Life events in panic disorder-an update on "candidate stressors"

Altered DNA Methylation of the Serotonin Transporter Gene Associated with Early Life Stress and White Matter Microalterations in Korean Patients with Panic Disorder

INTRODUCTION

Changes in the DNA methylation of 5-HTTLPR are associated with the pathophysiology of panic disorder (PD). This study was conducted to investigate the association between stressful life events and the level of 5-HTTLPR methylation in patients with PD. We also examined whether these factors were associated with white matter alterations in psychological trauma-related regions.

METHODS

The participants comprised 232 patients with PD and 93 healthy adults of Korean descent. DNA methylation levels of five cytosine-phosphate-guanine (CpG) sites in the 5-HTTLPR region were analyzed. Voxel-wise statistical analysis of diffusion tensor imaging data was performed within the trauma-related regions.

RESULTS

PD patients showed significantly lower levels of the DNA methylation at 5-HTTLPR 5 CpG sites than healthy controls. In patients with PD, the DNA methylation levels at 5-HTTLPR 5 CpG sites showed significant negative association with the parental separation-related psychological distress, and positive correlations with the fractional anisotropy values of the superior longitudinal fasciculus (SLF) which might be related to trait anxiety.

CONCLUSION

Early life stress was significantly associated with DNA methylation levels at 5-HTTLPR related to the decreased white matter integrity in the SLF region in PD. Decreased white matter connectivity in the SLF might be related to trait anxiety and is vital to the pathophysiology of PD.

Blood transcriptome analysis suggests an indirect molecular association of early life adversities and adult social anxiety disorder by immune-related signal transduction

Social anxiety disorder (SAD) is a psychiatric disorder characterized by severe fear in social situations and avoidance of these. Multiple genetic as well as environmental factors contribute to the etiopathology of SAD. One of the main risk factors for SAD is stress, especially during early periods of life (early life adversity; ELA). ELA leads to structural and regulatory alterations contributing to disease vulnerability. This includes the dysregulation of the immune response. However, the molecular link between ELA and the risk for SAD in adulthood remains largely unclear. Evidence is emerging that long-lasting changes of gene expression patterns play an important role in the biological mechanisms linking ELA and SAD. Therefore, we conducted a transcriptome study of SAD and ELA performing RNA sequencing in peripheral blood samples. Analyzing differential gene expression between individuals suffering from SAD with high or low levels of ELA and healthy individuals with high or low levels of ELA, 13 significantly differentially expressed genes (DEGs) were identified with respect to SAD while no significant differences in expression were identified with respect to ELA. The most significantly expressed gene was MAPK3 (p = 0.003) being upregulated in the SAD group compared to control individuals. In contrary, weighted gene co-expression network analysis (WGCNA) identified only modules significantly associated with ELA (p ≤ 0.05), not with SAD. Furthermore, analyzing interaction networks of the genes from the ELA-associated modules and the SAD-related MAPK3 revealed complex interactions of those genes. Gene functional enrichment analyses indicate a role of signal transduction pathways as well as inflammatory responses supporting an involvement of the immune system in the association of ELA and SAD. In conclusion, we did not identify a direct molecular link between ELA and adult SAD by transcriptional changes. However, our data indicate an indirect association of ELA and SAD mediated by the interaction of genes involved in immune-related signal transduction.

Longitudinal relationship between quality of life and negative life events among adolescents during COVID-19 pandemic: a cross-lagged panel analysis

BACKGROUND

The negative association of quality of life (QoL) and negative life evens (NLEs) among adolescents has been proved by cross-sectional studies, without exploring sex differences. This study aimed to explore the longitudinal associations between QoL and NLEs among adolescents during novel coronavirus disease 2019 (COVID-19) pandemic and whether there are sex or age differences.

METHODS

A stratified cluster sampling was used to select 1421 students in primary school and middle school in Chongqing, China. From November 2020 (T0) to December 2021 (T2), the Adolescent Self-Rating Life Events Checklist and the Adolescent Quality of Life Scale were used to collect 3 waves of data. The correlations between study variables were conducted by the Pearson correlation analyses. The direction and strength of the longitudinal associations were analyzed using cross-lagged panel analyses.

RESULTS

Results showed significant changes in both variables during COVID-19 pandemic (P < 0.001). Cross-sectional analyses showed stable negative correlations between NLEs and QoL stratified by sex or by age (P < 0.001). Sex and age differences in longitudinal relationships were shown by cross-lagged panel analyses. For males, NLEs had a short-term bi-directional association with QoL [βA-D = -(0.091-0.340), P < 0.05]; for females, QoL had a short-term correlation with NLEs [βA = -0.119), βC = -0.109), P < 0.001]. In the youngest age group, NLEs had a short-term bi-directional correlation with QoL [βA-D = -(0.098-0.428), P < 0.05]. There was a short-term association between total QoL and NLEs among students except the 14∼15 year group [βA = -(0.071-0.149), βC = -(0.086-0.119), P < 0.05], the long-term association between total QoL and NLEs was only significant in adolescents aged 14∼15 years (βE = -0.132, P < 0.05). The strength of NLEs was slightly higher than that of total QoL, but lower than that of QoL in each dimension.

CONCLUSION

There were negative longitudinal relationships between NLEs and QoL during COVID-19 pandemic, and the strength of the associations varied across sex or age. Strengthening QoL in different dimensions may be a promising way to reduce NLEs during the pandemic among adolescents, and interventions should be tailored according different sex and ages.

Co-occurring OCD and Panic Disorder: A Review of Their Etiology and Treatment

Estimated rates of co-occurrence between obsessive and compulsive disorder (OCD) and panic disorder (PD) are notable, but vary considerably, with rates from epidemiological and clinical studies ranging from 1.8% to 22% (Rector et al., 2017). We reviewed the current empirical literature on the etiology, treatment, diagnostic assessment, and differential diagnosis of co-occurring OCD/PD. Best practices for cognitive-behavioral treatment, including identifying and addressing treatment barriers are also addressed. Although it is acknowledged in current literature that co-occurring OCD and PD levels may be clinically significant, there remains a need to thoroughly examine the possible consequences and future research directions of this overlap. Future research must continue to elucidate the biological and environmental causes of OCD/PD co-occurrence.

Are Patients at Risk for Developing Panic Disorder After an Emergency Department Visit With Noncardiac Chest Pain?

BACKGROUND

Panic disorder (PD) is common in emergency department (ED) patients with noncardiac chest pain (NCCP). The literature suggests that initially PD-free patients may be at increased risk of developing PD in the months or years following an ED visit.

OBJECTIVES

This study aims to determine the incidence of PD in the 2 years following an ED visit with NCCP and to identify predictors of incident PD.

METHODS

This study was conducted using a longitudinal, observational design. Five hundred and eighty-five patients with NCCP (without PD) were recruited in two EDs. They underwent an interview and completed a series of questionnaires assessing anxiety disorders, perceived social support, psychological distress, anxiety sensitivity, comorbidities, and stressful life events. PD was assessed 6 months, 1 year, and 2 years after the initial interview.

RESULTS

PD incidence was 11.1% (95% confidence interval: 8.7-13.9) in the two years following the baseline assessment. Anxiety sensitivity (odds ratio = 1.08; 95% confidence interval: 1.04-1.11; P < .001) and stress related to life events (odds ratio = 1.14; 95% confidence interval: 1.06-1.24; P = .001) significantly predicted incident PD.

CONCLUSIONS

Patients with NCCP are at high risk for developing PD in the 2 years following an ED visit with NCCP. Anxiety sensitivity and stress related to life events may be promising clinical targets for preventive interventions.

Fear and Coping in Students during the Early Stages of the COVID-19 Pandemic: A Combined Cross-Sectional and Longitudinal Study

The overwhelming impacts of the COVID-19 pandemic have been experienced by individuals across the world. Additional circumstances unique to students affected their studies during the early stages of the pandemic, with changes in living and studying mid-semester. The current study aimed to investigate predictors of fear of COVID-19 in college students during this acute phase using cross-sectional and longitudinal samples. In total, 175 undergraduate students completed an online questionnaire in the spring 2020 semester following lockdown. A subset of 58 students completed a separate survey in fall 2019, which served as a baseline. For the cross-sectional sample, pre-COVID-19 and current living situations did not predict COVID-19 fears. However, a propensity to experience panic was significantly associated with greater COVID-19 fears. How students coped with the pandemic was not associated with COVID-19 fears, although a greater propensity to use denial as a coping style tended to be related to greater COVID-19 fears. In the longitudinal subsample, students showed decreased positive mood and social stress load while depressive mood increased after lockdown. Their preferred coping styles changed, utilizing more self-distraction and acceptance, and less self-blame and substance use. Findings reflect both positive and negative consequences of the pandemic. The unique changes in students' lifestyles will need to be met by tailored interventions.

The interaction effect of early trauma exposure and a diagnosis of panic disorder on cortical thickness

BACKGROUND

Early trauma (ET) is a risk factor for adult psychiatric disorders. ET exposure is known to cause structural brain alterations, particularly in the fronto-temporo-limbic circuitry. ET-related effects on brain development may differ based on individual characteristics and cause different psychiatric outcomes. We investigated the interaction effect of ET exposure and panic disorder (PD) on cortical thickness.

METHODS

Sixty-six participants with PD and 66 healthy controls were enrolled. High-resolution T1-weighted images were acquired, and a whole-brain vertex-based analysis was performed to estimate cortical thickness. The Early Trauma Inventory Self Report-Short Form, Anxiety Sensitivity Inventory-Revised, Panic Disorder Severity Scale, Beck Depression Inventory-II, and Beck Anxiety Inventory were administered.

RESULTS

There was a significant interaction between ET exposure and PD on the mean cortical thickness in the bilateral insula and right pars triangularis. An exploratory correlational analysis revealed a positive correlation between the mean cortical thickness in the left insula and severity of anxiety sensitivity to cardiovascular symptoms in participants with PD.

LIMITATIONS

Our findings may be affected by recall bias because this study is limited by its retrospective cross-sectional design.

CONCLUSIONS

Our findings suggest that ET exposure may affect brain structures differently based on a diagnosis of PD. Furthermore, individual variations in brain alterations after ET may confer trait vulnerability that triggers the development of PD. Future longitudinal studies are warranted to elucidate the neurobiological mechanisms underlying ET and psychiatric outcomes.

Therapygenetic effects of 5-HTTLPR on cognitive-behavioral therapy in anxiety disorders: A meta-analysis

There is a recurring debate on the role of the serotonin transporter gene linked polymorphic region (5-HTTLPR) in the moderation of response to cognitive behavioral therapy (CBT) in anxiety disorders. Results, however, are still inconclusive. We here aim to perform a meta-analysis on the role of 5-HTTLPR in the moderation of CBT outcome in anxiety disorders. We investigated both categorical (symptom reduction of at least 50%) and dimensional outcomes from baseline to post-treatment and follow-up. Original data were obtained from ten independent samples (including three unpublished samples) with a total of 2,195 patients with primary anxiety disorder. No significant effects of 5-HTTLPR genotype on categorical or dimensional outcomes at post and follow-up were detected. We conclude that current evidence does not support the hypothesis of 5-HTTLPR as a moderator of treatment outcome for CBT in anxiety disorders. Future research should address whether other factors such as long-term changes or epigenetic processes may explain further variance in these complex gene-environment interactions and molecular-genetic pathways that may confer behavioral change following psychotherapy.

The interaction of 5-HTT variation, recent stress, and resilience on current anxiety levels in adolescents and young adults from the general population

BACKGROUND

Previous work on gene-environment (GxE) interplay concerning anxiety has focused on the interaction of 5-HTTLPR with childhood adversities or traumatic events whereas the impact of recent stressors is understudied, as is the integration of resilience. The current study aimed to investigate the interactive effect of 5-HTTLPR and recent stress on anxiety in adolescents considering resilience as buffer of a GxE risk constellation.

METHOD

In a random population-based sample of 14-21 years old from Dresden, Germany, (N = 1180; genotyped = 942) recent stress (Daily Hassles [DH] Scale, Perceived Stress Scale, Screening Scale of the Trier Inventory for the Assessment of Chronic Stress), resilience (Connor-Davidson resilience scale) and anxiety (Patient Reported Outcome Measurement Information System Anxiety Short Form) were assessed via questionnaire in 2015 or 2016.

RESULTS

Fractional regression models revealed that resilience interacted with recent stress in form of DH as well as recent chronic stress and 5-HTTLPR regarding anxiety. Participants carrying the more active L_A L_A genotype reported consistently higher levels of anxiety when experiencing more DH or more recent chronic stress and having low levels of resilience. When the resilience scores were high, L_A L_A carriers reported the lowest anxiety scores despite DH or recent chronic stress.

CONCLUSION

Findings revealed an interactive relationship between 5-HTTLPR genotype and recent stress suggesting resilience to function as an additional dimension buffering the impact of a GxE risk constellation. Early interventions to build resilience may be useful to prevent an escalation of distress and associated unfavorable health outcomes.

The error-related negativity (ERN) moderates the association between interpersonal stress and anxiety symptoms six months later

Anxiety disorders are often preceded by interpersonal stress; however, most individuals who experience stress do not develop anxiety, making it difficult to predict who is most susceptible to stress. One proposed trans-diagnostic neural risk marker for anxiety is the error-related negativity (ERN), a negative deflection in the event-related potential waveform occurring within 100 ms of error commission. The present study sought to investigate whether interpersonal stress experienced over the course of a year interacts with ERN magnitude to prospectively predict anxiety symptoms. A sample of 57 emerging adults performed an arrow flanker task to elicit the ERN at the start of the academic school year (time one). Toward the end of the academic year (time two), participants reported on past-year interpersonal stress and anxiety symptoms. Stress interacted with ERN magnitude to predict anxiety symptoms, whereby, for individuals with an enhanced ERN at time one, greater interpersonal stress over the course of a year was significantly associated with increased anxiety symptoms at time two, even controlling for anxiety symptoms at time one. These findings suggest that enhanced performance monitoring may render individuals more susceptible to the adverse effects of interpersonal stress, thereby increasing risk for heightened anxiety.

Higher Rightward Laterality of the Hippocampal Tail and Its Association with Early Trauma in Panic Disorder

OBJECTIVE

Early trauma (ET) is widely recognized as a contributing factor to the development of panic disorder (PD) in patients. However, there is a dearth of research on the specific volumes of hippocampal subregions and their laterality with respect to ET and PD.

METHODS

A total of 30 subjects with PD and 30 age- and sex-matched healthy controls (HCs) were included in this study. All the subjects were evaluated by 3T-magnetic resonance imaging. FreeSurfer version 6.0 was used for volumetric analysis of the hippocampal subregions and their laterality. A shortened version of the Early Trauma Inventory Self Report (ETISR) as well as Anxiety Sensitivity Inventory-Revised (ASI-R), and Panic Disorder Severity Scale were utilized for analysis.

RESULTS

Multivariate analysis of variance showed that the volume of the right hippocampal tail and laterality indices (LIs) of the hippocampal body and tail were significantly larger in subjects with PD relative to HCs. The significance of the observations remained unchanged after multivariate analysis of covariance, controlling for age, sex, years of education, medication, depressive symptoms, and intracranial volume as covariates. The LIs of the hippocampal tails that showed a significant correlation to ETISR emotional and physical subscales were also associated with ASI-R for cardiovascular symptoms in PD.

CONCLUSION

Our study displayed an increased rightward lateralization of the hippocampal tails in subjects with PD compared with HCs. This alteration in the brain, which was associated with early emotional and physical trauma, would negatively affect anxiety sensitivity to cardiovascular symptoms in subjects with PD.

Panic disorder: attack of fear or acute attack of solitude? Convergences between affective neuroscience and phenomenological-Gestalt perspective

There is consensus among scientists in considering Panic Attack (PA) as an exaggerated fear response triggered by intense activation of the amygdala and related Fear brain network. Current guidelines for treatment (e.g. National Institute for Clinical Excellence, NICE, 2011), that are based on this view, do not achieve satisfactory results: one-third of all treated patients report persistent PAs and other Panic Disorder (PD) symptoms, and several meta-analyses report the high likelihood of relapse. Here we review findings from Affective Neuroscience and clinical insights from a phenomenological-Gestalt perspective, putting into question the link between PD and activation of the Fear brain network. We propose an alternative hypothesis about PD etiology: PD is mainly connected to the Panic system, that is activated in situations of separation from affective support and overexposure to the environment. In our view, PA can be understood as an acute attack of solitude which is not adequately recognized by the patient due to the intervention of a dissociative component that makes it impossible to integrate all neuro-physiological responses activated by the Panic/Separation brain system within a coherent emotional feeling. This perspective can explain many evidences that otherwise remain isolated elements without a comprehensive frame: i.e., the association with agoraphobia, the onset of PD during adolescence and young adult life, the need to be accompanied, the connection with air hunger and other respiratory anomalies, the efficacy of antidepressants and the lack of activation of the Hypothalamic-Pituitary-Adrenal (HPA) axe. We discuss future steps to test this hypothesis and the consequences for psychotherapeutic treatment.

Serotonergic influence on depressive symptoms and trait anxiety is mediated by negative life events and frontal activation in children and adolescents

Depression and anxiety are common in childhood and adolescence. Even though cardinal symptoms differ, there is a considerable overlap regarding the pathogenic influence of serotonergic innervation, negative life experience, disturbed emotion perception/affect regulation, and impaired neural functioning in the fronto-limbic circuit. In this study, we examined the effect of the 5-HTTLPR/rs25531 genotype on depressive symptoms and trait anxiety under the consideration of the amount of negative life events in healthy children and adolescents (N = 389). In a subsample of 49 subjects, we performed fMRI to add fronto-limbic brain activation as a second interacting factor. Across all subjects, negative life events moderated the influence of the 5-HTTLPR/rs25531 genotype on both depressive symptoms and trait anxiety. In the fMRI subsample, 5-HTTLPR/rs25531 S + S/L_G + S/L_A + L_GL_A + L_GL_G genotype-associated left middle frontal gyrus (MFG) activation mediated the influence of 5-HTTLPR/rs25531 genotype on depressive symptoms, however, only in combination with negative life events. Genetic influence on trait anxiety was predominantly mediated by negative life events; only L_AL_A genotype-specific activation in the right MFG worked as a mediator in combination with negative life events. The present findings hint towards distinct mechanisms mediating the influence of 5-HTTLPR/rs25531 genotype on depressive symptoms and anxiety, with negative life events playing a crucial role in both phenotypes. With regard to depressive symptoms, however, this influence was only visible in combination with MFG activation, whereas, in anxiety, it was independent of brain activation.

Early sexual trauma is related with the tapetum in patients with panic disorder

BACKGROUND

Early trauma exposure is suggested to confer a greater risk for the development of panic disorder (PD) by altering neurodevelopmental processes. A body of studies have shown that white matter microstructures, particularly in the fronto-limbic and callosal regions, could be affected by a history of early trauma in patients with PD. The tapetum, the extended posterior part of the corpus callosum connecting the bilateral temporal lobes, has not yet been studied regarding its relationship with early trauma, especially sexual one.

METHODS

Seventy participants with PD, sixty age- and sex-matched healthy controls were enrolled. The Early Trauma Inventory Self Report-Short Form (ETISR-SF), Neuroticism Scale, and Panic Disorder Severity Scale (PDSS) were administered. Voxel-wise statistical analysis of diffusion tensor imaging data was performed within the bilateral tapetum regions using Tract-Based Spatial Statistics (TBSS).

RESULTS

In participants with PD, higher levels of sexual trauma were significantly associated with the increased fractional anisotropies (FAs) in a cluster of the right tapetum. Exploratory correlation analysis revealed that FAs in this cluster were significantly correlated with higher neuroticism and poorer treatment response after one year of pharmacotherapy. No significant correlation was found between FAs of the right tapetum cluster and the PDSS scores.

LIMITATIONS

The possibility of retrospective recall bias for early trauma cannot be completely ruled out.

CONCLUSIONS

The findings of this study suggest that the right tapetum may serve as a potential neural marker of early sexual trauma in patients with PD and contribute to personal vulnerability and poorer treatment outcome after pharmacotherapy.

Role of MicroRNAs in Anxiety and Anxiety-Related Disorders

MicroRNAs as critical regulators of gene expression important for functions including neuronal development, synapse formation, and synaptic plasticity have been linked with the regulation of neurobiological systems that underlie anxiety processing in the brain. In this chapter, we give an update on associative evidence linking regulation of microRNAs with anxiety- and trauma-related disorders. Moving beyond correlative research, functional studies have emerged recently that explore causal relationships between microRNA expression and anxiety-like behavior. It has been demonstrated that experimental up- or downregulation of the candidate microRNAs in important nodes of the anxiety neurocircuitry can indeed modulate anxiety-related behavior in animal models. Improved methodologies for assessing microRNA-mediated modulation have aided such functional studies, revealing a number of anxiety-regulating microRNAs including miR-15a, miR-17-92, miR-34, miR-101, miR-124, miR-135, and miR-155. Important functional target genes of these identified microRNAs are associated with specific neurotransmitter/neuromodulator signaling, neurotrophin (e.g., BDNF) expression and other aspects of synaptic plasticity, as well as with stress-regulatory/hypothalamic-pituitary-axis function. Furthermore, microRNAs have been revealed that are regulated in distinct brain regions following various anxiety-attenuating strategies. These include pharmacological treatments such as antidepressants and other drugs, as well as non-pharmacological interventions such as fear extinction/exposure therapy or positive stimuli such as exposure to environmental enrichment. These are first indications for a role for microRNAs in the mechanism of action of anxiolytic treatments. As research continues, there is much hope that a deeper understanding of the microRNA-mediated mechanisms underlying anxiety-related disorders could open up possibilities for future novel biomarker and treatment strategies.

Identification and medical utilization of newly diagnosed panic disorder: A Nationwide case-control study

OBJECTIVE

Ascertaining comorbid illnesses and patterns of medical utilization early in the course of psychiatric illness can help identify patients with panic disorder. We investigated how such cases were diagnosed and the comorbidities associated with newly diagnosed panic disorder in a nationwide database.

METHODS

We enrolled a large representative cohort of the general population in Taiwan (N = 1000,000) and selected 9759 cases of panic disorder from January 1, 2000 to December 31, 2013. The distribution of the departments in which the cases were identified and the medical utilization 12 months before diagnosis were analyzed. Based on a nested case-control study, four controls were randomly selected for each case and matched for sex, age, and incidence year. Conditional logistic regression was used to explore the factors associated with newly-diagnosed panic disorder such as demographic factors, concomitant medications, and physical and psychiatric comorbidities.

RESULTS

Most (58.5%) cases of panic disorder were diagnosed in the psychiatry department, whereas only 3.7% were identified in the emergency department. Before diagnosis, the patients frequently visited the departments of internal medicine, family practice, and Chinese herbal medicine. A multivariate analysis revealed a higher number of physical and psychiatric comorbidities before diagnosis in the cases compared with the controls, especially depressive disorder and other anxiety disorders.

CONCLUSIONS

Individuals with certain comorbidities and patterns of medical utilization are more likely to be diagnosed with panic disorder. We suggest providing more training to general practitioners and emergency physicians for the early diagnosis of panic disorder.

The Diagnosis and Treatment of Anxiety Disorders

BACKGROUND

Anxiety disorders are the most common type of mental illness in Europe, with a 12-month prevalence of 14% among persons aged 14 to 65. Their onset is usually in adolescence or early adulthood. The affected patients often develop further mental or somatic illnesses (sequential comorbidity).

METHODS

This review is based on pertinent publications retrieved by a selective search in PubMed.

RESULTS

The group of anxiety disorders includes generalized anxiety disorder (GAD), phobic disorders, panic disorders, and two disorders that are often restricted to childhood-separation anxiety and selective mutism. A comprehensive differential diag- nostic evaluation is essential, because anxiety can be a principal manifestation of other types of mental or somatic illness as well. Psychotherapy and treatment with psychoactive drugs are the therapeutic strategies of first choice. Of all types of psycho- therapy, cognitive behavioral therapy has the best documented efficacy. Modern antidepressants are the drugs of first choice for the treatment of panic disorders, agoraphobia, social phobia, and GAS; pregabalin is a further drug of first choice for GAS.

CONCLUSION

In general, anxiety disorders can now be effectively treated. Patients should be informed of the therapeutic options and should be involved in treatment planning. Current research efforts are centered on individualized and therefore, it is hoped, even more effective treatment approaches than are available at present.

Multi-omics analysis identifies mitochondrial pathways associated with anxiety-related behavior

Stressful life events are major environmental risk factors for anxiety disorders, although not all individuals exposed to stress develop clinical anxiety. The molecular mechanisms underlying the influence of environmental effects on anxiety are largely unknown. To identify biological pathways mediating stress-related anxiety and resilience to it, we used the chronic social defeat stress (CSDS) paradigm in male mice of two inbred strains, C57BL/6NCrl (B6) and DBA/2NCrl (D2), that differ in their susceptibility to stress. Using a multi-omics approach, we identified differential mRNA, miRNA and protein expression changes in the bed nucleus of the stria terminalis (BNST) and blood cells after chronic stress. Integrative gene set enrichment analysis revealed enrichment of mitochondrial-related genes in the BNST and blood of stressed mice. To translate these results to human anxiety, we investigated blood gene expression changes associated with exposure-induced panic attacks. Remarkably, we found reduced expression of mitochondrial-related genes in D2 stress-susceptible mice and in exposure-induced panic attacks in humans, but increased expression of these genes in B6 stress-susceptible mice. Moreover, stress-susceptible vs. stress-resilient B6 mice displayed more mitochondrial cross-sections in the post-synaptic compartment after CSDS. Our findings demonstrate mitochondrial-related alterations in gene expression as an evolutionarily conserved response in stress-related behaviors and validate the use of cross-species approaches in investigating the biological mechanisms underlying anxiety disorders.

Genetics of Anxiety Disorders

PURPOSE OF REVIEW

Anxiety disorders are among the most common mental disorders with a lifetime prevalence of over 20%. Clinically, anxiety is not thought of as a homogenous disorder, but is subclassified in generalized, panic, and phobic anxiety disorder. Anxiety disorders are moderately heritable. This review will explore recent genetic and epigenetic approaches to anxiety disorders explaining differential susceptibility risk.

RECENT FINDINGS

A substantial portion of the variance in susceptibility risk can be explained by differential inherited and acquired genetic and epigenetic risk. Available data suggest that anxiety disorders are highly complex and polygenic. Despite the substantial progress in genetic research over the last decade, only few risk loci for anxiety disorders have been identified so far. This review will cover recent findings from large-scale genome-wide association studies as well as newer epigenome-wide studies. Progress in this area will likely require analysis of much larger sample sizes than have been reported to date. We discuss prospects for clinical translation of genetic findings and future directions for research.

Childhood trauma dependent anxious depression sensitizes HPA axis function

Anxious depression is a common subtype of major depressive disorder (MDD) and is associated with greater severity and poorer outcome. Alterations of the hypothalamic-pituitary-adrenal (HPA) axis, especially of the glucocorticoid receptor (GR) function, are often observed in MDD, but evidence lacks for anxious depression. Childhood adversity is known to influence both the HPA axis and risk of MDD. Therefore, we investigated GR-function in anxious depression dependent on childhood adversity. We enrolled 144 depressed in-patients (49.3% females). Anxious depression was defined using the Hamilton Depression Rating Scale (HAM-D) anxiety/somatization factor score ≥7. Blood draws were performed at 6 pm before and 3 h after 1.5 mg dexamethasone ingestion for measurement of cortisol, ACTH and blood count to assess GR-function and the immune system. In a subgroup of n = 60 FKBP5 mRNA controlled for FKBP5 genotype was measured before and after dexamethasone. Childhood adversity was evaluated using the Childhood Trauma Questionnaire (CTQ). We identified 78 patients (54.2%) with anxious depression who showed a greater severity and worse outcome. These patients were more often exposed to sexual abuse (30% vs. 16%/p = 0.04) and emotional neglect (76% vs. 58%/p = 0.02) than patients with non-anxious depression. Anxious depressed patients showed an enhanced GR-induced FKBP5 mRNA expression (F = 5.128; p = 0.03) and reduced cortisol levels, partly dependent on sexual abuse (F = 7.730; p = 0.006). Additionally, the GR-induced leukocyte response was enhanced in patients with sexual abuse (F = 7.176; p = 0.008). Anxious depression in dependence of childhood trauma is associated with heightened sensitivity of the HPA axis and the immune system which should be considered for treatment algorithms and targets.

An improved method for counting stressful life events (SLEs) when predicting mental health and wellness

OBJECTIVE

Checklists for registering stressful life events (SLEs) generally correlate negatively, but weakly, with mental health outcome measures. Thus, the present study examined various methodological approaches for improving these relationships.

DESIGN

A total of 1679 participants (women = 943, men = 736, M age-39.8) were randomly drawn from the general Norwegian population (response rate 34%). This prospective cohort study included two follow-ups at 10 (n = 1181) and 23 months (n = 942).

MAIN OUTCOME MEASURES

Satisfaction with life and absence of psychological distress (i.e. anxiety and depression) represented a joint measure for indexing 'mental wellness' (MW).

RESULTS

A simple count of SLEs weakly predicted MW, as expected, whereas the addition of a moderator (i.e. manageability of the event) substantially improved predictive power. Four additional moderators were examined: duration, impact, help-seeking and time since onset, but these were non-significant after inserting manageability into the model. This SLE counting method also retained its predictive power after including multiple criterion-related variables that substantially adjusted the longitudinal statistical model.

CONCLUSION

This new SLE counting method exhibited a considerable improvement to predicting mental health and well-being. It is well suited for use in epidemiological research requiring a short SLE checklist format with high predictive power.

Anxiety disorders and CRP in a population cohort study with 54,326 participants: The LifeLines study

OBJECTIVES

Growing evidence indicates that inflammatory processes may play a role in the pathogenesis of anxiety disorders. Nevertheless, much remains to be learned about the involvement of inflammation, including C-reactive protein (CRP), in specific anxiety disorders. This study examines the relation between anxiety disorders and CRP.

METHODS

Associations of serum CRP with anxiety disorders were determined in a large population study (n = 54,326 participants, mean age = 47 years; 59% female), the LifeLines cohort. Depressive and anxiety disorders (generalized anxiety disorder, social anxiety phobia, panic disorder with or without agoraphobia and agoraphobia without panic disorder) were assessed using the Mini-International Neuropsychiatric Interview.

RESULTS

Anxiety disorders, with the exception of social anxiety disorder, were significantly associated with increased CRP. After adjusting for demographics, life style factors, health factors, medication use, depression, and psychological stressors, CRP remained significantly associated with panic disorder with agoraphobia (β = 0.01, P = .013). Moreover, CRP levels were significantly higher in people with panic disorder with agoraphobia compared to other anxiety disorders, independent of all covariates (F = 3.00, df = 4, P = .021).

CONCLUSIONS

Panic disorder with agoraphobia is associated with increased CRP, although the effect size of this association is small. This indicates that neuroinflammatory mechanisms may play a potential role in its pathophysiology.

The microbiome as a novel paradigm in studying stress and mental health

At the intersection between neuroscience, microbiology, and psychiatry, the enteric microbiome has potential to become a novel paradigm for studying the psychobiological underpinnings of mental illness. Several studies provide support for the view that the enteric microbiome influences behavior through the microbiota-gut-brain axis. Moreover, recent findings are suggestive of the possibility that dysregulation of the enteric microbiota (i.e., dysbiosis) and associated bacterial translocation across the intestinal epithelium may be involved in the pathophysiology of stress-related psychiatric disorders, particularly depression. The current article reviews preliminary evidence linking the enteric microbiota and its metabolites to psychiatric illness, along with separate lines of empirical inquiry on the potential involvement of psychosocial stressors, proinflammatory cytokines and neuroinflammation, the hypothalamic-pituitary-adrenal axis, and vagal nerve activation, respectively, in this relationship. Finally, and drawing on these independent lines of research, an integrative conceptual model is proposed in which stress-induced enteric dysbiosis and intestinal permeability confer risk for negative mental health outcomes through immunoregulatory, endocrinal, and neural pathways. (PsycINFO Database Record

Assessing the interplay of childhood adversities with more recent stressful life events and conditions in predicting panic pathology among adults from the general population

BACKGROUND

Although research suggests that (a) childhood adversities and more recent stressful life events/conditions are risk factors for panic pathology and that (b) early life stress increases vulnerability to later psychopathology, it remains unclear whether childhood adversities amplify the association between more recent stressful life events/conditions and panic pathology.

METHODS

Data were derived from a general population sample (Study of Health in Pomerania, SHIP). Lifetime panic pathology was assessed with the Munich Composite International Diagnostic Interview (M-CIDI). Childhood adversities (emotional, physical and sexual abuse; emotional and physical neglect) were assessed with the Childhood Trauma Questionnaire (CTQ). More recent separation/loss events and long-lasting stressful conditions were assessed with the Stralsund Life Event List (SEL). Individuals with lifetime panic pathology (fearful spell, panic attack or panic disorder, N = 286) were compared to controls without any psychopathology (N = 286, matched for sex and age).

RESULTS

Conditional logistic regressions revealed that childhood adversities as well as more recent separation/loss events and long-lasting stressful conditions were associated with panic pathology (OR 1.1-2.5). Moreover, more recent separation/loss events - but not long-lasting stressful conditions - interacted statistically with each of the examined childhood adversities except for sexual abuse in predicting panic pathology (OR 1.1-1.3). That is, separation/loss events were associated more strongly with panic pathology among individuals with higher childhood adversities.

LIMITATIONS

Data were assessed retrospectively and might be subject to recall biases.

CONCLUSIONS

Findings suggest that early childhood adversities amplify the risk of developing panic pathology after experiencing separation or loss events.

Fornix microalterations associated with early trauma in panic disorder

BACKGROUND

It is well accepted that panic disorder (PD) is associated with early trauma, and that the limbic systems are one of the main structures involved in PD pathophysiology. However, previous studies have not addressed the relationship between early trauma and major limbic white-matter (WM) structures in PD.

METHODS

Participants enrolled in the study consisted of 53 right-handed patients with PD and 21 healthy controls (HC). The Early Trauma Inventory Self Report-Short Form (ETISR-SF), Anxiety Sensitivity Inventory-Revised (ASI-R), and the Albany Panic and Phobia Questionnaire (APPQ) were applied in the study. Tract-based spatial statistics were used for diffusion tensor magnetic resonance imaging analysis.

RESULTS

Among the patients with PD, the fractional anisotropy (FA) values of the fornix body in major limbic WM regions showed significant negative correlation with the ETISR-SF total score, while the scores of mean diffusivity (MD), axial diffusivity (AD) and radial diffusivity (RD) in the same region of fornix had significant positive correlation with those scores (p<0.05; FWE corrected). Further significant correlation was observed between these four scores and the measures of symptom severity in PD, such as that in ASI-R and APPQ in the same region.

LIMITATIONS

Recall bias is possible in evaluating early trauma in the participants.

CONCLUSIONS

The current study suggests a significant association of early trauma with the fornix body possibly through axons and myelin disruptions within major limbic structures in PD. A multi-centered large sample will be needed to confirm these findings.

Distinct responses to predictable and unpredictable threat in anxiety pathologies: effect of panic attack

Background

Delineating specific clinical phenotypes of anxiety disorders is a crucial step toward better classification and understanding of these conditions. The present study sought to identify differential aversive responses to predictable and unpredictable threat of shock in healthy comparisons and in non-medicated anxiety patients with and without a history of panic attacks (PAs).

Method

143 adults (72 healthy controls; 71 patients with generalized anxiety disorder (GAD) or/and social anxiety disorder (SAD), 24 with and 47 without PAs) were exposed to three conditions: 1) predictable shocks signaled by a cue, 2) unpredictable shocks, and 3) no shock. Startle magnitude was used to assess aversive responses.

Results

Across disorders, a PA history was specifically associated with hypersensitivity to unpredictable threat. By disorder, SAD was associated with hypersensitivity to predictable threat, whereas GAD was associated with exaggerated baseline startle.

Conclusions

These results identified three physiological patterns. The first is hypersensitivity to unpredictable threat in individuals with PAs. The second is hypersensitivity to predictable threat, which characterizes SAD. The third is enhanced baseline startle in GAD, which may reflect propensity for self-generated anxious thoughts in the absence of imminent danger. These results inform current thinking by linking specific clinical features to particular physiology profiles.

Gender Differences of Stressful Life Events, Coping Style, Symptom Severity, and Health-Related Quality of Life in Patients With Panic Disorder

Although affective disorders have been known to have sex differences in the associated clinical characteristics and quality of life (QOL), sex differences among patients with panic disorder (PD) have remained relatively unexplored in Korea. We examined the sex differences in different types of stressful life events (SLEs), coping styles, symptom severity, and health-related QOL (HRQOL) in patients with PD. Data from 291 female and 254 male participants diagnosed with PD were analyzed using a structured clinical interview following the Diagnostic and Statistical Manual of Mental Disorders, 4th Edition criteria. Females with PD reported more SLEs including separation issues, physical illness or disability, and pregnancy-related problems than males. They also reported lower levels of confrontation and help-seeking coping strategies and higher levels of agoraphobia in symptom severity than males. The HRQOL of females with PD was significantly lower than male in physical functioning of HRQOL. This study suggests that the patient's sex is relevant to the assessment and treatment of PD.

Impact of childhood trauma on course of panic disorder: contribution of clinical and personality characteristics

OBJECTIVE

To investigate the impact of childhood trauma on the clinical course of panic disorder and possible contributing factors.

METHOD

Longitudinal data of 539 participants with a current panic disorder were collected from the Netherlands Study of Depression and Anxiety (NESDA). Childhood trauma was assessed with a structured interview and clinical course after 2 years with a DSM-IV-based diagnostic interview and the Life Chart Interview.

RESULTS

At baseline, 54.5% reported childhood trauma, but this was not predictive of persistence of panic disorder. Emotional neglect and psychological abuse were associated with higher occurrence of anxiety disorders other than panic disorder (social phobia) and with higher chronicity of general anxiety symptoms (anxiety attacks or episodes and avoidance). Baseline clinical features (duration and severity of anxiety and depressive symptoms) and personality traits (neuroticism and extraversion) accounted for roughly 30-60% of the total effect of childhood trauma on chronicity of anxiety symptoms and on occurrence of other anxiety disorders.

CONCLUSION

After two years, childhood trauma is associated with chronicity of anxiety symptoms and occurrence of social phobia, rather than persistence of panic disorder. These relationships are partially accounted for by duration and severity of anxiety and depressive symptoms, and neuroticism and extraversion.

The Neurobiology of Panic: A Chronic Stress Disorder

Panic disorder is an often chronic and impairing human anxiety syndrome, which frequently results in serious psychiatric and medical comorbidities. Although, to date, there have been many advances in the diagnosis and treatment of panic disorder, its pathophysiology still remains to be elucidated. In this review, recent evidence for a neurobiological basis of panic disorder is reviewed with particular attention to risk factors such as genetic vulnerability, chronic stress, and temperament. In addition, neuroimaging data are reviewed which provides support for the concept of panic disorder as a fear network disorder. The potential impact of the National Institute of Mental Health Research Domain Criteria constructs of acute and chronic threats responses and their implications for the neurobiology of panic disorder are also discussed.

Oxytocin and Anxiety Disorders

In the present chapter, we review the literature focusing on oxytocin (OT)-centered research in anxiety spectrum conditions, comprising separation anxiety disorder, specific phobias, social anxiety disorder (SAD), panic disorder, generalized anxiety disorder, and anxiety-related endophenotypes (e.g., trust behavior, behavioral inhibition, neuroticism, and state/trait anxiety). OT receptor gene (OXTR) polymorphisms have been implicated in gene-environment interactions with attachment style and childhood maltreatment and to influence clinical outcomes, including SAD intensity and limbic responsiveness. Epigenetic OXTR DNA methylation patterns have emerged as a link between categorical, dimensional, neuroendocrinological, and neuroimaging SAD correlates, highlighting them as potential peripheral surrogates of the central oxytocinergic tone. A pathophysiological framework of OT integrating the dynamic nature of epigenetic biomarkers and the summarized genetic and peripheral evidence is proposed. Finally, we emphasize opportunities and challenges of OT as a key network node of social interaction and fear learning in social contexts. In conjunction with multi-level investigations incorporating a dimensional understanding of social affiliation and avoidance in anxiety spectrum disorders, these concepts will help to promote research for diagnostic, state, and treatment response biomarkers of the OT system, advancing towards indicated preventive interventions and personalized treatment approaches.

A developmentally informed perspective on the relation between stress and psychopathology: when the problem with stress is that there is not enough

A common tenet of several prominent theories of stress and psychopathology (e.g., stress exposure) is that experiencing high rates of life stressors is associated with greater risk for negative mental health outcomes. Although there has been substantial empirical support for this position, another possibility that has received considerably less attention to date is that early life stressors may share a curvilinear rather than monotonic relation with psychological well-being. In what has been termed the "steeling effect," "stress inoculation," and "antifragility," exposure to moderate stressors early in life may confer resilience to potential detrimental effects of later stressors. An interesting implication of this model is that low levels of early life stressors, relative to normatively moderate rates, may be associated with greater sensitivity to future stressors. The present article reviews preliminary evidence consistent with this possibility, drawing on behavioral and neurobiological studies in animal models, and the more modest literature on neurocognitive, psychological, and psychophysiological functioning in humans. Limitations of the clinical literature and possible directions for future research are discussed, including naturalistic longitudinal studies with clinical outcomes, and for research examining moderators and mechanisms, across multiple levels of analysis (e.g., cognitive, immunological, and neurobiological).

Biological markers for anxiety disorders, OCD and PTSD - a consensus statement. Part I: Neuroimaging and genetics

OBJECTIVES

Biomarkers are defined as anatomical, biochemical or physiological traits that are specific to certain disorders or syndromes. The objective of this paper is to summarise the current knowledge of biomarkers for anxiety disorders, obsessive-compulsive disorder (OCD) and post-traumatic stress disorder (PTSD).

METHODS

Findings in biomarker research were reviewed by a task force of international experts in the field, consisting of members of the World Federation of Societies for Biological Psychiatry Task Force on Biological Markers and of the European College of Neuropsychopharmacology Anxiety Disorders Research Network.

RESULTS

The present article (Part I) summarises findings on potential biomarkers in neuroimaging studies, including structural brain morphology, functional magnetic resonance imaging and techniques for measuring metabolic changes, including positron emission tomography and others. Furthermore, this review reports on the clinical and molecular genetic findings of family, twin, linkage, association and genome-wide association studies. Part II of the review focuses on neurochemistry, neurophysiology and neurocognition.

CONCLUSIONS

Although at present, none of the putative biomarkers is sufficient and specific as a diagnostic tool, an abundance of high-quality research has accumulated that will improve our understanding of the neurobiological causes of anxiety disorders, OCD and PTSD.

Influence of 5-HTT variation, childhood trauma and self-efficacy on anxiety traits: a gene-environment-coping interaction study

Environmental vulnerability factors such as adverse childhood experiences in interaction with genetic risk variants, e.g., the serotonin transporter gene linked polymorphic region (5-HTTLPR), are assumed to play a role in the development of anxiety and affective disorders. However, positive influences such as general self-efficacy (GSE) may exert a compensatory effect on genetic disposition, environmental adversity, and anxiety traits. We, thus, assessed childhood trauma (Childhood Trauma Questionnaire, CTQ) and GSE in 678 adults genotyped for 5-HTTLPR/rs25531 and their interaction on agoraphobic cognitions (Agoraphobic Cognitions Questionnaire, ACQ), social anxiety (Liebowitz Social Anxiety Scale, LSAS), and trait anxiety (State-Trait Anxiety Inventory, STAI-T). The relationship between anxiety traits and childhood trauma was moderated by self-efficacy in 5-HTTLPR/rs25531 LALA genotype carriers: LALA probands maltreated as children showed high anxiety scores when self-efficacy was low, but low anxiety scores in the presence of high self-efficacy despite childhood maltreatment. Our results extend previous findings regarding anxiety-related traits showing an interactive relationship between 5-HTT genotype and adverse childhood experiences by suggesting coping-related measures to function as an additional dimension buffering the effects of a gene-environment risk constellation. Given that anxiety disorders manifest already early in childhood, this insight could contribute to the improvement of psychotherapeutic interventions by including measures strengthening self-efficacy and inform early targeted preventive interventions in at-risk populations, particularly within the crucial time window of childhood and adolescence.

Does low coping efficacy mediate the association between negative life events and incident psychopathology? A prospective-longitudinal community study among adolescents and young adults

AIMS

To prospectively examine whether negative life events (NLE) and low perceived coping efficacy (CE) increase the risk for the onset of various forms of psychopathology and low CE mediates the associations between NLE and incident mental disorders.

METHODS

A representative community sample of adolescents and young adults (N = 3017, aged 14-24 at baseline) was prospectively followed up in up to three assessment waves over 10 years. Anxiety, depressive and substance use disorders were assessed at each wave using the DSM-IV/M-CIDI. NLE and CE were assessed at baseline with the Munich Event List and the Scale for Self-Control and Coping Skills. Associations (odds ratios, OR) of NLE and CE at baseline with incident mental disorders at follow-up were estimated using logistic regressions adjusted for sex and age.

RESULTS

NLE at baseline predicted the onset of any disorder, any anxiety disorder, panic disorder, agoraphobia, generalised anxiety disorder, any depression, major depressive episodes, dysthymia, any substance use disorder, nicotine dependence and abuse/dependence of illicit drugs at follow-up (OR 1.02-1.09 per one NLE more). When adjusting for any other lifetime disorder prior to baseline, merely the associations of NLE with any anxiety disorder, any depression, major depressive episodes, dysthymia and any substance use disorder remained significant (OR 1.02-1.07). Low CE at baseline predicted the onset of any disorder, any anxiety disorder, agoraphobia, generalised anxiety disorder, any depression, major depressive episodes, dysthymia, any substance use disorder, alcohol abuse/dependence, nicotine dependence and abuse/dependence of illicit drugs at follow-up (OR 1.16-1.72 per standard deviation). When adjusting for any other lifetime disorder prior to baseline, only the associations of low CE with any depression, major depressive episodes, dysthymia, any substance use disorder, alcohol abuse/dependence, nicotine dependence and abuse/dependence of illicit drugs remained significant (OR 1.15-1.64). Low CE explained 9.46, 13.39, 12.65 and 17.31% of the associations between NLE and any disorder, any depression, major depressive episodes and dysthymia, respectively. When adjusting for any other lifetime disorder prior to baseline, the reductions in associations for any depression (9.77%) and major depressive episodes (9.40%) remained significant, while the reduction in association for dysthymia was attenuated to non-significance (p-value > 0.05).

CONCLUSIONS

Our findings suggest that NLE and low perceived CE elevate the risk for various incident mental disorders and that low CE partially mediates the association between NLE and incident depression. Subjects with NLE might thus profit from targeted early interventions strengthening CE to prevent the onset of depression.

Genetics of anxiety disorders: Genetic epidemiological and molecular studies in humans

This review provides a broad overview of the state of research in the genetics of anxiety disorders (AD). Genetic epidemiological studies report a moderate level of familial aggregation (odds ratio: 4-6) and heritability estimates are about 30-50%. Twin studies suggest that the genetic architecture of AD is not isomorphic with their classifications, sharing risk factors with each other. So far, linkage and association studies of AD have produced inconclusive results. Genome-wide association studies of AD can provide an unbiased survey of common genetic variations across the entire genome. Given the shared causes of AD that transcend our current diagnostic classifications, clustering anxiety phenotypes into broader groups may be a powerful approach to identifying susceptibility locus for AD. Using such a shared genetic risk factor, meta-analyses of genome-wide association studies of AD conducted by large consortia are needed. Environmental factors also make a substantial contribution to the cause of AD. Although candidate gene studies of gene by environmental (G × E) interaction have appeared recently, no genome-wide search for G × E interactions have been performed. Epigenetic modification of DNA appears to have important effects on gene expression mediating environmental influences on disease risk. Given that G × E can be linked to an epigenetic modification, a combination analysis of genome-wide G × E interaction and methylation could be an alternative method to find risk variants for AD. This genetic research will enable us to utilize more effective strategies for the prevention and treatment of AD in the near future.

From neural to genetic substrates of panic disorder: Insights from human and mouse studies

Fear is an ancestral emotion, an intrinsic defensive response present in every organism. Although fear is an evolutionarily advantageous emotion, under certain pathologies such as panic disorder it might become exaggerated and non-adaptive. Clinical and preclinical work pinpoints that changes in cognitive processes, such as perception and interpretation of environmental stimuli that rely on brain regions responsible for high-level function, are essential for the development of fear-related disorders. This review focuses on the involvement of cognitive function to fear circuitry disorders. Moreover, we address how animal models are contributing to understand the involvement of human candidate genes to pathological fear and helping achieve progress in this field. Multidisciplinary approaches that integrate human genetic findings with state of the art genetic mouse models will allow to elucidate the mechanisms underlying pathology and to develop new strategies for therapeutic targeting.

Impaired Facial Affect Perception in Unaffected Children at Familial Risk for Panic Disorder

Recent studies suggest that impaired processing of facial affect has a familial component and may reflect a marker of liability to psychopathology. This study investigated whether facial affect processing is impaired in offspring with parental panic disorder (PD). Psychiatrically healthy children with parental PD (n = 51) and age and sex matched control children with no parental psychopathology (n = 51) completed a standard facial recognition task. High-risk children made more errors recognizing fearful faces than controls and misattributed fear and angry facial affect as surprised. High-risk females also made more errors recognizing sad faces compared to low risk females and misattributed sadness as fear. No difference emerged for self-rated anxiety while viewing facial expressions. However, self-rated anxiety correlated moderately with misrecognition of fearful facial affect in high-risk children. Overall, our data suggest that the ability to correctly recognize negative facial emotions is impaired in children with parental PD. Further research is needed to confirm if these deficits represent a trait marker of liability for PD and elucidate the contribution of genetic and family environmental influences.

Risk factors for the onset of panic and generalised anxiety disorders in the general adult population: a systematic review of cohort studies

BACKGROUND

We aimed to assess available evidence on risk factors associated with the onset of panic disorder (PD) and/or generalised anxiety disorder (GAD) in cohort studies in the general adult population.

METHODS

Systematic review using MEDLINE, PsycINFO and Embase. Search terms included panic disorder, generalised anxiety disorder, cohort studies and risk factors.

RESULTS

We finally selected 21 studies, involving 163,366 persons with a median follow-up of 5 years. 1) Sociodemographic factors: PD was associated with age, female gender, and few economic resources. GAD was associated with age, non-Hispanics and Blacks, being divorced or widowed, and few economic resources. 2) Psychosocial factors: PD was associated with smoking and alcohol problems. GAD was associated with stressful life events in childhood and adulthood, and personality. 3) Physical and mental health factors: PD was associated with the number of physical diseases suffered and the joint hypermobility syndrome. PD was also associated with a parental history of mental disorders, as well as with other anxiety disorders and other mental health problems in the person affected. GAD was associated with a parental history of mental disorders, as well as with other anxiety disorders and other mental health problems in the person affected, plus already having received psychiatric care.

LIMITATIONS

Few studies examined the same risk factors.

CONCLUSIONS

Sociodemographic, psychosocial and mental-physical health risk factors were determinant for the onset of PD and GAD in the general adult population. These findings could be useful for developing preventive interventions in PD and GAD.

The use of symptom dimensions to investigate the longitudinal effects of life events on depressive and anxiety symptomatology

BACKGROUND

Findings on the association between life events and depression have been quite inconsistent. This could be due to the heterogeneity of traditionally used depression outcomes. The aim of this study was to investigate whether specific symptom dimensions can be used as an alternative to detect more specific life event effects.

METHODS

Participants with/without psychiatric diagnoses were included (n=2252). Dimensions of the tripartite model (General Distress [GD], Anhedonic Depression [AD] and Anxious Arousal [AA]) were assessed at baseline, 1-year and 2-year follow-up. Life events occurring between measurements were assessed retrospectively. Longitudinal associations between life events and dimensional scores were analysed with Linear Mixed Models.

RESULTS

Occurrence of negative life events was associated with increasing GD and AA, and less with AD. Positive life events were associated with decreasing GD and AD, but not with AA. The association between negative life events and AD was larger in the absence of previous psychiatric problems, lending support to a dimension-specific 'kindling' effect. Also, the negative association between negative life events and GD was stronger in those with high neuroticism. Multivariable analyses with individual life events showed that a few strong independent effects remained for each dimension.

LIMITATIONS

Life event reports were retrospective; only three outcome dimensions were used.

CONCLUSIONS

These results show that the effects of life events and modifying factors depend, to an extent, on the symptom domain that is considered as outcome, illustrating the need to account for symptom heterogeneity in etiological life event research.

Neuropeptide S receptor gene (NPSR) and life events: G × E effects on anxiety sensitivity and its subdimensions

OBJECTIVES

The pathogenesis of anxiety is assumed to be interactively influenced by genetic and environmental factors. Thus, a gene-environment interaction (G × E) study of the neuropeptide S receptor gene (NPSR) A/T polymorphism (rs324981) and life events was conducted with respect to anxiety sensitivity (AS) as an intermediate phenotype of anxiety disorders.

METHODS

A sample of 475 healthy German subjects was genotyped for NPSR and assessed for AS, childhood maltreatment (CTQ) and recent life events (LTE). Influences on AS and its subdimensions were determined by a step-wise hierarchical regression and a multiple indicator multiple cause (MIMIC) model.

RESULTS

Significant main effects of NPSR and CTQ as well as significant G × E were observed, with T/T homozygosity and a high CTQ score resulting in increased anxiety sensitivity. MIMIC modelling yielded association of AS subfactor "concern about mental/cognitive incapacitation" and the basal somatic subdimension "concern about physical sensations" to be associated with CTQ and its interaction with NPSR, while the acute somatic subfactor "concern about heart/lung failure" was associated with NPSR and its interaction with LTE.

CONCLUSIONS

Results indicate G × E effects of the more active NPSR rs324981 T allele and life events on AS with differential effects of temporally proximal and distal factors on specific AS subdimensions.

Examining determinants of early and late age at onset in panic disorder: an admixture analysis

Past research demonstrated that age at onset might account for different clinical and etiological characteristics in panic disorder (PD). However, prior research relied on arbitrary choices of age cut-offs. Using a data-driven validated method, this study aimed to examine differences between early and late onset PD in various determinants. Admixture analysis was used to determine the best fitting model of age at onset distribution in PD. Data was collected from 511 individuals (ages 18-65) with PD diagnoses, who participated in the Netherlands Study of Depression and Anxiety (NESDA). DSM-IV comorbidities and various measures of childhood adversities, suicidal behavior, anxiety and depressive symptoms were assessed. The best fitting cut-off score between early and late age at onset groups was 27 years (early age at onset ≤ 27 years). Univariate tests showed that participants with early onset PD were younger and more likely to be female. Early onset PD was associated with agoraphobia, higher frequency of childhood trauma and life events, and higher rates of suicide attempts as compared to late onset PD. Multivariate logistic regression analysis demonstrated that only current age, childhood trauma and agoraphobia remained significantly associated with early onset PD. Findings suggest that 27 years marks two onset groups in PD, which are slightly distinct. Early onset PD is independently associated with exposure to childhood trauma and increased avoidance. This highlights the importance of subtyping age of onset in PD. Clinical implications are further discussed.

A prospective cohort study to refine and validate the Panic Screening Score for identifying panic attacks associated with unexplained chest pain in the emergency department

INTRODUCTION

Panic-like anxiety (panic attacks with or without panic disorder), a highly treatable condition, is the most prevalent condition associated with unexplained chest pain in the emergency department. Panic-like anxiety may be responsible for a significant portion of the negative consequences of unexplained chest pain, such as functional limitations and chronicity. However, more than 92% of panic-like anxiety cases remain undiagnosed at the time of discharge from the emergency department. The 4-item Panic Screening Score (PSS) questionnaire was derived in order to increase the identification of panic-like anxiety in emergency department patients with unexplained chest pain.

METHODS AND ANALYSIS

The goals of this prospective cohort study were to (1) refine the PSS; (2) validate the revised version of the PSS; (3) measure the reliability of the revised version of the PSS and (4) assess the acceptability of the instrument among emergency physicians. Eligible and consenting patients will be administered the PSS in a large emergency department. Patients will be contacted by phone for administration of the criterion standard for panic attacks as well as by a standardised interview to collect information for other predictors of panic attacks. Multivariate analysis will be used to refine the PSS. The new version will be prospectively validated in an independent sample and inter-rater agreement will be assessed in 10% of cases. The screening instrument acceptability will be assessed with the Ottawa Acceptability of Decision Rules Instrument.

ETHICS AND DISSEMINATION

This study protocol has been reviewed and approved by the Alphonse-Desjardins research ethics committee. The results of the study will be presented in scientific conferences and published in peer-reviewed scientific journals. Further dissemination via workshops and a dedicated website is planned.

The interaction of early life experiences with COMT val158met affects anxiety sensitivity

The pathogenesis of anxiety disorders is considered to be multifactorial with a complex interaction of genetic factors and individual environmental factors. Therefore, the aim of this study was to examine gene-by-environment interactions of the genes coding for catechol-O-methyltransferase (COMT) and monoamine oxidase A (MAOA) with life events on measures related to anxiety. A sample of healthy subjects (N = 782; thereof 531 women; mean age M = 24.79, SD = 6.02) was genotyped for COMT rs4680 and MAOA-uVNTR (upstream variable number of tandem repeats), and was assessed for childhood adversities [Childhood Trauma Questionnaire (CTQ)], anxiety sensitivity [Anxiety Sensitivity Index (ASI)] and anxious apprehension [Penn State Worry Questionnaire (PSWQ)]. Main and interaction effects of genotype, environment and gender on measures related to anxiety were assessed by means of regression analyses. Association analysis showed no main gene effect on either questionnaire score. A significant interactive effect of childhood adversities and COMT genotype was observed: Homozygosity for the low-active met allele and high CTQ scores was associated with a significant increment of explained ASI variance [R(2) = 0.040, false discovery rate (FDR) corrected P = 0.04]. A borderline interactive effect with respect to MAOA-uVNTR was restricted to the male subgroup. Carriers of the low-active MAOA allele who reported more aversive experiences in childhood exhibited a trend for enhanced anxious apprehension (R(2) = 0.077, FDR corrected P = 0.10). Early aversive life experiences therefore might increase the vulnerability to anxiety disorders in the presence of homozygosity for the COMT 158met allele or low-active MAOA-uVNTR alleles.

Epigenetic signature of panic disorder: a role of glutamate decarboxylase 1 (GAD1) DNA hypomethylation?

Glutamate decarboxylases (GAD67/65; GAD1/GAD2) are crucially involved in gamma-aminobutyric acid (GABA) synthesis and thus were repeatedly suggested to play an important role in the pathogenesis of anxiety disorders. In the present study, DNA methylation patterns in the GAD1 and GAD2 promoter and GAD1 intron 2 regions were investigated for association with panic disorder, with particular attention to possible effects of environmental factors. Sixty-five patients with panic disorder (f=44, m=21) and 65 matched healthy controls were analyzed for DNA methylation status at 38 GAD1 promoter/intron2 and 10 GAD2 promoter CpG sites via direct sequencing of sodium bisulfate treated DNA extracted from blood cells. Recent positive and negative life events were ascertained. Patients and controls were genotyped for GAD1 rs3762556, rs3791878 and rs3762555, all of which are located in the analyzed promoter region. Patients with panic disorder exhibited significantly lower average GAD1 methylation than healthy controls (p<0.001), particularly at three CpG sites in the promoter as well as in intron 2. The occurrence of negative life events was correlated with relatively decreased average methylation mainly in the female subsample (p=0.01). GAD1 SNP rs3762555 conferred a significantly lower methylation at three GAD1 intron 2 CpG sites (p<0.001). No differential methylation was observed in the GAD2 gene. The present pilot data suggest a potentially compensatory role of GAD1 gene hypomethylation in panic disorder possibly mediating the influence of negative life events and depending on genetic variation. Future studies are warranted to replicate the present finding in independent samples, preferably in a longitudinal design.