Facing the fear--clinical and neural effects of cognitive behavioural and pharmacotherapy in panic disorder with agoraphobia

Neurocircuitry of Treatment in Anxiety Disorders

Background:

Methods:

Results:

Conclusions:

Decreased defensive reactivity to interoceptive threat after successful exposure-based psychotherapy in patients with panic disorder

Panic disorder (PD) is characterized by a dysfunctional defensive responding to panic-related body symptoms that is assumed to contribute to the persistence of panic symptomatology. The present study aimed at examining whether this dysfunctional defensive reactivity to panic-related body symptoms would no longer be present following successful cognitive behavior therapy (CBT) but would persist when patients show insufficient symptom improvement. Therefore, in the present study, effects of CBT on reported symptoms and defensive response mobilization during interoceptive challenge were investigated using hyperventilation as a respiratory symptom provocation procedure. Changes in defensive mobilization to body symptoms in the course of CBT were investigated in patients with a primary diagnosis of PD with or without agoraphobia by applying a highly standardized hyperventilation task prior to and after a manual-based CBT (n = 38) or a waiting period (wait-list controls: n = 20). Defensive activation was indexed by the potentiation of the amygdala-dependent startle eyeblink response. All patients showed a pronounced defensive response mobilization to body symptoms at baseline. After treatment, no startle reflex potentiation was found in those patients who showed a clinically significant improvement. However, wait-list controls and treatment non-responders continued to show increased defensive responses to actually innocuous body symptoms after the treatment/waiting period. The present results indicate that the elimination of defensive reactivity to actually innocuous body symptoms might be a neurobiological correlate and indicator of successful CBT in patients with PD, which may help to monitor and optimize CBT outcomes.

Biomarkers in Panic Disorder

Background:

Panic disorder (PD) is a kind of anxiety disorder that impacts the life quality and functional perspectives in patients. However, the pathophysiological study of PD seems still inadequate and many unresolved issues need to be clarified.

Objectives:

In this review article of biomarkers in PD, the investigator will focus on the findings of magnetic resonance imaging (MRI) of the brain in the pathophysiology study. The MRI biomarkers would be divided into several categories, on the basis of structural and functional perspectives.

Methods:

The structural category would include the gray matter and white matter tract studies. The functional category would consist of functional MRI (fMRI), resting-state fMRI (Rs-fMRI), and magnetic resonance spectroscopy (MRS). The PD biomarkers revealed by the above methodologies would be discussed in this article.

Results:

For the gray matter perspectives, the PD patients would have alterations in the volumes of fear network structures, such as the amygdala, parahippocampal gyrus, thalamus, anterior cingulate cortex, insula, and frontal regions. For the white matter tract studies, the PD patients seemed to have alterations in the fasciculus linking the fear network regions, such as the anterior thalamic radiation, uncinate fasciculus, fronto-occipital fasciculus, and superior longitudinal fasciculus. For the fMRI studies in PD, the significant results also focused on the fear network regions, such as the amygdala, hippocampus, thalamus, insula, and frontal regions. For the Rs-fMRI studies, PD patients seemed to have alterations in the regions of the default mode network and fear network model. At last, the MRS results showed alterations in neuron metabolites of the hippocampus, amygdala, occipital cortex, and frontal regions.

Conclusion:

The MRI biomarkers in PD might be compatible with the extended fear network model hypothesis in PD, which included the amygdala, hippocampus, thalamus, insula, frontal regions, and sensory-related cortex.

Effect of CBT on Biased Semantic Network in Panic Disorder: A Multicenter fMRI Study Using Semantic Priming

OBJECTIVE

Cognitive-behavioral therapy (CBT) has been hypothesized to act by reducing the pathologically enhanced semantic, anxiety-related associations of patients with panic disorder. This study investigated the effects of CBT on the behavioral and neural correlates of the panic-related semantic network in patients with panic disorder.

METHODS

An automatic semantic priming paradigm specifically tailored for panic disorder, in which panic symptoms (e.g., "dizziness") were primed by panic triggers (e.g., "elevator") compared with neutral words (e.g., "bottle"), was performed during functional MRI scanning with 118 patients with panic disorder (compared with 150 healthy control subjects) before and 42 patients (compared with 52 healthy control subjects) after an exposure-based CBT. Neural correlates were investigated by comparing 103 pairs of matched patients and control subjects at the baseline (for patients) or T1 (for control subjects) assessment and 39 pairs at the posttreatment or T2 assessment.

RESULTS

At baseline or T1, patients rated panic-trigger/panic-symptom word pairs with higher relatedness and higher negative valence compared with healthy control subjects. Patients made faster lexical decisions to the panic-symptom words when they were preceded by panic-trigger words. This panic-priming effect in patients (compared with control subjects) was reflected in suppressed neural activation in the left and right temporal cortices and insulae and enhanced activation in the posterior and anterior cingulate cortices. After CBT, significant clinical improvements in the patient group were observed along with a reduction in relatedness and negative valence rating and attenuation of neural activation in the anterior cingulate cortex for processing of panic-trigger/panic-symptom word pairs.

CONCLUSIONS

The findings support a biased semantic network in panic disorder, which is normalized after CBT. Attenuation of anterior cingulate cortex activation for processing of panic-related associations provides a potential mechanism for future therapeutic interventions.

Association of NPSR1 gene variation and neural activity in patients with panic disorder and agoraphobia and healthy controls

INTRODUCTION

The neurobiological mechanisms behind panic disorder with agoraphobia (PD/AG) are not completely explored. The functional A/T single nucleotide polymorphism (SNP) rs324981 in the neuropeptide S receptor gene (NPSR1) has repeatedly been associated with panic disorder and might partly drive function respectively dysfunction of the neural "fear network". We aimed to investigate whether the NPSR1 T risk allele was associated with malfunctioning in a fronto-limbic network during the anticipation and perception of agoraphobia-specific stimuli.

METHOD

121 patients with PD/AG and 77 healthy controls (HC) underwent functional magnetic resonance imaging (fMRI) using the disorder specific "Westphal-Paradigm". It consists of neutral and agoraphobia-specific pictures, half of the pictures were cued to induce anticipatory anxiety.

RESULTS

Risk allele carriers showed significantly higher amygdala activation during the perception of agoraphobia-specific stimuli than A/A homozygotes. A linear group x genotype interaction during the perception of agoraphobia-specific stimuli showed a strong trend towards significance. Patients with the one or two T alleles displayed the highest and HC with the A/A genotype the lowest activation in the inferior orbitofrontal cortex (iOFC).

DISCUSSION

The study demonstrates an association of the NPSR1rs324981 genotype and the perception of agoraphobia-specific stimuli. These results support the assumption of a fronto-limbic dysfunction as an intermediate phenotype of PD/AG.

Cognitive-behavioral therapy effects on alerting network activity and effective connectivity in panic disorder

Given the particular relevance of arousal and alerting in panic disorder (PD), here the alerting network was investigated (1) contrasting patients with PD and healthy controls, (2) as a function of anxiety sensitivity constituting a dimensional measure of panic-related anxiety, and (3) as a possible correlate of treatment response. Using functional magnetic resonance imaging (fMRI), 45 out-patients with PD (f = 34) and 51 matched healthy controls were investigated for brain activation patterns and effective connectivity (Dynamic Causal Modeling, DCM) while performing the Attention Network Task (ANT). Anxiety sensitivity was ascertained by the Anxiety Sensitivity Index (ASI). Forty patients and 48 controls were re-scanned after a 6 weeks cognitive-behavioral treatment (CBT) or an equivalent waiting time, respectively. In the alerting condition, patients showed decreased activation in fronto-parietal pathways including the middle frontal gyrus and the superior parietal lobule (MFG, SPL). In addition, ASI scores were negatively correlated with connectivity emerging from the SPL, the SFB and the LC and going to the MFG in patients but not in healthy controls. CBT resulted in an increase in middle frontal and parietal activation along with increased connectivity going from the MFG to the SPL. This change in connectivity was positively correlated with reduction in ASI scores. There were no changes in controls. The present findings point to a pathological disintegration of the MFG in a fronto-parietal pathway in the alerting network in PD which was observed to be reversible by a successful CBT intervention.

Neuroimaging findings as predictors of treatment outcome of psychotherapy in anxiety disorders

Anxiety disorders are the largest group of mental disorders and a leading cause of impairment, implicating in high costs for health systems and society. Effective pharmacological and psychological treatments are available, but a significant fraction of these patients does not respond adequately to these treatments. The objective of this study is to identify neuroimaging findings that could predict response to psychotherapy in anxiety disorders.

METHODS

The authors reviewed psychotherapy clinical trials with neuroimaging conducted with patients with anxiety disorders. A systematic review was performed in MEDLINE database through PubMed, the Cochrane Collaboration's Clinical Trials Register (CENTRAL), PsycINFO and Thomson Reuters's Web of Science.

RESULTS

From the studies included in this review, 24 investigated anxiety disorder patients, and findings in the amygdala, dorsolateral prefrontal cortex (dlPFC), anterior cingulate cortex (ACC) and insula predicted response to psychotherapy in social anxiety disorder. Findings in ACC, hippocampus, insula, dlPFC, amygdala and inferior frontal gyrus (iFG) predicted response to psychotherapy in panic disorder and generalized anxiety disorder.

LIMITATIONS

There was great heterogeneity between the included studies regarding neuroimaging techniques and the tasks performed during functional neuroimaging.

CONCLUSION

Neuroimaging studies suggest that abnormalities in hippocampus, amygdala, iFG, uncus and areas linked with emotional regulation (dlPFC and ACC), predict a good outcome to psychotherapy in anxiety disorders.

[Cancer: Communicating the diagnosis and prognosis]

The diagnoses and prognoses that medical professionals have to communicate in cases of cancer come with special problems. Of all fatal diseases, cancer possibly causes most psychological impact on the patient. Although, by nature, medical professionals are aware of this negative impact and take care to be as prudent and human as possible, recent studies have shown that the "psychological factors of the patient" are of direct relevance to the medical factors in cancer, over and above their importance on quality of life during the course of the disease. This direct relevance needs replies that go beyond purely medical knowledge, as well as a specific training as to their application. Interdisciplinary medical-psychological cooperation is probably required. Studies indicate that compliance with both requisites may bring an improvement to clinical results. In Europe, although less than in the United States of America, the necessary inclusion has been the recognition of psychological training in academic pre- and postgraduate training in communicating these cases.

Patients' characteristics and their influence on course of fear during agoraphobic symptom provocation: may SS(N)RI treatment compensate unfavorable individual preconditions?

BACKGROUND

Patients' characteristics and antidepressants are discussed to be relevant in the context of phobic exposure.

AIMS

To identify patients characteristics associated with a differential course of fear during disorder-specific symptom provocation as well as to elucidate the effect of selective serotonin-(noradrenalin-) reuptake inhibitors [SS(N)RI] on development of fear in the context of re-exposure to the phobic stimuli.

METHODS

Twenty-eight clinically well-characterized patients with panic disorder and agoraphobia (PD/AG) were classified into subjects who show a reduction of fear ('Fear-') during a symptom provocation via a picture-based paradigm (T1) and those who did not ('Fear+'). Subsequently, SS(N)RI treatment was administered to all patients and subjects were re-exposed to the feared stimuli after 8 weeks of treatment (T2). Moreover, brain activity within the 'fear network' was measured via functional magnetic resonance imaging (fMRI) at T1 and T2.

RESULTS

Fear - were significantly younger and demonstrated increased exposure-related fear as well as stronger activity in several fear-related brain areas than Fear+. We found significant improvements in all clinical parameters after pharmacological intervention for the whole sample (T1-T2; all measures p < .02). However, reduction of fear as well as activation in (para)limbic structures during symptom provocation were now attenuated in Fear - but increased in Fear+.

CONCLUSIONS

Advanced age may predict a therapeutically unfavorable course of fear during agoraphobic symptom provocation. Since we found no negative impact of medication on fear development at all, there was some evidence that SS(N)RI treatment might improve the individual ability to get involved with the agoraphobic stimuli while conducting disorder-specific exposure.

Procrastination and anxiety: Exploring the contributions of multiple anxiety-related disorders

Background

Procrastination is the unnecessary delay of a task that subsequently creates anxiety (Rothblum, Solomon, & Maurakami, 1986). Research suggests that procrastination is linked with poorer mental health, but questions remain regarding its association with anxiety disorders. Studies exploring obsessive-compulsive disorder (OCD) and procrastination have found high levels of procrastination in OCD (Ferrari & McCown, 1994), but have also found no association between obsessive thoughts and procrastination (Kağan, Çakır, İlhan, & Kandemir, 2010). Scher and Osterman (2002) found that procrastination correlated with physiological anxiety and social anxiety, but not worry. No previous research has examined the connection between procrastination and health anxiety.

Participants and procedure

A non-clinical university sample (N = 300) completed online self-report questionnaires in order to examine the relationships between procrastination and symptoms of OCD, generalised anxiety disorder, social anxiety disorder, health anxiety, and panic disorder.

Results

Symptoms of panic disorder, social anxiety disorder, and health anxiety correlated with levels of procrastination. However, using a multiple regression analysis, only panic disorder symptoms uniquely predicted procrastination.

Conclusions

It is proposed that people with panic disorder may procrastinate to avoid anxiety inducing situations, or that individuals who frequently procrastinate may become sensitive to the anxiety caused by procrastination, thereby potentially triggering panic disorder. The full implications of these findings are further discussed.

Imaging and Genetic Approaches to Inform Biomarkers for Anxiety Disorders, Obsessive-Compulsive Disorders, and PSTD

Anxiety disorders are the most common mental health problem in the world and also claim the highest health care cost among various neuropsychiatric disorders. Anxiety disorders have a chronic and recurrent course and cause significantly negative impacts on patients' social, personal, and occupational functioning as well as quality of life. Despite their high prevalence rates, anxiety disorders have often been under-diagnosed or misdiagnosed, and consequently under-treated. Even with the correct diagnosis, anxiety disorders are known to be difficult to treat successfully. In order to implement better strategies in diagnosis, prognosis, treatment decision, and early prevention for anxiety disorders, tremendous efforts have been put into studies using genetic and neuroimaging techniques to advance our understandings of the underlying biological mechanisms. In addition to anxiety disorders including panic disorder, generalised anxiety disorder (GAD), specific phobias, social anxiety disorders (SAD), due to overlapping symptom dimensions, obsessive-compulsive disorder (OCD), and post-traumatic stress disorder (PTSD) (which were removed from the anxiety disorder category in DSM-5 to become separate categories) are also included for review of relevant genetic and neuroimaging findings. Although the number of genetic or neuroimaging studies focusing on anxiety disorders is relatively small compare to other psychiatric disorders such as psychotic disorders or mood disorders, various structural abnormalities in the grey or white matter, functional alterations of activity during resting-state or task conditions, molecular changes of neurotransmitter receptors or transporters, and genetic associations have all been reported. With continuing effort, further genetic and neuroimaging research may potentially lead to clinically useful biomarkers for the prevention, diagnosis, and management of these disorders.

Functional neuroanatomy in panic disorder: Status quo of the research

AIM

To provide an overview of the current research in the functional neuroanatomy of panic disorder.

METHODS

Panic disorder (PD) is a frequent psychiatric disease. Gorman et al (1989; 2000) proposed a comprehensive neuroanatomical model of PD, which suggested that fear- and anxiety-related responses are mediated by a so-called “fear network” which is centered in the amygdala and includes the hippocampus, thalamus, hypothalamus, periaqueductal gray region, locus coeruleus and other brainstem sites. We performed a systematic search by the electronic database PubMed. Thereby, the main focus was laid on recent neurofunctional, neurostructural, and neurochemical studies (from the period between January 2012 and April 2016). Within this frame, special attention was given to the emerging field of imaging genetics.

RESULTS

We noted that many neuroimaging studies have reinforced the role of the “fear network” regions in the pathophysiology of panic disorder. However, recent functional studies suggest abnormal activation mainly in an extended fear network comprising brainstem, anterior and midcingulate cortex (ACC and MCC), insula, and lateral as well as medial parts of the prefrontal cortex. Interestingly, differences in the amygdala activation were not as consistently reported as one would predict from the hypothesis of Gorman et al (2000). Indeed, amygdala hyperactivation seems to strongly depend on stimuli and experimental paradigms, sample heterogeneity and size, as well as on limitations of neuroimaging techniques. Advanced neurochemical studies have substantiated the major role of serotonergic, noradrenergic and glutamatergic neurotransmission in the pathophysiology of PD. However, alterations of GABAergic function in PD are still a matter of debate and also their specificity remains questionable. A promising new research approach is “imaging genetics”. Imaging genetic studies are designed to evaluate the impact of genetic variations (polymorphisms) on cerebral function in regions critical for PD. Most recently, imaging genetic studies have not only confirmed the importance of serotonergic and noradrenergic transmission in the etiology of PD but also indicated the significance of neuropeptide S receptor, CRH receptor, human TransMEMbrane protein (TMEM123D), and amiloride-sensitive cation channel 2 (ACCN2) genes.

CONCLUSION

In light of these findings it is conceivable that in the near future this research will lead to the development of clinically useful tools like predictive biomarkers or novel treatment options.