Genetic and environmental influences on relationship between anxiety sensitivity and anxiety subscales in children

Trauma in childhood is associated with greater pain catastrophizing but not anxiety sensitivity: a cross-sectional study

Introduction

Adverse life experiences have been identified as a possible vulnerability factor for chronic pain. This association could result from the effect of trauma on the psychological state of individuals. Previous studies found childhood trauma to be associated with pain catastrophizing and anxiety sensitivity, both of which have been associated with an increased risk of chronic pain. However, it is unknown whether trauma in adulthood affects these variables and whether the effect on pain catastrophizing is independent of confounds such as depression and anxiety.

Objectives

To test the effect of childhood and adulthood trauma on pain catastrophizing and anxiety sensitivity whilst controlling for depression and anxiety.

Methods

In the current study, we conducted an online survey in the United Kingdom in a chronic pain sample (N = 138; 123 women; age range 19-78). We analysed whether there is an association between different types of trauma (both in childhood and through the lifespan), pain catastrophizing, and anxiety sensitivity while controlling for anxiety and depression.

Results

We found that childhood trauma (particularly emotional abuse) significantly predicts pain catastrophizing, even when controlling for depression and anxiety, whereas it did not have a significant effect on anxiety sensitivity. Trauma through the lifespan (not childhood) did not have a significant effect on anxiety sensitivity nor did it have a significant effect on pain catastrophizing.

Conclusions

Our results show that the life stage in which trauma occurs is key in its psychological effects on patients with chronic pain. Furthermore, it shows that trauma affects some psychological variables but not others.

The cognitive anxiety sensitivity treatment (CAST) in anxiety prevention - Focus on separation anxiety and interoception

Given the high prevalence and considerable clinical and societal burden of anxiety disorders, preventive measures are urgently warranted to reduce their incidence and overall healthcare impact. Anxiety sensitivity (AS) - a key element in learning theories of anxiety disorders in the context of interoceptive conditioning - constitutes a malleable risk factor of particularly panic disorder and separation anxiety, which share developmental, nosological, epidemiological and pathomechanistic characteristics. The computer-assisted 'Cognitive Anxiety Sensitivity Treatment' (CAST) targeting interoceptive anxiety symptoms (cf. Schmidt et al., 2014) was translated, intensified and culturally adapted to German and evaluated in a sample of 105 healthy adult volunteers with elevated AS (mean ASI-3: 29.5) applying a randomized design. Success of the intervention was measured as a function of AS and separation anxiety (ASA-27) ∼6 weeks (T1) and ∼6 months (T2) after the intervention. As compared to waitlist, CAST resulted in a significant reduction of AS at both T1 and T2. Separation anxiety was not directly reduced by the intervention, but decreased mediated by a decline in AS. A composite interoceptive score capturing changes in sensitivity to respiratory symptoms during the baseline therapist-accompanied CAST session was shown to be predictive of overall response at T1. In sum, CAST-German Version was successfully established as an effective intervention reducing AS, while at the same time indirectly decreasing separation anxiety. A composite interoceptive score predicting treatment response might aid in further delineating risk markers informing targeted preventive interventions for anxiety disorders.

Factors associated with anxiety disorders among patients with substance use disorders in Lebanon: Results of a cross-sectional study

OBJECTIVES

Estimate the rate of anxiety disorders (AD) and associated factors among patients with substance use disorder (SUD) in Lebanon.

METHODS

A cross-sectional study, conducted between April and September 2017, enrolled 57 inpatients with SUD.

RESULTS

The rate of AD in patients with SUD was 61.4%. The university level of education compared to the primary level of education (ORa = 0.221) was significantly associated with lower anxiety among patients with SUD. Being sexually abused and having a family history of depression tended to significance.

PRACTICAL IMPLICATIONS

AD is widespread in Lebanon and high rates of anxiety in patients with SUD were found, warranting the implementation of strategic interventions and establishing national policies and legislation for mental health services to provide optimal care.

Reciprocal links between anxiety sensitivity and obsessive-compulsive symptoms in youth: a longitudinal twin study

BACKGROUND

Anxiety sensitivity, the tendency to fear the symptoms of anxiety, is a key risk factor for the development anxiety disorders. Although obsessive-compulsive disorder was previously classified as an anxiety disorder, the prospective relationship between anxiety sensitivity and obsessive-compulsive symptoms (OCS) has been largely overlooked. Furthermore, a lack of genetically informative studies means the aetiology of the link between anxiety sensitivity and OCS remains unclear.

METHODS

Adolescent twins and siblings (N = 1,579) from the G1219 study completed self-report questionnaires two years apart assessing anxiety sensitivity, OCS, anxiety and depression. Linear regression models tested prospective associations between anxiety sensitivity and OCS, with and without adjustment for anxiety and depressive symptoms. A phenotypic cross-lagged model assessed bidirectional influences between anxiety sensitivity and OCS over time, and a genetic version of this model examined the aetiology of these associations.

RESULTS

Anxiety sensitivity was prospectively associated with changes in OCS, even after controlling for comorbid anxiety and depressive symptoms. The longitudinal relationship between anxiety sensitivity and OCS was bidirectional, and these associations were predominantly accounted for by nonshared environmental influences.

CONCLUSIONS

Our findings are consistent with the notion that anxiety sensitivity is a risk factor for OCS during adolescence, but also suggest that experiencing OCS confers risk for heightened anxiety sensitivity. The reciprocal links between OCS and anxiety sensitivity over time are likely to be largely mediated by nonshared environmental experiences, as opposed to common genes. Our findings raise the possibility that interventions aimed at ameliorating anxiety sensitivity could reduce risk for OCS, and vice versa.

Genetic and environmental risk structure of internalizing psychopathology in youth

BACKGROUND

Internalizing disorders (IDs), consisting of syndromes of anxiety and depression, are common, debilitating conditions often beginning early in life. Various trait-like psychological constructs are associated with IDs. Our prior analysis identified a tripartite model of Fear/Anxiety, Dysphoria, and Positive Affect among symptoms of anxiety and depression and the following constructs in youth: anxiety sensitivity, fearfulness, behavioral activation and inhibition, irritability, neuroticism, and extraversion. The current study sought to elucidate their overarching latent genetic and environmental risk structure.

METHODS

The sample consisted of 768 juvenile twin subjects ages 9-14 assessed for the nine, abovementioned measures. We compared two multivariate twin models of this broad array of phenotypes.

RESULTS

A hypothesis-driven, common pathway twin model reflecting the tripartite structure of the measures were fit to these data. However, an alternative independent pathway model provided both a better fit and more nuanced insights into their underlying genetic and environmental risk factors.

CONCLUSIONS

Our findings suggest a complex latent genetic and environmental structure to ID phenotypes in youth. This structure, which incorporates both clinical symptoms and various psychological traits, informs future phenotypic approaches for identifying specific genetic and pathophysiological mechanisms underlying ID risk.

A neurobiological framework of separation anxiety and related phenotypes

In the DSM-5, separation anxiety disorder (SAD) is newly classified in the chapter on anxiety, renewing research efforts into its etiology. In this narrative review, we summarize the current literature on the genetic, endocrine, physiological, neural and neuropsychological underpinnings of SAD per se, SAD in the context of panic disorder, separation anxiety symptoms, and related intermediate phenotypes. SAD aggregates in families and has a heritability of ~43%. Variants in the oxytocin receptor, serotonin transporter, opioid receptor µ1, dopamine D4 receptor and translocator protein genes have all been associated with SAD. Dysregulation of the hypothalamus-pituitary-adrenal axis, dysfunctional cortico-limbic interaction and biased cognitive processing seem to constitute further neurobiological markers of separation anxiety. Hypersensitivity to carbon dioxide appears to be an endophenotype shared by SAD, panic disorder and anxiety sensitivity. The identification of biological risk markers and its multi-level integration hold great promise regarding the prediction of SAD risk, maintenance and course, and in the future may allow for the selection of indicated preventive and innovative, personalized therapeutic interventions.

Anxiety sensitivity in relation to cigarette smoking and other substance use in African American smokers

Anxiety sensitivity (AS)-fearfulness of anxiety symptoms-has been implicated in the etiology of emotional disorders (e.g., depressive and anxiety disorders) and linked to cigarette smoking and other substance use (SU). However, studies examining AS in relation to SU primarily have been conducted with racially/ethnically heterogeneous or mostly European American samples. Hence, this cross-sectional study involving secondary analysis of baseline data focused on investigating associations of AS with cigarette smoking and other SU in a sample of 630 non-treatment-seeking African American smokers (37.3% female; M age = 49.6 years; M cigarettes smoked per day = 15.4). After screening out individuals with non-nicotine substance dependence, participants reported their demographics, AS, dysphoria symptoms (i.e., depression and anxiety symptoms), and SU. In regression analyses controlling for dysphoria symptoms, age, education level, income level, and years of regular smoking, AS was positively associated with tobacco withdrawal severity (β = .12, p = .007), overall smoking motives (β = .17, p < .001), alcohol use problems (β = .12, p = .005), and other (non-nicotine, nonalcohol) SU problems (β = .16, p < .001). Though lacking the passage of time between assessments needed to provide strong evidence of mediation, unplanned analyses further revealed indirect associations of AS with several SU variables through dysphoria symptoms. Current findings are consistent with those found in prior samples and suggest that AS is similarly related to SU in African Americans, who may benefit from interventions that have been helpful in improving AS, dysphoria symptoms, and SU in other groups. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Risk Factors and Prevention Strategies for Anxiety Disorders in Childhood and Adolescence

Anxiety is prevalent in childhood and adolescence. Youth with maladaptive responses to common situations and stressors are at risk of having anxiety disorders. Persistent anxiety symptoms and anxiety disorders can be debilitating with long-term adverse outcomes in adulthood. Hence, decreasing the burden of anxiety disorders is an important public health priority. Development of anxiety disorders has a multifactorial etiology. There is a considerable complex interaction of genetics, temperament, parenting behavior, environmental triggers, and physiologic factors. Identification of these risk factors is key to early detection, prevention, and development of applicable management approaches. Despite several evidence-based treatments published, there are limited prevention strategies available. Effective implementation of prevention strategies is essential and can be achieved by either elimination or reduction of the negative risk factors or strengthening the protective factors on anxiety symptoms and anxiety disorders. This chapter reviews the common risk and protective factors and provides current literature on prevention strategies for pediatric and adolescent anxiety disorders.

Indirect Associations of Anxiety Sensitivity with Tobacco, Alcohol, and Other Drug Use Problems Through Emotional Disorder Symptoms in Adolescents

Theoretically, anxiety sensitivity-fear of anxiety symptoms-enhances perception of and emotional reactivity to autonomic arousal and mental distress, thereby increasing negative affect and motivation to use substances for negative reinforcement. Because no prior study of adolescents has tested if anxiety sensitivity is indirectly associated with substance use problems through symptoms of emotional disorders (i.e., disorders involving high levels of negative affect), the current cross-sectional study examined this theoretical pathway. Participants included ninth-grade students from 10 different high schools in the Los Angeles metropolitan area (N = 3005; 54.3% female). Self-report measures of anxiety sensitivity, emotional disorder symptoms, tobacco dependence, and alcohol and other drug problems were administered. Controlling for sex, race/ethnicity, parental education, school, and impulsiveness, we tested the associations of anxiety sensitivity with tobacco, alcohol, and other drug use problems as well as the indirect effects of anxiety sensitivity on each domain of substance use problems through emotional disorder symptoms. Anxiety sensitivity was associated with more severe tobacco dependence and greater alcohol problems and other drug problems, and anxiety sensitivity further was indirectly associated with all three domains of substance use problems through emotional disorder symptoms. Current findings suggest that adolescents high in anxiety sensitivity tend to experience emotional disorder symptoms, which may increase risk for substance use problems. Interventions that target anxiety sensitivity and enhance negative-affect coping skills may assist in preventing and reducing adolescent substance use problems.

Please Don't Leave Me-Separation Anxiety and Related Traits in Borderline Personality Disorder

PURPOSE OF REVIEW

In light of the apparent symptomatic resemblance of separation anxiety disorder (SAD) symptoms on the one hand and abandonment fears, anxiousness, and separation insecurity central to borderline personality disorder (BPD) on the other hand, a comprehensive overview of separation anxiety and related traits in BPD is provided.

RECENT FINDINGS

Epidemiological, environmental, psychological, and neurobiological data connecting BPD to separation events, feelings of loneliness, insecure attachment styles, dimensional separation anxiety as well as SAD per se suggest a partly shared etiological pathway model underlying BPD and SAD. Differential diagnostic aspects and implications for treatment are discussed, highlighting separation anxiety as a promising transdiagnostic target for specific psychotherapeutic and pharmacological treatment approaches in BPD. This innovative angle on cross-disorder symptomatology might carry potential for novel preventive and therapeutic avenues in clinical practice by guiding the development of interventions specifically targeting separation anxiety and attachment-related issues in BPD.

Anxiety sensitivity components in relation to alcohol and cannabis use, motives, and problems in treatment-seeking cigarette smokers

Anxiety sensitivity (AS)- fear of anxiety symptoms and their potential negative consequences-has been implicated in the development of substance use problems and motivation to use substances for coping with distress, though the AS components (physical, cognitive, and social concerns) have not been studied extensively in relation to alcohol- and cannabis-related variables. In a cross-sectional design, self-report measures of AS and alcohol and cannabis use, motives, and problems were administered to 364 treatment-seeking cigarette smokers with a history of alcohol and cannabis use. In both adjusted and unadjusted analyses, linear regression models indicated that AS cognitive concerns are related to cannabis-use conformity motives, alcohol-use coping motives, and alcohol problems; AS physical and cognitive concerns are related to greater cannabis problems specifically in males; and AS social concerns are associated with greater social, coping, enhancement, and conformity drinking motives. AS cognitive and physical concerns were also related to greater alcohol and cannabis problems, respectively, in subsamples limited to 214 current alcohol users and 170 current cannabis users. Together with prior work, current findings suggest that it may be beneficial to focus more on addressing AS cognitive concerns in individuals with tobacco-alcohol problem comorbidity, whereas it may be beneficial to focus on addressing both AS physical and cognitive concerns in males with tobacco-cannabis problem comorbidity. In addition, cigarette smokers high in AS social concerns may benefit from relaxation training to lessen their social anxiety as well as behavioral activation to enhance their positive affect.

Latent structure of negative valence measures in childhood

BACKGROUND

Internalizing disorders (IDs), consisting of the syndromes of anxiety and depression, are common, debilitating conditions often having onsets in adolescence. Scientists have developed dimensional self-report instruments that assess putative negative valence system (NVS) trait-like constructs as complimentary phenotypes to clinical symptoms. These include various measures that index temperamental predispositions to IDs and correlate with neural substrates of fear, anxiety, and affective regulation. This study sought to elucidate the overarching structure of putative NVS traits and their relationship to early manifestations of ID symptomatology.

METHODS

The sample consisted of 768 juvenile twin subjects ages 9-13. Together with ID symptoms, extant validated instruments were chosen to assess a broad spectrum of NVS traits: anxiety sensitivity, irritability, fearfulness, behavioral activation and inhibition, and neuroticism and extraversion. Exploratory and confirmatory factor analyses (EFA/CFA) were used to investigate the latent structure of the associations among these different constructs and ID symptoms. Bifactor modeling in addition to standard correlated-factor analytic approaches were applied.

RESULTS

Factor analyses produced a primary tripartite solution comprising anxiety/fear, dysphoria, and positive affect among all these measures. Competing DSM-like correlated factors and an RDoC-like NVS bifactor structure provided similar fit to these data.

CONCLUSIONS

Our findings support the conceptual organization of a tripartite latent internalizing domain in developing children. This structure includes both clinical symptoms and a variety of self-report dimensional traits currently in use by investigators. These various constructs are, therefore, most informatively investigated using an inclusive, integrated approach.

Emotional Competence and Anxiety in Childhood and Adolescence: A Meta-Analytic Review

Anxiety is conceptualized as a state of negative emotional arousal that is accompanied by concern about future threat. The purpose of this meta-analytic review was to evaluate the evidence of associations between emotional competence and anxiety by examining how specific emotional competence domains (emotion recognition, emotion expression, emotion awareness, emotion understanding, acceptance of emotion, emotional self-efficacy, sympathetic/empathic responses to others' emotions, recognition of how emotion communication and self-presentation affect relationships, and emotion regulatory processes) relate to anxiety in childhood and adolescence. A total of 185 studies were included in a series of meta-analyses (N's ranged from 573 to 25,711). Results showed that anxious youth are less effective at expressing (r = -0.15) and understanding emotions (r = -0.20), less aware of (r = -0.28) and less accepting of their own emotions (r = -0.49), and report less emotional self-efficacy (r = -0.36). More anxious children use more support-seeking coping strategies (r = 0.07) and are more likely to use less adaptive coping strategies including avoidant coping (r = 0.18), externalizing (r = 0.18), and maladaptive cognitive coping (r = 0.34). Emotion acceptance and awareness, emotional self-efficacy, and maladaptive cognitive coping yielded the largest effect sizes. Some effects varied with children's age. The findings inform intervention and treatment programs of anxiety in youth and identify several areas for future research.

Serotonin transporter variants play a role in anxiety sensitivity in South African adolescents

OBJECTIVES

Anxiety sensitivity (AS) has predictive potential for the development of anxiety disorders. We investigated the role that gene-environment (G × E) interactions, focussing on childhood trauma (CT) and selected SLC6A4 variants, play in modulating levels of AS in a South African adolescent population.

METHODS

All adolescents (n = 951) completed measures for AS and CT. Six SLC6A4 polymorphisms were genotyped. G × E influences on AS levels were assessed using multiple linear regression models. Relevant confounders were included in all analyses.

RESULTS

Xhosa (n = 634) and Coloured (n = 317) participants were analysed independently of one another. The 5-HTTLPR-rs25531 L-G haplotype associated with reduced AS among Xhosa adolescents (P = 0.010). In addition, the rs1042173 CC-genotype protected against increased levels of AS in Xhosa participants who had experienced increased levels of CT (P = 0.038). Coloured males homozygous for the S-allele had significantly increased levels of AS compared to Coloured males with at least one L-allele (P = 0.016).

CONCLUSIONS

This is the first study to be conducted on AS in adolescents from two ethnically diverse populations. Results indicate that the L-G haplotype confers protection against high AS levels in a Xhosa population. Furthermore, increased CT was found to protect against high levels of AS in Xhosa rs1042173 CC-carriers.

Effect of trait anxiety on cognitive test performance in adolescents with and without attention-deficit/hyperactivity disorder

INTRODUCTION

Attention-deficit/hyperactivity disorder (ADHD) and anxiety are frequently comorbid disorders associated with different types of abnormal performance on neuropsychological tests. Although some studies have shown that comorbid anxiety alters ADHD test performance, results inconsistently show both improvements and worsening of different abilities, with failures to replicate across different anxiety disorders. Alternatively, trait anxiety may reflect a more stable influence on ADHD test performance than various diagnosable anxiety disorders.

METHOD

To better understand the possible enhancing or deleterious effects of anxiety on ADHD cognitive impairments, this study examined the effect of individual differences in trait anxiety measured by the Multidimensional Anxiety Scale for Children (MASC) on a battery of computerized, rapid-performance tests measuring attention and impulsivity-related performance in 98 Diagnostic and Statistical Manual of Mental Disorders-Fourth Edition (DSM-IV) Combined-Subtype ADHD adolescents and 123 healthy controls. It was hypothesized that trait anxiety would attenuate response inhibition and attention deficits in ADHD.

RESULTS

ADHD-diagnosed adolescents with higher trait anxiety performed better on indices of sustained attention, reaction time, and motor variability, and had altered overall test-performance strategy, while response inhibition was affected in both ADHD and non-ADHD.

CONCLUSIONS

This study provides the first evidence that pathological levels of anxiety are not needed to see differences in ADHD neuropsychological test performance. Instead, mildly elevated trait anxiety confers a protective influence by reducing the degree of impairment seen in ADHD. These findings suggest that better performing ADHD adolescents might have optimized levels of cortical arousal, and raise new questions about how best to identify the neurobiological substrates responsible for the beneficial effects.

Anxiety sensitivity is associated with attentional bias for pain-related information in healthy children and adolescents

This investigation explored the association between anxiety sensitivity and attentional bias for threatening information in children and adolescents ( N = 40). Participants completed a pictorial version of the visual-probe task, featuring pain-related, health-threat and general-threat images presented for 500 and 1250 ms. Regression analyses revealed significant associations between anxiety sensitivity and attentional bias towards pain-related images presented for 500 ms and between state anxiety and attentional bias towards general-threat images presented for 1250 ms. These results suggest that in children and adolescents, anxiety sensitivity is associated with attentional bias for negative information of personal relevance.

A longitudinal twin and sibling study of the hopelessness theory of depression in adolescence and young adulthood

BACKGROUND

Maladaptive cognitive biases such as negative attributional style and hopelessness have been implicated in the development and maintenance of depression. According to the hopelessness theory of depression, hopelessness mediates the association between attributional style and depression. The aetiological processes underpinning this influential theory remain unknown. The current study investigated genetic and environmental influences on hopelessness and its concurrent and longitudinal associations with attributional style and depression across adolescence and emerging adulthood. Furthermore, given high co-morbidity between depression and anxiety, the study investigated whether these maladaptive cognitions constitute transdiagnostic cognitive content common to both internalizing symptoms.

METHOD

A total of 2619 twins/siblings reported attributional style (mean age 15 and 17 years), hopelessness (mean age 17 years), and depression and anxiety symptoms (mean age 17 and 20 years).

RESULTS

Partial correlations revealed that attributional style and hopelessness were uniquely associated with depression but not anxiety symptoms. Hopelessness partially mediated the relationship between attributional style and depression. Hopelessness was moderately heritable (A = 0.37, 95% confidence interval 0.28-0.47), with remaining variance accounted for by non-shared environmental influences. Independent pathway models indicated that a set of common genetic influences largely accounted for the association between attributional style, hopelessness and depression symptoms, both concurrently and across development.

CONCLUSIONS

The results provide novel evidence that associations between attributional style, hopelessness and depression symptoms are largely due to shared genetic liability, suggesting developmentally stable biological pathways underpinning the hopelessness theory of depression. Both attributional style and hopelessness constituted unique cognitive content in depression. The results inform molecular genetics research and cognitive treatment approaches.

Parent- and child-driven effects during the transition to adolescence: a longitudinal, genetic analysis of the home environment

Theoretical models of child development typically consider the home environment as a product of bidirectional effects, with parent‐ and child‐driven processes operating interdependently. However, the developmental structure of these processes during the transition from childhood to adolescence has not been well studied. In this study we used longitudinal genetic analyses of data from 6646 UK‐representative twin pairs (aged 9–16 years) to investigate stability and change in parenting and household chaos in the context of parent–child bidirectional effects. Stability in the home environment was modest, arising mainly from parent‐driven processes and family‐wide influences. In contrast, change over time was more influenced by child‐driven processes, indicated by significant age‐specific genetic influences. Interpretations of these results and their implications for researchers are discussed.

Aetiological influences on stability and change in emotional and behavioural problems across development: a systematic review

Emotional and behavioural problems in childhood and adolescence can be chronic and are predictive of future psychiatric problems. Understanding what factors drive the development and maintenance of these problems is therefore crucial. Longitudinal behavioural genetic studies using twin, sibling or adoption data can be used to explore the developmental aetiology of stability and change in childhood and adolescent psychopathology. We present a systematic review of longitudinal, behavioural genetic analyses of emotional and behavioural problems between ages 0 to 18 years. We identified 58 studies, of which 19 examined emotional problems, 30 examined behavioural problems, and 9 examined both. In the majority of studies, stability in emotional and behavioural problems was primarily genetically influenced. Stable environmental factors were also widely found, although these typically played a smaller role. Both genetic and environmental factors were involved in change across development. We discuss the findings in the context of the wider developmental literature and make recommendations for future research.

The stability and change of etiological influences on depression, anxiety symptoms and their co-occurrence across adolescence and young adulthood

BACKGROUND

Depression and anxiety persist within and across diagnostic boundaries. The manner in which common v. disorder-specific genetic and environmental influences operate across development to maintain internalizing disorders and their co-morbidity is unclear. This paper investigates the stability and change of etiological influences on depression, panic, generalized, separation and social anxiety symptoms, and their co-occurrence, across adolescence and young adulthood.

METHOD

A total of 2619 twins/siblings prospectively reported symptoms of depression and anxiety at mean ages 15, 17 and 20 years.

RESULTS

Each symptom scale showed a similar pattern of moderate continuity across development, largely underpinned by genetic stability. New genetic influences contributing to change in the developmental course of the symptoms emerged at each time point. All symptom scales correlated moderately with one another over time. Genetic influences, both stable and time-specific, overlapped considerably between the scales. Non-shared environmental influences were largely time- and symptom-specific, but some contributed moderately to the stability of depression and anxiety symptom scales. These stable, longitudinal environmental influences were highly correlated between the symptoms.

CONCLUSIONS

The results highlight both stable and dynamic etiology of depression and anxiety symptom scales. They provide preliminary evidence that stable as well as newly emerging genes contribute to the co-morbidity between depression and anxiety across adolescence and young adulthood. Conversely, environmental influences are largely time-specific and contribute to change in symptoms over time. The results inform molecular genetics research and transdiagnostic treatment and prevention approaches.

Generalised Anxiety Disorder--A Twin Study of Genetic Architecture, Genome-Wide Association and Differential Gene Expression

Generalised Anxiety Disorder (GAD) is a common anxiety-related diagnosis, affecting approximately 5% of the adult population. One characteristic of GAD is a high degree of anxiety sensitivity (AS), a personality trait which describes the fear of arousal-related sensations. Here we present a genome-wide association study of AS using a cohort of 730 MZ and DZ female twins. The GWAS showed a significant association for a variant within the RBFOX1 gene. A heritability analysis of the same cohort also confirmed a significant genetic component with h2 of 0.42. Additionally, a subset of the cohort (25 MZ twins discordant for AS) was studied for evidence of differential expression using RNA-seq data. Significant differential expression of two exons with the ITM2B gene within the discordant MZ subset was observed, a finding that was replicated in an independent cohort. While previous research has shown that anxiety has a high comorbidity with a variety of psychiatric and neurodegenerative disorders, our analysis suggests a novel etiology specific to AS.

Anxiety sensitivity and the anticipation of predictable and unpredictable threat: Evidence from the startle response and event-related potentials

There is growing evidence that heightened sensitivity to unpredictable threat is a core mechanism of dysfunction in anxiety disorders. However, it is unclear whether anxiety sensitivity is also associated with sensitivity to unpredictable threat. In the present study, 131 participants completed the Anxiety Sensitivity Index-3, which includes physical concerns (PC), social concerns (SC), and cognitive concerns (CC) subscales, and a predictable vs. unpredictable threat-of-shock task. Startle eyeblink and ERP responses (N100, P300) to the acoustic startle probes were measured during the task. PC and CC were associated with heightened and attenuated, respectively, startle for the unpredictable (but not predictable) condition. CC were also associated with attenuated probe N100 for the unpredictable condition only, and PC were associated with increased P300 suppression across the predictable and unpredictable conditions. This study provides novel evidence that the different anxiety sensitivity dimensions demonstrate unique relationships with the RDoC domains "acute" and "potential" threat.

Cognitive content specificity in anxiety and depressive disorder symptoms: a twin study of cross-sectional associations with anxiety sensitivity dimensions across development

BACKGROUND

The classification of anxiety and depressive disorders has long been debated and has important clinical implications. The present study combined a genetically sensitive design and multiple time points to investigate cognitive content specificity in anxiety and depressive disorder symptoms across anxiety sensitivity dimensions, a cognitive distortion implicated in both disorders.

METHOD

Phenotypic and genetic correlations between anxiety sensitivity dimensions, anxiety and depressive disorder symptoms were examined at five waves of data collection within childhood, adolescence and early adulthood in two representative twin studies (n pairs = 300 and 1372).

RESULTS

The physical concerns dimension of anxiety sensitivity (fear of bodily symptoms) was significantly associated with anxiety but not depression at all waves. Genetic influences on physical concerns overlapped substantially more with anxiety than depression. Conversely, mental concerns (worry regarding cognitive control) were phenotypically more strongly associated with depression than anxiety. Social concerns (fear of publicly observable symptoms of anxiety) were associated with both anxiety and depression in adolescence. Genetic influences on mental and social concerns were shared to a similar extent with both anxiety and depression.

CONCLUSIONS

Phenotypic patterns of cognitive specificity and broader genetic associations between anxiety sensitivity dimensions, anxiety and depressive disorder symptoms were similar at all waves. Both disorder-specific and shared cognitive concerns were identified, suggesting it is appropriate to classify anxiety and depression as distinct but related disorders and confirming the clinical perspective that cognitive therapy is most likely to benefit by targeting cognitive concerns relating specifically to the individual's presenting symptoms across development.

Emotional reasoning and anxiety sensitivity: associations with social anxiety disorder in childhood

BACKGROUND

Two specific cognitive constructs that have been implicated in the development and maintenance of anxiety symptoms are anxiety sensitivity and emotional reasoning, both of which relate to the experience and meaning of physical symptoms of arousal or anxiety. The interpretation of physical symptoms has been particularly implicated in theories of social anxiety disorder, where internal physical symptoms are hypothesized to influence the individual's appraisals of the self as a social object.

METHOD

The current study compared 75 children on measures of anxiety sensitivity and emotional reasoning: 25 with social anxiety disorder, 25 with other anxiety disorders, and 25 nonanxious children (aged 7-12 years).

RESULTS

Children with social anxiety disorder reported higher levels of anxiety sensitivity and were more likely than both other groups to view ambiguous situations as anxiety provoking, whether physical information was present or not. There were no group differences in the extent to which physical information altered children's interpretation of hypothetical scenarios.

LIMITATIONS

This study is the first to investigate emotional reasoning in clinically anxious children and therefore replication is needed. In addition, those in both anxious groups commonly had comorbid conditions and, consequently, specific conclusions about social anxiety disorder need to be treated with caution.

CONCLUSION

The findings highlight cognitive characteristics that may be particularly pertinent in the context of social anxiety disorder in childhood and which may be potential targets for treatment. Furthermore, the findings suggest that strategies to modify these particular cognitive constructs may not be necessary in treatments of some other childhood anxiety disorders.