Placebo effects in randomized trials of pharmacological and neurostimulation interventions for mental disorders: An umbrella review.

There is a growing literature exploring the placebo response within specific mental disorders, but no overarching quantitative synthesis of this research has analyzed evidence across mental disorders. We carried out an umbrella review of meta-analyses of randomized controlled trials (RCTs) of biological treatments (pharmacotherapy or neurostimulation) for mental disorders. We explored whether placebo effect size differs across distinct disorders, and the correlates of increased placebo effects. Based on a pre-registered protocol, we searched Medline, PsycInfo, EMBASE, and Web of Knowledge up to 23.10.2022 for systematic reviews and/or meta-analyses reporting placebo effect sizes in psychopharmacological or neurostimulation RCTs. Twenty meta-analyses, summarising 1,691 RCTs involving 261,730 patients, were included. Placebo effect size varied, and was large in alcohol use disorder (g = 0.90, 95% CI [0.70, 1.09]), depression (g = 1.10, 95% CI [1.06, 1.15]), restless legs syndrome (g = 1.41, 95% CI [1.25, 1.56]), and generalized anxiety disorder (d = 1.85, 95% CI [1.61, 2.09]). Placebo effect size was small-to-medium in obsessive-compulsive disorder (d = 0.32, 95% CI [0.22, 0.41]), primary insomnia (g = 0.35, 95% CI [0.28, 0.42]), and schizophrenia spectrum disorders (standardized mean change = 0.33, 95% CI [0.22, 0.44]). Correlates of larger placebo response in multiple mental disorders included later publication year (opposite finding for ADHD), younger age, more trial sites, larger sample size, increased baseline severity, and larger active treatment effect size. Most (18 of 20) meta-analyses were judged 'low' quality as per AMSTAR-2. Placebo effect sizes varied substantially across mental disorders. Future research should explore the sources of this variation. We identified important gaps in the literature, with no eligible systematic reviews/meta-analyses of placebo response in stress-related disorders, eating disorders, behavioural addictions, or bipolar mania.

Placebo Effects Are Small on Average in the 7.5% CO2 Inhalational Model of Generalized Anxiety.

BACKGROUND: Anxiety disorders are highly prevalent and socio-economically costly. Novel pharmacological treatments for these disorders are needed because many patients do not respond to current agents or experience unwanted side effects. However, a barrier to treatment development is the variable and large placebo response rate seen in trials of novel anxiolytics. Despite this, the mechanisms that drive placebo responses in anxiety disorders have been little investigated, possibly due to low availability of convenient experimental paradigms. We aimed to develop and test a novel protocol for inducing placebo anxiolysis in the 7.5% CO2 inhalational model of generalized anxiety in healthy volunteers. METHODS: Following a baseline 20-minute CO2 challenge, 32 healthy volunteers were administered a placebo intranasal spray labelled as either the anxiolytic "lorazepam" or "saline." Following this, participants surreptitiously underwent a 20-minute inhalation of normal air. Post-conditioning, a second dose of the placebo was administered, after which participants completed another CO2 challenge. RESULTS: Participants administered sham "lorazepam" reported significant positive expectations of reduced anxiety (P = .001), but there was no group-level placebo effect on anxiety following CO2 challenge post-conditioning (Ps > .350). Surprisingly, we found many participants exhibited unexpected worsening of anxiety, despite positive expectations. CONCLUSIONS: Contrary to our hypothesis, our novel paradigm did not induce a placebo response, on average. It is possible that effects of 7.5% CO2 inhalation on prefrontal cortex function or behavior in line with a Bayesian predictive coding framework attenuated the effect of expectations on subsequent placebo response. Future studies are needed to explore these possibilities.

Validity of root cause analysis in investigating adverse events in psychiatry.

Root cause analysis (RCA), imported from high-reliability industries into health two decades ago, is the mandated methodology to investigate adverse events in most health systems. In this analysis, we argue that the validity of RCA in health and in psychiatry must be established, given the impact of these investigations on mental health policy and practice.

Latency to selective serotonin reuptake inhibitor vs benzodiazepine treatment in patients with panic disorder: a naturalistic study.

BACKGROUND: Panic disorder (PD) is a prevalent and impairing anxiety disorder with previous reports suggesting that the longer the condition remains untreated, the greater the likelihood of nonresponse. However, patients with PD may wait for years before receiving a guideline-recommended pharmacological treatment. The widespread prescription of benzodiazepines (BDZ) for managing anxiety symptoms and disorders might delay the administration of pharmacotherapy according to guidelines (eg, selective serotonin reuptake inhibitors, SSRIs). The present study aimed to determine the mean duration of untreated illness (DUI) in a sample of PD patients, to quantify and compare DUI-SSRI to DUI-BDZ, and to compare findings with those from previous investigations. METHODS: Three hundred and fourteen patients with a Diagnostic and Statistical Manual of Mental Disorders, fifth edition diagnosis of PD were recruited from an Italian outpatient psychotherapy unit, and epidemiological and clinical variables were retrieved from medical records. Descriptive statistical analyses were undertaken for sociodemographic and clinical variables, Wilcoxon matched-pair signed rank test was applied to compare the distribution of DUI-SSRI vs DUI-BDZ, and Welch's t test was performed to compare findings with those from previous studies. RESULTS: The mean DUI-SSRI of the total sample was 64.25 ± 112.74 months, while the mean DUI-BDZ was significantly shorter (35.09 ± 78.62 months; P < 0.0001). A significantly longer DUI-SSRI, compared to findings from previous studies, was also observed. CONCLUSIONS: The present results confirm a substantial delay in implementing adequate pharmacological treatments in patients with PD, and highlight the discrepancy between recommendations from international treatment guidelines and common clinical practice in relation to BDZ prescription.

Selective serotonin reuptake inhibitors, post-treatment sexual dysfunction and persistent genital arousal disorder: A systematic review.

PURPOSE: Adverse effects of selective serotonin reuptake inhibitors (SSRIs) on sexual function have been an important area of research for many years. However, the duration of SSRI-associated sexual adverse effects, and their possible persistence after treatment discontinuation, is still uncertain. The aims of the current systematic review were first to identify existing evidence of sexual dysfunction following SSRI discontinuation, and to provide an account of reported symptoms and proposed treatment options; and second, to establish whether current literature allows accurate estimates of the prevalence of such sexual dysfunction. METHODS: A systematic review was conducted on PubMed, Embase, and Google Scholar; papers with clinical data regarding patients with persistent sexual dysfunction after SSRI treatment suspension were included. RESULTS: Overall, two retrospective interventional studies, six observational studies and 11 case reports were judged eligible for inclusion. It was not possible to determine reliable estimates of prevalence. Similarly, a cause-effect relationship between SSRI exposure and persistent sexual impairment could not be ascertained. Nonetheless, the potential for continued sexual disturbances despite discontinuation could not be entirely ruled out. CONCLUSIONS: There is a need to investigate a possible dose-response relationship between SSRI exposure and persistent sexual adverse effects. Treatment options for persistent dysfunctions remain limited, but novel therapeutic approaches may be required in order to address an otherwise neglected need for sexual well-being.

Feasibility, acceptability and practicality of transcranial stimulation in obsessive compulsive symptoms (FEATSOCS): A randomised controlled crossover trial.

BACKGROUND: Transcranial direct current stimulation (tDCS) is a non-invasive form of neurostimulation with potential for development as a self-administered intervention. It has shown promise as a safe and effective treatment for obsessive compulsive disorder (OCD) in a small number of studies. The two most favourable stimulation targets appear to be the left orbitofrontal cortex (L-OFC) and the supplementary motor area (SMA). We report the first study to test these targets head-to-head within a randomised sham-controlled trial. Our aim was to inform the design of future clinical research studies, by focussing on the acceptability and safety of the intervention, feasibility of recruitment, adherence to and tolerability of tDCS, and the size of any treatment-effect. METHODS: FEATSOCS was a randomised, double-blind, sham-controlled, cross-over, multicentre study. Twenty adults with DSM-5-defined OCD were randomised to treatment, comprising three courses of clinic-based tDCS (SMA, L-OFC, Sham), randomly allocated and delivered in counterbalanced order. Each course comprised four 20-min 2 mA stimulations, delivered over two consecutive days, separated by a 'washout' period of at least four weeks. Assessments were carried out by raters who were blind to stimulation-type. Clinical outcomes were assessed before, during, and up to four weeks after stimulation. Patient representatives with lived experience of OCD were actively involved at all stages. RESULTS: Clinicians showed willingness to recruit participants and recruitment to target was achieved. Adherence to treatment and study interventions was generally good, with only two dropouts. There were no serious adverse events, and adverse effects which did occur were transient and mostly mild in intensity. Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) scores were numerically improved from baseline to 24 h after the final stimulation across all intervention groups but tended to worsen thereafter. The greatest effect size was seen in the L-OFC arm, (Cohen's d = -0.5 [95% CI -1.2 to 0.2] versus Sham), suggesting this stimulation site should be pursued in further studies. Additional significant sham referenced improvements in secondary outcomes occurred in the L-OFC arm, and to a lesser extent with SMA stimulation. CONCLUSIONS: tDCS was acceptable, practicable to apply, well-tolerated and appears a promising potential treatment for OCD. The L-OFC represents the most promising target based on clinical changes, though the effects on OCD symptoms were not statistically significant compared to sham. SMA stimulation showed lesser signs of promise. Further investigation of tDCS in OCD is warranted, to determine the optimal stimulation protocol (current, frequency, duration), longer-term effectiveness and brain-based mechanisms of effect. If efficacy is substantiated, consideration of home-based approaches represents a rational next step. TRIAL REGISTRATION: ISRCTN17937049. https://doi.org/10.1186/ISRCTN17937049.

Apathy associated with antidepressant drugs: a systematic review.

OBJECTIVES: Administration of antidepressant drugs - principally selective serotonin reuptake inhibitors (SSRIs) - may induce clinically significant 'apathy' which can affect treatment outcomes adversely. We aimed to review all relevant previous reports. METHODS: We performed a PUBMED search of English-language studies, combining terms concerning psychopathology (e.g. apathy) and classes of antidepressants (e.g. SSRI). RESULTS: According to certain inclusion (e.g. use of DSM/ICD diagnostic criteria) and exclusion (e.g. presence of a clinical condition that may induce apathy) criteria, 50 articles were eligible for review. Together, they suggest that administration of antidepressants - usually SSRIs - can induce an apathy syndrome or emotional blunting, i.e. a decrease in emotional responsiveness, to circumstances which would have triggered intense mood reactions prior to pharmacotherapy. The reported prevalence of antidepressant-induced apathy ranges between 5.8 and 50%, and for SSRIs ranges between 20 and 92%. Antidepressant-induced apathy emerges independently of diagnosis, age, and treatment outcome and appears dose-dependent and reversible. The main treatment strategy is dose reduction, though some data suggest the usefulness of treatment with olanzapine, bupropion, agomelatine or amisulpride, or the methylphenidate-modafinil-olanzapine combination. CONCLUSION: Antidepressant-induced apathy needs careful clinical attention. Further systematic research is needed to investigate the prevalence, course, aetiology, and treatment of this important clinical condition.

Effects of exercise on obsessive-compulsive disorder symptoms: a systematic review and meta-analysis.

OBJECTIVE: This systematic review and meta-analysis assessed the efficacy of exercise in reducing OCD symptoms. METHODS: We searched PubMed, Cochrane Central Register of Controlled Trials, MEDLINE, Scopus and grey literature until March 2022. The study was preregistered at Prospero (CRD42021283931). We included randomised controlled and pre-post trials assessing physical activity as an intervention for OCD. Risk of bias was assessed using the Cochrane ROBINS-I tool and the RoB2 tool. RESULTS: The analysis included 6 trials (N = 92); 2 were RCTS and 4 were pre-post design studies. A random-effects meta-analysis of pre-post data identified a large reduction of OCD symptoms following exercise (g = 1.33 [95%CI 1.06-1.61]; k = 6). Exercise was also associated with significant pre-post reductions in anxiety (g = 0.71 [95%CI 0.37-1.05; k = 4) and depression (g = 0.57 [95%CI 0.26-0.89]; k = 2). Risk of bias was moderate-high in uncontrolled trials on the ROBINS-I and RCTs showed 'some concerns' on the RoB2. CONCLUSION: Exercise was associated with a large pre-post reduction of OCD symptoms; however, few trials were of robust quality and all were at risk of bias. Further well-powered and better quality RCTs are required to assess the role of exercise as an intervention for OCD.KEY POINTSStudies exploring exercise as an adjunct therapy for OCD have small participant numbers, therefore a systematic review and meta-analysis is needed to estimate potential efficacy.Pre-post analysis shows that exercise was associated with a large reduction of OCD symptomsThe current systematic review and meta-analysis points to the potential for exercise to be beneficial for the treatment for OCD symptoms. However, more well-powered and better controlled RCTs are required to fully assess the benefit of exercise for the treatment of OCD symptoms.

Functional Neuroimaging Correlates of Placebo Response in Patients With Depressive or Anxiety Disorders: A Systematic Review.

BACKGROUND: The mechanisms underlying placebo effects of psychotropic drugs remain poorly understood. We carried out the first, to our knowledge, systematic review of functional neuroimaging correlates of placebo response in adults with anxiety/depressive disorders. METHODS: We systematically searched a large set of databases up to February 2021 based on a pre-registered protocol (PROSPERO CRD42019156911). We extracted neuroimaging data related to clinical improvement following placebo or related to placebo mechanisms. We did not perform a meta-analysis due to the small number of included studies and significant heterogeneity in study design and outcome measures. RESULTS: We found 12 relevant studies for depressive disorders and 4 for anxiety disorders. Activity in the ventral striatum, rostral anterior cingulate cortex and other default mode network regions, orbitofrontal cortex, and dorsolateral prefrontal cortex correlated with placebo antidepressant responses. Activity in regions of the default mode network, including posterior cingulate cortex, was associated with placebo anxiolysis. There was also evidence for possible involvement of the endogenous opioid, dopamine, and serotonin systems in placebo antidepressant and anxiolytic effects. CONCLUSIONS: Several brain regions and molecular systems may be involved in these placebo effects. Further adequately powered studies exploring causality and controlling for confounders are required.

Relationship of behavioral inhibition to separation anxiety in a sample (N = 377) of adult individuals with mood and anxiety disorders.

BACKGROUND: Behavioral Inhibition (BI) is an early temperamental trait characterized by shyness, withdrawal, avoidance, uneasiness, and fear of unfamiliar situations, people, objects, and events. The DSM-5 refers to behavioral inhibition as a temperamental factor related to neurodevelopmental conditions in childhood, including attention deficit hyperactivity disorder, selective mutism, and specific phobias; and to its influence on adult anxiety disorders including social anxiety disorder, agoraphobia, and generalized anxiety disorder, but, interestingly, not separation anxiety disorder (SAD). However, there are phenomenological overlaps between BI and SAD. We aimed to explore whether there is a correlation between BI as an early temperamental trait and childhood or adult separation anxiety disorder. METHODS: The study was conducted in 377 consecutive adults (mean age 40.2±12.4 years) outpatients with anxiety and mood disorders as the principal diagnosis, grouped on the presence/absence of a DSM-5 diagnosis of childhood or adult separation anxiety disorder. Separation anxiety was assessed by the Structured Clinical Interview for Separation Anxiety (SCI-SAS) and the Adult Separation Anxiety Checklist (ASA27). Behavioral inhibition was assessed by the Retrospective Self-Report of Inhibition (RSRI). RESULTS: The four comparison groups included: 1) 168 patients without childhood or adult SAD, 2) 81 with adult SAD, 3) 97 with both adult SAD and childhood SAD, and 4) 31 with childhood SAD only. The group with both adult and childhood SAD had the highest scores on RSRI total and sub-scale scores. Both groups with adult SAD had significantly higher RSRI scores than the group with only childhood SAD or without SAD. Significant bivariate correlations were found between ASA-27 scores and RSRI scores. Correlations between RSRI scores and measures of anxiety and depressive symptoms were significantly weaker than those on the ASA-27. Regression analyses showed a significant predictive value of RSRI scores on ASA-27 total score, but not of age of onset of SAD. CONCLUSIONS: BI has an onset in the very first years of life and may represent a potential developmental endophenotype for later anxiety disorders. Our findings indicate that BI and separation anxiety are connected in individuals with affective and anxiety disorders. This may have important clinical and therapeutic implications for preventive interventions.

Anxiety in asthma: a systematic review and meta-analysis.

BACKGROUND: Background: Growing evidence from observational studies indicates a high prevalence of anxiety in asthma. However, prevalence rates of coexisting anxiety symptoms and comorbid anxiety disorders vary widely across studies. We aimed to evaluate the associations between anxiety and asthma and provide more precise comorbidity estimates. METHODS: We systematically reviewed the literature from case-controlled studies and conducted a meta-analysis to evaluate the pooled prevalence estimates and risks of anxiety symptoms and anxiety disorders in asthma individuals. Screening, data extraction, and quality assessment were undertaken following PRISMA guidelines for preferred reporting of systematic reviews and meta-analysis. A random-effects model was used to calculate pooled prevalence rates. Meta-analysis was conducted using Review Manager 5.3. Multiple databases including PubMed, ScienceDirect, PsychINFO, and PsycARTICLES were searched for publications before 1 December 2019. The review protocol was registered on PROSPERO (ref: CRD42020176028). RESULTS: In total, 19 studies involving 106813 participants were included. The pooled prevalence of anxiety symptoms and anxiety disorders in individuals with asthma was 0.32 (95% CI 0.22-0.43) and 0.24 (95% CI 0.13-0.41), respectively. The risks of coexisting anxiety symptoms and comorbid anxiety disorders were significantly higher in asthma patients than in non-asthma controls indicated by OR 1.89 (95% CI 1.42-2.52; Z = 4.37; p < 0.001) and OR 2.08 (95% CI 1.70-2.56; Z = 6.97; p < 0.001), respectively. Anxiety symptoms and anxiety disorders occur at increased frequency among patients with asthma. CONCLUSIONS: Our findings highlight the need for appropriate assessments for these comorbid conditions, which may help to identify a subgroup of patients who might benefit from interventions designed to reduce anxiety and enhance the quality of life.

Time to Reconsider Monoamine Oxidase Inhibitors for Obsessive Compulsive Disorder?: A Case Series Using Phenelzine.

PURPOSE/BACKGROUND: Despite the availability of a range of efficacious evidence-based treatments for obsessive-compulsive disorder (OCD), not all patients experience sufficient benefit or are able to tolerate them in practice. Monoamine oxidase inhibitors (MAOIs) show efficacy in the treatment of depression and certain anxiety disorders (such as social anxiety disorder). METHODS/PROCEDURES: We survey the evidence base from case reports, and clinical trials, regarding use of MAOIs in OCD. We then present new data from a case series collected in routine clinical practice in a specialist clinical service. FINDINGS/RESULTS: In 9 treatment-resistant patients whose OCD had not improved with at least 2 standard treatment trials, 3 had marked clinical improvement (>35% improvement on YBOCS) on phenelzine, 3 had some improvement (15-34.9%), and 3 showed minimal or no improvement (<15%). In the 3 patients who experienced minimal/no improvement, 2 had discontinued early because of lack of tolerability, and the other patient discontinued after 4 weeks because of perceived lack of symptom benefit. IMPLICATIONS/CONCLUSIONS: We suggest that (1) MAOIs in treatment-resistant OCD require appropriate research scrutiny in large-scale randomized controlled trials; and (2) MAOIs merit consideration as a treatment option in individual cases of OCD, particularly in specialist settings where first-line interventions have proven inadequate to manage severe symptoms.

Patient experience of lasting negative effects of psychological interventions for anxiety and depression in secondary mental health care services: a national cross-sectional study.

BACKGROUND: Patients who undergo psychological treatment can report both negative and positive effects, but evidence of factors influencing the likelihood of negative effects is limited. AIMS: To identify aspects of the organisation and delivery of secondary care psychological treatment services that are associated with patient experiences of negative effects. METHOD: Cross-sectional survey of people with anxiety and depression who ended psychological treatment delivered by 50 NHS trusts in England. Respondents were asked about how their treatment was organised and delivered and whether they experienced lasting negative effects. RESULTS: Of 662 respondents, 90 (14.1%) reported experiencing lasting negative effects. People over the age of 65 were less likely than younger respondents to report negative effects. There was an association between reporting neutral or negative effects and not being referred at what respondents considered to be the right time (OR = 1.712, 95% CI = 1.078-2.726), not receiving the right number of sessions (OR = 3.105, 95% CI = 1.934-4.987), and not discussing progress with their therapist (OR 2.063, 95% CI = 1.290-3.301). CONCLUSIONS: One in seven patients who took part in this survey reported lasting negative effects from psychological treatment. Steps should be taken to prepare people for the potential for negative experiences of treatment, and progress reviewed during therapy in an effort to identify and prevent negative effects.

Impact of Substance Use Disorder on Quality of Inpatient Mental Health Services for People With Anxiety and Depression.

Objective: Substance use disorders are commonly comorbid with anxiety and depressive disorders and are associated with poor treatment outcomes. The mechanisms underlying this association remain unclear-one possibility is that patients with anxiety/depressive disorders and substance use disorders receive poorer treatment. Concerns have been raised about the quality of inpatient care received by patients with substance use disorders. The purspose of this research was to examine the quality of care received by inpatients with an anxiety or depressive disorder, comparing subgroups with or without a comorbid substance use disorder. Methods: This was a retrospective case-note review of 3,795 patients admitted to inpatient psychiatric wards in England. Data were gathered on all acute admissions with anxiety/depressive illness over a 6-month period, for a number of measures of quality of care derived from national standards. Association of coexisting substance use disorders with a variety of quality of care outcomes (relating to assessment, care planning, medication management, psychological therapies, discharge, crisis planning, and follow-up) was investigated using multivariable regression analyses. Results: In all, 543 (14.3%) patients in the study had a secondary diagnosis of a substance use disorder. Patients with substance use disorders were less likely to have had care plans that were developed jointly (i.e., with input from both patient and clinician; odds ratio [OR] = 0.76, 95% confidence interval [CI] [0.55, 0.93], p = .034) and less likely to have had their medication reviewed either during the admission (OR = 0.83, 95% CI [0.69, 0.94], p = .030) or at follow-up after discharge (OR = 0.58, 95% CI [0.39, 0.86], p = .007). Carers of patients with substance use disorders were less likely to have been provided with information about available support services (OR = 0.79, 95% CI [0.57, 0.98], p = .047). Patients with substance use disorders were less likely to have received adequate (at least 24 hours) notice in advance of their discharge (OR = 0.72, 95% CI [0.54, 0.96], p = .033), as were their carers (OR = 0.63, 95% CI [0.41, 0.85], p = .007). They were less likely to have a crisis plan in place at the point of discharge (OR = 0.85, 95% CI [0.74, 0.98], p = .044). There was also strong evidence that patients with substance use disorders were less likely to have been referred for psychological therapy (OR = 0.69, 95% CI [0.55, 0.87], p = .002). Conclusions: We found evidence of poorer quality of care for inpatients with anxiety and depressive disorders with comorbid substance use disorders, highlighting the need for more to be done to support these patients. Discrepancies in care quality may be contributed to the poor treatment outcomes experienced by patients with substance use disorders, and strategies to reduce this inequality are necessary to improve the well-being of this substantial patient group.

Hair cortisol concentration in anxiety disorders: exploration of relationships with symptom severity and inflammatory markers.

BACKGROUND: Hair cortisol concentration (HCC) can be used to periodically assess hypothalamic-pituitary-adrenal (HPA) axis function, and appears correlated with prolonged exposure to stress. METHODS: Serial assessment (at Baseline, Week 6 and Week 12) of participants (n = 35) with anxiety disorders by psychopathological rating scales, with assays of HCC and levels of peripheral anti- and pro-inflammatory cytokines. Patients underwent antidepressant treatment for an initial 6 weeks, followed by cyclo-oxygenase inhibitor-2 (COX-2) inhibitor (celecoxib) augmentation or 'treatment as usual' for a further 6 weeks. RESULTS: At Baseline (n = 35), HCC was elevated in patients with single-episode but not recurrent-episode anxiety disorders, mean IL-12p70 levels were low, and mean TNF-α levels were elevated. Following 6 weeks of antidepressant treatment (n = 33), mean HCC was within the normal range but mean IL-2 level was low. Celecoxib augmentation (n = 18) was associated with a reduction in anxiety symptoms and normalisation of mean IL-2 levels. LIMITATIONS: Small sample size. Not all participants were assessed at all time points. CONCLUSION: Serial assessment of HCC is practicable in patients with anxiety disorders. These preliminary findings warrant further investigation in larger samples.

Brain Functional Connectivity Correlates of Response in the 7.5% CO2 Inhalational Model of Generalized Anxiety Disorder: A Pilot Study.

BACKGROUND: The 7.5% CO2 inhalational model can be used to explore potential treatments for generalized anxiety disorder. However, it is unknown how inter-individual variability in the functional architecture of negative affective valence systems might relate to anxiogenic response in this model. METHODS: A total of 13 healthy volunteers underwent functional magnetic resonance imaging during a passive emotional face perception task. We explored task-evoked functional connectivity in the potential threat system through generalized psychophysiological interaction analysis. Within 7 days, these participants underwent prolonged 7.5% CO2 inhalation, and results from the generalized psychophysiological interaction analysis were correlated with CO2 outcome measures. RESULTS: Functional connectivity between ventromedial prefrontal cortex and right amygdala positively correlated with heart rate and subjective anxiety, while connectivity between midcingulate cortex and left amygdala negatively correlated with anxiety during CO2 challenge. CONCLUSIONS: Response to CO2 challenge correlated with task-evoked functional connectivity in the potential threat system. Further studies should assess whether this translates into clinical populations.

Why we need more research into the placebo response in psychiatry.

Placebos are not inert, but exert measurable biological effects. The placebo response in psychiatric illness is important and clinically relevant, but remains poorly understood. In this paper, we review current knowledge about the placebo response in psychiatric medicine and identify research directions for the future. We argue that more research is needed into the placebo response in psychiatric medicine for three broad reasons. First, awareness of factors that cause placebo response, for whom, and when, within clinical trials will allow us to better evidence efficacy of new treatments. Second, by understanding how placebo mechanisms operate in the clinic, we can take advantage of these to optimise the effects of current treatments. Finally, exploring the biological mechanisms of placebo effects might reveal tractable targets for novel treatment development.

Structured review of the use of the Arizona sexual experiences scale in clinical settings.

BACKGROUND: Approximately 40% of women and 30% of men describe sexual dysfunction, although recognition in medical settings is suboptimal, due to problems in reporting and eliciting concerns relating to sexual function and satisfaction. Screening questionnaires may help to support this aspect of clinical practice. The Arizona sexual experiences scale (ASEX) includes items that quantify sex drive, arousal, vaginal lubrication or penile erection, ability to reach orgasm, and satisfaction from orgasm. METHOD: We investigated the validity and other psychometric properties of the ASEX, and the findings from the populations in which it has been employed, by searching MEDLINE, EMBASE, and Google Scholar using the terms, Arizona sexual experiences scale, Arizona Sexual Experience Questionnaire, and ASEX. We eliminated duplications, letters, and papers not available in English, and grouped the remaining papers into the categories of psychometric, epidemiological, and outcome-based studies. RESULTS: After elimination of letters and duplicates, papers not in English, and preclinical and irrelevant studies, 104 papers were analyzed. The ASEX has excellent internal consistency, scale reliability and strong test-retest reliability. Analyses of variance reveal significant differences in total ASEX scores between patients and controls and between females and males. ASEX appears to be useful in a range of clinical situations including patients with primary sexual dysfunction, specific psychiatric disorders, specific physical illnesses, and treatment emergent sexual dysfunction. DISCUSSION: The ASEX appears to be a reliable instrument for identifying and quantifying sexual dysfunction across a range of populations in various clinical settings. Little is known about its utility in patients with anxiety disorders or relationships between ASEX scores and biological parameters.

Effects of SSRIs on peripheral inflammatory markers in patients with major depressive disorder: A systematic review and meta-analysis.

INTRODUCTION: Peripheral levels of inflammatory markers are elevated in major depressive disorder (MDD). Selective serotonin reuptake inhibitors (SSRIs) affect levels of inflammatory markers in patients with MDD, but studies have reported inconsistent findings. This systematic review and meta-analysis aims to investigate the effects of SSRI treatment on peripheral levels of a range of inflammatory markers in MDD patients. METHODS: Systematic literature search (Pubmed, Web of Science, Embase, Cochrane) for studies published before November 2018. Studies were included if they used SSRI monotherapy and peripheral levels of interleukin (IL)-1ß, IL-2, IL-4, IL-6, IL-10, tumor necrosis factor (TNF)-α, and interferon (IFN)-γ were measured before and after treatment in patients with MDD. Meta-analysis was conducted using Comprehensive Meta-analysis (version 2). Effect sizes were calculated using bias-corrected standardized mean difference (Hedges' g) between pre- and post-treatment. Sub-group analyses, meta-regression and publication bias estimates were undertaken; sensitivity analyses were performed using different estimated pre- and post-treatment correlations and after removing poor quality studies. RESULTS: Twenty two eligible studies including 827 MDD patients were included in the meta-analysis: fifteen studies for IL-6; eleven for TNF-α; eight for IL-10; seven for IL-1ß; six for IL-4; five for IL-2; and four for IFN-γ. The pooled effect estimate indicates SSRI treatment decreased levels of pro-inflammatory markers IL-6 (Hedges' g, -0.418; 95%CI, -0.663 to -0.174; I2 = 89.412), TNF-α (Hedges' g, -0.554; 95%CI, -0.990 to -0.118; I2 = 95.438) and IL-1ß (Hedges' g = -0.574; 95%CI, -1.014 to -0.135; I2 = 91.622), and anti-inflammatory marker IL-10 (Hedges' g = -0.615; 95%CI, -0.989 to -0.242; I2 = 90.406). There were no significant treatment effects on levels of IL-2, IL-4, or IFN-γ. There was a high level of heterogeneity between studies. Sensitivity analyses indicated the robustness of the primary analyses. CONCLUSIONS: The current review and meta-analysis indicates moderate immunomodulating effects of SSRI treatment for MDD, which suggests SSRIs may owe some of their therapeutic effect to their anti-inflammatory properties. High heterogeneity across studies may limit interpretation of the findings and larger randomized clinical trials are warranted.

Effects of SSRIs on peripheral inflammatory cytokines in patients with Generalized Anxiety Disorder.

BACKGROUND: Extensive research into psychoneuroimmunology has led to substantial advances in our understanding of the reciprocal interactions between the central nervous system and the immune system in neuropsychiatric disorders. To date, inflammation has been implicated in the pathogenesis of depression and anxiety. The immunomodulating effects of antidepressants on depression have been reported, however, there is no evidence of the similar effects of antidepressants on anxiety. The aim of the study was to investigate the effects of selective serotonin reuptake inhibitors (SSRIs) on peripheral inflammatory cytokines in patients with first episode generalized anxiety disorder (GAD). METHODS: A prospective cohort design was employed: 42 patients with first episode GAD were treated with either escitalopram or sertraline for 12 weeks. Anxiety was measured by the Generalized Anxiety Disorder Scale and the State Trait Anxiety Inventory, serum pro-inflammatory cytokine levels were measured by the enzyme-linked immunosorbent assay (ELISA), and CRP determined by an immunoturbidimetric method before and after SSRIs treatment RESULTS: Baseline levels of anxiety and pro-inflammatory cytokines including IL-1α, IL-6, IL-8, IL-12, IFN-γ, and CRP were significantly reduced after treatment of SSRIs (p < 0.05 in all cases). In addition, the change of anxiety measures co-vary with the change of peripheral cytokine levels (p < 0.05 in all cases). The regression model revealed that log transformed baseline levels of CRP and IL-6 predicted treatment response (p < 0.05 in both cases). CONCLUSIONS: This study is the first to investigate the effects of SSRIs on pro-inflammatory cytokines in patients with first episode GAD. The findings indicate moderate acute anti-inflammatory effects of SSRIs in GAD, and suggest that these anti-inflammatory effects may underlie anxiolytic effects of SSRIs. The study also indicates that serum levels of CRP and IL-6 may predict treatment response. However, data from randomized controlled trials is warranted to confirm these findings.