Determinants of pharmacologic treatment failure in panic disorder

GABAergic circuits of the basolateral amygdala and generation of anxiety after traumatic brain injury

Traumatic brain injury (TBI) has reached epidemic proportions around the world and is a major public health concern in the United States. Approximately 2.8 million individuals sustain a traumatic brain injury and are treated in an Emergency Department yearly in the U.S., and about 50,000 of them die. Persistent symptoms develop in 10-15% of the cases including neuropsychiatric disorders. Anxiety is the second most common neuropsychiatric disorder that develops in those with persistent neuropsychiatric symptoms after TBI. Abnormalities or atrophy in the temporal lobe has been shown in the overwhelming number of TBI cases. The basolateral amygdala (BLA), a temporal lobe structure that consolidates, stores and generates fear and anxiety-based behavioral outputs, is a critical brain region in the anxiety circuitry. In this review, we sought to capture studies that characterized the relationship between human post-traumatic anxiety and structural/functional alterations in the amygdala. We compared the human findings with results obtained with a reproducible mild TBI animal model that demonstrated a direct relationship between the alterations in the BLA and an anxiety-like phenotype. From this analysis, both preliminary insights, and gaps in knowledge, have emerged which may open new directions for the development of rational and more efficacious treatments.

Aligning the many definitions of treatment resistance in anxiety disorders: A systematic review

Anxiety Disorders often show a chronic course, even when treated with one of the various effective treatments available. Lack of treatment effect could be due to Treatment Resistance (TR). Consensus on a definition for TR Anxiety Disorders (TR-AD) is highly needed as currently many different operationalizations are in use. Therefore, generalizability in current TR-AD research is suboptimal, hampering improvement of clinical care. The objective of this review is to evaluate the currently used definitions of TR-AD by performing a systematic review of available literature. Out of a total of n = 13 042, 62 studies that operationalized TR-AD were included. The current review confirms a lack of consensus on TR-AD criteria. In 62.9% of the definitions, TR was deemed present after the first treatment failure. Most studies (93.0%) required pharmacological treatment failures, whereas few (29.0%) required psychological treatment failures. However, criteria for what constitutes "treatment failure" were not provided in the majority of studies (58.1%). Definitions for minimal treatment duration ranged from at least 4 weeks to at least 6 months. Almost half of the TR-AD definitions (46.8%) required elevated anxiety severity levels in TR-AD. After synthesis of the results, the consensus definition considers TR-AD present after both at least one first-line pharmacological and one psychological treatment failure, provided for an adequate duration (at least 8 weeks) with anxiety severity remaining above a specified threshold. This definition could contribute to improving course prediction and identifying more targeted treatment options for the highly burdened subgroup of TR-AD patients.

Effect of high-frequency repetitive transcranial magnetic stimulation (rTMS) in patients with comorbid panic disorder and major depression

OBJECTIVE

To explore the role of dorsolateral prefrontal cortex (DLPFC) stimulation in the treatment of panic disorder with comorbid depression.

METHODS

The present study reports findings from retrospective analysis of 13 treatment-resistant patients diagnosed with comorbid panic disorder and depression, given 20 sessions of high-frequency transcranial magnetic stimulation (rTMS) over left-DLPFC over a period of 1 month.

RESULTS

There was a significant reduction in both the panic and depressive symptom severity, assessed by applying Panic Disorder Severity Scale (PDSS) and Hamilton Depression Rating Scale (HDRS) at baseline and after 20 sessions of rTMS. There was a 38% and 40% reduction of PDSS and HDRS scores, respectively, in the sample. The changes in PDSS and HDRS scores were not significantly correlated (ρ = -0.103, p = 0.737).

CONCLUSIONS

High-frequency rTMS delivered at left-DLPFC may have a potential role in treatment of comorbid panic disorder and depression. Future studies done on a larger sample in a controlled environment are required to establish its role.

To what extent is it possible to dissociate the anxiolytic and sedative/hypnotic properties of GABAA receptors modulators?

The relatively common view indicates a possible dissociation between the anxiolytic and sedative/hypnotic properties of benzodiazepines (BZs). Indeed, GABAA receptor (GABAAR) subtypes have specific cerebral distribution in distinct neural circuits. Thus, GABAAR subtype-selective drugs may be expected to perform distinct functions. However, standard behavioral test assays provide limited direction towards highlighting new action mechanisms of ligands targeting GABAARs. Automated behavioral tests, lack sensitivity as some behavioral characteristics or subtle behavioral changes of drug effects or that are not considered in the overall analysis (Ohl et al., 2001) and observation-based analyses are not always performed. In addition, despite the use of genetically engineered mice, any possible dissociation between the anxiolytic and sedative properties of BZs remains controversial. Moreover, the involvement the different subtypes of GABAAR subtypes in the anxious behavior and the mechanism of action of anxiolytic agents remains unclear since there has been little success in the pharmacological investigations so far. This raises the question of the involvement of the different subunits in anxiolytic-like and/or sedative effects; and the actual implication of these subunits, particularly, α-subunits in the modulation of sedation and/or anxiety-related disorders. This present review was prompted by several conflicting studies on the degree of involvement of these subunits in anxiolytic-like and/or sedative effects. To this end, we explored the GABAergic system, particularly, the role of different subunits containing synaptic GABAARs. We report herein the targeting gene encoding the different subunits and their contribution in anxiolytic-like and/or sedative actions, as well as, the mechanism underlying tolerance to BZs.

The POSE study - panic control treatment versus panic-focused psychodynamic psychotherapy under randomized and self-selection conditions: study protocol for a randomized controlled trial

BACKGROUND

Panic disorder with or without agoraphobia is a commonly occurring disorder affecting 2 to 3% of the population in Sweden. Untreated, panic disorder is a chronic condition that significantly increases the risk for psychiatric comorbidity, morbidity and mortality, employment difficulties, and healthcare utilization. Cognitive behavioral approaches are the recommended first-line treatment for panic disorder; however, many patients in routine care receive another evidence-based psychotherapy, including psychodynamic therapy. Allowing patients to choose among evidence-based approaches to panic disorder may improve outcomes and reduce overall health costs. Trials comparing the 'gold standard' treatment for panic disorder to other evidence-based psychotherapies are needed, and also trials that can separate patient preferences for treatment from randomization effects on outcome, disability and healthcare utilization in the longer term.

METHODS/DESIGN

A phase 2/3 doubly-randomized controlled trial carried out in routine care with 216 adults (aged 18 to 70 years) with a primary diagnosis of DSM-IV Panic Disorder (with or without Agoraphobia). Within each clinic, patients are randomized to self-selection, random assignment of treatment, or wait-list. Patients choose or are randomly assigned to either Panic Control Treatment or Panic-Focused Psychodynamic Psychotherapy. Primary outcomes are changes in panic symptom severity, occupational status, and sickness-related absences from work at post-treatment and 6, 12 and 24 months post-treatment. Secondary outcomes include changes in agoraphobic avoidance, psychiatric comorbidity, disability, and healthcare utilization. The study also employs elements of an effectiveness trial as therapist and service-related effects on outcome will be estimated. Putative change mechanisms for the two treatments are also assessed.

DISCUSSION

Cognitive behavioral and psychodynamic therapies are both evidence-based approaches that are routinely offered to panic disordered patients in Sweden. However, little is known about the relative effectiveness of these two approaches for panic/agoraphobia, work-related disability and healthcare utilization over the longer term. The current trial (POSE) also addresses the important but understudied issue of whether patient preference for a particular psychotherapeutic approach moderates outcome.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01606592 (registered 19 March 2012).

The reappraisal of benzodiazepines in the treatment of anxiety and related disorders

Benzodiazepines (BDZs) continue to be shrouded in controversy, mainly because of dependence associated with their long-term use and some of their side effects. Despite treatment recommendations favoring newer antidepressants, BDZs are still commonly prescribed for anxiety and related disorders. Recent studies have demonstrated that long-term use of BDZs for these conditions can be effective and safe and that BDZs can be combined with psychological therapy and antidepressants to produce optimal outcomes. Such findings, along with a failure to convincingly demonstrate the overall superiority of alternative pharmacotherapy for anxiety and related disorders, have given an impetus to a reconsideration of the role of BDZs. This article reviews BDZs and other pharmacotherapy options for anxiety and related disorders and suggests that treatment guidelines should acknowledge that BDZs can be used as first-line, long-term pharmacological treatment for panic disorder, generalized anxiety disorder and social anxiety disorder.

Reduced GABAergic inhibition in the basolateral amygdala and the development of anxiety-like behaviors after mild traumatic brain injury

Traumatic brain injury (TBI) is a major public health concern affecting a large number of athletes and military personnel. Individuals suffering from a TBI risk developing anxiety disorders, yet the pathophysiological alterations that result in the development of anxiety disorders have not yet been identified. One region often damaged by a TBI is the basolateral amygdala (BLA); hyperactivity within the BLA is associated with increased expression of anxiety and fear, yet the functional alterations that lead to BLA hyperexcitability after TBI have not been identified. We assessed the functional alterations in inhibitory synaptic transmission in the BLA and one mechanism that modulates excitatory synaptic transmission, the α7 containing nicotinic acetylcholine receptor (α7-nAChR), after mTBI, to shed light on the mechanisms that contribute to increased anxiety-like behaviors. Seven and 30 days after a mild controlled cortical impact (CCI) injury, animals displayed significantly greater anxiety-like behavior. This was associated with a significant loss of GABAergic interneurons and significant reductions in the frequency and amplitude of spontaneous and miniature GABAA-receptor mediated inhibitory postsynaptic currents (IPSCs). Decreases in the mIPSC amplitude were associated with reduced surface expression of α1, β2, and γ2 GABAA receptor subunits. However, significant increases in the surface expression and current mediated by α7-nAChR, were observed, signifying increases in the excitability of principal neurons within the BLA. These results suggest that mTBI causes not only a significant reduction in inhibition in the BLA, but also an increase in neuronal excitability, which may contribute to hyperexcitability and the development of anxiety disorders.

The role of alprazolam for the treatment of panic disorder in Australia

OBJECTIVE

To investigate the potential impact of increasing prescription rates of alprazolam for the treatment of panic disorder (PD) in Australia through a review of efficacy, tolerability and adverse outcome literature.

METHODS

Data were sourced by a literature search using MEDLINE, Embase, PsycINFO and a manual search of scientific journals to identify relevant articles. Clinical practice guidelines from the American Psychiatric Association, National Institute of Clinical Excellence, Royal Australian and New Zealand College of Psychiatrists and World Federation of Societies of Biological Psychiatry were sourced. Prescription data were sourced from Australian governmental sources.

RESULTS

Alprazolam has shown efficacy for control of PD symptoms, particularly in short-term controlled clinical trials, but is no longer recommended as a first-line pharmacological treatment due to concerns about the risks of developing tolerance, dependence and abuse potential. Almost no evidence is available comparing alprazolam to current first-line pharmacological treatment. Despite this, prescription rates are increasing. A number of potential issues including use in overdose and impact on car accidents are noted. conclusion: Although effective for PD symptoms in clinical trials, a number of potential issues may exist with use. Consideration of its future place in PD treatment in Australia may be warranted.

Prodynorphin gene deletion increased anxiety-like behaviours, impaired the anxiolytic effect of bromazepam and altered GABAA receptor subunits gene expression in the amygdala

This study evaluated the role of prodynorphin gene in the regulation of anxiety and associated molecular mechanisms. Emotional responses were assessed using the light-dark test, elevated plus maze and social interaction tests in prodynorphin knockout and wild-type mice. Corticotrophin releasing factor and proopiomelanocortin gene expressions in the hypothalamus were evaluated after restraint stress using in situ hybridization. The anxiolytic efficacy of bromazepam and GABA(A) receptor subunits gene expression in the amygdala were also assessed in both genotypes. The deletion of prodynorphin increased anxiety-like behaviours and proopiomelanocortin gene expression in the arcuate nucleus (two-fold). Moreover, the anxiolytic action of bromazepam was significantly attenuated in the mutant mice. Decreased GABA(A)γ(2) and increased GABA(A)β(2) gene expression receptor subunits were found in the amygdala of prodynorphin knockout mice. These results indicate that deletion of prodynorphin gene is associated with increased anxiety-like behaviours, enhanced sensibility response to stress stimuli, reduced anxiolytic efficacy of bromazepam and altered expression of the GABA(A) receptor subunits.

World Federation of Societies of Biological Psychiatry (WFSBP) guidelines for the pharmacological treatment of anxiety, obsessive-compulsive and post-traumatic stress disorders - first revision

In this report, which is an update of a guideline published in 2002 (Bandelow et al. 2002, World J Biol Psychiatry 3:171), recommendations for the pharmacological treatment of anxiety disorder, obsessive-compulsive disorder (OCD) and post-traumatic stress disorder (PTSD) are presented. Since the publication of the first version of this guideline, a substantial number of new randomized controlled studies of anxiolytics have been published. In particular, more relapse prevention studies are now available that show sustained efficacy of anxiolytic drugs. The recommendations, developed by the World Federation of Societies of Biological Psychiatry (WFSBP) Task Force for the Pharmacological Treatment of Anxiety, Obsessive-Compulsive and Post-traumatic Stress Disorders, a consensus panel of 30 international experts, are now based on 510 published randomized, placebo- or comparator-controlled clinical studies (RCTs) and 130 open studies and case reports. First-line treatments for these disorders are selective serotonin reuptake inhibitors (SSRIs), serotonin-noradrenaline reuptake inhibitors (SNRIs) and the calcium channel modulator pregabalin. Tricyclic antidepressants (TCAs) are equally effective for some disorders, but many are less well tolerated than the SSRIs/SNRIs. In treatment-resistant cases, benzodiazepines may be used when the patient does not have a history of substance abuse disorders. Potential treatment options for patients unresponsive to standard treatments are described in this overview. Although these guidelines focus on medications, non-pharmacological were also considered. Cognitive behavioural therapy (CBT) and other variants of behaviour therapy have been sufficiently investigated in controlled studies in patients with anxiety disorders, OCD, and PTSD to support them being recommended either alone or in combination with the above medicines.

Treatment of panic disorder: recent developments and current status

Panic disorder is a commonly encountered condition in general medical practice and in various medical settings. It is important for all medical practitioners to be able to recognize this disorder, provide patients with basic information and medical advice, and depending on the specific circumstances, to refer patients for appropriate treatment by primary care physicians, psychiatrists and/or clinical psychologists. This article reviews the developments in the treatment of panic disorder, focusing on the major treatment modalities of pharmacotherapy and cognitive-behavior therapy, as well as their combinations. In addition to providing information on current treatments for panic disorder and the main underlying treatment issues, the article identifies areas where improvements need to be made and areas where much research has been conducted in recent years. These include simplified modes of delivery of cognitive-behavior therapy, optimal ways of combining medications with cognitive-behavior therapy, and minimizing the risk of recurrence after the cessation of treatment.

Pharmacological management of panic disorder

Panic disorder (PD) is a disabling condition which appears in late adolescence or early adulthood and affects more frequently women than men. PD is frequently characterized by recurrences and sometimes by a chronic course and, therefore, most patients require long-term treatments to achieve remission, to prevent relapse and to reduce the risks associated with comorbidity. Pharmacotherapy is one of the most effective treatments of PD. In this paper, the pharmacological management of PD is reviewed. Many questions about this effective treatment need to be answered by the clinician and discussed with the patients to improve her/his collaboration to the treatment plan: which is the drug of choice; when does the drug become active; which is the effective dose; how to manage the side effects; how to manage nonresponse; and how long does the treatment last. Moreover, the clinical use of medication in women during pregnancy and breastfeeding or in children and adolescents was reviewed and its risk-benefit balance discussed.

History of depressive and anxiety disorders and paroxetine response in patients with irritable bowel syndrome: post hoc analysis from a placebo-controlled study

OBJECTIVE

Although irritable bowel syndrome (IBS) is highly comorbid with depressive and anxiety disorders, information on the clinical implications of this comorbidity is limited. We investigated whether a history of depressive and/or anxiety disorders was associated with response to treatment in a double-blind, randomized, placebo-controlled trial of paroxetine controlled release (CR) in IBS.

METHOD

Seventy-two IBS subjects (diagnosed using Rome II criteria) were recruited from August 2003 to November 2005 and randomly assigned to receive flexibly dosed paroxetine CR (dose, 12.5-50 mg/day) or placebo for 12 weeks. The Mini-International Neuropsychiatric Interview (MINI-Plus version) was used to ascertain current (exclusionary) or past diagnoses of depressive and anxiety disorders. Subjective depression, anxiety, and stress were assessed at entry and throughout the trial using the Beck Depression Inventory (BDI), Beck Anxiety Inventory (BAI), and Perceived Stress Scale (PSS). Severity of IBS symptoms was determined by the Composite Pain Score (CPS), administered via Interactive Voice Response System, and the Clinical Global Impressions scale (CGI). The primary outcome was treatment response defined as ≥ 25% reduction in CPS from randomization to end of treatment. A post hoc analysis (multivariate logistic regression) was done to evaluate whether a history of depressive and/or anxiety disorder was associated with response to medication.

RESULTS

Baseline demographic and clinical characteristics (CPS, BDI, BAI, PSS, CGI scores) were similar between groups (history of depressive/anxiety disorder vs. no history). In multivariate logistic regression analysis, treatment response was not predicted by history of depressive and/or anxiety disorder (OR = 0.58, CI = 0.29 to 1.68, p = .32) or drug status (paroxetine CR vs. placebo) (OR = 1.26, CI = 0.68 to 3.21, p = .19). Drug status was significantly associated with the secondary outcome variable of treatment response as defined by a CGI improvement score of 1 to 2 (OR = 12.14, CI = 2.9 to 48.4, p < .001). Paroxetine CR was safe and well tolerated during the study.

CONCLUSIONS

History of depressive and/or anxiety disorder was not associated with response of IBS symptoms to paroxetine CR. Conclusions are limited due to insufficient statistical power. Further research is needed to clarify the role of selective serotonin reuptake inhibitors in the treatment of IBS and to elucidate the treatment ramifications of comorbid psychiatric disorders.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00610909.

The therapeutic potential of escitalopram in the treatment of panic disorder

Panic disorder is a chronic and disabling condition that is often accompanied by other psychiatric and medical conditions. The serotonin reuptake inhibitors (SSRIs) and serotonin-norepinephrine reuptake inhibitors (SNRIs) have been used effectively with panic disorder (PD) and conditions in which panic attacks frequently occur. Escitalopram is the most selective SSRI and a variety of evidence suggests it is of great value in the treatment of panic disorder. In this paper, we review the theoretical and practical implications of its use.

Repetitive Transcranial Magnetic Stimulation (rTMS) in the treatment of panic disorder (PD) with comorbid major depression

BACKGROUND

Studies suggest that the dorsolateral prefrontal cortex (DLPFC) participates in neural circuitry that is dysregulated in Panic Disorder (PD) and Major Depressive Disorder (MDD). We tested whether low-frequency repetitive Transcranial Magnetic Stimulation (rTMS) could normalize the overactivity of right frontal regions and thereby improve symptoms.

METHODS

Six patients with PD and comorbid MDD were treated with daily active 1-Hz rTMS to the right DLPFC for 2 weeks in this open-label trial.

RESULTS

Clinical improvements were apparent as early as the first week of treatment. After the second week, 5/6 of patients showed improvements in panic and anxiety, and 4/6 showed a decrease in depression, with sustained improvement at 6 months of follow-up. Right hemisphere resting motor threshold increased significantly after rTMS.

LIMITATIONS

Limitations of this study are the open design and the small sample size.

CONCLUSIONS

Slow rTMS to the right DLPFC resulted in significant clinical improvement and reduction of ipsilateral motor cortex excitability. Replications in larger sample will help to clarify the relevance of this preliminary data and to define the potential role of right DLPFC rTMS in panic with major depression.

Preliminary results of an open label study of heart rate variability biofeedback for the treatment of major depression

Major depressive disorder (MDD) is a common mood disorder that can result in significant discomfort as well as interpersonal and functional disability. A growing body of research indicates that autonomic function is altered in depression, as evidenced by impaired baroreflex sensitivity, changes in heart rate, and reduced heart rate variability (HRV). Decreased vagal activity and increased sympathetic arousal have been proposed as major contributors to the increased risk of cardiovascular mortality in participants with MDD, and baroreflex gain is decreased.

STUDY OBJECTIVES

To assess the feasibility of using HRV biofeedback to treat major depression.

DESIGN

This was an open-label study in which all eleven participants received the treatment condition. Participants attended 10 weekly sessions. Questionnaires and physiological data were collected in an orientation (baseline) session and Treatment Sessions 1, 4, 7 and 10.

MEASUREMENTS AND RESULTS

Significant improvements were noted in the Hamilton Depression Scale (HAM-D) and the Beck Depression Inventory (BDI-II) by Session 4, with concurrent increases in SDNN, standard deviation of normal cardiac interbeat intervals) an electrocardiographic estimate of overall measure of adaptability. SDNN decreased to baseline levels at the end of treatment and at follow-up, but clinically and statistically significant improvement in depression persisted. Main effects for task and session occurred for low frequency range (LF) and SDNN. Increases in these variables also occurred during breathing at one's resonant frequency, which targets baroreflex function and vagus nerve activity, showing that subjects performed the task correctly.

CONCLUSIONS

HRV biofeedback appears to be a useful adjunctive treatment for the treatment of MDD, associated with large acute increases in HRV and some chronic increases, suggesting increased cardiovagal activity. It is possible that regular exercise of homeostatic reflexes helps depression even when changes in baseline HRV are smaller. A randomized controlled trial is warranted.

Pharmacotherapy augmentation strategies in treatment-resistant anxiety disorders

BACKGROUND

A large proportion of patients with anxiety disorders fail to respond to first-line medication interventions, despite evidence of the effectiveness of these agents.

OBJECTIVES

To assess the effects of medication versus placebo augmentation in the treatment of patients with anxiety disorders who have failed to respond adequately to first-line drug therapies.

SEARCH STRATEGY

The Cochrane Depression, Anxiety & Neurosis Group (CCDAN) specialised registers (CCDANCTR-Studies and CCDANCTR-References) were searched on 3/8/2005, MEDLINE (January 1966 to July 2005) and PsycINFO (1966 to 2005, Part A). Unpublished trials were identified through the Controlled Trials database and the National Institute of Health's Computer Retrieval of Information on Scientific Projects (CRISP) service (1972 to 2005). Additional studies in any language were sought in reference lists of retrieved articles.

SELECTION CRITERIA

All randomised controlled trials (RCTs) of the medication augmentation of pharmacotherapy for treatment resistant anxiety disorders.

DATA COLLECTION AND ANALYSIS

Two raters independently assessed RCTs for inclusion in the review, collated trial data, and assessed trial quality. Investigators were contacted to obtain missing data. Summary statistics were stratified by class of augmentation agent and anxiety disorder. Overall effect estimates were calculated using a random-effects model, heterogeneity was assessed and subgroup/sensitivity analyses were undertaken.

MAIN RESULTS

Twenty eight short-term (average of seven weeks) randomised controlled trials (740 participants) were included in the review, 20 of which investigated augmentation of medication for treatment-resistant obsessive compulsive disorder (OCD). Summary statistics for responder status from nine trials demonstrate overall superiority of a variety of medication agents to placebo (relative risk of non-response (RR) 3.16, 95% CI 1.08 to 9.23). Similarly, symptom severity was significantly reduced in the medication groups, relative to placebo (number of trials (N) = 14, standardised mean difference (SMD) -0.87, 95% CI -1.37 to -0.36). There is no evidence of a difference between medication and placebo in total dropout rate, or in the number of dropouts due to adverse events.

AUTHORS' CONCLUSIONS

Medication augmentation can be an effective and well-tolerated short-term treatment strategy for non-responders to first-line pharmacotherapy of anxiety disorders. However, any conclusions must be tentative in view of methodological and clinical heterogeneity, and the fact that much of the relevant database is based on antipsychotic augmentation trials in OCD patients resistant to serotonin reuptake inhibitors (SRIs). Additional data are needed to address several areas, including the efficacy of augmentation over the longer-term, and the value of medication augmentation in comparison to other strategies (e.g. switching medication, adding psychotherapy).

Treatment-resistant anxiety disorders

Several epidemiological studies confirmed that Anxiety Disorders as a group are the most prevalent psychiatric conditions in the United States. The importance of these conditions is underlined by the fact that they cause significant disability, poor quality of life, alcohol and drug abuse. Anxiety disorders are treatable conditions and respond to the front-line interventions such as serotonin reuptake inhibitors and cognitive behavioral therapy. However, only about 60% of patients respond to those treatments to any significant degree. Many still have residual symptoms or stay treatment refractory. The group of anxiety patients that is resistant to the treatment has been shown to have very poor quality of life and have highest rate of suicidal attempts than any other disorders. Many biological, treatment specific and social factors are affecting treatment resistance. In this paper, we are attempting to review reasons for the treatment resistance. In addition, we would like to review current strategies that could be helpful in reducing treatment resistance and aiding people chronically suffering from these severe and disabling conditions.

Issues in the pharmacological treatment of anxiety disorders

OBJECTIVE

To review the most salient issues in the pharmacotherapy of anxiety disorders. These pertain to means of achieving greater efficacy, accelerating the onset of therapeutic action, improving side-effect profile and tolerability, decreasing the propensity to induce therapeutic dependence and achieving better long-term outcome.

CONCLUSIONS

By and large, pharmacological agents with greater efficacy in anxiety disorders have yet to be developed. Several strategies have been used with some success to make medications for anxiety disorders work faster and to lessen their side-effect burden. The field of psychopharmacology has yet to find ways of lessening or eliminating the problem of therapeutic drug dependence and, even more so, of minimizing the risk of relapse following the cessation of medication.

Potential effectiveness and safety of olanzapine in refractory panic disorder

Panic disorder is a common and disabling psychiatric disorder. Despite treatment advances, refractory panic disorder requires novel interventions. One such pharmacologic intervention with theoretical and case study support includes olanzapine, a thienobenzodiazepine medication currently approved for schizophrenia in the United States. Ten people with refractory DSM-IV diagnosed panic disorder completed an 8-week, open-label, flexible-dose clinical trial. Baseline, in-treatment, and end-of-treatment data for panic attacks, anticipatory anxiety, phobic avoidance, and impairment were collected. Data were analyzed using SPSS software. Refractory panic disorder patients required a wide dose range averaging 12.3 mg/day of olanzapine to significantly improve or ablate panic attacks. On the average, number of attacks decreased from 6.1/week at baseline to 1.1/week at the end of treatment, and anticipatory anxiety from 32% of the day to 8% of the day. At treatment end, 5 of 10 participants (50%) were panic free, 4 (40%) had one attack in the previous week, 1 (10%) had seven attacks in the previous week, and 6 of 10 participants (60%) were anticipatory anxiety free. There were also statistically and clinically significant improvements in impairment over the course of the trial. There were no significant changes in vital signs, emergent side effects, or average weight, although 6 of 10 people did gain weight. Olanzapine is potentially effective and safe in panic disorder. Due to study limitations, further clinical trials are needed to demonstrate effectiveness.

Results of a naturalistic longitudinal study of benzodiazepine and SSRI use in the treatment of generalized anxiety disorder and social phobia

The past decade has brought major new developments in the psychopharmacologic management of generalized anxiety disorder and social phobia. We examined medication-prescribing patterns for the treatment of these anxiety disorders for 12 years to assess changes in patients' anti-anxiety psychotropic medication usage during that period of evolving practice guidelines. We examined psychotropic medication use in 305 patients with generalized anxiety disorder and 232 with social phobia enrolled in the Harvard/Brown Anxiety Disorders Research Project (HARP), a prospective, longitudinal study of anxiety disorders. Psychotropic treatment patterns seem to have remained relatively stable over 12 years with benzodiazepines the medications most commonly used for both generalized anxiety disorder and social phobia. Comparatively, selective serotonin reuptake inhibitor (SSRI) and venlafaxine usage as stand-alone medications for these disorders remained low throughout the follow-up period. At the 12-year follow-up, 24% of patients with generalized anxiety disorder and 30% of patients with social phobia were utilizing neither an SSRI/selective norepinephrine reuptake inhibitor (SNRI) nor a benzodiazepine. Treatment recommendations for use of SSRIs and venlafaxine in the management of generalized anxiety disorder and social phobia initially promulgated in 1998 had a modest impact on changes in psychopharmacologic practice 4-5 years later. Difficulties in the implementation of treatment guidelines are discussed.

Variability in the benzodiazepine response of serotonin 5-HT1A receptor null mice displaying anxiety-like phenotype: evidence for genetic modifiers in the 5-HT-mediated regulation of GABA(A) receptors

Benzodiazepines (BZs) acting as modulators of GABA(A) receptors (GABA(A)Rs) are an important group of drugs for the treatment of anxiety disorders. However, a large inter-individual variation in BZ sensitivity occurs in the human population with some anxiety disorder patients exhibiting diminished sensitivity to BZ and reduced density of GABA(A)Rs. The mechanism underlying BZ treatment resistance is not known, and it is not possible to predict whether an anxiety patient will respond to BZ. 5-hydroxytryptamine1A receptor (5-HT1AR) null mice (R-/-) on the Swiss-Webster (SW) background reproduce several features of BZ-resistant anxiety; they exhibit anxiety-related behaviors, do not respond to BZ, have reduced BZ binding, and have decreased expression of the major GABA(A)R subunits alpha1 and alpha2. Here, we show that R-/- mice on the C57Bl6 (B6) background also have anxiety phenotype, but they respond to BZ and have normal GABA(A)R subunit expression. This indicates that the 5-HT1AR-mediated regulation of GABA(A)R alpha subunit expression is subject to genetic modification. Hybrid SW/B6-R-/- mice also exhibit BZ-resistant anxiety, suggesting that SW mice carry a genetic modifier, which mediates the effect of the 5-HT1AR on the expression of GABA(A)Ralpha subunits. In addition, we show that this genetic interaction in SW mice operates early in postnatal life to influence the expression of GABA(A)R alpha subunits at the transcriptional level. These data indicate that BZ-resistant anxiety results from a developmental arrest of GABA(A)R expression in SW-R-/- mice, and a similar mechanism may be responsible for the BZ insensitivity of some anxiety patients.

Spontaneous treatment discontinuation in panic disorder patients treated with antidepressants

OBJECTIVE

We examined the relationships between long-term treatment response, side-effects and drug discontinuation in panic disorder (PD)-agoraphobia.

METHOD

A total of 326 patients were naturalistically treated with antidepressants and followed for a period of 3 years. All patients were evaluated by means of the Panic Disorder/Agoraphobia Interview and the Longitudinal Interview Follow-up Examination (LIFE-UP).

RESULTS

A total of 179 patients interrupted pharmacological treatment. Among them, 26.8% were not traceable; 36.9% had deemed further contact with the psychiatrist unnecessary because of remission. Other reasons for interruption were: ineffectiveness (18.4%), side-effects (10.6%) and personal reasons (7.3%). Patients who interrupted pharmacological treatment because of symptom remission remained in the study for a longer period than those patients who interrupted their treatment because of inefficacy.

CONCLUSION

In the long-term treatment of PD with antidepressants, a high percentage of patients who have achieved symptom remission tend to default from further treatment; adherence to long-term treatment with antidepressants was predicted by severe and long-lasting symptomatology.

World Federation of Societies of Biological Psychiatry (WFSBP) guidelines for the pharmacological treatment of anxiety, obsessive-compulsive and posttraumatic stress disorders

In this report, recommendations for the pharmacological treatment of anxiety and obsessive-compulsive disorders are presented, based on available randomized, placebo- or comparator-controlled clinical studies. Selective serotonin reuptake inhibitors (SSRIs) are the first-line treatment for panic disorder. Tri2-cyclic antidepressants (TCAs) are equally effective, but they are less well tolerated than the SSRIs. In treatment-resistant cases, benzodiazepines like alprazolam may be used when the patient does not have a history of dependency and tolerance. Due to possible serious side effects and interactions with other drugs and food components, the irreversible monamine oxidase inhibitor (MAOI) phenelzine should be used only when first-line drugs have failed. In generalised anxiety disorder, venlafaxine and SSRIs can be recommended, while buspirone and imipramine may be alternatives. For social phobia, SSRIs are recommended for the first line, and MAOIs, moclobemide and benzodiazepines as second line. Obsessive-compulsive disorder is best treated with SSRIs or clomipramine.

Heart rate variability as predictor of nonresponse to mirtazapine in panic disorder: a preliminary study

Using spectral analysis of heart rate, several studies have shown that panic disorder patients are characterized by a reduced heart rate variability (HRV), indicative of abnormalities in autonomous nervous system (ANS) function. We recently reported that patients with panic disorder, who did not respond to pharmacotherapy, were characterized at baseline by a higher heart rate. In this study, ANS functioning is investigated as a possible predictor of nonresponse to pharmacotherapy. Twenty-eight medication-free panic disorder patients entered a 12-week open-label treatment study with mirtazapine. Five-minute HRV recordings were obtained before treatment and were analysed using spectral analysis. The data of 17 patients could be used. The total spectrum and low frequency power of responders to mirtazapine were significantly higher than those of nonresponders. Our findings suggest that nonresponders to short-term mirtazapine treatment are characterized at baseline by a lowered output of the ANS. The results are preliminary in view of the small sample studied.

The prediction of nonresponse to pharmacotherapy in panic disorder: a review

Several effective pharmacotherapeutic treatments exist for panic disorder; however, not all patients respond to treatment: between 20% to 40% are non-responders. Recent studies have reported several predictors of nonresponse to pharmacotherapy. In this review two questions are addressed: is there consensus with respect to predictors of nonresponse and are there any differences between short-term and long-term predictors? In this review both short-term and long-term outcome studies are discussed. Studies were included if at least DSM-III criteria were used and baseline variables were investigated as possible predictor of response, or nonresponse, to pharmacotherapy. Of each clinical predictor, tallies were made of the particular predictors employed and of those predictors that predicted nonresponse. It appears that a long duration of illness and severe agoraphobic avoidance are robust predictors of nonresponse, particularly in long-term studies. Personality disorders, or even personality traits, are possibly the most robust predictors of nonresponse. Several factors appear to be robust predictors of nonresponse: factors that are present before treatment and exert their influence on short-term and long-term treatment outcome. Prospective studies are needed to further investigate these factors and to test whether it is viable to intervene in an attempt to increase treatment response.

Anxiety Disorders in Neurologic Illness

Anxiety disorders frequently occur in individuals with neurologic illness. Anxiety may be a symptom of or a reaction to the neurologic disorder, a medication side effect, or a comorbid condition. The most common anxiety disorders seen in neurologic patients are panic disorder, generalized anxiety disorder, social phobia, and obsessive-compulsive disorder (OCD). Very often, these conditions go unrecognized (and therefore untreated) or are attributed to being a normal response to having a neurologic illness. However, if they are not treated, anxiety disorders can significantly increase morbidity and mortality in neurologic patients. Selective serotonin reuptake inhibitors (SSRIs) should be considered the first-line of pharmacologic treatment, because they offer a broad spectrum of efficacy in the anxiety disorders, are generally well tolerated, and are effective in treating comorbid depression. Benzodiazepines, although most effective for acute anxiety, are now considered adjunctive or second-line treatments. Cognitive behavioral therapy and other behavioral treatments are effective in the treatment of anxiety disorders. They should be considered primary treatments for patients who cannot tolerate or prefer not to take medications.

Group cognitive-behavior therapy for patients failing to respond to pharmacotherapy for panic disorder: a clinical case series

The last decade has brought exciting advances to the treatment of panic disorder and agoraphobia, and a variety of cognitive-behavioral and pharmacologic treatment strategies offer clear benefit to patients. Nonetheless, treatment nonresponse continues to be a chronic problem, and additional strategies are needed to aid patients who do not respond fully to initial interventions. In the present study, we use 'services' research to document the clinical response of pharmacotherapy nonresponders to a standard program of brief, group cognitive-behavioral therapy. Patients responded well, regardless of whether they had received a full, adequate trial of pharmacotherapy. In addition to its application as an initial treatment for panic disorder, routine application of cognitive-behavioral therapy in pharmacologic treatment algorithms is encouraged, with attention to referral of pharmacotherapy nonresponders to cognitive-behavioral therapy.