Pharmacotherapy for post-traumatic stress disorder: systematic review and meta-analysis

Contribution of Hippocampal 5-HT3 Receptors in Hippocampal Autophagy and Extinction of Conditioned Fear Responses after a Single Prolonged Stress Exposure in Rats

One of the hypotheses about the pathogenesis of posttraumatic stress disorder (PTSD) is the dysfunction of serotonin (5-HT) neurotransmission. While certain 5-HT receptor subtypes are likely critical for the symptoms of PTSD, few studies have examined the role of 5-HT3 receptor in the development of PTSD, even though 5-HT3 receptor is critical for contextual fear extinction and anxiety-like behavior. Therefore, we hypothesized that stimulation of 5-HT3 receptor in the dorsal hippocampus (DH) could prevent hippocampal autophagy and the development of PTSD-like behavior in animals. To this end, we infused SR57227, selective 5-HT3 agonist, into the DH after a single prolonged stress (SPS) treatment in rats. Three weeks later, we evaluated the effects of this pharmacological treatment on anxiety-related behaviors and extinction of contextual fear memory. We also accessed hippocampal autophagy and the expression of 5-HT3A subunit, Beclin-1, LC3-I, and LC3-II in the DH. We found that SPS treatment did not alter anxiety-related behaviors but prolonged the extinction of contextual fear memory, and such a behavioral phenomenon was correlated with increased hippocampal autophagy, decreased 5-HT3A expression, and increased expression of Beclin-1 and LC3-II/LC3-I ratio in the DH. Furthermore, intraDH infusions of SR57227 dose-dependently promoted the extinction of contextual fear memory, prevented hippocampal autophagy, and decreased expression of Beclin-1 and LC3-II/LC3-I ratio in the DH. These results indicated that 5-HT3 receptor in the hippocampus may play a critical role in the pathogenesis of hippocampal autophagy, and is likely involved in the pathophysiology of PTSD.

The role of GluN2B-containing NMDA receptors in short- and long-term fear recall

N-methyl-d-aspartate (NMDA) receptors are crucial synaptic elements in long-term memory formation, including the associative learning of fearful events. Although NMDA blockers were consistently shown to inhibit fear memory acquisition and recall, the clinical use of general NMDA blockers is hampered by their side effects. Recent studies revealed significant heterogeneity in the distribution and neurophysiological characteristics of NMDA receptors with different GluN2 (NR2) subunit composition, which may have differential role in fear learning and recall. To investigate the specific role of NMDA receptor subpopulations with different GluN2 subunit compositions in the formation of lasting traumatic memories, we contrasted the effects of general NMDA receptor blockade with GluN2A-, GluN2B-, and GluN2C/D subunit selective antagonists (MK-801, PEAQX, Ro25-6981, PPDA, respectively). To investigate acute and lasting consequences, behavioral responses were investigated 1 and 28days after fear conditioning. We found that MK-801 (0.05 and 0.1mg/kg) decreased fear recall at both time points. GluN2B receptor subunit blockade produced highly similar effects, albeit efficacy was somewhat smaller 28days after fear conditioning. Unlike MK-801, Ro25-6981 (3 and 10mg/kg) did not affect locomotor activity in the open-field. In contrast, GluN2A and GluN2C/D blockers (6 and 20mg/kg PEAQX; 3 and 10mg/kg PPDA, respectively) had no effect on conditioned fear recall at any time point and dose. This sharp contrast between GluN2B- and other subunit-containing NMDA receptor function indicates that GluN2B receptor subunits are intimately involved in fear memory formation, and may provide a novel pharmacological target in post-traumatic stress disorder or other fear-related disorders.

Pharmacological treatment of refugees with trauma-related disorders: What do we know today?

There is a dearth of evidence on the effectiveness of pharmacological treatment for refugees with trauma-related disorders. The present paper provides an overview of available literature on the subject and discusses the transferability of results from studies on other groups of patients with post traumatic stress disorder (PTSD). We conducted a systematic review of published treatment outcome studies on PTSD and depression among refugees. Fifteen studies were identified and reviewed. Most studies focused on the use of antidepressants. Included studies differed widely in method and quality. The majority were observational studies and case studies. Small sample sizes limited the statistical power. Few studies reported effect sizes, confidence intervals, and statistical significance of findings. No specific pharmacological treatment for PTSD among refugees can be recommended on the basis of the available literature. There is a need for well-designed clinical trials, especially with newer antidepressants and antipsychotics. Until such studies are available, clinical practice and design of trials can be guided by results from studies of other groups of PTSD patients, although differences in pharmacogenetics, compliance, and trauma reactions may affect the direct transferability of results from studies on nonrefugee populations.

PTSD in Court II: Risk factors, endophenotypes, and biological underpinnings in PTSD

The second article in the series of three for the journal on "PTSD in Court" especially concerns the biological bases that have been found to be associated with PTSD (posttraumatic stress disorder). The cohering concepts in this section relate to risk factors; candidate genes; polygenetics; "gene×environment" interactions; epigenetics; endophenotypes; biomarkers; and connective networks both structurally and functionally (in terms of intrinsic connectivity networks, ICNs, including the DMN, SN, and CEN; that is, default mode, salience, and central executive networks, respectively). Risk factors related to PTSD include pre-event, event- and post-event ones. Some of the genes related to PTSD include: FKBP5, 5-HTTLPR, and COMT (which are, respectively, FK506-binding protein 5 gene, serotonin-transporter linked polymorphic region, catechol-O-methyl-transferase). These genetic findings give an estimate of 30% for the genetic influence on PTSD. The typical brain regions involved in PTSD include the amygdala, hippocampus, and prefrontal cortex, along with the insula. Causal models of behavior are multifactorial and biopsychosocial, and these types of models apply to PTSD, as well. The paper presents a multilevel systems model of psychopathology, including PTSD, which involves three levels - a top-down psychological construct one, a bottom-up symptom connection one, and a middle one involving symptom appraisal. Legally, causality refers to the event at issue needing to meet the bar of being materially contributory to the outcome. Finally, this section of the article reviews empirically-supported therapies for PTSD and the dangers of not receiving treatment for it.

Accelerated Resolution Therapy (ART): a Review and Research to Date

PURPOSE OF REVIEW

To describe and summarize published research on accelerated resolution therapy (ART), a promising and relatively new psychotherapy with the potential to offer rapid and effective resolution of a wide range of psychiatric symptoms. Unlike most evidence-based psychotherapies, ART is a predominately imaginative therapy that relies upon the rescripting of distressing events and metaphors as one of its key therapeutic elements.

RECENT FINDINGS

The number of studies conducted on ART is limited, primarily consisting of one randomized, controlled trial (RCT) with 57 subjects and two large cohort studies involving 80 and 117 subjects, respectively. However, a growing body of research in the neuroscience field involving the initial creation (consolidation), activation, and reconsolidation of memories may also be relevant and is summarized herein. ART appears to be an effective, efficient, and versatile form of psychotherapy. Future studies, particularly high-quality RCTs, are needed to more fully understand the potential reach of this promising therapeutic modality.

Marijuana and other cannabinoids as a treatment for posttraumatic stress disorder: A literature review

Posttraumatic stress disorder (PTSD) is common in the general population, yet there are limitations to the effectiveness, tolerability, and acceptability of available first-line interventions. We review the extant knowledge on the effects of marijuana and other cannabinoids on PTSD. Potential therapeutic effects of these agents may largely derive from actions on the endocannabinoid system and we review major animal and human findings in this area. Preclinical and clinical studies generally support the biological plausibility for cannabinoids' potential therapeutic effects, but underscore heterogeneity in outcomes depending on dose, chemotype, and individual variation. Treatment outcome studies of whole plant marijuana and related cannabinoids on PTSD are limited and not methodologically rigorous, precluding conclusions about their potential therapeutic effects. Reported benefits for nightmares and sleep (particularly with synthetic cannabinoid nabilone) substantiate larger controlled trials to determine effectiveness and tolerability. Of concern, marijuana use has been linked to adverse psychiatric outcomes, including conditions commonly comorbid with PTSD such as depression, anxiety, psychosis, and substance misuse. Available evidence is stronger for marijuana's harmful effects on the development of psychosis and substance misuse than for the development of depression and anxiety. Marijuana use is also associated with worse treatment outcomes in naturalistic studies, and with maladaptive coping styles that may maintain PTSD symptoms. Known risks of marijuana thus currently outweigh unknown benefits for PTSD. Although controlled research on marijuana and other cannabinoids' effects on PTSD remains limited, rapid shifts in the legal landscape may now enable such studies, potentially opening new avenues in PTSD treatment research.

Novel pharmacological treatment strategies for posttraumatic stress disorder

INTRODUCTION

A wide range of medications have been studied for posttraumatic stress disorder (PTSD) and a number are registered for this indication. Nevertheless, current pharmacotherapies are only partially effective in some patients, and are minimally effective in others. Thus novel treatment avenues need to be explored. Areas covered: In considering novel pharmacological agents for the treatment of PTSD, this paper takes a translational approach. We outline how advances in our understanding of the underlying neurobiology of PTSD may inform the identification of potential new treatment targets, including glutamatergic, noradrenergic and opioid pathways. Expert commentary: Continued investigation of the neural substrates and signalling pathways involved in responses to trauma may inform the development of novel treatment targets for future drug development for PTSD. However, the translation of preclinical findings to clinical practice is likely to be complex and gradual.

Neurobiology of comorbid post-traumatic stress disorder and alcohol-use disorder

Post-traumatic stress disorder (PTSD) and alcohol-use disorder (AUD) are highly comorbid in humans. Although we have some understanding of the structural and functional brain changes that define each of these disorders, and how those changes contribute to the behavioral symptoms that define them, little is known about the neurobiology of comorbid PTSD and AUD, which may be due in part to a scarcity of adequate animal models for examining this research question. The goal of this review is to summarize the current state-of-the-science on comorbid PTSD and AUD. We summarize epidemiological data documenting the prevalence of this comorbidity, review what is known about the potential neurobiological basis for the frequent co-occurrence of PTSD and AUD and discuss successes and failures of past and current treatment strategies. We also review animal models that aim to examine comorbid PTSD and AUD, highlighting where the models parallel the human condition, and we discuss the strengths and weaknesses of each model. We conclude by discussing key gaps in our knowledge and strategies for addressing them: in particular, we (1) highlight the need for better animal models of the comorbid condition and better clinical trial design, (2) emphasize the need for examination of subpopulation effects and individual differences and (3) urge cross-talk between basic and clinical researchers that is reflected in collaborative work with forward and reverse translational impact.

Treatment of trauma-affected refugees with venlafaxine versus sertraline combined with psychotherapy - a randomised study

BACKGROUND

The prevalence of trauma-related psychiatric disorders is high among refugees. Despite this, little is known about the effect of pharmacological treatment for this patient group. The objective of the present study was therefore to examine differences in the effects of venlafaxine and sertraline on Post-Traumatic Stress Disorder (PTSD), depression and functional impairment in trauma-affected refugees.

METHODS

The study was a randomised pragmatic trial comparing venlafaxine and sertraline in combination with psychotherapy and social counselling. PTSD symptoms were measured on the Harvard Trauma Questionnaire - part IV, which was the primary outcome measure. Other outcome measures included: Hopkins Symptom Check List-25 (depression and anxiety), Social Adjustment Scale - short version (social functioning), WHO-5 Well-being Index (quality of life), Crisis Support Scale (support from social network), Sheehan Disability Scale (disability in three areas of functioning), Hamilton Depression and Anxiety scale, the somatisation items of the Symptoms Checklist-90, Global Assessment of Functioning scales and the summarised score of pain in four body areas rated on visual analogue scales.

RESULTS

Two hundred seven adult refugee patients were included in the trial (98 in the venlafaxine and 109 in the sertraline group). Of these, 195 patients were eligible for intention-to-treat analyses. Small but significant pre-treatment to post-treatment differences were found on the Harvard Trauma Questionnaire and a number of other ratings in both groups. On the primary outcome measure, no difference was found in treatment effect between the sertraline and venlafaxine group. A significant group difference was found in favour of sertraline on the Sheehan Disability Scale.

CONCLUSION

Sertraline had a slightly better outcome than venlafaxine on some of the secondary outcome measures, but not on the primary outcome measure. Furthermore, a higher percentage of dropouts was found in the venlafaxine group compared to the sertraline group. Although this could indicate that sertraline was better tolerated, which is supported by other studies, a final conclusion on tolerability cannot be drawn from the current study due to lack of systematic reporting of side effects.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01569685 . Registration date: 28/2/12.

Pharmacotherapy of post-traumatic stress disorder: going beyond the guidelines

SUMMARY

This article discusses the study of Harpaz-Rotem and associates, who examined patterns of medication use in first-diagnosed veterans with post-traumatic stress disorder (PTSD). It considers the difference between practice guidelines and actual prescribing; selectively identifies issues with antidepressants, antipsychotics, benzodiazepines and prazosin; and reviews the possible impact of new medications in the pipeline.

DECLARATION OF INTERESTS

In the past 36 months, J.D. has received compensation for consulting with Edgemont, Turing and Tonix Pharmaceuticals; royalties in connection with publications by Springer, Guilford and McFarland Publishers and use of the Connor-Davidson Resilience Scale, Davidson Trauma Scale, Social Phobia Inventory (SPIN) and Mini-SPIN; service on the INTRuST Data Safety and Monitoring Board, University of California, San Diego.

COPYRIGHT AND USAGE

© The Royal College of Psychiatrists 2016. This is an open access article distributed under the terms of the Creative Commons Non-Commercial, No Derivatives (CC BY-NC-ND) license.

Treatment-refractory posttraumatic stress disorder (TRPTSD): a review and framework for the future

Post-traumatic stress disorder (PTSD) is a serious psychiatric consequence of trauma that occurs in a proportion of individuals exposed to life-threatening events. Trauma-focused psychotherapy is often recommended as first choice for those who do not recover spontaneously. But many individuals require medications. In the US, only paroxetine (PRX) and sertraline (SRT) are FDA approved for PTSD. But response and remission rates with these medications are low, so numerous other pharmacologic interventions have been tried. To date, there has not been a systematic review of the data on what are the best next-step pharmacologic strategies for individuals who fail standard treatments. To that end, we review 168 published trials of medications other than PRX or SRT and provide a detailed analysis of the 88/168 studies that describe alternative pharmacologic interventions in patients refractory to other treatment. We also review clinical factors relevant to treatment-refractory PTSD; the neurobiology of extinction, as well as evidence-based psychotherapy and neuromodulation strategies for this condition.

PSYCHOTHERAPY VERSUS PHARMACOTHERAPY FOR POSTTRAUMATIC STRESS DISORDER: SYSTEMIC REVIEW AND META-ANALYSES TO DETERMINE FIRST-LINE TREATMENTS

BACKGROUND

Current clinical practice guidelines (CPGs) for posttraumatic stress disorder (PTSD) offer contradictory recommendations regarding use of medications or psychotherapy as first-line treatment. Direct head-to-head comparisons are lacking.

METHODS

Systemic review of Medline, EMBASE, PILOTS, Cochrane Central Register of Controlled Trials, PsycINFO, and Global Health Library was conducted without language restrictions. Randomized clinical trials ≥8 weeks in duration using structured clinical interview-based outcome measures, active-control conditions (e.g. supportive psychotherapy), and intent-to-treat analysis were selected for analyses. Independent review, data abstraction, and bias assessment were performed using standardized processes. Study outcomes were grouped around conventional follow-up time periods (3, 6, and 9 months). Combined effect sizes were computed using meta-analyses for medication versus control, medication pre-/posttreatment, psychotherapy versus control, and psychotherapy pre-/posttreatment.

RESULTS

Effect sizes for trauma-focused psychotherapies (TFPs) versus active control conditions were greater than medications versus placebo and other psychotherapies versus active controls. TFPs resulted in greater sustained benefit over time than medications. Sertraline, venlafaxine, and nefazodone outperformed other medications, although potential for methodological biases were high. Improvement following paroxetine and fluoxetine treatment was small. Venlafaxine and stress inoculation training (SIT) demonstrated large initial effects that decreased over time. Bupropion, citalopram, divalproex, mirtazapine, tiagabine, and topiramate failed to differentiate from placebo. Aripiprazole, divalproex, guanfacine, and olanzapine failed to differentiate from placebo when combined with an antidepressant.

CONCLUSIONS

Study findings support use of TFPs over nontrauma-focused psychotherapy or medication as first-line interventions. Second-line interventions include SIT, and potentially sertraline or venlafaxine, rather than entire classes of medication, such as SSRIs. Future revisions of CPGs should prioritize studies that utilize active controls over waitlist or treatment-as-usual conditions. Direct head-to-head trials of TFPs versus sertraline or venlafaxine are needed.

Initiation of pharmacotherapy for post-traumatic stress disorder among veterans from Iraq and Afghanistan: a dimensional, symptom cluster approach

BACKGROUND

The pharmacological treatment of post-traumatic stress disorder (PTSD) is extremely challenging, as no specific agent has been developed exclusively to treat this disorder. Thus, there are growing concerns among the public, providers and consumers associated with its use as the efficacy of some agents is still in question.

AIMS

We applied a dimensional and symptom cluster-based approach to better understand how the heterogeneous phenotypic presentation of PTSD may relate to the initiation of pharmacotherapy for PTSD initial episode.

METHOD

US veterans who served in the conflicts in Iraq and Afghanistan and received an initial PTSD diagnosis at the US Veterans Health Administration between 2008 and 2011 were included in this study. Veterans were followed for 365 days from initial PTSD diagnosis to identify initiation for antidepressants, anxiolytics/sedatives/hypnotics, antipsychotics and prazosin. Multivariable analyses were used to assess the relationship between the severity of unique PTSD symptom clusters and receiving prescriptions from each medication class, as well as the time from diagnosis to first prescription.

RESULTS

Increased severity of emotional numbing symptoms was independently associated with the prescription of antidepressants, and they were prescribed after a substantially shorter period of time than other medications. Anxiolytics/sedatives/hypnotics prescription was associated with heightened re-experiencing symptoms and sleep difficulties. Antipsychotics were associated with elevated re-experiencing and numbing symptoms and prazosin with reported nightmares.

CONCLUSIONS

Prescribing practices for military-related PTSD appear to follow US VA/DoD clinical guidelines. Results of this study suggest that a novel dimensional and symptom cluster-based approach to classifying the phenotypic presentation of military-related PTSD symptoms may help inform prescribing patterns for PTSD.

DECLARATION OF INTEREST

None.

COPYRIGHT AND USAGE

© The Royal College of Psychiatrists 2016. This is an open access article distributed under the terms of the Creative Commons Non-Commercial, No Derivatives (CC BY-NC-ND) license.

The epidemiology of DSM-5 posttraumatic stress disorder in the United States: results from the National Epidemiologic Survey on Alcohol and Related Conditions-III

OBJECTIVES

To present current, nationally representative US findings on the past-year and lifetime prevalences, sociodemographic correlates, psychiatric comorbidity, associated disability, and treatment of DSM-5 posttraumatic stress disorder (PTSD).

METHODS

Face-to-face interviews with 36,309 adults in the 2012-2013 National Epidemiologic Survey on Alcohol and Related Conditions-III. PTSD, alcohol and drug use disorders, and selected mood, anxiety, and personality disorders were assessed using the Alcohol Use Disorder and Associated Disabilities Interview Schedule-5.

RESULTS

Past-year and lifetime prevalences were 4.7 and 6.1 %, higher for female, white, Native American, younger, and previously married respondents, those with <high school education and lower incomes, and rural residents. PTSD was significantly associated with a broad range of substance use, mood, anxiety, and personality disorders, and past-month disability. Among respondents with lifetime PTSD, 59.4 % sought treatment; an average of 4.5 years elapsed from disorder onset to first treatment.

CONCLUSIONS

DSM-5 PTSD is prevalent, highly comorbid, disabling, and associated with delayed help seeking. Additional research is needed to elucidate relationships identified herein, estimate PTSD-related costs, investigate hypotheses regarding etiology, course, and treatment, and support decisions about resource allocation to service delivery and research. Initiatives are needed to destigmatize PTSD, educate the public about its treatment, and encourage affected individuals to seek help.

Treatment Options for Individuals with PTSD and Concurrent TBI: A Literature Review and Case Presentation

Posttraumatic stress disorder (PTSD) is a well-studied mental health condition with existing guidelines and algorithms for treatment of PTSD. Those guidelines, while acknowledging an increased complexity, fail to provide clear PTSD treatment guidelines when an individual has a concurrent traumatic brain injury (TBI) diagnosis. Therefore, a literature review along with an accompanying case presentation is presented to demonstrate the minimum necessary considerations for approaching treatment of this complex population. Treatment approaches must be lead by providers that have the expertise and training necessary to consider all facets of the patient and their potential options. The provider must consider the pathophysiology of PTSD and TBI and be capable of leading a team to identify the patient's source(s) of dysfunction, current cognitive abilities, and potential indications for psychotropic medications and/or other types of therapeutic intervention.

Influence of baseline severity on antidepressant efficacy for anxiety disorders: meta-analysis and meta-regression

BACKGROUND

Antidepressants are established first-line treatments for anxiety disorders, but it is not clear whether they are equally effective across the severity range.

AIMS

To examine the influence of baseline severity of anxiety on antidepressant efficacy for generalised anxiety disorder (GAD), social anxiety disorder (SAD), obsessive-compulsive disorder (OCD), post-traumatic stress disorder (PTSD) and panic disorder.

METHOD

Fifty-six trials of second-generation antidepressants for the short-term treatment of an anxiety disorder were included. Baseline and change scores were extracted for placebo and treatment groups in each trial. Mixed effects meta-regression was used to investigate the effects of treatment group, baseline severity and their interaction.

RESULTS

Increased baseline severity did not predict greater improvement in drug groups compared with placebo groups. Standardised regression coefficients of the interaction term between baseline severity and treatment group were 0.04 (95% CI -0.13 to 0.20, P = 0.65) for GAD, -0.06 (95% CI -0.20 to 0.09, P = 0.43) for SAD, 0.04 (95% CI -0.07 to 0.16, P = 0.46) for OCD, 0.16 (95% CI -0.22 to 0.53, P = 0.37) for PTSD and 0.002 (95% CI -0.10 to 0.10, P = 0.96) for panic disorder. For OCD, baseline severity did predict improvement in both placebo and drug groups equally (β = 0.11, 95% CI 0.05 to 0.17, P = 0.001).

CONCLUSIONS

No relationship between baseline severity and drug-placebo difference was found for anxiety disorders. These results suggest that if the efficacy of antidepressants is considered clinically relevant, they may be prescribed to patients with anxiety regardless of symptom severity.

Caring for Trauma Survivors

Although trauma exposure is common, few people develop acute and chronic psychiatric disorders. Those who develop posttraumatic stress disorder likely have coexisting psychiatric and physical disorders. Psychiatric nurses must be knowledgeable about trauma responses, implement evidence-based approaches to conduct assessments, and create safe environments for patients. Most researchers assert that trauma-focused cognitive-behavioral approaches demonstrate the most efficacious treatment outcomes. Integrated approaches, offer promising treatment options. This article provides an overview of clinical factors necessary to help the trauma survivor begin the process of healing and recovery and attain an optimal level of functioning.

Noradrenergic dysregulation in the pathophysiology of PTSD

A central role for noradrenergic dysregulation in the pathophysiology of post-traumatic stress disorder (PTSD) is increasingly suggested by both clinical and basic neuroscience research. Here, we integrate recent findings from clinical and animal research with the earlier literature. We first review the evidence for net upregulation of the noradrenergic system and its responsivity to stress in individuals with PTSD. Next, we trace the evidence that the α₁ noradrenergic receptor antagonist prazosin decreases many of the symptoms of PTSD from initial clinical observations, to case series, to randomized controlled trials. Finally, we review the basic science work that has begun to explain the mechanism for this efficacy, as well as to explore its possible limitations and areas for further advancement. We suggest a view of the noradrenergic system as a central, modifiable link in a network of interconnected stress-response systems, which also includes the amygdala and its modulation by medial prefrontal cortex. Particular attention is paid to the evidence for bidirectional signaling between noradrenaline and corticotropin-releasing factor (CRF) in coordinating these interconnected systems. The multiple different ways in which the sensitivity and reactivity of the noradrenergic system may be altered in PTSD are highlighted, as is the evidence for possible heterogeneity in the pathophysiology of PTSD between different individuals who appear clinically similar. We conclude by noting the importance moving forward of improved measures of noradrenergic functioning in clinical populations, which will allow better recognition of clinical heterogeneity and further assessment of the functional implications of different aspects of noradrenergic dysregulation.

Pharmacotherapies for Posttraumatic Stress Disorder: A Meta-Analysis

The purpose of this study was to assess the acceptability and efficacy of all types of pharmacotherapeutic agents in reducing the symptoms of posttraumatic stress disorder (PTSD). In this systematic meta-analysis, the dropout and response rates of various pharmacotherapy and placebo treatments reported by randomized clinical trials were compared. A total of 34 reports that described the acceptability and efficacy of PTSD pharmacotherapies were retrieved and analyzed. Of them, 30 trials examined the dropout rate as an index of acceptability and revealed the superiority of the PTSD pharmacotherapy to placebos (odds ratio, 0.75; 95% confidence interval, 0.66-0.86; n = 4313). The response rate was determined in 20 trials as an index of efficacy, showing that the PTSD pharmacotherapies were superior to the placebos (odds ratio, 1.47; 95% confidence interval, 1.34-1.62; n = 2166). Pharmacotherapy is an important component of the care of patients with PTSD.

Comorbidity between post-traumatic stress disorder and major depressive disorder: alternative explanations and treatment considerations

Approximately half of people with post-traumatic stress disorder (PTSD) also suffer from Major Depressive Disorder (MDD). The current paper examines evidence for two explanations of this comorbidity. First, that the comorbidity reflects overlapping symptoms in the two disorders. Second, that the co-occurrence of PTSD and MDD is not an artifact, but represents a trauma-related phenotype, possibly a subtype of PTSD. Support for the latter explanation is inferred from literature that examines risk and biological correlates of PTSD and MDD, including molecular processes. Treatment implications of the comorbidity are considered.

SiRNA-mediated serotonin transporter knockdown in the dorsal raphe nucleus rescues single prolonged stress-induced hippocampal autophagy in rats

The neurobiological mechanisms underlying the development of post-traumatic stress disorder (PTSD) remain elusive. One of the hypotheses is the dysfunction of serotonin (5-HT) neurotransmission, which is critically regulated by serotonin transporter (SERT). Therefore, we hypothesized that attenuation of SERT gene expression in the hippocampus could prevent hippocampal autophagy and the development of PTSD-like behavior. To this end, we infused SLC6A4 siRNAs into the dorsal raphe nucleus (DRN) to knockdown SERT gene expression after a single prolonged stress (SPS) treatment in rats. Then, we evaluated the effects of SERT gene knockdown on anxiety-related behaviors and extinction of contextual fear memory. We also examined the histological changes and the expression of Beclin-1, LC3-I, and LC3-II in the hippocampus. We found that SPS treatment did not alter anxiety-related behaviors but prolonged the extinction of contextual fear memory, and such a behavioral phenomenon was correlated with increased hippocampal autophagy, decreased 5-HT level, and increased expression of Beclin-1 and LC3-II/LC3-I ratio in the hippocampus. Furthermore, intra-DRN infusion of SLC6A4 siRNAs promoted the extinction of contextual fear memory, prevented hippocampal autophagy, increased 5-HT level, and decreased expression of Beclin-1 and LC3-II/LC3-I ratio. These results indicated that SERT may play a critical role in the pathogenesis of hippocampal autophagy, and is likely involved in the development of PTSD.

Effects of extinction treatments on the reduction of conditioned responding and conditioned hyperarousal in a rabbit model of posttraumatic stress disorder (PTSD)

We have previously characterized a model of posttraumatic stress disorder (PTSD), based on classical conditioning of the rabbit nictitating membrane response (NMR), that focuses on 2 key PTSD-like features: conditioned responses to trauma-associated cues and hyperarousal. In addition to the development of conditioned NMRs (CRs) to a tone conditioned stimulus (CS) associated with a periorbital shock unconditioned stimulus (US), we have observed that rabbits also exhibit a conditioning-specific reflex modification (CRM) of the NMR that manifests as an exaggerated and more complex reflexive NMR to presentations of the US by itself, particularly to intensities that elicited little response prior to conditioning. Previous work has demonstrated that unpaired presentations of the CS and US are successful at extinguishing CRs and CRM simultaneously, even when a significantly weakened version of the US is utilized. In the current study, additional extinction treatments were tested, including continued pairings of the CS with a weakened US and exposure to the training context alone, and these treatments were contrasted with the effects of unpaired extinction with a weakened US and remaining in home cages with no further treatment. Results showed that continued pairings only slightly decreased CRs and CRM, while context exposure had no effect on CRs and marginal effects on reducing CRM. Unpaired extinction was still the most effective treatment for reducing both. Findings are discussed in terms of applications to cognitive-behavioral therapies for treatment of PTSD, such as incorporating mild, innately stressful stimuli into virtual reality therapy.

Alpha-2 receptor agonists for the treatment of posttraumatic stress disorder

Clonidine and guanfacine are alpha-2 receptor agonists that decrease sympathetic outflow from the central nervous system. Posttraumatic stress disorder (PTSD) is an anxiety disorder that is theorized to be related to a hyperactive sympathetic nervous system. Currently, the only US Food and Drug Administration (FDA)-approved medications for PTSD are the selective serotonin reuptake inhibitors (SSRIs) sertraline and paroxetine. Sometimes use of the SSRIs may not lead to full remission and symptoms of hyperarousal often persist. This article specifically reviews the literature on alpha-2 receptor agonist use for the treatment of PTSD and concludes that while the evidence base is limited, these agents might be considered useful when SSRIs fail to treat symptoms of agitation and hyperarousal in patients with PTSD.