMS sessions may be helpful in maintaining euthymia in a 12-month follow-up period.

Unexplored areas of psychotherapy in bipolar disorder

Several psychological interventions-including group psychoeducation, family-focused psychoeducation, and interpersonal social-rhythm therapy-have demonstrated prophylactic efficacy as an adjunct to medication in bipolar disorders (BDs). The field of psychological interventions for BD has experienced impressive progress over the last 15 years. Certain unexplored areas, however, require further research in order to establish the full potential of psychological interventions for BD. Such research should focus, among other things, on cognitive impairment associated with BD, BD in the elderly, comorbid anxiety disorders and other comorbidities, the treatment of BD in pregnant women, and the improvement of patients' overall physical health.

Electroconvulsive therapy improves clinical manifestation with plasma BDNF levels unchanged in treatment-resistant depression patients

Electroconvulsive therapy (ECT) is the most effective treatment in treatment-resistant depression; it may modulate intracellular processes in such patients. This study aimed to investigate the association between changes in plasma brain-derived neurotrophic factor (BDNF) levels and the clinical improvements after ECT for patients with treatment-resistant depression. Fifty-five inpatients with treatment-resistant depression were recruited. The severity of depression was measured using the 17-item Hamilton Rating Scale for Depression (HAMD-17) and the Clinical Global Impression-Severity (CGI-S) before ECT, after every 3 sessions of ECT, and at the end of ECT. Plasma BDNF levels were measured in all subjects before and after ECT. The severity of depression was significantly reduced on the HAMD-17 (p < 0.001) and the CGI-S (p < 0.001) after the end of ECT. There were no significant differences in plasma BDNF levels after ECT (p = 0.615). No significant correlation was found between changes in plasma BDNF levels and changes in HAMD-17 scores (r = 0.188, p = 0.169). Our results do not support the hypothesis that improvements in treatment-resistant depression patients after ECT are due to changes in BDNF levels.

Options for pharmacological treatment of refractory bipolar depression

Bipolar disorders of types I and II, even when treated by currently standard options, show a marked excess of depressive morbidity. Treated, type I patients in mid-course or from the onset of illness are ill, overall, 50 % of weeks of follow-up, and 75 % of that unresolved morbidity is depressive. Currently widely held impressions are that bipolar depression typically is poorly responsive to antidepressants, that treatment-resistant depression (TRD) is characteristic of the disorder, and that risk of mania with antidepressant treatment is very high. However, none of these views is supported consistently by available research. TRD may be more prevalent in bipolar than unipolar mood disorders. Relatively intense research attention is directed toward characteristics and treatments of TRD in unipolar depression, but studies of bipolar TRD are uncommon. We found only five controlled trials, plus 10 uncontrolled trials, providing data on a total of 13 drug treatments, all of which involved one or two trials, in 87 % as add-ons to complex, uncontrolled regimens. In two controlled trials, ketamine was superior to placebo but it is short-acting and not orally active; pramipexole was weakly superior to placebo in one controlled trial; three other drugs failed to outperform controls. Other pharmacotherapies are inadequately evaluated and nonpharmacological options are virtually untested in bipolar TRD. The available research supports the view that antidepressants may be effective in bipolar depression provided that currently agitated patients are excluded, that risk of mania with antidepressants is only moderately greater than risk of spontaneous mania, and that bipolar TRD is not necessarily resistant to all treatments.

The International Society for Bipolar Disorders (ISBD) task force report on antidepressant use in bipolar disorders

OBJECTIVE

The risk-benefit profile of antidepressant medications in bipolar disorder is controversial. When conclusive evidence is lacking, expert consensus can guide treatment decisions. The International Society for Bipolar Disorders (ISBD) convened a task force to seek consensus recommendations on the use of antidepressants in bipolar disorders.

METHOD

An expert task force iteratively developed consensus through serial consensus-based revisions using the Delphi method. Initial survey items were based on systematic review of the literature. Subsequent surveys included new or reworded items and items that needed to be rerated. This process resulted in the final ISBD Task Force clinical recommendations on antidepressant use in bipolar disorder.

RESULTS

There is striking incongruity between the wide use of and the weak evidence base for the efficacy and safety of antidepressant drugs in bipolar disorder. Few well-designed, long-term trials of prophylactic benefits have been conducted, and there is insufficient evidence for treatment benefits with antidepressants combined with mood stabilizers. A major concern is the risk for mood switch to hypomania, mania, and mixed states. Integrating the evidence and the experience of the task force members, a consensus was reached on 12 statements on the use of antidepressants in bipolar disorder.

CONCLUSIONS

Because of limited data, the task force could not make broad statements endorsing antidepressant use but acknowledged that individual bipolar patients may benefit from antidepressants. Regarding safety, serotonin reuptake inhibitors and bupropion may have lower rates of manic switch than tricyclic and tetracyclic antidepressants and norepinephrine-serotonin reuptake inhibitors. The frequency and severity of antidepressant-associated mood elevations appear to be greater in bipolar I than bipolar II disorder. Hence, in bipolar I patients antidepressants should be prescribed only as an adjunct to mood-stabilizing medications.

Longitudinal course of symptom severity and fluctuation in patients with treatment-resistant unipolar and bipolar depression

Little is currently known about the long-term course of symptom severity and fluctuation in patients with treatment-resistant depression (TRD). We assessed this using the longitudinal interval follow-up evaluation in 115 patients with TRD (84 unipolar, 31 bipolar) with 1-7 years (median 36 months) of follow-up. Of the follow-up months, 39.2% were spent asymptomatic and 21.1% at sub-threshold symptom level, while 15.8% were spent at mild, 13.9% at moderate, and 10.0% at severe depressive episode level. Significantly more unipolar than bipolar patients were continuously symptomatic during follow-up (43% vs. 29%). Patients had a mean of 1.0 (S.D.=1.2) symptom severity level fluctuations per year. High fluctuating patients had significantly poorer global functioning and quality of life. Although most patients with TRD achieve an asymptomatic state, they continue to fluctuate and experience depressive symptoms in the majority of months, mostly at subclinical or mild severity. However, there are important differences between unipolar and bipolar TRD, with unipolar patients more likely to experience an unremitting depressive state. Additionally, a more fluctuating longitudinal illness course is associated with poorer function and quality of life, and with a bipolar diagnosis. We suggest that the longitudinal illness course is an important outcome to be considered in future TRD research.

Evidence-based treatment strategies for treatment-resistant bipolar depression: a systematic review

OBJECTIVES

Treatment resistance in bipolar depression is a common clinical problem that constitutes a major challenge for the treating clinician as there is a paucity of treatment options. The objective of this paper was to review the evidence for treatment options in treatment-resistant bipolar depression, as found in randomized controlled trials and with special attention to the definition and assessment of treatment resistance.

METHODS

A Medline search (from database inception to May 2012) was performed using the search terms treatment resistance or treatment refractory, and bipolar depression or bipolar disorder, supplemented with 43 separate searches using the various pharmacologic agents or technical interventions as search terms.

RESULTS

Only seven studies met our inclusion criteria. These studies examined the effects of ketamine (n = 1), (ar)modafinil (n = 2), pramipexole (n = 1), lamotrigine (n = 1), inositol (n = 1), risperidone (n = 1), and electroconvulsive therapy (ECT) (n = 2).

CONCLUSIONS

The available level I evidence for treatment strategies in resistant bipolar depression is extremely scarce, and although the response rates reported are reassuring, most of the strategies remain experimental. There is an urgent need for further study in homogeneous patient samples using a clear concept of treatment resistance.

Deep transcranial magnetic stimulation for treatment-resistant bipolar depression: a case report of acute and maintenance efficacy

Deep Transcranial Magnetic Stimulation (dTMS) is currently being evaluated as a possible treatment for several neuropsychiatric disorders and has been demonstrated as a safe and effective procedure. This case presents a patient with bipolar depression that has been treated with 20 daily consecutive dTMS sessions and with one dTMS session every 2 weeks for the following 3 months. Depressive symptoms improved rapidly and response was maintained during the next 6 months; cognitive performances also improved. This report suggests that add-on dTMS may help overcoming drug-resistance in bipolar depression and protect from subsequent bipolar episodes of any polarity.

Clinical factors leading to lamotrigine prescription in bipolar outpatients: subanalysis of the SIN-DEPRES study

BACKGROUND

The use of lamotrigine is a point of discrepancy among the diverse guidelines published on the management of bipolar disorder (BD). Evidence supporting the long-term efficacy is reasonably robust. Nonetheless, the effectiveness of lamotrigine in acute treatment is vigorously debated and it is unclear how this drug is used in routine clinical practice. This subanalysis of the SIN-DEPRES study was designed to understand the clinical profile of bipolar patients receiving lamotrigine.

METHODS

In this prospective national multicenter study, 652 patients with clinically stable bipolar I and II disorder were recruited. Clinical assessments included sociodemographic and clinical data, the Modified Clinical Global Impression scale for BD (CGI-BP-M), the Hamilton Depression Rating Scale (HDRS), and prescriptions of psychotropic medications and their doses.

RESULTS

By means of a logistic regression model, an association between receiving treatment with lamotrigine and the following clinical variables was found: number of past depressive episodes (O.R.=2.875, 95% CI: 1.203-6.869, p=0.018), depressive polarity of the most recent episode (O.R.=1.945, 95% CI: 1.267-2.985, p=0.002), severity in CGI-BD-M depression (O.R.=1.850, 95% CI: 1.215-2.817, p=0.004), bipolar II disorder diagnosis (O.R.=1.635, 95% CI: 1.078-2.482, p=0.021) and number of episodes per year (O.R.=1.310, 95% CI: 1.069-1.605, p=0.009).

LIMITATIONS

Subanalysis of the SIN-DEPRES study with a cross-sectional design.

CONCLUSIONS

The use of lamotrigine in clinical practice is in accordance with most of the guidelines, which support its use in patients with depressive predominant polarity and bipolar II disorder.

The argument of antidepressant drugs in the treatment of bipolar depression: mixed evidence or mixed states?

INTRODUCTION

The role of antidepressant drugs in acute and maintenance treatment of bipolar depression is a matter of debate that cannot be decided from the evidence available in the current literature.

AREAS COVERED

This review includes two sections: in the first, important contributions from the current literature, emphasizing randomized controlled trials (RCTs) and meta-analysis, highlight current controversies and methodological issues; in the second, the impact of mixed depressive features in bipolar depression is evaluated from a psychopathological perspective.

EXPERT OPINION

Methodological issues may complicate evaluation of the evidence from RCTs regarding antidepressants and mixed states. Moreover, nosological constructs may also contribute to the inconclusive findings, by introducing heterogeneity in patient selection and diagnosis. Acknowledging the impact of mixed features in the course of bipolar depression, essentially by the careful reading of classical Kraepelinian contributions, could enhance clinical management. This would in turn allow a more judicious use of antidepressants, ideally helping to shed some light on the much controversial 'antidepressant-related suicidality', and help to further clarify the reasons for the current literature discordance on this topic.

Evidence-based options for treatment-resistant adult bipolar disorder patients

OBJECTIVES

Many patients diagnosed with bipolar disorder (BD) respond incompletely or unsatisfactorily to available treatments. Given the potentially devastating nature of this prevalent disorder, there is a pressing need to improve clinical care of such patients.

METHODS

We performed a literature review of the research findings related to treatment-resistant BD reported through February 2012.

RESULTS

Therapeutic trials for treatment-resistant bipolar mania are uncommon, and provide few promising leads other than the use of clozapine. Far more pressing challenges are the depressive-dysthymic-dysphoric-mixed phases of BD and long-term prophylaxis. Therapeutic trials for treatment-resistant bipolar depression have assessed anticonvulsants, modern antipsychotics, glutamate [N-methyl-D-aspartate (NMDA)] antagonists, dopamine agonists, calcium-channel blockers, and thyroid hormones, as well as behavioral therapy, sleep deprivation, light therapy, electroconvulsive therapy (ECT), transcranial magnetic stimulation, and deep brain stimulation-all of which are promising but limited in effectiveness. Several innovative pharmacological treatments (an anticholinesterase, a glutamine antagonist, a calcium-channel blocker, triiodothyronine, olanzapine and topiramate), ECT, and cognitive-behavior therapy have some support for long-term treatment of resistant BD patients, but most of trials of these treatments have been methodologically limited.

CONCLUSIONS

Most studies identified were small, involved supplementation of typically complex ongoing treatments, varied in controls, randomization, and blinding, usually involved brief follow-up, and lacked replication. Clearer criteria for defining and predicting treatment resistance in BD are needed, as well as improved trial design with better controls, assessment of specific clinical subgroups, and longer follow-up.

Replication of ketamine's antidepressant efficacy in bipolar depression: a randomized controlled add-on trial

BACKGROUND

Currently, no pharmacological treatments for bipolar depression exist that exert rapid (within hours) antidepressant or antisuicidal effects. We previously reported that intravenous administration of the N-methyl-D-aspartate antagonist ketamine produced rapid antidepressant effects in patients with treatment-resistant bipolar depression. The present study sought to replicate this finding in an independent sample.

METHODS

In this double-blind, randomized, crossover, placebo-controlled study, 15 subjects with DSM-IV bipolar I or II depression maintained on therapeutic levels of lithium or valproate received a single intravenous infusion of either ketamine hydrochloride (.5 mg/kg) or placebo on 2 test days 2 weeks apart. The primary outcome measure was the Montgomery-Asberg Depression Rating Scale, which was used to rate overall depressive symptoms at baseline; at 40, 80, 110, and 230 minutes postinfusion; and on days 1, 2, 3, 7, 10, and 14 postinfusion.

RESULTS

Within 40 minutes, depressive symptoms, as well as suicidal ideation, significantly improved in subjects receiving ketamine compared with placebo (d = .89, 95% confidence interval = .61-1.16, and .98, 95% confidence interval = .64-1.33, respectively); this improvement remained significant through day 3. Seventy-nine percent of subjects responded to ketamine and 0% responded to placebo at some point during the trial. The most common side effect was dissociative symptoms, which occurred only at the 40-minute time point.

CONCLUSIONS

This study replicated our previous finding that patients with bipolar depression who received a single ketamine infusion experienced a rapid and robust antidepressant response. In addition, we found that ketamine rapidly improved suicidal ideation in these patients.

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.

Could the underestimation of bipolarity obstruct the search for novel antidepressant drugs?

INTRODUCTION

Despite the clinical and social relevance of depression, and the availability of numerous antidepressants and non-pharmacological interventions, response rates remain unsatisfactory and novel therapeutic targets are being explored.

AREAS COVERED

This review starts with a brief overview of the evolution of the current antidepressant drug scenario and ends with a focus on the potential influence of the underestimation of bipolarity on the exploration of novel antidepressant drugs.

EXPERT OPINION

The field of antidepressant drug development has suffered from a relative decline recently and, with the exception of agomelatine, innovative non-monoaminergic antidepressants have yet to be developed. The need for more effective compounds is evident. Clinicians and researchers should pay greater attention to the impact of bipolarity in depression. The ultimate goal of this review is not to discourage the use of antidepressants but rather to encourage judicious prescriptions, and also to solicit a better collaboration between clinicians and preclinical researchers so that more reliable diagnostic criteria can be adopted.

Therapeutic options in treatment-resistant depression

The phenomenon of treatment-resistant depression (TRD), described as the occurrence of an inadequate response after an adequate treatment with antidepressant agents (in terms of dose, duration, and adherence), is very common in clinical practice. It has been broadly defined in the context of unipolar major depression, but alternative definitions for bipolar depression have also been suggested. In both cases, there is a remarkable lack of consensus amongst professionals concerning its operative definition. A relatively wide variety of treatment options for unipolar TRD are available, whilst the evidence is very scanty for bipolar TRD. TRD is associated to poor clinical, functional, and social outcomes. Several novel therapeutic options are currently being investigated as promising alternatives, targeting the neurotransmitter system outside of the standard monoamine hypothesis. Augmentation or combination with lithium or atypical antipsychotics appears as a valid option for both conditions, and the same occurs with electroconvulsive therapy. Other non-pharmacological strategies such as deep brain stimulation may be promising alternatives for the future. The use of cognitive behaviour therapy is recommended for unipolar TRD, but there is no evidence supporting its use in bipolar TRD.

Factors associated with initial treatment response with antidepressants in bipolar disorder

INTRODUCTION

Controversy in antidepressant (AD) use in bipolar depression relies in its potential induction of mood switches and ineffectiveness. Responders to acute AD add-on treatment maintain response with continued treatment, whilst partial/non-responders fail to reach remission despite continuation treatment. We aimed to identify response predictors to acute AD addition in bipolar depression in order to optimize treatment choice in bipolar depression and avoid unnecessary AD exposure of people unlikely to respond.

METHODS

Two hundred and twenty-one DSM-IV-TR depressed bipolar - type I and II - patients were treated with AD on an observational study. AD response was defined as an at least 50% drop from baseline of their HDRS17 score after 8weeks of treatment. One hundred and thirty-eight patients (138, 62.4%) fulfilled response criteria (RI) whilst 83 patients (37.6%) did not (NRI). In all cases AD therapy was on top of previously prescribed stabilizers and/or atypical antipsychotics.

RESULTS

RI patients were more likely to have had previous response to ADs, whereas NRI had a higher number of previous mood switches with ADs during past depressive episodes. Psychotic symptoms were more frequent amongst RI, whilst lifetime history of atypical depression was more frequent amongst NRI. NRI had more total, depressive, and hypomanic, but not manic or mixed, episodes in the past than RI. Analyzed through a logistic regression, higher previous response to ADs and lower rate of past hypomanic episodes in RI were the variables explaining intergroups (RI vs. NRI) differences.

DISCUSSION

Taking into account the proper caution in the use of Ads in bipolar disorder, there is a subgroup of bipolar patients who might benefit from adjunctive Ads. Looking at specific clinical factors during the course of the illness could help physicians in deciding whether to use an antidepressant in a bipolar depressed patient already treated with mood stabilizers.

New treatment guidelines for acute bipolar depression: a systematic review

INTRODUCTION

Bipolar depression poses a great burden on patients and their families due to its duration, associated functional impairment, and limited treatment options. Given the complexity of the disorder and the advances in treatment, a number of clinical guidelines, consensus statements and expert opinions were developed with the aim to standardize treatment and provide clinicians with treatment algorithms for every-day clinical practice. Unfortunately, they often led to conflicting conclusions and recommendations due to limitations of the available literature. As findings emerge from research literature, guidelines quickly become obsolete and need to be updated or revised. Many guidelines have been updated in the last 5 years, after the last review of bipolar disorder (BD) treatment guidelines.

OBJECTIVE

The purpose of this work is to systematically review guidelines, consensus meetings and treatment algorithms on the acute treatment of bipolar depression updated or published since 2005, to critically underline common and critical points, highlight limits and strengths, and provide a starting point for future research

MATERIALS AND METHODS

The MEDLINe/PubMed/Index Medicus, PsycINFO/PsycLIT, Excerpta Medica/EMBASE, databases were searched using "depression", "bipolar", "manic-depression", "manic-depressive" and "treatment guidelines" as key words

RESULTS

The search returned 204 articles. Amongst them, there were 28 papers concerning structured treatment algorithms and/or guidelines suggested by official panels. After excluding those guidelines that were not performed by scientific societies or international groups and those published before 2005, the final selection yielded 7 papers When looking into guidelines content, the results indicate a trend to the gradual acceptance of the use of the atypical antipsychotic quetiapine as monotherapy as first-line treatment. Antidepressant monotherapy is discouraged in most of them, although some support the use of antidepressants in combination with antimanic agents for a limited period of time. Lamotrigine has become a highly controversial option.

CONCLUSION

The management of bipolar depression is complex and should be differentiated from management of unipolar depression. Guidelines may be useful instruments for helping clinicians to choose and plan bipolar depression treatment by integrating the more updated scientific knowledge with every-day clinical practice and patient-specific factors; however, a further effort is needed in order to improve guidelines implementation in clinical practice. The latest updates on treatment guidelines for bipolar depression give priority to novel treatment approaches, such as quetiapine, over more traditional ones, such as lithium or antidepressants. Lamotrigine is a controversial option.

Antidepressant-resistant depression and antidepressant-associated suicidal behaviour: the role of underlying bipolarity

The complex relationship between the use of antidepressants and suicidal behaviour is one of the hottest topics of our contemporary psychiatry. Based on the literature, this paper summarizes the author's view on antidepressant-resistant depression and antidepressant-associated suicidal behaviour. Antidepressant-resistance, antidepressant-induced worsening of depression, antidepressant-associated (hypo)manic switches, mixed depressive episode, and antidepressant-associated suicidality among depressed patients are relatively most frequent in bipolar/bipolar spectrum depression and in children and adolescents. As early age at onset of major depressive episode and mixed depression are powerful clinical markers of bipolarity and the manic component of bipolar disorder (and possible its biological background) shows a declining tendency with age antidepressant-resistance/worsening, antidepressant-induced (hypo)manic switches and "suicide-inducing" potential of antidepressants seem to be related to the underlying bipolarity.

Efficacy and safety of two treatment algorithms in bipolar depression consisting of a combination of lithium, lamotrigine or placebo and paroxetine

OBJECTIVE

In a previous paper, we reported about the efficacy of the addition of lamotrigine to lithium in patients with bipolar depression. In the second phase of this study paroxetine was added to ongoing treatment in non-responders.

METHOD

Bipolar depressed patients (n = 124) treated with lithium were randomized to addition of lamotrigine or placebo. In non-responders after 8 weeks, paroxetine 20 mg was added for another 8 weeks to ongoing treatment.

RESULTS

After 8 weeks the improvement in patients treated with lamotrigine vs. patients treated with placebo was significant. After addition of paroxetine this difference disappeared as a result of greater further improvement in the non-responders to placebo.

CONCLUSION

Addition of lamotrigine to lithium was found effective in bipolar depressed patients. Further addition of paroxetine in non-responders to lithium plus lamotrigine did not appear to provide additional benefit, while it appeared to do so in non-responders to lithium plus placebo.

Current nosology of treatment resistant depression: a controversy resistant to revision

Treatment-Resistant Depression (TRD) represents a source of ongoing clinical and nosological controversy and confusion. While no univocal consensus on its definition and specific correlation with major mood disorders has been reached to date, a progressively greater number of evidences tend to suggest a revision of current clinical nosology. Since a better assessment of TRD should be considered mandatory in order to achieve the most appropriate clinical management, this narrative review aims to briefly present current most accepted definitions of the phenomenon, speculating on its putative bipolar diathesis for some of the cases originally assessed as unipolar depression.