Mirtazapine augmentation in the treatment of refractory depression

Psychedelic-Induced Serotonin 2A Receptor Downregulation Does Not Predict Swim Stress Coping in Mice

Serotoninergic psychedelics such as psilocybin have been reported to elicit a long-lasting reduction in depressive symptoms. Although the main target for serotoninergic psychedelics, serotonin type 2A receptor (5-HT_2A), has been established, the possible mechanism of the antidepressant action of psychedelics remains unknown. Using the mouse forced swim test model, we examined whether the administration of the synthetic serotoninergic psychedelic 2,5-dimethoxy-4-iodoamphetamine (DOI) would modulate 5-HT_2A receptor levels in the medial prefrontal cortex (mPFC) and revert stress-induced changes in behavior. Mice subjected to swim stress developed a passive stress-coping strategy when tested in the forced swim test 6 days later. This change in behavior was not associated with the hypothesized increase in 5-HT_2A receptor-dependent head twitch behaviors or consistent changes in 5-HT_2A receptor levels in the mPFC. When DOI was administered 1 day before the forced swim test, a low dose (0.2 mg/kg i.p.) unexpectedly increased immobility while a high dose (2 mg/kg i.p.) had no significant effect on immobility. Nevertheless, DOI evoked a dose-dependent decrease in 5-HT_2A levels in the mPFC of mice previously exposed to swim stress. Our findings do not support the hypothesis that the downregulation of 5-HT_2A receptors in the mPFC contributes to the antidepressant-like properties of serotoninergic psychedelics.

Psychopharmacological properties and therapeutic profile of the antidepressant venlafaxine

Major depression (MD) is one of the most common psychiatric disorders worldwide. Currently, the first-line treatment for MD targets the serotonin system but these drugs, notably the selective serotonin reuptake inhibitors, usually need 4 to 6 weeks before the benefit is felt and a significant proportion of patients shows an unsatisfactory response. Numerous treatments have been developed to circumvent these issues as venlafaxine, a mixed serotonin-norepinephrine reuptake inhibitor that binds and blocks both the SERT and NET transporters. Despite this pharmacological profile, it is difficult to have a valuable insight into its ability to produce more robust efficacy than single-acting agents. In this review, we provide an in-depth characterization of the pharmacological properties of venlafaxine from in vitro data to preclinical and clinical efficacy in depressed patients and animal models of depression to propose an indirect comparison with the most common antidepressants. Preclinical studies show that the antidepressant effect of venlafaxine is often associated with an enhancement of serotonergic neurotransmission at low doses. High doses of venlafaxine, which elicit a concomitant increase in 5-HT and NE tone, is associated with changes in different forms of plasticity in discrete brain areas. In particular, the hippocampus appears to play a crucial role in venlafaxine-mediated antidepressant effects notably by regulating processes such as adult hippocampal neurogenesis or the excitatory/inhibitory balance. Overall, depending on the dose used, venlafaxine shows a high efficacy on depressive-like symptoms in relevant animal models but to the same extent as common antidepressants. However, these data are counterbalanced by a lower tolerance. In conclusion, venlafaxine appears to be one of the most effective treatments for treatment of major depression. Still, direct comparative studies are warranted to provide definitive conclusions about its superiority.

Depression

Most psychiatric care is delivered in primary care settings, where depression is the most common presenting psychiatric symptom. Given the high prevalence of depression worldwide and the well-established consequences of untreated depression, the ability of primary care clinicians to effectively diagnose and treat it is critically important. This article offers up-to-date guidance for the diagnosis and treatment of major depressive disorder, including practical considerations for delivering optimal and efficient care for these patients.

The Psychopharmacology Algorithm Project at the Harvard South Shore Program: An Update on Unipolar Nonpsychotic Depression

BACKGROUND

The Psychopharmacology Algorithm Project at the Harvard South Shore Program presents evidence-based recommendations considering efficacy, tolerability, safety, and cost. Two previous algorithms for unipolar nonpsychotic depression were published in 1993 and 1998. New studies over the last 20 years suggest that another update is needed.

METHODS

The references reviewed for the previous algorithms were reevaluated, and a new literature search was conducted to identify studies that would either support or alter the previous recommendations. Other guidelines and algorithms were consulted. We considered exceptions to the main algorithm, as for pregnant women and patients with anxious distress, mixed features, or common medical and psychiatric comorbidities.

SUMMARY

For inpatients with severe melancholic depression and acute safety concerns, electroconvulsive therapy (or ketamine if ECT refused or ineffective) may be the first-line treatment. In the absence of an urgent indication, we recommend trialing venlafaxine, mirtazapine, or a tricyclic antidepressant. These may be augmented if necessary with lithium or T3 (triiodothyronine). For inpatients with non-melancholic depression and most depressed outpatients, sertraline, escitalopram, and bupropion are reasonable first choices. If no response, the prescriber (in collaboration with the patient) has many choices for the second trial in this algorithm because there is no clear preference based on evidence, and there are many individual patient considerations to take into account. If no response to the second medication trial, the patient is considered to have a medication treatment-resistant depression. If the patient meets criteria for the atypical features specifier, a monoamine oxidase inhibitor could be considered. If not, reconsider (for the third trial) some of the same options suggested for the second trial. Some other choices can also considered at this stage. If the patient has comorbidities such as chronic pain, obsessive-compulsive disorder, attention-deficit/hyperactivity disorder, or posttraumatic stress disorder, the depression could be secondary; evidence-based treatments for those disorders would then be recommended.

How do community-based eye care practitioners approach depression in patients with low vision? A mixed methods study

BACKGROUND

Clinically significant depressive symptoms are prevalent in people attending low vision clinics and often go undetected. The Low Vision Service Wales (LVSW) plans to introduce depression screening and management pathways. Prior to implementation there is an unmet need to understand how eye care practitioners providing the service currently address depression with patients, and the characteristics and beliefs that influence their practice.

METHODS

A mixed methods convergent design was employed. Twelve low vision practitioners were purposively selected to engage in individual semi-structured interviews which were analysed using thematic analysis. A further 167 practitioners were invited to complete a questionnaire assessing professional background, current practice, confidence and perceived barriers in working with people with low vision and suspected depression. Multiple regression analyses were performed to determine the characteristics related to the Rasch-transformed questionnaire scores.

RESULTS

Of the 122 practitioners that responded to the questionnaire, 33% aimed to identify depression in patients, and those who were more confident were more likely to do so. Those who scored higher on the perceived barriers scale and lower on confidence were less likely to report acting in response to suspected depression (all p < 0.05). Three qualitative themes were identified; depression is an understandable response to low vision, patients themselves are a barrier to addressing depression and practitioners lacked confidence in their knowledge and skills to address depression. The qualitative data largely expanded the quantitative findings.

CONCLUSIONS

Practitioners viewed their own lack of knowledge and confidence as a barrier to the identification and management of depression and expressed a need for training prior to the implementation of service changes. The study findings will help to inform the development of a training programme to support low vision practitioners and those working with other chronic illness in Wales, and internationally, in the identification and management of people with depression.

Phytochemistry and pharmacology of anti-depressant medicinal plants: A review

Stress renders an individual to experience mental pressure and exhaustion which brings about feelings of anxiety, depression, anger and/or other negative emotions. Depression affects a person's state of mind, behaviour, health and is often associated with suicide. The use of anti-depressant drugs as therapeutic agents is associated with symptoms such as, delayed onset of action, side-effects, drug-drug and dietary interactions, sexual dysfunction, cardiac toxicity, etc. Thus, there is need to target these issues and improve current treatment options. Medicinal plants have long been used in discovering novel treatment strategies and compounds with promising roles in treating various disease conditions. There has been an increase, worldwide, in the use of medicinal plants and herbs for developing nutraceuticals for treatment of depression and other psychiatric disorders. Medicinal plants in their natural forms are valuable as they are rich in various phytochemical compounds. These phytochemical compounds have pharmacological roles in treating various diseases conditions; apart from being widely available in nature and commercially beneficial. The phytochemical compounds in plants are constantly being explored through various experimental studies to determine the molecular basis of how medicinal plants work in relation to drugs and diseases and to develop neutraceuticals for improving conditions. This review summarizes 110 medicinal plants and their phytochemical constituents that have been shown to possess anti-depressant activity. This review also highlights the various mechanisms of anti-depressant action of some of these plants and their plant parts like roots, stem, leaves, flowers, fruit or whole plant; phytochemical compounds showing anti-depressant activity such flavanoids, steroids, saponins, sugars, lectins, alkaloids, etc.; and various anti-depressant screening models used such as tail suspension test, forced swim test, chronic unpredictable stress test, sucrose preference test, monoamine oxidase inhibition assay, learned helplessness test, open field test, hole board test, etc. However, mechanistic evaluation of many of these plants still needs to be investigated and explored.

Pharmacological Characterization of H05, a Novel Serotonin and Noradrenaline Reuptake Inhibitor with Moderate 5-HT2A Antagonist Activity for the Treatment of Depression

Multitarget antidepressants selectively inhibiting monoaminergic transporters and 5-hydroxytryptamine (5-HT) 2A receptor have demonstrated higher efficacy and fewer side effects than selective serotonin reuptake inhibitors. In the present study, we synthesized a series of novel 3-(benzo[d][1,3]dioxol-4-yloxy)-3-arylpropyl amine derivatives, among which compound H05 was identified as a lead, exhibiting potent inhibitory effects on both serotonin (K_i = 4.81 nM) and norepinephrine (NE) (K_i = 6.72 nM) transporters and moderate 5-HT_2A antagonist activity (IC₅₀ = 60.37 nM). H05 was able to dose-dependently reduce the immobility duration in mouse forced swimming test and tail suspension test, with the minimal effective doses lower than those of duloxetine, and showed no stimulatory effect on locomotor activity. The administration of H05 (5, 10, and 20 mg/kg, by mouth) significantly shortened the immobility time of adrenocorticotropin-treated rats that serve as a model of treatment-resistant depression, whereas imipramine (30 mg/kg, by mouth) and duloxetine (30 mg/kg, by mouth) showed no obvious effects. Chronic treatment with H05 reversed the depressive-like behaviors in a rat model of chronic unpredictable mild stress and a mouse model of corticosterone-induced depression. Microdialysis analysis revealed that the administration of H05 at either 10 or 20 mg/kg increased the release of 5-HT and NE from the frontal cortex. The pharmacokinetic (PK) and brain penetration analyses suggest that H05 has favorable PK properties with good blood-brain penetration ability. Therefore, it can be concluded that H05, a novel serotonin and NE reuptake inhibitor with 5-HT_2A antagonist activity, possesses efficacious activity in the preclinical models of depression and treatment-resistant depression, and it may warrant further evaluation for clinical development.

Psilocybin with psychological support for treatment-resistant depression: six-month follow-up

RATIONALE

Recent clinical trials are reporting marked improvements in mental health outcomes with psychedelic drug-assisted psychotherapy.

OBJECTIVES

Here, we report on safety and efficacy outcomes for up to 6 months in an open-label trial of psilocybin for treatment-resistant depression.

METHODS

Twenty patients (six females) with (mostly) severe, unipolar, treatment-resistant major depression received two oral doses of psilocybin (10 and 25 mg, 7 days apart) in a supportive setting. Depressive symptoms were assessed from 1 week to 6 months post-treatment, with the self-rated QIDS-SR16 as the primary outcome measure.

RESULTS

Treatment was generally well tolerated. Relative to baseline, marked reductions in depressive symptoms were observed for the first 5 weeks post-treatment (Cohen's d = 2.2 at week 1 and 2.3 at week 5, both p < 0.001); nine and four patients met the criteria for response and remission at week 5. Results remained positive at 3 and 6 months (Cohen's d = 1.5 and 1.4, respectively, both p < 0.001). No patients sought conventional antidepressant treatment within 5 weeks of psilocybin. Reductions in depressive symptoms at 5 weeks were predicted by the quality of the acute psychedelic experience.

CONCLUSIONS

Although limited conclusions can be drawn about treatment efficacy from open-label trials, tolerability was good, effect sizes large and symptom improvements appeared rapidly after just two psilocybin treatment sessions and remained significant 6 months post-treatment in a treatment-resistant cohort. Psilocybin represents a promising paradigm for unresponsive depression that warrants further research in double-blind randomised control trials.

The Risk of Hip Fracture Due to Mirtazapine Exposure When Switching Antidepressants or Using Other Antidepressants as Add-On Therapy

Background

Antidepressants are associated with adverse effects such as sedation and hypotension, which can result in falls and fractures. Few studies have assessed the risk of hip fracture due to mirtazapine, and no known studies have assessed whether the risk of hip fracture is higher in patients taking other antidepressant medicines in combination with mirtazapine.

Objectives

This study aimed to examine the risk of hip fracture in older people due to mirtazapine use as well as switching between or concurrently using mirtazapine and other antidepressants.

Method

A matched case–control study was conducted. Cases were people aged over 65 years who were eligible for Australian Government Department of Veterans’ Affairs (DVA) benefits and who sustained a hip fracture between 2009 and 2012. Each case was matched with up to four randomly selected controls of the same gender and age (± 2 years). Multivariable conditional logistic regression was used to estimate associations between antidepressant use and hip fracture. In order to assess whether combined antidepressant effects differed from the sum of individual effects, the relative excess risk due to interaction (RERI) was calculated.

Results

The study population comprised 8828 cases and 35,310 controls. The median age of these participants was 88 years and 63% were women. The risk of hip fracture was increased for mirtazapine (continuous use: odds ratio [OR] 1.27, 95% confidence interval [CI] 1.12–1.44). The combinations associated with increased odds of hip fracture were addition of selective serotonin reuptake inhibitors (SSRIs) to mirtazapine (OR 11, 95% CI 2.2–51; RERI 7.7, 95% CI −9.0 to 24), addition of tricyclic antidepressants (TCAs) to mirtazapine (OR 14, 95% CI 1.4–132; RERI 12, 95% CI −19 to 43) and continuous use of both SSRIs and mirtazapine (OR 2.4, 95% CI 1.4–4.2; RERI 0.4, 95% CI −0.9 to 1.7). RERIs indicated that the effect of each antidepressant pair equalled the sum of the effects of individual antidepressant use. There was no evidence of dispensing of lower strength mirtazapine upon introducing TCAs and SSRIs.

Conclusions

Our results show elevated risk of hip fracture following use of mirtazapine alone and in combination with other antidepressants. The overlapping use of antidepressants may reflect the treatment of comorbidities (e.g. anxiety), switching from mirtazapine to other antidepressants, or add-on therapy. Our results highlight the risks of employing add-on therapy or switching antidepressants in older people, providing further evidence to support cautious cross-tapering where switching between antidepressants is required.

Electronic supplementary material

The online version of this article (doi:10.1007/s40801-017-0120-y) contains supplementary material, which is available to authorized users.

Serotonin and brain function: a tale of two receptors

Previous attempts to identify a unified theory of brain serotonin function have largely failed to achieve consensus. In this present synthesis, we integrate previous perspectives with new and older data to create a novel bipartite model centred on the view that serotonin neurotransmission enhances two distinct adaptive responses to adversity, mediated in large part by its two most prevalent and researched brain receptors: the 5-HT1A and 5-HT2A receptors. We propose that passive coping (i.e. tolerating a source of stress) is mediated by postsynaptic 5-HT1AR signalling and characterised by stress moderation. Conversely, we argue that active coping (i.e. actively addressing a source of stress) is mediated by 5-HT2AR signalling and characterised by enhanced plasticity (defined as capacity for change). We propose that 5-HT1AR-mediated stress moderation may be the brain's default response to adversity but that an improved ability to change one's situation and/or relationship to it via 5-HT2AR-mediated plasticity may also be important - and increasingly so as the level of adversity reaches a critical point. We propose that the 5-HT1AR pathway is enhanced by conventional 5-HT reuptake blocking antidepressants such as the selective serotonin reuptake inhibitors (SSRIs), whereas the 5-HT2AR pathway is enhanced by 5-HT2AR-agonist psychedelics. This bipartite model purports to explain how different drugs (SSRIs and psychedelics) that modulate the serotonergic system in different ways, can achieve complementary adaptive and potentially therapeutic outcomes.

Duloxetine-mirtazapine combination in depressive illness: The case for Limerick 'rocket fuel'

The use of complex psychopharmacological regimens is increasingly advocated in more difficult to treat depressive illness. The combination of venlafaxine with mirtazapine - 'California rocket fuel' is one such example involving an SNRI combined with a NaSSA. We describe two cases that highlight the potential usefulness of duloxetine used in combination with mirtazapine that also emphasise the danger of drug-induced hypomanic switching. This combination may have a specific role for carefully selected patients but caution is needed given the potential to induce profound alterations in mental state.

Combination pharmacotherapy in unipolar depression

It is estimated that between 60 and 80% of those with major depressive disorder do not achieve full symptomatic remission from first-line antidepressant monotherapy. Residual depressive symptoms substantially impair quality of life and add to the risk of recurrence. It is now clear that depression would benefit from more vigorous treatment, in order to ameliorate its disease burden. While there are established algorithms in situations of treatment resistance, the use of combination pharmacotherapy in unipolar depression is a relatively under-investigated area of treatment and may be an effective and tolerable strategy that maximizes the available resources. This paper reviews the current evidence for combination pharmacotherapy in unipolar depression and discusses its clinical applications.

World Federation of Societies of Biological Psychiatry (WFSBP) guidelines for biological treatment of unipolar depressive disorders, part 1: update 2013 on the acute and continuation treatment of unipolar depressive disorders

OBJECTIVES

This 2013 update of the practice guidelines for the biological treatment of unipolar depressive disorders was developed by an international Task Force of the World Federation of Societies of Biological Psychiatry (WFSBP). The goal has been to systematically review all available evidence pertaining to the treatment of unipolar depressive disorders, and to produce a series of practice recommendations that are clinically and scientifically meaningful based on the available evidence. The guidelines are intended for use by all physicians seeing and treating patients with these conditions.

METHODS

The 2013 update was conducted by a systematic update literature search and appraisal. All recommendations were approved by the Guidelines Task Force.

RESULTS

This first part of the guidelines (Part 1) covers disease definition, classification, epidemiology, and course of unipolar depressive disorders, as well as the management of the acute and continuation phase treatment. It is primarily concerned with the biological treatment (including antidepressants, other psychopharmacological medications, electroconvulsive therapy, light therapy, adjunctive and novel therapeutic strategies) of adults.

CONCLUSIONS

To date, there is a variety of evidence-based antidepressant treatment options available. Nevertheless there is still a substantial proportion of patients not achieving full remission. In addition, somatic and psychiatric comorbidities and other special circumstances need to be more thoroughly investigated. Therefore, further high-quality informative randomized controlled trials are urgently needed.

Tianeptine combination for partial or non-response to selective serotonin re-uptake inhibitor monotherapy

AIMS

The goal of this study was to assess the efficacy and tolerability of tianeptine in combination with selective serotonin re-uptake inhibitor (SSRI) in partial responders or non-responders to SSRI monotherapy.

METHODS

In this prospective, open-label, 6-week study, 150 patients with major depressive disorder who had previously not responded or partially responded to SSRI monotherapy were recruited. Tianeptine was given in combination with an SSRI for 6 weeks.

RESULTS

Significant improvements were observed in the mean scores of the Hamilton Depression Rating Scale (HDRS), Montgomery-Åsberg Depression Rating Scale (MADRS), and Clinical Global Impression-Severity (CGI-S). The change in the mean HDRS, MADRS, and CGI-S scores was significant from week 1. The response rates were 64.7% (HDRS) and 68.7% (MADRS), and the remission rates were 34.0% (HDRS) and 42.0% (MADRS) at week 6. Thirty-six patients (24.0%) reported adverse events that were determined by the investigator to be related to one of the study drugs. The tianeptine and SSRI combination was generally well-tolerated.

CONCLUSIONS

A combination strategy with tianeptine may be an effective and well-tolerated tool for patients who have failed to adequately respond to SSRI monotherapy.

Efficacy and safety of add on low-dose mirtazapine in depression

Objectives:

Although antidepressant medications are effective, they have a delayed onset of effect. Mirtazapine, an atypical antidepressant is an important option for add-on therapy in major depression. There is insufficient data on mirtazapine in Indian population; hence this study was designed to study the add-on effect of low-dose mirtazapine with selective serotonin reuptake inhibitors (SSRIs) in major depressive disorder (MDD) in Indian population.

Materials and Methods:

In an open, randomized study, 60 patients were divided into two groups. In Group A (n=30) patients received conventional SSRIs for 6 weeks. In Group B (n=30) patients received conventional SSRIs with low-dose mirtazapine for 6 weeks. Patients were evaluated at baseline and then at 1, 2, 3, 4, 5, and 6 weeks.

Results:

There was significant improvement in Hamilton Depression Rating Scale (HDRS), Montgomery and Asberg depression rating scale (MADRS) scores (P<0.05) in both groups. Mirtazapine in low dose as add on therapy showed improvement in scores, had earlier onset of action, and more number of responders and remitters as compared to conventional treatment (P<0.05). No serious adverse event was reported in either of the groups.

Conclusion:

Low-dose mirtazapine as add-on therapy has shown better efficacy, earlier onset of action and more number of responders and remitters as compared to conventional treatment in MDD in Indian patients.

The first 100 patients in the SUN(^_^)D trial (strategic use of new generation antidepressants for depression): examination of feasibility and adherence during the pilot phase

BACKGROUND

Initial glitches and unexpected inconsistencies are unavoidable in the early stage of a large, multi-centre trial. Adaptive modifications of the trial's protocol and operational procedures to ensure its smooth running are therefore imperative. We started a large pragmatic, multi-centre, assessor-blinded, 25-week trial to investigate the optimal first- and second-line treatments for untreated episodes of nonpsychotic major depression in 2010 [Strategic Use of New generation antidepressants for Depression, abbreviated SUN(^_^)D] and would like to herein report an examination of the trial's feasibility and adherence among the first 100 participants.

METHODS

We examined the participants' characteristics, the treatments that were allocated and received during each step of the trial, and the quality of the outcome assessments among the first 100 patients enrolled in the SUN(^_^)D trial.

RESULTS

Of the 2,743 first-visit patients who visited the two collaborating centres between December 2010 and July 2011, 382 were judged as potentially eligible, and 100 of these patients provided written informed consent. These patients represented the whole spectrum of mild to very severe depression. Of the 93 patients who had reached Week 3 of the study by the end of July 2011, one withdrew consent for both the treatment and the assessment, and eight withdrew consent for the treatment only. Altogether, the primary outcomes were successfully assessed in 90 (96.8%) of the patients at Week 3. Of the 72 patients who had reached Week 9, three withdrew consent for the treatment, but 70 were successfully interviewed (97.2%). Of the 32 patients who had reached Week 25, 29 (90.5%) were successfully followed up. The inter-rater reliability of the assessments of the primary outcomes was nearly perfect and their successful blinding was confirmed. Minor modifications and clarifications to the protocol were deemed necessary.

DISCUSSION

Given the satisfactory feasibility and adherence to the study protocol and the minor modifications that were necessary, we conclude that the data obtained from the first 100 patients can be safely included in the main study. We now intend to accelerate the study by recruiting more collaborating centres and clinics/hospitals.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT01109693.

An extension of hypotheses regarding rapid-acting, treatment-refractory, and conventional antidepressant activity of dextromethorphan and dextrorphan

It was previously hypothesized that dextromethorphan (DM) and dextrorphan (DX) may possess antidepressant properties, including rapid and conventional onsets of action and utility in treatment-refractory depression, based on pharmacodynamic similarities to ketamine. These similarities included sigma-1 (σ(1)) agonist and NMDA antagonist properties, calcium channel blockade, muscarinic binding, serotonin transporter (5HTT) inhibition, and μ receptor potentiation. Here, six specific hypotheses are developed in light of additional mechanisms and evidence. Comparable potencies to ketamine for DM and DX are detailed for σ(1) (DX>DM>ketamine), NMDA PCP site (DX>ketamine>DM), and muscarinic (DX>ketamine>>>>DM) receptors, 5HTT (DM>DX≫ketamine), and NMDA antagonist potentiation of μ receptor stimulation (DM>ketamine). Rapid acting antidepressant properties of DM include NMDA high-affinity site, NMDR-2A, and functional NMDR-2B receptor antagonism, σ(1) stimulation, putative mTOR activation (by σ(1) stimulation, μ potentiation, and 5HTT inhibition), putative AMPA receptor trafficking (by mTOR activation, PCP antagonism, σ(1) stimulation, μ potentiation, and 5HTT inhibition), and dendritogenesis, spinogenesis, synaptogenesis, and neuronal survival by NMDA antagonism and σ(1) and mTOR signaling. Those for dextrorphan include NMDA high-affinity site and NMDR-2A antagonism, σ(1) stimulation, putative mTOR activation (by σ(1) stimulation and ß adrenoreceptor stimulation), putative AMPA receptor trafficking (by mTOR activation, PCP antagonism, σ(1) stimulation, ß stimulation, and μ antagonism), and dendritogenesis, spinogenesis, synaptogenesis, and neuronal survival by NMDA antagonism and σ(1) and mTOR signaling. Conventional antidepressant properties for dextromethorphan and dextrorphan include 5HTT and norepinephrine transporter inhibition, σ(1) stimulation, NMDA and PCP antagonism, and possible serotonin 5HT1b/d receptor stimulation. Additional properties for dextromethorphan include possible presynaptic α(2) adrenoreceptor antagonism or postsynaptic α(2) stimulation and, for dextrorphan, ß stimulation and possible muscarinic and μ antagonism. Treatment-refractory depression properties include increased serotonin and norepinephrine availability, PCP, NMDR-2B, presynaptic alpha-2 antagonism, and the multiplicity of other antidepressant receptor mechanisms. Suggestions for clinical trials are provided for oral high-dose dextromethorphan and Nuedexta (dextromethorphan combined with quinidine to block metabolism to dextrorphan, thereby increasing dextromethorphan plasma concentrations). Suggestions include exclusionary criteria, oral dosing, observation periods, dose-response approaches, and safety and tolerability are considered. Although oral dextromethorphan may be somewhat more likely to show efficacy through complementary antidepressant mechanisms of dextrorphan, a clinical trial will be more logistically complex than one of Nuedexta due to high doses and plasma level variability. Clinical trials may increase our therapeutic armamentarium and our pharmacological understanding of treatment-refractory depression and antidepressant onset of action.

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.

The association between conventional antidepressants and the metabolic syndrome: a review of the evidence and clinical implications

Major depressive disorder is a prevalent recurrent medical syndrome associated with inter-episodic dysfunction. The metabolic syndrome is comprised of several established risk factors for cardiovascular disease (i.e. abdominal obesity, dyslipidaemia, dysglycaemia and hypertension). The criterion items of the metabolic syndrome collectively represent a multi-dimensional risk factor for cardiovascular disease and type 2 diabetes mellitus. Extant evidence indicates that both major depressive disorder and the metabolic syndrome, albeit distinct, often co-occur and are possibly subserved by overlapping pathophysiology and causative mechanisms. Conventional antidepressants exert variable effects on constituent elements of the metabolic syndrome, inviting the need for careful consideration prior to treatment selection and sequencing. Initiating and maintaining antidepressant therapy should include routine surveillance for clinical and/or biochemical evidence suggestive of the metabolic syndrome.

Effects of adjunctive reboxetine in patients with duloxetine-resistant depression: a 12-week prospective study

The efficacy of the combination therapy with two antidepressants from different pharmacological families in patients with treatment-resistant depression has been reported in multiple studies. In this prospective 12-weeks open-label study, we assessed the effectiveness of the addition of reboxetine to 79 depressive outpatients diagnosed with major depressive disorder (MDD) according to the DSM-IV criteria who had previously not responded, or had done so only in a partial way, over 8 weeks of conventional treatment, in monotherapy, with duloxetine. Efficacy was assessed using the 21-item Hamilton Depression Rating Scale (HDRS) and the Clinical Global Impression-Improvement (CGI-I). Safety was evaluated by recording spontaneously reported adverse events. Data were analysed on an intent-to-treat basis, using the last-observation-carried-forward method. Mean HDRS reduction was 65.5% (P < 0.0001). The percentages of responders (>or=50% reduction in HDRS) and patients considered benefiting from complete remission (HDRS <or= 10 points) at week 12 were 76% and 69.3%, respectively. By the end of the treatment, the score of CGI-I decreased 68.5% (P < 0.0001). Percentage of patient improving (CGI < 4 points) was 95.8%. The most common non-serious adverse events were dry mouth, increased sweating, constipation and difficulty passing urine. The results of this study suggest that the combination strategy with reboxetine may be an effective and well-tolerated tool in duloxetine-resistant patients.

‘It takes some time to get into the rhythm - and to slow the flow of thought’: A qualitative study about experience of time and narrative in psychological interventions in general practice

General practitioners (GPs) treat more than 90 per cent of patients with mental disease. Time restriction is often seen as a hindrance to their engagement in psychological treatment. This study aimed to explore GPs’ experiences of time when delivering ‘talking therapy’ and to analyse how time influenced the treatment of emotional problems in routine consultations. A qualitative approach was chosen, the data consisted of interviews with 14 GPs and observation of consecutive consultations in four of the participants’ practices. Analysis was made by Interpretative Phenomenological Analysis. Eleven participants delivered talking therapy, five (therapeutically minded participants) often. Three aspects of time emerged: (1) the chronological time of the schedule; (2) the inner time with another rhythm and flow of thought; (3) the longitudinal time where meeting repeatedly for short consultations promoted a trusting relationship where problems were disclosed gradually and a narrative was created. With therapeutic participants the same aspects of time could be identified in routine consultations. Stress and a heavy workload counteracted the perception of inner time. Theories of time and narrative from psychotherapeutic thinking could be applied, form links to the unconscious and the narrative time and could possibly be made more explicit in general practice. Awareness of the different time aspects is necessary for improving the treatment of mental health in primary care. Political and organizational willingness to secure the necessary working conditions is, however, equally important for optimal treatment.

In the clinic. Depression

This issue provides a clinical overview of depression focusing on prevention, diagnosis, treatment, practice improvement, and patient information. Readers can complete the accompanying CME quiz for 1.5 credits. Only ACP members and individual subscribers can access the electronic features of In the Clinic. Non-subscribers who wish to access this issue of In the Clinic can elect "Pay for View." Subscribers can receive 1.5 category 1 CME credits by completing the CME quiz that accompanies this issue of In the Clinic. The content of In the Clinic is drawn from the clinical information and education resources of the American College of Physicians (ACP), including PIER (Physicians' Information and Education Resource) and MKSAP (Medical Knowledge and Self Assessment Program). Annals of Internal Medicine editors develop In the Clinic from these primary sources in collaboration with the ACP's Medical Education and Publishing division and with assistance of science writers and physician writers. Editorial consultants from PIER and MKSAP provide expert review of the content. Readers who are interested in these primary resources for more detail can consult www.acponline.org, http://pier.acponline.org, and other resources referenced within each issue of In the Clinic.

Pharmacologic approaches to treatment resistant depression: a re-examination for the modern era

IMPORTANCE OF THE FIELD

Treatment-resistant depression (TRD) is common and debilitating. Initial treatment is often insufficient to achieve full remission in a given depressive episode, resulting in more frequent episodes, worsened severity, and major disability.

AREAS COVERED IN THIS REVIEW

This review surveys literature on the diagnosis and pharmacological management of TRD in light of recent developments. Evidence regarding commonly used treatment options is critically examined and key recommendations are offered. The review ends by considering drugs acting on the melatonin, acetylcholine, and glutamate systems that hold promise as future options for TRD.

WHAT THE READER WILL GAIN

Recent trends and research findings have impacted how the evidence supporting different approaches to TRD should be evaluated. For example, many earlier TRD studies employed tricyclics as the primary antidepressant, but tricyclics have now been superseded by selective serotonin reuptake inhibitors (SSRIs) in routine clinical practice. This deficiency has been addressed by the Sequenced Treatment Alternatives to Relieve Depression (STAR*D) study, the largest effectiveness study of TRD ever conducted. However, design characteristics of the STAR*D study preclude simple comparisons with earlier studies.

TAKE HOME MESSAGE

A shortcoming of most treatment recommendations for TRD is their reliance on older studies that do not reflect the current preeminence of SSRIs in clinical practice. This has distorted the prioritization of pharmacological strategies for TRD. Efforts to correct this distortion with effectiveness research, designed to better reflect current practice trends, require critical consideration of the strengths and limitations of this approach.

Therapeutic options for treatment-resistant depression

Treatment-resistant depression (TRD) presents major challenges for both patients and clinicians. There is no universally accepted definition of TRD, but results from the US National Institute of Mental Health's (NIMH) STAR*D (Sequenced Treatment Alternatives to Relieve Depression) programme indicate that after the failure of two treatment trials, the chances of remission decrease significantly. Several pharmacological and nonpharmacological treatments for TRD may be considered when optimized (adequate dose and duration) therapy has not produced a successful outcome and a patient is classified as resistant to treatment. Nonpharmacological strategies include psychotherapy (often in conjunction with pharmacotherapy), electroconvulsive therapy and vagus nerve stimulation. The US FDA recently approved vagus nerve stimulation as adjunctive therapy (after four prior treatment failures); however, its benefits are seen only after prolonged (up to 1 year) use. Other nonpharmacological options, such as repetitive transcranial stimulation, deep brain stimulation or psychosurgery, remain experimental and are not widely available. Pharmacological treatments of TRD can be grouped in two main categories: 'switching' or 'combining'. In the first, treatment is switched within and between classes of compounds. The benefits of switching include avoidance of polypharmacy, a narrower range of treatment-emergent adverse events and lower costs. An inherent disadvantage of any switching strategy is that partial treatment responses resulting from the initial treatment might be lost by its discontinuation in favour of another medication trial. Monotherapy switches have also been shown to have limited effectiveness in achieving remission. The advantage of combination strategies is the potential to build upon achieved improvements; they are generally recommended if partial response was achieved with the current treatment trial. Various non-antidepressant augmenting agents, such as lithium and thyroid hormones, are well studied, although not commonly used. There is also evidence of efficacy and increasing use of atypical antipsychotics in combination with antidepressants, for example, olanzapine in combination with fluoxetine (OFC) or augmentation with aripiprazole. The disadvantages of a combination strategy include multiple medications, a broader range of treatment-emergent adverse events and higher costs. Several experimental pharmaceutical treatment alternatives for TRD are also being explored in combination with antidepressants or as monotherapy. These less studied alternative compounds include pindolol, inositol, CNS stimulants, hormones, herbal supplements, omega-3 fatty acids, S-adenosyl-L-methionine, folic acid, lamotrigine, modafinil, riluzole and topiramate. In summary, despite an increasing variety of choices for the treatment of TRD, this condition remains universally undefined and represents an area of unmet medical need. There are few known approved pharmacological agents for TRD (aripiprazole and OFC) and overall outcomes remain poor. This might be an indication that depression itself is a heterogeneous condition with a great diversity of pathologies, highlighting the need for careful evaluation of individuals with depressive symptoms who are unresponsive to treatment. Clearly, more research is needed to provide clinicians with better guidance in making those treatment decisions--especially in light of accumulating evidence that the longer patients are unsuccessfully treated, the worse their long-term prognosis tends to be.

Combined treatment with reboxetine in depressed patients with no response to venlafaxine: a 6-week follow-up study

OBJECTIVE

The purpose of present study was to evaluate the efficacy of the addition of reboxetine in patients that had not previously responded, or had done so only partially, over 6 weeks of conventional pharmacological treatment with venlafaxine.

METHODS

This open-label, prospective and multicentric study included 40 outpatients diagnosed with major depressive disorder according to the DSM-IV criteria. Efficacy was assessed using the 21-item Hamilton Depression Rating Scale (HAMD) and the Clinical Global Impression-Improvement (CGI-I). Safety was evaluated by recording spontaneously reported adverse events. Data were analysed on an intent-to-treat basis, using the last-observation-carried-forward method.

RESULTS

Mean HAMD reduction was 34.9% (P < 0.0001). The percentages of responders (≥50% reduction in HAMD) and patients considered as benefiting from complete remission (HAMD ≤ 10 points) at week 6 were 27.5 and 12.5%, respectively. By the end of the treatment, the score of CGI-I decreased 24.8% (P < 0.0001). Percentage of patient improving (CGI < 4 points) was 47.5%. The most common non-serious adverse events were constipation, nervousness, anxiety and insomnia.

CONCLUSION

These findings suggest that the combined treatment of reboxetine and venlafaxine, in venlafaxine-resistant patients, may be an effective and well-tolerated strategy.

Combined treatments for major depression

Major depression is a chronic disorder with a high morbidity and mortality. Approved treatment for major depression at present includes monotherapy with antidepressants of different pharmacologic classes. There is increasingly widespread use of two other options: augmentation, the addition to an antidepressant of a second compound that is not an antidepressant when used alone; and combination, which is the use of two antidepressants concurrently to enhance or accelerate response. This review focuses on the data available to support these various augmentation and combination treatments.

Creating more effective antidepressants: clues from the clinic

Antidepressant medications have eased the suffering of millions of people. In addition to treating depression, antidepressant drugs also treat several anxiety disorders. Unfortunately, there are problematic limitations with antidepressant agents, including a delayed therapeutic response and insufficient efficacy. Emerging evidence shows that atypical antipsychotic agents can be used as augmentation therapy in patients with poor responses to antidepressants. Future drugs combining key features of antidepressant and atypical antipsychotic agents could offer new promise for patients suffering from obsessive-compulsive disorder, post-traumatic stress disorder, panic disorder, generalized anxiety disorder and depression.

Safety and efficacy of s-citalopram in patients with co-morbid major depression and diabetes mellitus

OBJECTIVE

The presence of co-morbid depressive symptoms may have a negative impact on the management of diabetes mellitus. Moreover, some antidepressants may adversely affect glycemic control. Selective serotonin reuptake inhibitors (SSRIs) may improve glycemic control and may be beneficial for patients with co-morbid depression and diabetes. We examined the safety and efficacy of s-citalopram therapy in patients with co-morbid depression and diabetes, and its ability to improve glycemic control.

RESEARCH DESIGN AND METHODS

17 patients were enrolled into the trial and 14 patients received open-label s-citalopram therapy for up to 16 weeks. Clinical outcome measures included the 17-item Hamilton depression rating (HAM-D 17) and the clinical global impressions severity (CGI/S) and change (CGI/C) ratings. In addition, fasting glucose, fructosamine, and glycosylated hemoglobin-A(1C) measures were obtained before and during s-citalopram therapy.

RESULTS

We observed a significant reduction in mean HAM-D 17 (p<0.001), CGI/S (p=0.001) and CGI/C (p=0.001) ratings during s-citalopram therapy. We also observed a modest, non-significant reduction in fasting glucose, fructosamine, and glycosylated hemoglobin-A(1C) levels during s-citalopram therapy.

LIMITATION

Limitations of this study include a modest patient sample size and a 16-week treatment duration which may have been insufficient to demonstrate the full effect of SSRI therapy on glycemic control.

CONCLUSION

We observed a significant reduction in depressive symptoms and modest, non-significant reductions in fasting glucose, fructosamine, and glycosylated hemoglobin-A(1C) levels during SSRI therapy of co-morbid depression and diabetes.

Venlafaxine-mirtazapine combination in the treatment of persistent depressive illness

The combination of mirtazapine and venlafaxine has been suggested as a treatment option for difficult to treat depressive illness. We describe 32 patients with persistent depressive illness (44% male; mean age 42 years; mean 2.5 previous antidepressant trials) that received mirtazapine and venlafaxine in combination at some point over the 3 year period between 2002 and 2005. Clinical response rates (CGI-improvement score of two or less) were 44% at 4 weeks and 50% at 8 weeks. At 6 month review, 18 patients (56% of the original cohort and 75% of those still receiving treatment) had significantly responded. Clinical response typically occurred at moderate and high dose treatment with both agents. A total of 44% experienced some adverse effects with sedation (19%) and weight gain (19%) most frequent. Five patients discontinued treatment due to these effects. No serious adverse effects were linked to the combination treatment. We discuss the implications of these findings for the use of venlafaxine and mirtazapine in combination in more difficult to treat patients with depression.

Current status of augmentation and combination treatments for major depressive disorder: a literature review and a proposal for a novel approach to improve practice

Most patients with major depressive disorder (MDD) do not reach symptom remission. These patients with residual symptoms have worse function and worse prognosis than those who remit. Several augmentation and combination treatments are used to either increase the chances of achieving remission or to eliminate/minimize residual depressive symptoms. Evidence for these pharmacological approaches rests primarily on open, uncontrolled studies, and there are clearly not enough controlled studies. Clinicians should carefully weigh these different treatment options to increase their patients' chances of achieving and sustaining remission from depression. This paper will review the pertinent studies and will propose a novel approach to improve practice involving the use of augmentation or combination strategies at the outset of initial treatment to primarily enhance the chances of remission through synergy and/or a broader spectrum of action. This novel approach could potentially enhance retention and/or increase remission rates since the lack of response with antidepressant monotherapy may lead many depressed patients with little or no benefit to drop out of treatment, precluding the subsequent use of augmentation or combination strategies altogether. In addition, the emergence of certain side-effects (e.g., agitation, insomnia) or the persistence of some initial baseline symptoms (e.g., anxiety, insomnia) may lead to premature discontinuation from monotherapy in the absence of concomitant use of augmenting pharmacological options targeting these symptoms.

Reboxetine addition in patients with mirtazapine-resistant depression: a case series

OBJECTIVES

Treatment-resistant depression is a common occurrence in clinical practice as well as combination treatment with 2 different antidepressants. In the present case series, we study the effectiveness of the addition of reboxetine, during 12 weeks, to 14 outpatients diagnosed with major depressive disorder, according to Diagnostic and Statistical Manual of Mental Disorders (Fourth Edition, Text Revision) criteria, who had previously failed to respond or who had only responded partially, over a period of 6 weeks, to conventional treatment with mirtazapine.

METHODS

Evaluation of antidepressant efficacy was carried out through the application of the 21-item Hamilton Depression Rating Scale (HDRS) and the Clinical Global Impressions-Global Improvement Scale (CGI-I).

RESULTS

The percentages of responders (HDRS>or=50%), patients in remission (HDRS<or=10), and improving (CGI-I absolute value<4) were 35.7%, 28.6%, and 64.3%, respectively. No serious side effects were observed during combination therapy, being more frequent dry mouth (2 cases).

CONCLUSIONS

The initial findings of our study show that reboxetine and mirtazapine may constitute an effective and low side effects combination.

Combined antidepressants: clinical experience

OBJECTIVE

To review the current literature on the use of combinations of antidepressive agents.

METHOD

Literature searches were undertaken and reviewed on the use of combinations of antidepressants.

RESULTS

Data sources included surveys, analyses of prescription records, decision algorithms, clinical reports, and studies comparing the monotherapy with combination therapy. More recent surveys recommend combining different selective serotonin reuptake inhibitors (SSRIs), an SSRI plus bupropion or dual action antidepressants plus an SSRI. Decision algorithms recommend an SSRI plus tricyclic antidepressant (TCA) and more recently bupropion plus venlafaxine or mirtazapine. Few controlled clinical trials comparing the combined therapy with monotherapy have been conducted. Beneficial effects have been reported with combinations of TCAs plus mianserin or SSRIs plus mirtazapine.

CONCLUSION

Adding or combining antidepressant medications has advantages for the speed of onset and maintaining the existing response. More rigorous clinical trials comparing combination therapy with monotherapy and for the development of rational treatment guidelines are required.

Cognitive training in Alzheimer's disease: a meta-analysis of the literature

OBJECTIVE

To systematically review the literature and summarize the effect of cognitive training (CT) for Alzheimer's disease (AD) patients on multiple functional domains.

METHOD

Effect sizes (Cohen's d) were calculated for 17 controlled studies identified through a comprehensive literature review.

RESULTS

An overall effect size of 0.47 was observed for all CT strategies across all measured outcomes. Mean effect sizes were higher for restorative (0.54) than for compensatory (0.36) strategies. Domain-specific effect sizes ranged from 2.16 (verbal and visual learning) to -0.38 (visuospatial functioning). Data are also presented on the relative impact of restorative and compensatory strategies for each domain of functioning.

CONCLUSION

CT evidenced promise in the treatment of AD, with primarily medium effect sizes for learning, memory, executive functioning, activities of daily living, general cognitive problems, depression, and self-rated general functioning. Restorative strategies demonstrated the greatest overall effect on functioning. Several limitations of the published literature are discussed.

Multi-target strategies for the improved treatment of depressive states: Conceptual foundations and neuronal substrates, drug discovery and therapeutic application

Major depression is a debilitating and recurrent disorder with a substantial lifetime risk and a high social cost. Depressed patients generally display co-morbid symptoms, and depression frequently accompanies other serious disorders. Currently available drugs display limited efficacy and a pronounced delay to onset of action, and all provoke distressing side effects. Cloning of the human genome has fuelled expectations that symptomatic treatment may soon become more rapid and effective, and that depressive states may ultimately be "prevented" or "cured". In pursuing these objectives, in particular for genome-derived, non-monoaminergic targets, "specificity" of drug actions is often emphasized. That is, priority is afforded to agents that interact exclusively with a single site hypothesized as critically involved in the pathogenesis and/or control of depression. Certain highly selective drugs may prove effective, and they remain indispensable in the experimental (and clinical) evaluation of the significance of novel mechanisms. However, by analogy to other multifactorial disorders, "multi-target" agents may be better adapted to the improved treatment of depressive states. Support for this contention is garnered from a broad palette of observations, ranging from mechanisms of action of adjunctive drug combinations and electroconvulsive therapy to "network theory" analysis of the etiology and management of depressive states. The review also outlines opportunities to be exploited, and challenges to be addressed, in the discovery and characterization of drugs recognizing multiple targets. Finally, a diversity of multi-target strategies is proposed for the more efficacious and rapid control of core and co-morbid symptoms of depression, together with improved tolerance relative to currently available agents.

Serotonin 5-HT2C receptors as a target for the treatment of depressive and anxious states: focus on novel therapeutic strategies

Serotonin (5-HT)2C receptors play an important role in the modulation of monoaminergic transmission, mood, motor behaviour, appetite and endocrine secretion, and alterations in their functional status have been detected in anxiodepressive states. Further, 5-HT2C sites are involved in the actions of several classes of antidepressant. At the onset of treatment, indirect activation of 5-HT2C receptors participates in the anxiogenic effects of selective 5-HT reuptake inhibitors (SSRIs) as well as their inhibition of sleep, sexual behaviour and appetite. Conversely, progressive down-regulation of 5-HT2C receptors parallels the gradual onset of clinical efficacy of SSRIs. Other antidepressants, such as nefazodone or mirtazapine, act as direct antagonists of 5-HT2C receptors. These observations underpin interest in 5-HT2C receptor blockade as a strategy for treating depressive and anxious states. This notion is supported by findings that 5-HT2C receptor antagonists stimulate dopaminergic and adrenergic pathways, exert antidepressant and anxiolytic actions in behavioural paradigms, and favour sleep and sexual function. In addition to selective antagonists, novel strategies for exploitation of 5-HT2C receptors embrace inverse agonists, allosteric modulators, ligands of homo/heterodimers, modulators of interactions with 'postsynaptic proteins', dual melatonin agonists/5-HT2C receptor antagonists and mixed 5-HT2C/alpha2-adrenergic antagonists. Intriguingly, there is evidence that stimulation of regionally discrete populations of 5-HT2C receptors is effective in certain behavioural models of antidepressant activity, and promotes neurogenesis in the hippocampus. This article explains how these ostensibly paradoxical actions of 5-HT2C antagonists and agonists can be reconciled and discusses both established and innovative strategies for the exploitation of 5-HT2C receptors in the improved management of depressed and anxious states.

To combine or not to combine? A literature review of antidepressant combination therapy

OBJECTIVE

Treatment resistant depression is a common clinical problem and a major public health concern. The use of antidepressant combinations to overcome treatment resistance, while somewhat controversial, is a popular strategy in practice. This paper reviews published trials on combination antidepressants with a view to inform clinical practice.

METHOD

A systematic but selective review of the published literature was conducted using EMBASE, PSYCHLIT and MEDLINE with relevant search terms.

RESULTS

A number of trials suggesting efficacy of combination antidepressants were found. These are incorporated into a number of treatment guidelines for the management of treatment refractory depression. Clinicians should be cautious regarding pharmacokinetic and pharmacodynamic interactions, including the serotonin syndrome, however combination strategies are an effective option.

CONCLUSIONS

Many antidepressants can be usefully combined especially if they engage separate mechanisms of action. Clinically, antidepressant combinations provide a useful resort in otherwise treatment resistant individuals. However, much further research is needed to determine relative efficacy and determine long term outcome.

Antidepressant combinations: epidemiological considerations

OBJECTIVE

To evaluate the treatment options in patients who do not respond appropriately to a single antidepressant alone.

METHOD

The medical literature was reviewed.

RESULTS

A number of strategies are available if a patient fails to respond adequately to initial antidepressant treatment, including the combination with another psychoactive drug. Evidence published to date appears to suggest that benzodiazepines are the drugs most frequently combined with antidepressants. The combination of two antidepressants together is less common, occurring in approximately 5-15% of cases showing a poor initial response. The key figures involved in such co-prescription are psychiatrists.

CONCLUSION

There appears to be considerable variability in the data concerning combined prescription of antidepressants, with differences arising depending on the type of physician, the type of patient or illness and the geographical area. It is also unclear how closely research findings parallel with what doctors do in everyday practice.

Chronoamperometry to determine differential reductions in uptake in brain synaptosomes from serotonin transporter knockout mice

The serotonin transporter (SERT) is a neuronal plasma membrane protein whose primary function is to take up the neurotransmitter serotonin from the extracellular space, thereby controlling the spatial and temporal aspects of serotonergic signaling in the brain. In humans, a commonly expressed genetic variant of the serotonin transporter gene results in 40% reductions in SERT expression that have been linked to increases in anxiety-related personality traits and susceptibility to stress-associated depression. Mice have been engineered to express similar reductions in SERT expression to investigate transporter-mediated control of serotonin neurotransmission and behavior. We employed carbon fiber microelectrode voltammetry (chronoamperometry) to examine serotonin clearance rates in brain liposomes (synaptosomes) prepared from mice with 50% (SERT(+/)(-)) or complete (SERT(-)(/)(-)) loss of SERT expression. Initial characterization of uptake showed that transport of serotonin was enhanced in the presence of oxygen and abolished when synaptosomes were stirred. Additionally, uptake was prevented by inclusion of the serotonin-selective reuptake inhibiting drug paroxetine in the incubation medium. Most notably, unlike prior studies using established radiochemical methods in synaptosomes, we determined 60% reductions in serotonin uptake rates in SERT(+/)(-) mice in two different brain regions-striatum and frontal cortex. Serotonin uptake was not detected in either brain region in SERT(-)(/)(-) mice. Thus, electroanalytical methods offer distinct advantages stemming from excellent temporal resolution for determining transporter kinetics. Moreover, these appear necessary for delineating moderate but biologically important changes in neurotransmitter transporter function.

Discovery of a new series of centrally active tricyclic isoxazoles combining serotonin (5-HT) reuptake inhibition with alpha2-adrenoceptor blocking activity

The synthesis and pharmacology of a new series of 3-piperazinylmethyl-3a,4-dihydro-3H-[1]benzopyrano[4,3-c]isoxazoles that combine central serotonin (5-HT) reuptake inhibition with alpha(2)-adrenoceptor blocking activity is described as potential antidepressants. Four compounds were selected for further evaluation, and the combination of both activities was found to be stereoselective, residing mainly in one enantiomer. Reversal of the loss of righting induced by the alpha(2)-agonist medetomidine in rats confirmed the alpha(2)-adrenoceptor blocking activity in vivo and also demonstrated CNS penetration. Antagonism of p-chloroamphetamine (pCA)-induced excitation as well as blockade of the neuronal 5-HT depletion induced by p-CA administration in rats confirmed their ability to block the central 5-HTT, even after oral administration. Replacement of the oxygen atom at the 5-position of the tricyclic scaffold by a nitrogen or a carbon atom, as well as O-substitution at position 7, led also to active compounds, both in vitro and in vivo.

Effect of patient gender on late-life depression management

PURPOSE

To determine whether patient gender influences physicians' management of late-life major depression in older and younger elderly patients.

METHODS

In 1996-2001, physician subjects viewed a professionally produced videotape vignette portraying an elderly patient meeting diagnostic criteria for major depression, then answered interviewer-administered questions about differential diagnosis and treatment. Patient gender and other characteristics were systematically varied in different versions of the videotape, but clinical content was held constant. This was a stratified random sample of 243 internists and family physicians with Veterans Health Administration (VA) or non-VA ambulatory care practices in the Northeastern United States. Outcomes were whether physicians followed a guideline-recommended management approach: treating with antidepressants or mental health referral or both and seeing the patient for follow-up within 2 weeks.

RESULTS

Only 19% of physicians recommended treating depression (12% recommended antidepressants and 7% mental health referral), and 43% recommended follow-up within 2 weeks. Patient gender did not influence management recommendations in either younger old (67 year old) or older old (79 year old) patients (p > 0.12 for all comparisons).

CONCLUSIONS

Gender disparities previously documented in the management of major conditions are not seen for the management of depression, a potentially stigmatized condition that does not require resource-intense interventions.