Neurochemical and genetic factors in panic disorder: a systematic review.

This systematic review addresses the complex nature of Panic Disorder (PD), characterized by recurrent episodes of acute fear, with a focus on updating and consolidating knowledge regarding neurochemical, genetic, and epigenetic factors associated with PD. Utilizing the PRISMA methodology, 33 original peer-reviewed studies were identified, comprising 6 studies related to human neurochemicals, 10 related to human genetic or epigenetic alterations, and 17 animal studies. The review reveals patterns of altered expression in various biological systems, including neurotransmission, the Hypothalamic-Pituitary-Adrenal (HPA) axis, neuroplasticity, and genetic and epigenetic factors leading to neuroanatomical modifications. Noteworthy findings include lower receptor binding of GABAA and serotonin neurotransmitters in the amygdala. The involvement of orexin (ORX) neurons in the dorsomedial/perifornical region in triggering panic reactions is highlighted, with systemic ORX-1 receptor antagonists blocking panic responses. Elevated Interleukin 6 and leptin levels in PD patients suggest potential connections between stress-induced inflammatory changes and PD. Brain-derived neurotrophic factor (BDNF) and tyrosine receptor kinase B (TrkB) signaling are implicated in panic-like responses, particularly in the dorsal periaqueductal gray (dPAG), where BDNF's panicolytic-like effects operate through GABAA-dependent mechanisms. GABAergic neurons' inhibitory influence on dorsomedial and posterior hypothalamus nuclei is identified, potentially reducing the excitability of neurons involved in panic-like responses. The dorsomedial hypothalamus (DMH) is highlighted as a specific hypothalamic nucleus relevant to the genesis and maintenance of panic disorder. Altered brain lactate and glutamate concentrations, along with identified genetic polymorphisms linked to PD, further contribute to the intricate neurochemical landscape associated with the disorder. The review underscores the potential impact of neurochemical, genetic, and epigenetic factors on the development and expression of PD. The comprehensive insights provided by this systematic review contribute to advancing our understanding of the multifaceted nature of Panic Disorder and pave the way for targeted therapeutic strategies.

Incidence of Panic Disorder Diagnoses After Celebrity Disclosures of Panic Disorder in South Korea.

Importance: The persistent stigma associated with mental health conditions is a major challenge worldwide. Celebrities may improve this by openly discussing their own mental health issues, potentially influencing public attitudes and encouraging individuals to seek treatment for these conditions. Objective: To evaluate the impact of celebrity mental health disclosures on the incidence and prevalence of panic disorder diagnosis in South Korea. Design, Setting, and Participants: This cohort study included the entire South Korean population from January 2004 to December 2021, as reflected in the National Health Insurance Service data. Analysis was conducted from May 2022 through January 2024. Exposure: Time periods analyzed included the timeframe before (from January 2004 to December 2010) and after the public disclosures of panic disorder by 3 high-profile Korean celebrities between December 2010 and January 2012 (from January 2011 to December 2021). Main Outcomes and Measures: Monthly incidence and prevalence of panic disorder, defined by the presence of a clinical diagnosis of the condition. Trends were assessed using interrupted time series analysis with autoregressive integrated moving average models. To assess public interest in panic disorder, trends in search data were analyzed, examining the association between the timing of increased searches and changes in the incidence and prevalence of panic disorder. Data on obsessive-compulsive disorder (OCD) were included as a control. Results: The study covered the entire population of South Korea, including 48 559 946 individuals in January 2004 and 52 593 886 individuals in December 2021. Before 2011, the mean (SD) annual prevalence of panic disorder was stable at 560 (140) persons per 100 000 persons per year. The celebrity disclosure in December 2010 was associated with higher monthly incidence rates of panic disorder, as measured by insurance claims data, changes that were observed in both the level (5.8 persons; 95% CI, 2.2-9.5 persons) and slope (0.78 persons per month; 95% CI, 0.19-1.40 persons per month) per 100 000 persons. By 2021, the observed annual prevalence per 100 000 persons reached 7530 persons, an increase of 775.6% compared with the 860 persons (95% CI, 330-1400 persons) estimated if the disclosures had not occurred. Internet searches anticipated changes in monthly prevalence with a lag of 2 or 3 months (F = 4.26, P = .02 and F = 3.11, P = .03, respectively). The celebrity disclosures had no significant association with the incidence or prevalence of OCD. Conclusions and Relevance: In this observational cohort study, celebrity disclosure of mental health conditions was associated with a sustained reduction in stigma, as reflected in increased help-seeking behavior for the condition over more than a decade. This underscores the influential role celebrities can play in shaping public health perceptions and behaviors, offering valuable insights for the development of future mental health policies and public awareness campaigns.

Locus coeruleus noradrenaline depletion and its differential impact on CO2-induced panic and hyperventilation in male and female mice.

CO2 exposure has been used to investigate the panicogenic response in patients with panic disorder. These patients are more sensitive to CO2, and more likely to experience the "false suffocation alarm" which triggers panic attacks. Imbalances in locus coeruleus noradrenergic (LC-NA) neurotransmission are responsible for psychiatric disorders, including panic disorder. These neurons are sensitive to changes in CO2/pH. Therefore, we investigated if LC-NA neurons are differentially activated after severe hypercapnia in mice. Further, we evaluated the participation of LC-NA neurons in ventilatory and panic-like escape responses induced by 20% CO2 in male and female wild type mice and two mouse models of altered LC-NA synthesis. Hypercapnia activates the LC-NA neurons, with males presenting a heightened level of activation. Mutant males lacking or with reduced LC-NA synthesis showed hypoventilation, while animals lacking LC noradrenaline present an increased metabolic rate compared to wild type in normocapnia. When exposed to CO2, males lacking LC noradrenaline showed a lower respiratory frequency compared to control animals. On the other hand, females lacking LC noradrenaline presented a higher tidal volume. Nevertheless, no change in ventilation was observed in either sex. CO2 evoked an active escape response. Mice lacking LC noradrenaline had a blunted jumping response and an increased freezing duration compared to the other groups. They also presented fewer racing episodes compared to wild type animals, but not different from mice with reduced LC noradrenaline. These findings suggest that LC-NA has an important role in ventilatory and panic-like escape responses elicited by CO2 exposure in mice.

Psychological distress and uterine fibroids: a bidirectional two-sample mendelian randomization study.

BACKGROUND: Observational data indicates a connection between emotional discomfort, such as anxiety and depression, and uterine fibroids (UFs). However, additional investigation is required to establish the causal relationship between them. Hence, we assessed the reciprocal causality between four psychological disorders and UFs utilizing two-sample Mendelian randomization (MR). METHODS: To evaluate the causal relationship between four types of psychological distress (depressive symptoms, severe depression, anxiety or panic attacks, mood swings) and UFs, bidirectional two-sample MR was employed, utilizing single nucleotide polymorphisms (SNPs) associated with these conditions. Both univariate MR (UVMR) and multivariate MR (MVMR) primarily applied inverse variance weighted (IVW) as the method for estimating potential causal effects. Complementary approaches such as MR Egger, weighted median, simple mode, and weighted mode were utilized to validate the findings. To assess the robustness of our MR results, we conducted sensitivity analyses using Cochran's Q-test and the MR Egger intercept test. RESULTS: The results of our UVMR analysis suggest that genetic predispositions to depressive symptoms (Odds Ratio [OR] = 1.563, 95% Confidence Interval [CI] = 1.209-2.021, P = 0.001) and major depressive disorder (MDD) (OR = 1.176, 95% CI = 1.044-1.324, P = 0.007) are associated with an increased risk of UFs. Moreover, the IVW model showed a nominally significant positive correlation between mood swings (OR: 1.578; 95% CI: 1.062-2.345; P = 0.024) and UFs risk. However, our analysis did not establish a causal relationship between UFs and the four types of psychological distress. Even after adjusting for confounders like body mass index (BMI), smoking, alcohol consumption, and number of live births in the MVMR, the causal link between MDD and UFs remained significant (OR = 1.217, 95% CI = 1.039-1.425, P = 0.015). CONCLUSIONS: Our study presents evidence supporting the causal relationship between genetic susceptibility to MDD and the incidence of UFs. These findings highlight the significance of addressing psychological health issues, particularly depression, in both the prevention and treatment of UFs.

Epigenetic signatures of social anxiety, panic disorders and stress experiences: Insights from genome-wide DNA methylation risk scores.

Social anxiety disorder (SAD) and panic disorder (PD) are prevalent anxiety disorders characterized by a complex interplay of genetic and environmental factors. Both disorders share overlapping features and often coexist, despite displaying distinct characteristics. Childhood life adversity, overall stressful life events, and genetic factors contribute to the development of these disorders. DNA methylation, an epigenetic modification, has been implicated in the pathogenesis of these diseases. In this study, we investigated whether whole-genome DNA methylation risk scores (MRSs) for SAD risk, severity of social anxiety, childhood life adversity, PD risk, and overall stressful life events were associated with SAD or PD case‒control status. Preliminary epigenome-wide association studies (EWASs) for SAD risk, severity of social anxiety, and childhood life adversity were conducted in 66 SAD individuals and 77 healthy controls (HCs). Similarly, EWASs for PD risk and overall stressful life events were performed in 182 PD individuals and 81 HCs. MRSs were calculated from these EWASs. MRSs derived from the EWASs of SAD risk and severity of social anxiety were greater in PD patients than in HCs. Additionally, MRSs derived from the EWASs of overall stressful life events, particularly in PD individuals, were lower in SAD individuals than in HCs. In contrast, MRSs for childhood life adversity or PD risk were not significantly associated with PD or SAD case‒control status. These findings highlight the epigenetic features shared in both disorders and the distinctive epigenetic features related to social avoidance in SAD patients, helping to elucidate the epigenetic basis of these disorders.

Cross-sectional study of psychiatric disorders in patients with chronic musculoskeletal pain and individuals without pain.

BACKGROUND: Musculoskeletal chronic pain is a leading cause of global disability and laboral incapacity. However, there is a lack of population-based studies that investigate the relationship between chronic pain and mental disorders with a control group, particularly among low- and middle-income countries. Chronic pain is a serious public health problem in terms of human suffering, and in terms of socioeconomic implications. Frequent association with different mental disorders increases disability, decreases quality of life, and makes diagnosis and treatment challenging. The present study aimed to evaluate the presence of mental disorders in patients with chronic musculoskeletal pain and compare with a control group without pain. METHODS: We selected 100 patients in a regular follow-up at the Musculoskeletal Pain Outpatient Clinic of the University Hospital and compared them with 100 painless individuals from the control group from June 2016 to June 2018. The instruments used were the Mini International Neuropsychiatric Interview (MINI-PLUS) and a structured questionnaire to collect sociodemographic data. Statistical analysis used t-test, chi-square, Fisher's exact test, Mann-Whitney, Kolmogorov-Smirnov tests, and multiple logistic regression. RESULTS: In the sample evaluated, the majority of patients were women (83%), of brown color (54%), with lower-level education (51%), lower salary range (73%) and high absenteeism rate at work (60,7%). Patients with chronic pain had more psychiatric disorders (88% vs. 48% in the control group; p < 0.001). The most frequent diagnoses were anxiety disorders with panic attacks (44%), generalized anxiety (36%), mixed anxiety and depression disorder (33%), social phobia (30%), agoraphobia (29%), suicide risk (28%), and major depression (27%). CONCLUSION: Positive correlations of mental disorders and chronic musculoskeletal pain have been documented. This suggests that psychiatric components must be taken into account in the management of chronic pain syndromes. The use of Mini Plus as a diagnostic tool for psychiatric disorders can contribute to optimizing the diagnosis and treatment of patients with chronic pain and encourage the creation of policies with strategies and criteria for quick access to Multi-professional Services.

Daily stress reactivity and risk appraisal mediates childhood parental abuse predicting adulthood psychopathology severity: An 18-year longitudinal mediation analysis.

Identifying mechanisms of childhood abuse-adulthood psychopathology relations could facilitate preventive efforts, but most prior studies used cross-sectional or two-wave designs and did not test the effects of childhood maternal and paternal abuse separately. Our 18-year three-wave study thus determined if Wave 2 daily stress reactivity and risk appraisal severity mediated Wave 1 retrospectively-reported childhood maternal and paternal abuse on Wave 3 generalized anxiety disorder (GAD), major depressive disorder (MDD), panic disorder (PD), alcohol (AUD), and substance use disorder (SUD) self-rated symptom severity. Longitudinal structural equation modeling was employed, adjusting for Wave 1 psychopathology severity. Higher childhood maternal and paternal abuse consistently predicted greater future daily stress reactivity and risk appraisal, and these mediators subsequently predicted increased GAD, MDD, and PD, but not AUD and SUD severity. Daily stress reactivity and risk appraisal consistently mediated the pathways between childhood maternal and paternal abuse predicting heightened adulthood GAD, MDD, and PD (Cohen's d = 0.333-0.888) but not AUD and SUD severity. Mediation effect sizes were stronger for childhood maternal (24.5-83.0%) than paternal (19.5-56.0%) abuse as the predictor. The latent interaction between Wave 1 childhood maternal and paternal abuse did not moderate the effect of Wave 1 maternal or paternal abuse on any Wave 3 adulthood psychopathology severity through Wave 2 daily stress reactivity and risk appraisal. Our research emphasizes the urgent requirement for continuous evaluation and intervention initiatives in trauma-informed care, both in inpatient and outpatient treatment settings.

Discrimination between healthy participants and people with panic disorder based on polygenic scores for psychiatric disorders and for intermediate phenotypes using machine learning.

OBJECTIVE: Panic disorder is a modestly heritable condition. Currently, diagnosis is based only on clinical symptoms; identifying objective biomarkers and a more reliable diagnostic procedure is desirable. We investigated whether people with panic disorder can be reliably diagnosed utilizing combinations of multiple polygenic scores for psychiatric disorders and their intermediate phenotypes, compared with single polygenic score approaches, by applying specific machine learning techniques. METHODS: Polygenic scores for 48 psychiatric disorders and intermediate phenotypes based on large-scale genome-wide association studies (n = 7556-1,131,881) were calculated for people with panic disorder (n = 718) and healthy controls (n = 1717). Discrimination between people with panic disorder and healthy controls was based on the 48 polygenic scores using five methods for classification: logistic regression, neural networks, quadratic discriminant analysis, random forests and a support vector machine. Differences in discrimination accuracy (area under the curve) due to an increased number of polygenic score combinations and differences in the accuracy across five classifiers were investigated. RESULTS: All five classifiers performed relatively well for distinguishing people with panic disorder from healthy controls by increasing the number of polygenic scores. Of the 48 polygenic scores, the polygenic score for anxiety UK Biobank was the most useful for discrimination by the classifiers. In combinations of two or three polygenic scores, the polygenic score for anxiety UK Biobank was included as one of polygenic scores in all classifiers. When all 48 polygenic scores were used in combination, the greatest areas under the curve significantly differed among the five classifiers. Support vector machine and logistic regression had higher accuracy than quadratic discriminant analysis and random forests. For each classifier, the greatest area under the curve was 0.600 ± 0.030 for logistic regression (polygenic score combinations N = 14), 0.591 ± 0.039 for neural networks (N = 9), 0.603 ± 0.033 for quadratic discriminant analysis (N = 10), 0.572 ± 0.039 for random forests (N = 25) and 0.617 ± 0.041 for support vector machine (N = 11). The greatest areas under the curve at the best polygenic score combination significantly differed among the five classifiers. Random forests had the lowest accuracy among classifiers. Support vector machine had higher accuracy than neural networks. CONCLUSIONS: These findings suggest that increasing the number of polygenic score combinations up to approximately 10 effectively improved the discrimination accuracy and that support vector machine exhibited greater accuracy among classifiers. However, the discrimination accuracy for panic disorder, when based solely on polygenic score combinations, was found to be modest.

Effects of antidepressant on FKBP51 mRNA expression and neuroendocrine hormones in patients with panic disorder.

OBJECTIVE: The purpose of this study was to investigate the effects of escitalopram on the peripheral expression of hypothalamic-pituitary-adrenal (HPA) axis-related genes (FKBP51, HSP90, NR3C1 and POMC) and HPA-axis hormones in patients with panic disorder (PD). METHODS: Seventy-seven patients with PD were treated with escitalopram for 12 weeks. All participants were assessed for the severity of panic symptoms using the Panic Disorder Severity Scale (PDSS). The expression of HPA-axis genes was measured using real-time quantitative fluorescent PCR, and ACTH and cortisol levels were measured using chemiluminescence at baseline and after 12 weeks of treatment. RESULTS: At baseline, patients with PD had elevated levels of ACTH and cortisol, and FKBP51 expression in comparison to healthy controls (all p < 0.01). Correlation analysis revealed that FKBP51 expression levels were significantly positively related to cortisol levels and the severity of PD (all p < 0.01). Furthermore, baseline ACTH and cortisol levels, and FKBP51 expression levels were significantly reduced after 12 weeks of treatment, and the change in the PDSS score from baseline to post-treatment was significantly and positively related to the change in cortisol (p < 0.01). CONCLUSIONS: The results suggest that PD may be associated with elevated levels of ACTH and cortisol, and FKBP51 expression, and that all three biomarkers are substantially decreased in patients who have received escitalopram treatment.

The Effectiveness of a Digital App for Reduction of Clinical Symptoms in Individuals With Panic Disorder: Randomized Controlled Trial.

BACKGROUND: Panic disorder is a common and important disease in clinical practice that decreases individual productivity and increases health care use. Treatments comprise medication and cognitive behavioral therapy. However, adverse medication effects and poor treatment compliance mean new therapeutic models are needed. OBJECTIVE: We hypothesized that digital therapy for panic disorder may improve panic disorder symptoms and that treatment response would be associated with brain activity changes assessed with functional near-infrared spectroscopy (fNIRS). METHODS: Individuals (n=50) with a history of panic attacks were recruited. Symptoms were assessed before and after the use of an app for panic disorder, which in this study was a smartphone-based app for treating the clinical symptoms of panic disorder, panic symptoms, depressive symptoms, and anxiety. The hemodynamics in the frontal cortex during the resting state were measured via fNIRS. The app had 4 parts: diary, education, quest, and serious games. The study trial was approved by the institutional review board of Chung-Ang University Hospital (1041078-202112-HR-349-01) and written informed consent was obtained from all participants. RESULTS: The number of participants with improved panic symptoms in the app use group (20/25, 80%) was greater than that in the control group (6/21, 29%; χ21=12.3; P=.005). During treatment, the improvement in the Panic Disorder Severity Scale (PDSS) score in the app use group was greater than that in the control group (F1,44=7.03; P=.01). In the app use group, the total PDSS score declined by 42.5% (mean score 14.3, SD 6.5 at baseline and mean score 7.2, SD 3.6 after the intervention), whereas the PDSS score declined by 14.6% in the control group (mean score 12.4, SD 5.2 at baseline and mean score 9.8, SD 7.9 after the intervention). There were no significant differences in accumulated oxygenated hemoglobin (accHbO2) at baseline between the app use and control groups. During treatment, the reduction in accHbO2 in the right ventrolateral prefrontal cortex (VLPFC; F1,44=8.22; P=.006) and the right orbitofrontal cortex (OFC; F1,44=8.88; P=.005) was greater in the app use than the control group. CONCLUSIONS: Apps for panic disorder should effectively reduce symptoms and VLPFC and OFC brain activity in patients with panic disorder. The improvement of panic disorder symptoms was positively correlated with decreased VLPFC and OFC brain activity in the resting state. TRIAL REGISTRATION: Clinical Research Information Service KCT0007280; https://cris.nih.go.kr/cris/search/detailSearch.do?seq=21448.

Terapia Cognitivo Conductual presencial y remota para adultos con pánico en Servicios de Emergencias: tres estudios de caso / Face-to-face and remote Cognitive Behavioral Therapy for adults with panic in Emergency Services: study of three cases

Most patients with panic attacks or panic disorder who seek emergency department care go unnoticed and do not receive appropriate treatment. Although first-line psychological treatments exist for these patients, they may be insensitive and inaccessible to their characteristics. The aim of this study was to describe three different brief protocols based on Cognitive Behavioral Therapy that were adapted for face-to-face or videoconferencing application for patients with panic attacks or panic disorder seeking care in emergency department. Three cases of adult patients, two diagnosed with panic disorder and one with panic attacks, are presented to show the implementation and outcomes of the protocols on diagnostic severity, anxiety sensitivity, quality of life, health services utilization, and patient satisfaction with the protocols. As well as the use of a panic screening diagram designed for the initial evaluation of these patients. After one to seven sessions, a decrease in panic disorder severity or frequency of panic attacks, and anxiety sensitivity was observed. Quality of life improved, patients stopped using emergency department and showed satisfaction with the intervention they received. Brief interventions based on Cognitive Behavioral Therapy, both face-to-face and remote, can be implemented in emergency department to overcome some barriers to mental health access and fit the diverse care possibilities of panic patients. (AU)

Evaluation of effect of brief-intensive cognitive behavior therapy on symptoms severity in relation with catastrophic cognition in patients with panic disorder: a randomized controlled trial.

INTRODUCTION: Due to a dearth of evidence, we examined the effectiveness of brief-intensive CBT on symptom severity and catastrophic cognition in patients with panic disorder (PD). MATERIALS AND METHODS: In this randomized controlled trial, 155 patients were assigned to either the experimental group (2 successive days of brief-intensive CBT-3 h per day) or the control group (regular pharmacotherapy only). After excluding ineligible participants, 20 patients in the brief intensive CBT group and 18 patients in the control group completed the study and were included in the final analysis. The primary outcome was symptom severity, and the secondary outcome was catastrophic cognition, assessed by the Panic Disorder Severity Scale (PDSS) for symptoms severity and the Agoraphobic Cognition Scale (ACS) for cognitive assessment, respectively. RESULTS: The study showed that after one month of treatment, the PDSS (1.70 vs. 4.78; p = 0.0172) in the brief-intensive CBT group was significantly lower compared to the control group in contrast with the ACS (5.10 vs. 5.44; p = 0.8533). The mean score of PDSS and ACS significantly decreased from 21.60 to 1.7 (p < 0.0001) and from 22.55 to 5.10 (p < 0.0001) in the brief CBT group and from 19.44 to 4.78 (p < 0.0001) and 20.00 to 5.44 (p < 0.0001) in the control group, respectively. After treatment, the mean scores of PDSS and ACS significantly decreased in the brief intensive CBT and control groups. Both higher ACS and lower education levels contributed to higher PDSS in the brief intensive CBT group. However, only the PDSS correlated to the ACS in the control group. CONCLUSIONS: The study showed that brief-intensive CBT is an effective technique for reducing the severity of symptoms among PD patients. But, it was not effective to improve the cognitive level in PD patients at one month.

A causal relationship between panic disorder and risk of alzheimer disease: a two-sample mendelian randomization analysis.

BACKGROUND: Observational studies have suggested a link between panic disorder (PD) and Alzheimer disease (AD). This study aimed to identify the underlying association of PD with the risk of AD using Mendelian randomization. METHODS: Genetic instrumental variables (IVs) were retrieved in the genome-wide association study between PD and AD. Then, five different models, namely inverse variance weighting (IVW), weighted median, weighted mode, MR-Egger and MR-robust adjusted profile scores (MR-RAPS), were used for MR Analysis. Finally, the heterogeneity and pleiotropy of identified IVs were verified by multiple sensitivity tests. RESULTS: The Cochran's Q test based on MR Egger and IVW showed that no evidence of heterogeneity was found in the effects of instrumental variables, so a fixed-effect model was used. IVW analysis (OR 1.000479, 95% CI [1.000147056, 1.000811539], p = 0.005) indicated that PD was associated with an increased risk of AD, and a causal association existed between them. Meanwhile, weighted median (OR 1.000513373, 95% CI [1.000052145, 1.000974814], p = 0.029) and MR-RAPS (OR 1.000510118, 95% CI [1.000148046, 1.00087232], p = 0.006) also showed the similar findings. In addition, extensive sensitivity analyses confirmed the robustness and accuracy of these results. CONCLUSION: This investigation provides evidence of a potential causal relationship between PD and the increased risk of AD. Based on our MR results, when diagnosing and treating patients with PD, clinicians should pay more attention to their AD-related symptoms to choose therapeutic measures or minimize comorbidities. Furthermore, the development of drugs that improve both PD and AD may better treat patients with these comorbidities.

Clinical and cognitive insight in panic disorder: phenomenology and treatment effects in internet cognitive behavior therapy.

Clinical observations suggest that individuals with panic disorder (PD) vary in their beliefs about the causes of their panic attacks. Some attribute these attacks to psychological factors, while others to physiological or medical factors. These beliefs also extend to whether individuals perceive panic attacks as dangerous. In other areas of psychiatric nosology, these phenomena are commonly called clinical insight (recognition of disorder and the need for treatment) and cognitive insight (the ability to reflect on one's beliefs). Despite its importance, limited research exists on insight in PD and its relation to symptoms and treatment outcomes. This study examines clinical and cognitive insight in 83 patients with PD who received internet-based cognitive behavioral therapy, investigating their relationship with symptoms, treatment outcomes, and changes in insight. We assessed patients using interview and self-report measures of insight and symptoms. Clinical and cognitive insight were correlated and both constructs improved significantly during treatment. Good clinical insight pretreatment was positively correlated with more severe pretreatment symptoms. Pretreatment clinical and cognitive insight were not correlated with symptom change or attrition. Greater change in clinical and cognitive insight was related to greater change in symptoms. The findings highlight the significance of clinical and cognitive insight in PD, and the importance of distinguishing between them. This suggests the need to develop interventions according to patients' level of insight, particularly focusing on those lacking insight. Further research is essential to advance our understanding of the relationship between insight and the phenomenology and treatment of PD.

Brain-derived neurotrophic factor (BDNF) levels in panic disorder: A systematic review and meta-analysis.

BACKGROUND: The existing literature on the association between brain-derived neurotrophic factor (BDNF) protein levels and panic disorder presents inconsistent findings. This systematic review and meta-analysis aim to synthesize the available evidence and determine the overall effect of BDNF protein levels in individuals diagnosed with panic disorder. METHODS: A comprehensive literature search was conducted using electronic databases (PubMed, Embase, Scopus, PsycINFO, and Web of Science) from inception to April 21, 2023. The search strategy included relevant keywords and medical subject headings terms related to BDNF, panic disorder, and protein levels. A random-effects model was used for the meta-analysis, and subgroup analyses were performed to explore heterogeneity. Publication bias was assessed using funnel plots and statistical tests. RESULTS: A total of 12 studies met the inclusion criteria. The meta-analysis demonstrated a significant decrease in BDNF protein levels in individuals with panic disorder (SMD = -.53, 95% CI: -1.02 to -.04, p < .001; I2 : 92%). The results of subgroup and meta-regression analyses were not statistically significant. No significant publication bias was observed based on the results of Egger's regression test (p-value = .3550). CONCLUSION: This systematic review and meta-analysis provide evidence of lower BDNF protein levels in individuals diagnosed with panic disorder compared to healthy controls. The findings suggest a potential role for BDNF dysregulation in the pathophysiology of panic disorder. Further research is warranted to elucidate the underlying mechanisms and potential therapeutic implications.

Panicolytic-like effects of environment enrichment on male mice threatened by Bothrops jararaca lancehead pit vipers.

Environment enrichment (EE) is a well-known eustress model showing beneficial effects in different psychiatric diseases, but its positive properties in panic disorders are not yet established. The confrontation between prey and predator in complex arenas has been validated as a putative panic attack model. The principal aim of this work was to investigate the role of the EE on panic-like defensive responses elicited by mice threatened by venomous snakes. After 6 weeks of exposure either to an enriched or standard environments, 36 male mice were habituated in a complex polygonal arena for snakes containing an artificial burrow and elevated platforms for escape. The animals were confronted by Bothrops jararaca for 5 min, and the following antipredatory responses were recorded: defensive attention, stretched attend posture, flat back approach, prey versus predator interaction, oriented escape behavior, time spent in a safe place, and number of crossings. Mice threatened by snakes displayed several antipredatory reactions as compared to the exploratory behavior of those animals submitted to a nonthreatening situation (toy snake) in the same environment. Notably, EE causes anxiolytic- and panicolytic-like effects significantly decreasing the defensive attention and time spent in safe places and significantly increasing both prey versus predator interaction and exploratory behavior. In conclusion, our data demonstrate that EE can alter the processing of fear modulation regarding both anxiety- and panic-like responses in a dangerous condition, significantly modifying the decision-making defensive strategy.

Bradykinin actions in the central nervous system: historical overview and psychiatric implications.

Bradykinin (BK), a well-studied mediator of physiological and pathological processes in the peripheral system, has garnered less attention regarding its function in the central nervous system, particularly in behavioural regulation. This review delves into the historical progression of research focused on the behavioural effects of BK and other drugs that act via similar mechanisms to provide new insights into the pathophysiology and pharmacotherapy of psychiatric disorders. Evidence from experiments with animal models indicates that BK modulates defensive reactions associated with panic symptoms and the response to acute stressors. The mechanisms are not entirely understood but point to complex interactions with other neurotransmitter systems, such as opioids, and intracellular signalling cascades. By addressing the existing research gaps in this field, we present new proposals for future research endeavours to foster a new era of investigation regarding BK's role in emotional regulation. Implications for psychiatry, chiefly for panic and depressive disorders are also discussed.

Alpha1- and Beta-norepinephrinergic receptors of dorsomedial and ventromedial hypothalamic nuclei modulate panic attack-like defensive behaviour elicited by diencephalic GABAergic neurotransmission disinhibition.

Gamma-aminobutyric acid (GABA) disinhibition in medial hypothalamus (MH) nuclei of rats elicits some defensive reactions that are considered panic attack-like behaviours. Recent evidence showed that the norepinephrine-mediated system modulates fear-related defensive behaviours organised by MH neurons at least in part via noradrenergic receptors recruitment on midbrain tegmentum. However, it is unknown whether noradrenergic receptors of the MH also modulate the panic attack-like reactions. The aim of this work was to investigate the distribution of noradrenergic receptors in MH, and the effects of either α1-, α2- or ß-noradrenergic receptors blockade in the MH on defensive behaviours elaborated by hypothalamic nuclei. Defensive behaviours were evaluated after the microinjection of the selective GABAA receptor antagonist bicuculline into the MH that was preceded by microinjection of either WB4101, RX821002, propranolol (α1-, α2- and ß-noradrenergic receptor selective antagonists, respectively), or physiological saline into the MH of male Wistar rats. The α1-, α2- and ß-noradrenergic receptors were found in neuronal perikarya of all MH nuclei, and the α2-noradrenergic receptor were also found on glial cells mainly situated in the ventrolateral division of the ventromedial hypothalamic nucleus. The α1- and ß-noradrenergic receptors blockade in the MH decreased defensive attention and escape reactions elicited by the intra-MH microinjections of bicuculline. These findings suggest that, despite the profuse distributions of α1-, α2- and ß-noradrenergic receptors in the MH, both α1- and ß-noradrenergic receptor- rather than α2-noradrenergic receptor-signalling in MH are critical for the neuromodulation of panic-like behaviour.

Effects of panic-specific cognitive behavioural and psychodynamic psychotherapies on work ability in a doubly randomised clinical trial.

Objective: The effects of panic-specific psychotherapy on occupational functioning remain under-researched. This study tests whether two brief psychotherapies for Panic Disorder with or without Agoraphobia (PD/A) may generate improvement in work ability. Methods: Adults (N = 221) with a primary diagnosis of PD/A were randomised to wait-list, panic-focused psychodynamic psychotherapy (PFPP), panic control treatment (PCT), or to the choice between the two treatments. Participants completed the Work Ability Inventory (WAI) at baseline, post-treatment, and during 24-month follow-ups. Change in WAI scores were assessed using segmented multilevel linear growth models, and mediation was explored through path analysis. Results: WAI scores changed from the moderate to good range between baseline and post-treatment (SMD = 0.45; 95% CI [0.33, 0.57]) and continued to increase throughout the follow-up (SMD = 0.16; 95% CI [0.03, 0.28]) with no differences between treatments or allocation forms. In PFPP (but not in PCT) pre- to post-treatment change in WAI was mediated by reduction in panic symptoms and WAI predicted employment status and absences. Conclusions: Two brief panic specific psychotherapies, one cognitive behavioural and one psychodynamic, produced short and long-term increases in work ability.