Psychophysiological mechanisms in panic disorder: a correlative analysis of noradrenaline spillover, neuronal noradrenaline reuptake, power spectral analysis of heart rate variability, and psychological variables

A case of reinitiation of modified electroconvulsive therapy 2 weeks after modified electroconvulsive therapy-induced Takotsubo cardiomyopathy in a male patient with major depressive disorder

Background

Takotsubo cardiomyopathy (TCM) is a left ventricular dysfunction resembling acute coronary syndrome. Its prognosis is generally favorable; however, a subset of patients may present with severe complications. TCM is a rare side-effect of modified electroconvulsive therapy (ECT); it has been reported in 22 female and two male patients. Eight cases of ECT reinitiation after TCM have been reported (all females), with the shortest duration being 3 weeks.

Case Presentation

We report the case of a 61-year-old man with a history of major depressive disorder and no history of heart disease or previous ECT treatment. Antidepressants had been ineffective, and ECT was indicated. After the third ECT session, the patient complained of chest pain and shortness of breath. Electrocardiography revealed ST elevation, and catheter angiography was used to diagnose TCM. The patient had mild heart failure but remained stable. Recognizing that ECT was effective, the patient asked for it to be reinitiated. We confirmed that the cardiac function had been normalized, applied a bisoprolol fumarate patch as a preventive measure, and reinitiated ECT 14 days after the onset of TCM. ECT was performed five times, with no recurrence of TCM and a marked improvement in depression.

Conclusion

We describe a male patient with major depressive disorder who underwent reinitiation of ECT 2 weeks after ECT-induced TCM. Therefore, TCM should be recognized as a side-effect of ECT, even in men. Moreover, depending on whether the patient's condition is stable, ECT can be successfully performed in patients with TCM.

Sympathetic Pathophysiology in Hypertension Origins: The Path to Renal Denervation

The importance of the sympathetic nervous system in essential hypertension has been recognized in 2 eras. The first was in early decades of the 20th century, through to the 1960s. Here, the sympathetic nervous system was identified as a target for the treatment of hypertension, and an extensive range of antiadrenergic therapies were developed. Then, after a period of lapsed interest, in a second era from 1985 on, the development of precise measures of human sympathetic nerve firing and transmitter release allowed demonstration of the importance of neural mechanisms in the initiation and maintenance of the arterial blood pressure elevation in hypertension. This led to the development of a device treatment of hypertension, catheter-based renal denervation, which we will discuss.

Exploring the causal relationships and mediating factors between depression, anxiety, panic, and atrial fibrillation: A multivariable Mendelian randomization study

BACKGROUND

Atrial fibrillation is a significant cardiovascular disease, and the increased risk of its occurrence may be influenced by mental disorders. Currently, the causal relationship between them remains controversial. Our aim is to ascertain the relationship between atrial fibrillation and mental disorders including depression, anxiety, and panic, as well as the risk factors mediating this relationship, through the judgment of genetic susceptibility.

METHODS

We utilized the summarized statistics from nine large-scale genome-wide association studies (in European populations), including depression (PGC, N = 807,553), anxiety (FinnGen, N = 429,209), panic (PGC, N = 230,878), diabetes (UK Biobank, N = 655,666), smoking (IEU, 607,291), hypertension (UK biobank, N = 463,010), obstructive sleep apnea (IEU, N = 476,853), obesity (UK biobank, N = 463,010), and AF (IEU, N = 1,030,836). By applying bidirectional two-sample Mendelian randomization and multivariable Mendelian randomization to depression, anxiety, panic, and AF, we analyzed their causal relationships and the independent influence of specific risk factors. Furthermore, a two-step MR approach was used to assess the mediating effects of diabetes, smoking, hypertension, obstructive sleep apnea, and obesity.

RESULTS

Results from the Two-Sample Mendelian Randomization Inverse Variance Weighted Random Effects Model show: the occurrence of genetically predicted depression is related to an increased risk of atrial fibrillation (AF) (OR: 1.073; [95 % CI: 1.005-1.146] P < 0.05), and panic is more significantly associated than depression (OR: 1.017; [95 % CI: 1.008-1.027] P < 0.001), while anxiety has no causal relationship with the occurrence of AF (OR: 1.023; [95 % CI: 0.960-1.092], P > 0.05), and AF is not significantly related to the occurrence of depression, anxiety, or panic (P > 0.05). After correcting for the other two risk factors using multivariable Mendelian randomization, depression remains significantly related to the occurrence of AF (β: 0.075; 95 % CI: [0.006, 0.144], P < 0.05), while panic and anxiety are not related to the occurrence of AF. Among them, the risk factors for AF occurrence, hypertension and obesity, are mediators between depression and AF, with mediation proportions of 74.9 % and 14.3 %, respectively. The mediating effects of diabetes, smoking, and obstructive sleep apnea were found to be not statistically significant. The above results are robust after sensitivity analysis.

CONCLUSION

Our results identified that the genetic susceptibility to depression is an independent risk factor for the occurrence of AF, and that hypertension and obesity can mediate this process. Panic also poses some risk to the onset of AF. This demonstrates that controlling hypertension and obesity for emotional management is of great importance in preventing the occurrence of AF.

Impact of mental disorders on the risk of heart failure among Korean patients with diabetes: a cohort study

BACKGROUND

Few studies have assessed the correlation between coexisting mental disorders in participants with diabetes mellitus (DM) and the risk of heart failure (HF). Herein, we conducted a cohort study to determine the association between the accumulation of mental disorders in participants with DM and the risk of HF.

METHODS

The Korean National Health Insurance Service records were assessed. 2,447,386 adults with DM who underwent health screening between 2009 and 2012 were analyzed. Participants with major depressive disorder, bipolar disorder, schizophrenia, insomnia, or anxiety disorders were included. In addition, participants were categorized based on the number of coexisting mental disorders. Each participant was followed until December 2018 or until the onset of HF. Cox proportional hazard modelling with confounding factors adjustment was conducted. In addition, a competing risk analysis was conducted. Subgroup analysis assessed the impact of clinical variables on the association between the accumulation of mental disorders and the risk of HF.

RESULTS

The median follow-up duration was 7.09 years. The accumulation of mental disorders was associated with a risk of HF (zero mental disorder (0), reference; 1 mental disorder, adjusted hazard ratio (aHR): 1.222, 95% confidence intervals (CI): 1.207-1.237; 2 mental disorders, aHR: 1.426, CI: 1.403-1.448; ≥3 mental disorders, aHR: 1.667, CI: 1.632-1.70. In the subgroup analysis, the strength of association was the strongest in the younger age group (< 40 years, 1 mental disorder, aHR 1.301, CI 1.143-1.481; ≥2 mental disorders, aHR 2.683, CI 2.257-3.190; 40-64 years, 1 mental disorder, aHR 1.289, CI 1.265-1.314; ≥2 mental disorders, aHR 1.762, CI 1.724-1.801; ≥65 years, 1 mental disorder, aHR 1.164, CI 1.145-1.183; ≥2 mental disorders, aHR 1.353, CI 1.330-1.377; P_inter<0.001). In addition, income, BMI, hypertension, chronic kidney disease, history of cardiovascular disease, insulin use, and duration of DM showed significant interactions.

CONCLUSIONS

Comorbid mental disorders in participants with DM are associated with an increased risk of HF. In addition, the association was stronger in a younger age group. Participants with DM and mental disorders should be monitored with increased frequency for signs of HF; for which they have a higher risk than the general population.

Takotsubo syndrome: getting closer to its causes

Takotsubo syndrome (TTS) accounts for between 1 and 4% of cases presenting clinically as an acute coronary syndrome. It typically presents as a transient cardiac phenotype of left ventricular dysfunction with spontaneous recovery. More dramatic presentations may include cardiogenic shock or cardiac arrest. Despite progress in the understanding of the condition since its first description in 1990, considerable questions remain into understanding underlying pathomechanisms. In this review article, we describe the current published data on potential underlying mechanisms associated with the onset of TTS including sympathetic nervous system over-stimulation, structural and functional alterations in the central nervous system, catecholamine secretion, alterations in the balance and distribution of adrenergic receptors, the additive impact of hormones including oestrogen, epicardial coronary or microvascular spasm, endothelial dysfunction, and genetics as potentially contributing to the cascade of events leading to the onset. These pathomechanisms provide suggestions for novel potential therapeutic strategies in patients with TTS including the role of cognitive behavioural therapy, beta-blockers, and endothelin-A antagonists. The underlying mechanism of TTS remains elusive. In reality, physical or emotional stressors likely trigger through the amygdala and hippocampus a central neurohumoral activation with the local and systemic secretion of excess catecholamine and other neurohormones, which exert its effect on the myocardium through a metabolic switch, altered cellular signalling, and endothelial dysfunction. These complex pathways exert a regional activation in the myocardium through the altered distribution of adrenoceptors and density of autonomic innervation as a protective mechanism from myocardial apoptosis. More research is needed to understand how these different complex mechanisms interact with each other to bring on the TTS phenotype.

Effects of Genetic Mutation Sites in ADR Genes on Modern Chickens Produced and Domesticated by Artificial Selection

Associations between neurotransmitters, adrenergic receptor (ADR) mutations, and behaviors in chickens produced and domesticated by artificial selection remain unclear. This study investigates the association of neurotransmitters and ADR mutations with egg laying and cockfighting-behaviors associated with significantly different breeding backgrounds-in Shaver Brown and Shamo chickens. Accordingly, the whole sequences of nine ADR genes were determined, and nine amino acid-specific mutation sites from five genes (ADRα1A: S365G, ADRα1D: T440N, ADRα2A: D273E, ADRβ1: N443S, S445N, ADRβ3: R342C, Q404L, and P406S) were extracted. Evolutionary analysis showed that these mutations were not ancestrally derived. These results confirm that the mutations at these sites were artificially selected for domestication and are breed specific. N_ST population analysis confirmed a difference in the degree of genetic differentiation between the two populations in seven genes. The results further confirm differences in the degree of genetic differentiation between the two populations in Shaver Brown (ADRA1B and ADRA1D) and Shamo (ADRA1A and ADRA2B) chickens, indicating that the ADR gene differs between the two breeds. The effects of artificial selection, guided by the human-driven selection of desirable traits, are reflected in adrenaline gene mutations. Furthermore, certain gene mutations may affect domestication, while others may affect other traits in populations or individuals.

Melatonin as a Potential Approach to Anxiety Treatment

Anxiety disorders are the most common mental diseases. Anxiety and the associated physical symptoms may disturb social and occupational life and increase the risk of somatic diseases. The pathophysiology of anxiety development is complex and involves alterations in stress hormone production, neurosignaling pathways or free radical production. The various manifestations of anxiety, its complex pathophysiological background and the side effects of available treatments underlie the quest for constantly seeking therapies for these conditions. Melatonin, an indolamine produced in the pineal gland and released into the blood on a nightly basis, has been demonstrated to exert anxiolytic action in animal experiments and different clinical conditions. This hormone influences a number of physiological actions either via specific melatonin receptors or by receptor-independent pleiotropic effects. The underlying pathomechanism of melatonin's benefit in anxiety may reside in its sympatholytic action, interaction with the renin-angiotensin and glucocorticoid systems, modulation of interneuronal signaling and its extraordinary antioxidant and radical scavenging nature. Of importance, the concentration of this indolamine is significantly higher in cerebrospinal fluid than in the blood. Thus, ensuring sufficient melatonin production by reducing light pollution, which suppresses melatonin levels, may represent an endogenous neuroprotective and anxiolytic treatment. Since melatonin is freely available, economically undemanding and has limited side effects, it may be considered an additional or alternative treatment for various conditions associated with anxiety.

Association between Heart Rate Variability Indices and Depressed Mood in Patients with Panic Disorder

Objective

Heart rate variability (HRV) reflects the regulation of the autonomic nervous system. Panic disorder is highly associated with autonomic dysfunction, and is often accompanied by depression. The aim of this study is to determine the association between depression and HRV indices in patients with panic disorder.

Methods

A total of 110 outpatients diagnosed with panic disorder participated in this study. The medical records of patients with panic disorder who visited the outpatient clinic of Konkuk University Hospital between December 2018 and March 2020 were retrospectively reviewed. Measurements used in this study include the Panic Disorder Severity Scale-Self Report, Beck Depression Inventory (BDI-II), Insomnia Severity Index, and HRV. Patients were divided into depressive and non-depressive groups based on their BDI-II scores. The association between HRV indices and depressive symptoms was statistically analyzed.

Results

The low frequency/high frequency (LF/HF) ratio was reduced in patients with depression (mean = -0.095, p = 0.004 in the above moderate depressive group, mean = -0.120, p = 0.020 in the severe depressive group). Significant correlations were found between depressive symptoms and standard deviation of NN interval (SDNN) (ms) (-0.19, p = 0.044), very low frequency (VLF) (ms2/Hz) (-0.22, p = 0.021), LF (-0.25, p = 0.008), HF (-0.19, p = 0.043), and LF/HF (-0.25, p = 0.009). Multiple linear regression analysis showed that BDI predicted SDNN (ms), VLF (ms2/Hz), LF, HF, and LF/HF.

Conclusion

We confirmed that the LF/HF ratio decreases when depression is accompanied by panic disorder. HRV indices may be useful markers for detecting depressive symptoms in patients with panic disorder.

Effects of Xinkeshu tablets on coronary heart disease patients combined with anxiety and depression symptoms after percutaneous coronary intervention: A meta-analysis

BACKGROUND

Xinkeshu tablets (XKS), a well-known Chinese patent drug, have been administered to coronary heart disease (CHD) patients with anxiety and depression after percutaneous coronary intervention (PCI).

PURPOSE

This meta-analysis aimed to systematically evaluate the clinical effects of XKS for treating CHD patients with anxiety and depression after PCI.

METHODS

Randomized controlled trials (RCTs) about XKS alone or combined with conventional drugs for the treatment of CHD patients with anxiety and depression after PCI were retrieved from 7 databases (MEDLINE, EMBASE, the Cochrane Library, China National Knowledge Infrastructure (CNKI), Chinese Scientific Journals Database (VIP) Database, Chinese Biomedical Database (CBM) and Wanfang Database) through November 2021. First, the studies were reviewed and screened by two independent assessors according to the eligibility criteria. Second, the methodological quality of the eligible studies was evaluated based on the Cochrane Collaboration's tool for assessing the risk of bias. Subsequently, meta-analysis was performed by using RevMan 5.4 software, and publication bias was evaluated by Stata 12.0 software. Finally, the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach was applied to rate the quality of the evidence.

RESULTS

In total, 11 clinical RCTs involving 1000 patients were included in this study. This meta-analysis found that compared with conventional treatment alone, XKS combined with conventional treatment significantly improved the anxiety scale scores (SMD = -1.97, 95% CI -3.13 to -0.82; p = 0.0008; I² = 98%), the depression scores (SMD = -2.80, 95% CI -4.49 to -1.10; p = 0.001; I² = 98%), the scores on the Medical Outcomes Study 36 Item Short Form Health Survey (SF36) (MD = 11.22, 95% CI 4.19 to 18.26; p =0.002; I² = 95%) and the blood lipid levels of total cholesterol (TC) (MD = -0.38, 95% CI -0.62 to -0.13; p = 0.003; I² = 0%) and triglyceride (TG) (MD = -0.31, 95% CI -0.46 to -0.17; p < 0.0001; I² =  0%).

CONCLUSION

The current evidence suggests that XKS might benefit CHD patients experiencing anxiety and depression after PCI by helping to improve their depression symptoms, TC and TG blood lipid levels. However, due to insufficient methodological quality of the studies, several risks of bias and inadequate reporting of the clinical data, more rigorous, multicenter, sufficient-sample and double-blind randomized clinical trials are warranted.

The Octopus Trap of Takotsubo and Stroke: Genetics, Biomarkers and Clinical Management

Takotsubo cardiomyopathy (TC) is a reversible cardiomyopathy mimicking an acute coronary syndrome, usually observed in response to acute stress situations. The association between acute ischemic stroke and TC is already known, since it has been previously reported that ischemic stroke can be both a consequence and a potential cause of TC. However, the precise pathophysiological mechanism linking the two conditions is still poorly understood. The aim of our review is to expand insights regarding the genetic susceptibility and available specific biomarkers of TC and to investigate the clinical profile and outcomes of patients with TC and stroke. Since evidence and trials on TC and stroke are currently lacking, this paper aims to fill a substantial gap in the literature about the relationship between these pathologies.

Measurement of Noradrenaline and Serotonin Metabolites With Internal Jugular Vein Sampling: An Indicator of Brain Monoamine Turnover in Depressive Illness and Panic Disorder

In research spanning three decades we have estimated brain monoamine turnover (approximately equating with synthesis rate) with sampling from the internal jugular veins and measurement of trans-cerebral plasma monoamine metabolite concentration gradients. Here we report indices of brain noradrenaline and serotonin turnover in patients with major depressive illness (MDD) and panic disorder (PD). Brain noradrenaline turnover was assessed from the combined flux into the internal jugular veins of the metabolites dihydroxyphenylglycol (DHPG) and 3-hydroxy-4-methoxyphenylglycol (MHPG), and brain serotonin turnover from the overflow of the primary metabolite, 5-hydroxyindole acetic acid (5HIAA). Comparison was made with matched healthy research participants. In both MD and PD the estimate of brain noradrenaline turnover provided by metabolite overflow was unremarkable. In contrast, in both patient groups the estimate of brain serotonin turnover provided by 5HIAA overflow was increased 3-4-fold (P < 0.01). This neurotransmitter abnormality was normalized in MDD and PD in clinical remission, during selective serotonin reuptake blocker (SSRI) dosing. We cannot be sure if the brain serotonergic abnormality we find in MDD and PD is causal or a correlate. Measurements in PD were not made during a panic attack. The increased estimated serotonin turnover here may possibly be a substrate for panic attacks; serotonergic raphe nuclei participate in anxiety responses in experimental animals. It is puzzling that the findings were identical in MDD and PD, although it may be pertinent that these psychiatric diagnoses are commonly comorbid. It is unlikely that activation of brain serotonergic neurons is driving the sympathetic nervous activation present, which contributes to cardiovascular risk, persistent sympathetic activation in MDD and episodic activation in PD during panic attacks. We have previously demonstrated that the mechanism of activation of human central sympathetic outflow in other contexts (hypertension, heart failure) is activation of noradrenergic brainstem neurons projecting to the hypothalamus and amygdala.

Sympathetic Neural Control in Humans with Anxiety-Related Disorders

Numerous conceptual models are used to describe the dynamic responsiveness of physiological systems to environmental pressures, originating with Claude Bernard's milieu intérieur and extending to more recent models such as allostasis. The impact of stress and anxiety upon these regulatory processes has both basic science and clinical relevance, extending from the pioneering work of Hans Selye who advanced the concept that stress can significantly impact physiological health and function. Of particular interest within the current article, anxiety is independently associated with cardiovascular risk, yet mechanisms underlying these associations remain equivocal. This link between anxiety and cardiovascular risk is relevant given the high prevalence of anxiety in the general population, as well as its early age of onset. Chronically anxious populations, such as those with anxiety disorders (i.e., generalized anxiety disorder, panic disorder, specific phobias, etc.) offer a human model that interrogates the deleterious effects that chronic stress and allostatic load can have on the nervous system and cardiovascular function. Further, while many of these disorders do not appear to exhibit baseline alterations in sympathetic neural activity, reactivity to mental stress offers insights into applicable, real-world scenarios in which heightened sympathetic reactivity may predispose those individuals to elevated cardiovascular risk. This article also assesses behavioral and lifestyle modifications that have been shown to concurrently improve anxiety symptoms, as well as sympathetic control. Lastly, future directions of research will be discussed, with a focus on better integration of psychological factors within physiological studies examining anxiety and neural cardiovascular health. © 2022 American Physiological Society. Compr Physiol 12:1-33, 2022.

Pivotal role of the sympathetic nerves of the human heart in mental stress responses and triggered cardiovascular catastrophes

Mental stress can trigger cardiac catastrophes, explicitly evident during national disasters such as earthquakes. Activation of the cardiac sympathetic outflow and inhibition of the cardiac vagus are important mediating mechanisms. This manuscript describes efforts by the Human Neurotransmitters Research Laboratory of the Baker Institute in Melbourne to develop investigative methods to study the sympathetic nerves of the human heart, and to apply these in mental stress research. With laboratory mental stress, activation of the adrenal medulla was found to occur, accompanied by a regionalized sympathetic nervous response directed to the heart, but sparing the sympathetic outflow to the skeletal muscle vasculature. Patients with panic disorder are at increased cardiovascular risk. They exhibit high-level sympathetic activation during a panic attack, sometimes accompanied by coronary artery spasm. Patients with sudden ventricular arrhythmias causing collapse in the community were found to have as the predisposing substrate high baseline cardiac sympathetic activity, from previously unrecognized mild heart failure; it was surprising at the time that we did not find critical coronary artery stenosis as the substrate. In some the arrhythmia event had a behavioural trigger. In Takotsubo cardiomyopathy ("Broken Heart Syndrome") the myocardial stunning appears to represent a catecholamine cardiomyopathy, from astronomically high plasma adrenaline concentrations, rather than be caused by activation of the cardiac sympathetic nerves. Some diseases (essential hypertension, heart failure, panic disorder) have forms of sympathetic neural enhancement which contribute to cardiovascular risk: reuptake of noradrenaline by sympathetic nerves after release is faulty and single sympathetic fibres fire in multiple salvos within a single cardiac cycle. Paradoxically, obesity-hypertension does not share in this sympathetic neural augmentation, which is present only in normal-weight hypertensive patients, providing the possible basis for an observed "Obesity Paradox" (longer survival in obesity-hypertension than in normal weight hypertension). Community-wide specific prevention of cardiovascular triggering is not currently possible, due to there being no available simple screening tests which could be applied to the community at-large for the commonest substrates, silent coronary artery disease and mild heart failure. Standard medical preventive measures for coronary atherosclerosis will of course be helpful. Targeted prevention of triggering can be done in those with a detected predisposing substrate, such as genetic Long QT Syndrome, and in survivors of a serious triggered event, who need detailed, appropriate testing.

Heart Rate Variability is an Independent Predictor of Lymph Node Metastasis in Patients with Cervical Cancer

Purpose

Heart rate variability (HRV) has been reported as a useful biomarker for prognostic factors in a variety of cancers. The purpose of this study was to explore the predictive value of preoperative HRV for lymph node metastasis (LNM) in patients with cervical cancer (CC).

Patients and Methods

A total of 77 patients with CC were included, including 18 LNM and 59 non-LNM patients. A five-minute resting electrocardiogram (ECG) was collected before surgery for the analysis of HRV time domain, frequency domain and Poincaré plot parameters (ie, SDNN, RMSSD, LF, HF, LF/HF, SD1, SD2 and SD2/SD1). Student’s t-tests and logistic regression were performed to determine the relationship between HRV and LNM.

Results

The LNM group had significantly lower SDNN, LF, and SD2 than the non-LNM group (all p < 0.05; all Cohen’s d > 0.5). Binary logistic regression analysis indicated that SDNN, LF and SD2 were still significantly associated with LNM. Specifically, for each 1 ms decrease in SDNN and SD2 and each 1 logarithmic unit decrease in ln (LF), the odds of LNM increased by 12%, 9%, and 86%, respectively (all p < 0.05).

Conclusion

These findings suggest an association between HRV and CC LNM, and HRV could be a potential noninvasive biomarker for the prediction of LNM in CC patients.

Takotsubo syndrome: the broken-heart syndrome

Takotsubo syndrome - also known as broken-heart syndrome, Takotsubo cardiomyopathy, and stress-induced cardiomyopathy - is a recently discovered acute cardiac disease first described in Japan in 1991. This review aims to update understanding on the epidemiology, pathophysiology, clinical presentation, diagnosis, and treatment of Takotsubo syndrome, highlighting aspects of interest to cardiologists and general practitioners.

Takotsubo syndrome and rheumatic diseases-a critical systematic review

Since its description in 1990, Takotsubo syndrome (TTS), an acute cardiac condition triggered by physical or emotional stress, has been believed to be related to catecholamine surge from overwhelming sympathetic activity. While symptomatology, biochemical features, ECG and echocardiogram alterations are largely indistinguishable from acute coronary syndrome, the absence of culprit coronary lesions often necessitates further investigations, uncovering underlying inflammatory processes. Mechanistically, animal models of TTS reveal early neutrophil infiltration followed by staged ingression of two subtypes of macrophages (M1, M2) mediating initial acute inflammatory changes (M1), followed by switching to anti-inflammatory signals (M2) that enhance myocardial tissue recovery. Here, we begin with a description of two TTS patients with primary Sjögren's syndrome and Takayasu's arteritis, followed by a systematic literature review that summarizes the demographic and clinical features of TTS patients with rheumatological conditions. Potential impact of disease manifestations and treatment of rheumatological conditions on TTS are critically discussed.

Heart rate variability as a biobehavioral marker of diverse psychopathologies: A review and argument for an "ideal range"

Heart rate variability (HRV), a measure of the variability in intervals between subsequent heart beats, is now widely considered an index of emotion regulatory capacity and the ability to adapt flexibly to changing environmental demands. Abnormalities in HRV are implicated in a host of psychopathologies, making it a potentially powerful transdiagnostic biobehavioral change mechanism in treatment interventions. While most mental illnesses are associated with low HRV, eating disorders have been linked to elevated HRV. We examined 62 research articles on HRV in psychopathology to test the hypothesis that there is an "ideal range" of HRV that predicts optimal functioning. Relationships between symptom severity and parameters that quantify HRV were examined graphically. More extreme time-domain HRV measures, both high and low, were associated with psychopathology, whereas healthy controls displayed mid-range values. Findings preliminarily support the hypothesis that there is an "ideal range" of HRV that could be targeted in biofeedback interventions.

Takotsubo cardiomyopathy in children

OBJECTIVE

To explore the epidemiology and outcomes of takotsubo cardiomyopathy in children.

METHODS

A retrospective analysis of the Healthcare Cost and Utilization 2012 and 2016 Kids' Inpatient Database was performed. Patients admitted with the diagnosis of takotsubo cardiomyopathy in the age group of 1 month-20 years were identified using International Classification of Diseases (ICD)-9 code 429.83 and ICD-10 code I51.81.

RESULTS

Among a total of 4,860,859 discharges, there were 153 with the diagnosis of takotsubo cardiomyopathy (3.1 per 100,000 discharges). Among patients with takotsubo cardiomyopathy, 55.0% were male, 62.4% were white, and 16.7% were black. Eighty-nine percent of patients were between 12 and 20 years. Psychiatric diagnosis was documented in 46% and substance use disorder in 36.2%. Sepsis was documented in 22.8% of patients. The median length of stay was 5 days (interquartile range: 2.7-15), and median total charges were $75,080 (interquartile range: 32,176-198,336). The overall mortality for takotsubo cardiomyopathy was 7%. On multivariable regression analysis, mortality was higher in the presence of anoxic injury (odds ratio = 34.42, 95% confidence interval: 4.85-320.11, p = 0.00).

CONCLUSIONS

Takotsubo cardiomyopathy is uncommon in children and carries a mortality rate of 7%. Most children with takotsubo cardiomyopathy are adolescent males, many of whom have psychiatric disorder or substance use disorder or both. Takotsubo cardiomyopathy should be considered in the differential diagnosis for patients who present with cardiac dysfunction and have underlying psychiatric disorders or drug abuse.

A pilot study augmenting cognitive behavioral therapy for panic disorder with attention bias modification: Clinical and psychophysiological outcomes

BACKGROUND AND OBJECTIVES

Studies show that attentional bias towards threat is a key maintenance factor for panic disorder (PD). Attentional bias may be an important mechanism of symptom reduction, and thus, a useful target for optimizing outcomes. The current study examined whether an attention bias modification (ABM) task enhanced CBT outcomes. Multiple methods for assessing PD were used, including physiological measurement and clinician-rated assessment.

METHODS

Adults with panic disorder (N = 24) received seven sessions of CBT with either ABM or sham attention tasks. Psychophysiological reaction to a loud tones startle paradigm was assessed before and after treatment.

RESULTS

Across both groups, panic symptom severity decreased with CBT. The ABM group showed greater reductions in PD symptoms compared to the placebo group. Notably, however, changes in attentional bias were not associated with symptom reductions across groups. No significant group differences on psychophysiological assessment were observed.

LIMITATIONS

This study is limited by the small sample size, which rendered our power to investigate mediators and moderators insufficient. More research is needed to validate the effect of attention bias modification on attentional bias to threat.

CONCLUSIONS

This pilot study suggests that future research should investigate attentional bias in conjunction with CBT. A larger sample would provide opportunity to further investigate the mechanisms through which ABM works, along with potential moderating factors and the use of psychophysiological measurements in panic disorder.

Impact of sex and age on metabolism, sympathetic activity, and hypertension

In this brief review, we summarize the current knowledge on the complex interplay between metabolism, sympathetic activity and hypertension with a focus on sex differences and changes with age in humans. Evidence suggests that in premenopausal women, sex hormones, particularly estrogen exerts a profound cardioprotective effect which may be associated with favorable metabolic profiles, as well as lower sympathetic activity and blood pressure at rest and any given physiological and environmental stimuli compared with men of a similar age. Along this line, premenopausal women seem to be generally protected from obesity-induced metabolic and cardiovascular complications. However, postmenopausal estrogen deprivation during midlife and older age has a detrimental impact on metabolism, may lead to adipose tissue redistribution from the subcutaneous to abdominal area, and augments sympathetic activity. All these changes could contribute significantly to the higher prevalence of hypertension and greater cardiometabolic risk in older women than older men. It is proposed that obesity-related hypertension has a neurogenic component which is characterized by sympathetic overactivity, but the impact of sex and age remains largely unknown. Understanding sex and age-specific differences in obesity and sympathetic neural control of blood pressure is important in the prevention and/or risk reduction of cardiometabolic disorders for both men and women.

Analysis of the source of aggressiveness in gamecocks

Although the fighting behaviour in gamecocks has evolved because of artificial selection, it is unknown whether the selection for aggressiveness affects neurotransmitter levels in the avian central nervous system. We sought to identify the source and origin of this trait. We collected the brain samples from 6 female Shamo gamecocks and 5 Shaver Brown chickens (control; bred for egg production). The midbrain levels of norepinephrine (NE) were significantly higher in Shamo gamecocks (P = 0.0087) than in the controls. Moreover, alleles encoding adrenergic receptors differed between the breeds in terms of response to NE. Gene mutations specific to Shamo and potentially associated with fighting behaviour were in sites T440N of ADRα1D; V296I of ADRα2A; and T44I, Q232R, and T277M of ADRβ2. The evolutionary analysis indicated that the ADRβ2 (T44I and Q232R) mutations were heritable in all Galliformes, whereas the T440N mutation of ADRα1D and V296I mutations of ADRα2A were unique to Shamo and originated by artificial selection. A high NE level may confer a selective advantage by enabling gamecocks to be aggressive and pain tolerant. Therefore, the strong fighting behaviour of Shamo has resulted from a combination of naturally inherited and mutant genes derived by artificial selection.

Take my breath away: Neural activation at breath-hold differentiates individuals with panic disorder from healthy controls

There is neuroanatomical evidence of an "extended fear network" of brain structures involved in the etiology of panic disorder (PD). Although ventilatory distrubance is a primary symptom of PD these sensations may also trigger onset of a panic attack (PA). Here, a voluntary breath-holding paradigm was used to mimic the hypercapnia state in order to compare blood oxygen level-dependent (BOLD) response, at the peak of a series of 18 s breath-holds, of 21 individuals with PD to 21 low anxiety matched controls. Compared to the rest condition, BOLD activity at the peak (12 - 18 s) of the breath-hold was greater for PD versus controls within a number of structures implicated in the extended fear network, including hippocampus, thalamus, and brainstem. Activation was also observed in cortical structures that are shown to be involved in interoceptive and self-referential processing, such as right insula, middle frontal gyrus, and precuneus/posterior cingulate. In lieu of amygdala activation, our findings show elevated activity throughout an extended network of cortical and subcortical structures involved in contextual, interoceptive and self-referential processing when individuals with PD engage in voluntary breath-holding.

Anxiety and Depression After a Cardiac Event: Prevalence and Predictors

Introduction

Patients who are anxious or depressed after an acute cardiac event are at increased risk of a subsequent event and premature death. It is therefore important to identify these patients early in order to initiate supportive or even preventive measures. In the present study, we report on the prevalence of anxiety and depression during the first 12 months after an acute cardiac event, and the patient characteristics predictive of increased anxiety and depression risk in early and late convalescence.

Methods

We recruited a sample of 911 patients with acute myocardial infarction (AMI), acute coronary syndrome (ACS), and/or unstable angina (UA), and/or undergoing coronary artery bypass graft surgery (CABGS). Patients completed the Hospital Anxiety and Depression Scale (HADS) close to the time of their event, and again during early (2–4 months post-event) and late (6–12 months post-event) convalescence. Using HADS-A and HADS-D cut-offs of 8+, prevalence rates for anxiety, depression, and comorbid anxiety and depression were determined for each timepoint. Chi-square tests and odds ratios were used to identify baseline patient characteristics associated with increased anxiety and depression risk over 12 months.

Results

Anxiety rates were 43, 28, and 27% at the time of the event, early, and late convalescence. Depression rates were 22, 17, and 15%, respectively. Factors consistently associated with increased anxiety and depression risk were history of depression, financial strain, poor self-rated health, low socioeconomic status, younger age (<55 years), and smoking. Obesity, diabetes, and social isolation (living alone or being unpartnered) were identified as important albeit less significant risk factors. Neither sex nor event type were predictive of anxiety or depression.

Conclusion

This large patient sample provided the opportunity to identify rates of anxiety and depression during the 12 months after a cardiac event and key patient characteristics for increased risk. These risk factors are easily identifiable at the time of the event, and could be used to guide the targeting of support programs for patients at risk.

International Expert Consensus Document on Takotsubo Syndrome (Part I): Clinical Characteristics, Diagnostic Criteria, and Pathophysiology

Takotsubo syndrome (TTS) is a poorly recognized heart disease that was initially regarded as a benign condition. Recently, it has been shown that TTS may be associated with severe clinical complications including death and that its prevalence is probably underestimated. Since current guidelines on TTS are lacking, it appears timely and important to provide an expert consensus statement on TTS. The clinical expert consensus document part I summarizes the current state of knowledge on clinical presentation and characteristics of TTS and agrees on controversies surrounding TTS such as nomenclature, different TTS types, role of coronary artery disease, and etiology. This consensus also proposes new diagnostic criteria based on current knowledge to improve diagnostic accuracy.

A functional genetic variation of SLC6A2 repressor hsa-miR-579-3p upregulates sympathetic noradrenergic processes of fear and anxiety

Increased sympathetic noradrenergic signaling is crucially involved in fear and anxiety as defensive states. MicroRNAs regulate dynamic gene expression during synaptic plasticity and genetic variation of microRNAs modulating noradrenaline transporter gene (SLC6A2) expression may thus lead to altered central and peripheral processing of fear and anxiety. In silico prediction of microRNA regulation of SLC6A2 was confirmed by luciferase reporter assays and identified hsa-miR-579-3p as a regulating microRNA. The minor (T)-allele of rs2910931 (MAF_cases = 0.431, MAF_controls = 0.368) upstream of MIR579 was associated with panic disorder in patients (p_allelic = 0.004, n_cases = 506, n_controls = 506) and with higher trait anxiety in healthy individuals (p_ASI = 0.029, p_ACQ = 0.047, n = 3112). Compared to the major (A)-allele, increased promoter activity was observed in luciferase reporter assays in vitro suggesting more effective MIR579 expression and SLC6A2 repression in vivo (p = 0.041). Healthy individuals carrying at least one (T)-allele showed a brain activation pattern suggesting increased defensive responding and sympathetic noradrenergic activation in midbrain and limbic areas during the extinction of conditioned fear. Panic disorder patients carrying two (T)-alleles showed elevated heart rates in an anxiety-provoking behavioral avoidance test (F(2, 270) = 5.47, p = 0.005). Fine-tuning of noradrenaline homeostasis by a MIR579 genetic variation modulated central and peripheral sympathetic noradrenergic activation during fear processing and anxiety. This study opens new perspectives on the role of microRNAs in the etiopathogenesis of anxiety disorders, particularly their cardiovascular symptoms and comorbidities.

International Expert Consensus Document on Takotsubo Syndrome (Part I): Clinical Characteristics, Diagnostic Criteria, and Pathophysiology

Takotsubo syndrome (TTS) is a poorly recognized heart disease that was initially regarded as a benign condition. Recently, it has been shown that TTS may be associated with severe clinical complications including death and that its prevalence is probably underestimated. Since current guidelines on TTS are lacking, it appears timely and important to provide an expert consensus statement on TTS. The clinical expert consensus document part I summarizes the current state of knowledge on clinical presentation and characteristics of TTS and agrees on controversies surrounding TTS such as nomenclature, different TTS types, role of coronary artery disease, and etiology. This consensus also proposes new diagnostic criteria based on current knowledge to improve diagnostic accuracy.

Neurotransmitter Switching Coupled to β-Adrenergic Signaling in Sympathetic Neurons in Prehypertensive States

Single or combinatorial administration of β-blockers is a mainstay treatment strategy for conditions caused by sympathetic overactivity. Conventional wisdom suggests that the main beneficial effect of β-blockers includes resensitization and restoration of β1-adrenergic signaling pathways in the myocardium, improvements in cardiomyocyte contractility, and reversal of ventricular sensitization. However, emerging evidence indicates that another beneficial effect of β-blockers in disease may reside in sympathetic neurons. We investigated whether β-adrenoceptors are present on postganglionic sympathetic neurons and facilitate neurotransmission in a feed-forward manner. Using a combination of immunocytochemistry, RNA sequencing, Förster resonance energy transfer, and intracellular Ca2+ imaging, we demonstrate the presence of β-adrenoceptors on presynaptic sympathetic neurons in both human and rat stellate ganglia. In diseased neurons from the prehypertensive rat, there was enhanced β-adrenoceptor-mediated signaling predominantly via β2-adrenoceptor activation. Moreover, in human and rat neurons, we identified the presence of the epinephrine-synthesizing enzyme PNMT (phenylethanolamine-N-methyltransferase). Using high-pressure liquid chromatography with electrochemical detection, we measured greater epinephrine content and evoked release from the prehypertensive rat cardiac-stellate ganglia. We conclude that neurotransmitter switching resulting in enhanced epinephrine release, may provide presynaptic positive feedback on β-adrenoceptors to promote further release, that leads to greater postsynaptic excitability in disease, before increases in arterial blood pressure. Targeting neuronal β-adrenoceptor downstream signaling could provide therapeutic opportunity to minimize end-organ damage caused by sympathetic overactivity.

The Sympathetic Nervous System in the Pathogenesis of Takotsubo Syndrome

Takotsubo syndrome is a unique clinical condition of acute heart failure and reversible left ventricular dysfunction frequently precipitated by sudden emotional or physical stress. There is growing evidence that exaggerated sympathetic stimulation is central to the pathogenesis of this syndrome. Precisely how catecholamines mediate myocardial stunning in takotsubo syndrome remains incompletely understood; but possible mechanisms include epicardial spasm, microvascular dysfunction, direct adrenergic-receptor-mediated myocyte injury, and systemic vascular effects that alter ventricular-arterial coupling. Risk factors that increase sympathetic tone and/or catecholamine sensitivity may render individuals particularly susceptible to takotsubo syndrome during episodes of acute stress.

A polymorphism in the norepinephrine transporter gene is associated with affective and cardiovascular disease through a microRNA mechanism

Norepinephrine released from sympathetic nerves is removed from the neuroeffector junction via the action of the norepinephrine transporter (NET). NET impairment is evident in several clinically important conditions including major depressive disorder (MDD), panic disorder (PD), essential hypertension and the postural orthostatic tachycardia syndrome (POTS). We aimed to determine whether a single nucleotide polymorphism (SNP) in the 3' untranslated region (UTR) of the NET gene is associated with NET impairment and to elucidate the mechanisms involved. The analyses were carried out in two cohorts of European ancestry, which included healthy controls and MDD, PD, hypertensive and POTS patients. Compared with controls, cases had significantly higher prevalence of the T allele of rs7194256 (C/T), arterial norepinephrine, depression and anxiety scores, larger left ventricular mass index, higher systolic and diastolic blood pressures, and heart rate. Bioinformatic analysis identified that the microRNA miR-19a-3p could bind preferentially to the sequence created by the presence of the T allele. This was supported by results of luciferase assays. Compared with controls, cases had significantly lower circulating miR-19a-3p, which was associated with pathways related to blood pressure and regulation of neurotransmission. In vitro norepinephrine downregulated miR-19a-3p. In conclusion, the T allele of the rs7194256 SNP in the 3'UTR of the NET gene is more prevalent in diseases where NET impairment is evident. This might be explained by the creation of a binding site for the microRNA miR-19a-3p. A defect in NET function may potentiate the sympathetic neurochemical signal, predisposing individuals with affective diseases to increased risk of cardiovascular disease development.

Mental stress and human cardiovascular disease

The London physician and neuroanatomist Thomas Willis in the 17th century correctly attributed the source of emotions to the brain, not the heart as believed in antiquity. Contemporary research documents the phenomenon of "triggered" heart disease, when the autonomic nervous system control of the heart by the brain goes awry, producing heart disease of sudden onset, precipitated by acute emotional upheaval. This can take the form of, variously, cardiac arrhythmias, myocardial infarction, Takotsubo cardiomyopathy and sudden death. Chronic psychological distress also can have adverse cardiovascular consequences, in the causal linkage of depressive illness to heart disease, and in the probable causation of atherosclerosis and hypertension by chronic mental stress. In patients with essential hypertension, stress biomarkers are present. The sympathetic nervous system is the usual mediator between these acute and chronic psychological substrates and cardiovascular disease.

Psychiatric history, post-discharge distress, and personality characteristics among incident female cases of takotsubo cardiomyopathy: A case-control study

BACKGROUND

The role of psychological factors in the onset of takotsubo cardiomyopathy (TC) is still controversial. Associations with previous psychiatric conditions are registry-based; associations with personality characteristics and psychological sequelae of TC have been largely unexplored. This case-control study sought to study pre-admission psychiatric morbidity, personality traits, and post-discharge distress in incident cases of TC.

METHODS

TC cases (Mayo clinic criteria) and acute myocardial infarction (MI) controls were recruited among women admitted to two Emergency Departments in New England. Healthy controls (HC) were recruited from a volunteers' registry. Preadmission psychiatric history (DSM-IV-TR) was abstracted from the medical record. PTSD symptoms (Impact of Events Scale); distress (Hospital Anxiety and Depression Scale); perceived stress (PS scale) and personality traits (optimism; hostility, type D personality) were collected via phone interview one month after discharge.

RESULTS

From March 2013 through October 2015, 107 participants (45 TC, 32 MI and 30 HC) were enrolled. The prevalence of preadmission anxiety disorders was 24.4% in TC, 9.4% in MI, and 0 in HC (p = 0.007) while that of mood disorders was similar across groups. TC had higher psychological distress, perceived stress, and PTSD symptoms post-discharge vs. MI and HC. In adjusted models, PTSD symptoms remained higher in TC vs. MI (b = 0.55, p < 0.05) and vs. HC (b = 0.92, p < 0.01). Optimism and hostility scores were similar across groups, while type D (social inhibition) scores were higher in TC and MI vs. HC.

CONCLUSIONS

Preadmission anxiety, but not depression, was associated with the occurrence of TC. High distress and PTSD symptoms post-discharge indicate that TC women may be at risk for poor psychological adjustment.

Increased prevalence of anxiety and depression symptoms in patients with coronary artery disease before and after percutaneous coronary intervention treatment

BACKGROUND

Evidence suggests that coronary heart disease (CHD) is associated with increased anxiety and a high incidence of comorbid anxiety and depression. However, the association between percutaneous coronary intervention (PCI) and comorbid anxiety and depression has not been previously investigated. This study aims to determine the relationship between PCI and anxiety and depression symptoms in CHD patients in terms of the occurrence, prone factors, and long-term outcomes of CHD.

METHODS

One hundred seventy CHD patients who underwent PCI treatment between September 2013 and February 2014 at the Second Hospital of Hebei Medical University were randomly selected. All patients independently completed the Hospital Anxiety and Depression Scale (HADS) and a preoperative questionnaire; they also provided details regarding their PCI-related concerns one day before PCI, as well as one day and one, three, six, and 12 months after PCI.

RESULTS

PCI treatment was significantly associated with the symptoms of anxiety, depression, affective disorders, and comorbid anxiety and depression (χ(2) = 90.18, 54.45, 101.59, 64.83; p < 0.01) at each follow-up time point. Moreover, PCI treatment was linearly correlated with each of these psychological issues (p < 0.01).

CONCLUSION

The prevalence of anxiety, depression, and comorbid anxiety and depression symptoms significantly increases one day before and after PCI treatment; however, the incidence of these psychological issues significantly decreases with time following PCI. A low level of education, apprehension with regard to nursing quality, potential cardiac dysfunction, surgery sequelae, and surgery failure are also associated with a high prevalence of anxiety and depression symptoms.

Is there cardiac risk in panic disorder? An updated systematic review

BACKGROUND

The recognized relationship between panic disorder (PD) and cardiac disorders (CDs) is not unequivocal. We reviewed the association between PD and coronary artery disease (CAD), arrhythmias, cardiomyopathies, and sudden cardiac death.

METHODS

We undertook an updated systematic review, according to PRISMA guidelines. Relevant studies dating from January 1, 2000, to December 31, 2014, were identified using the PubMed database and a review of bibliographies. The psychiatric and cardiac diagnostic methodology used in each study was then to very selective inclusion criteria.

RESULTS

Of 3044 studies, 14 on CAD, 2 on cardiomyopathies, and 1 on arrhythmias were included. Overall, the studies supported a panic-CAD association. Furthermore, in some of the studies finding no association between current full-blown PD and CAD, a broader susceptibility to panic, manifesting as past PD, current agoraphobia, or subthreshold panic symptoms, appeared to be relevant to the development of CAD. Preliminary data indicated associations between panic, arrhythmias, and cardiomyopathies.

LIMITATIONS

The studies were largely cross-sectional and conducted in cardiological settings. Only a few included blind settings. The clinical conditions of patients with CDs and the qualifications of raters of psychiatric diagnoses were highly heterogeneous. CDs other than CAD had been insufficiently investigated.

CONCLUSIONS

Our review supported a relationship between PD and CDs. Given the available findings and the involvement of the cardiorespiratory system in the pathophysiology of PD, an in-depth investigation into the panic-CDs association is highly recommended. This should contribute to improved treatment and prevention of cardiac events and/or mortality, linked to PD.

Autonomic nervous system dysfunction in psychiatric disorders and the impact of psychotropic medications: a systematic review and meta-analysis

BACKGROUND

Autonomic nervous system (ANS) dysfunction is a putative underlying mechanism for increased cardiovascular disease risk in individuals with psychiatric disorders. Previous studies suggest that this risk may be related to psychotropic medication use. In the present study we systematically reviewed and analyzed published studies of heart rate variability (HRV), measuring ANS output, to determine the effect of psychiatric illness and medication use.

METHODS

We searched for studies comparing HRV in physically healthy adults with a diagnosed psychiatric disorder to controls and comparing HRV pre- and post-treatment with a psychotropic medication.

RESULTS

In total, 140 case-control (mood, anxiety, psychosis, dependent disorders, k = 151) and 30 treatment (antidepressants, antipsychotics; k = 43) studies were included. We found that HRV was reduced in all patient groups compared to controls (Hedges g = -0.583) with a large effect for psychotic disorders (Hedges g = -0.948). Effect sizes remained highly significant for medication-free patients compared to controls across all disorders. Smaller and significant reductions in HRV were observed for specific antidepressants and antipsychotics.

LIMITATIONS

Study quality significantly moderated effect sizes in case-control analyses, underscoring the importance of assessing methodological quality when interpreting HRV findings.

CONCLUSION

Combined findings confirm substantial reductions in HRV across psychiatric disorders, and these effects remained significant even in medication-free individuals. Reductions in HRV may therefore represent a significant mechanism contributing to elevated cardiovascular risk in individuals with psychiatric disorders. The negative impact of specific medications on HRV suggest increased risk for cardiovascular disease in these groups, highlighting a need for treatment providers to consider modifiable cardiovascular risk factors to attenuate this risk.

Salivary alpha-amylase response following repeated psychosocial stress in patients with panic disorder

BACKGROUND

This study examined autonomic responses (salivary alpha-amylase, sAA; heart rate, HR) to repeated psychosocial stress as a candidate mechanism linking autonomic hyper-arousal and sensitization to the occurrence of panic disorder (PD).

METHODS

Thirty-three patients with PD and 34 healthy controls were exposed to the Trier Social Stress Test (TSST) twice on consecutive days.

RESULTS

sAA changes were comparable between PD and controls on both testing days with overall decreasing sAA responses (delta) on day two. In contrast, HR delta increased on day two in both groups. This sensitization was driven by female controls while male PD showed most pronounced HR changes to the first TSST.

CONCLUSIONS

Overall, a general autonomic hyper-arousal in PD could not be confirmed. In contrast, sAA responses slightly habituated to repeated stress. Whether sAA findings mirror assumed habituation effects of repeated stress exposure on normalizing autonomic reactivity remains to be investigated in longitudinal studies.

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

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

Association of depressive and anxiety symptoms with 24-hour urinary catecholamines in individuals with untreated high blood pressure

OBJECTIVE

Depression and anxiety are considered risk factors for cardiovascular disease (CVD). The explanatory mechanisms, however, are still to be characterized. One proposed pathophysiological pathway is dysregulation of the autonomic nervous system, including heightened sympathetic nervous system activity. This study examined the relationship between symptoms of depression, anxiety, and sympathetic nervous system activity in individuals with untreated high blood pressure.

METHODS

A total of 140 participants with untreated high blood pressure (55% white, 38.5% female, mean [standard deviation] age = 45.5 [8.55] years) collected urine over a 24-hour period on 3 separate occasions. Urine samples were assayed for mean 24-hour epinephrine (EPI24) and norepinephrine excretion. Depressive symptoms were assessed using the Beck Depression Inventory, with anxiety symptoms assessed using the Spielberger State-Trait Anxiety Inventory.

RESULTS

Depression and anxiety scores were intercorrelated (r = 0.76, p < .001). EPI24 was positively correlated with anxiety (r = 0.20, p = .02) but not depression (r = 0.02, p = .77), whereas 24-hour urinary norepinephrine excretion was not correlated with anxiety (r = 0.10, p = .21) or with depression (r = 0.07, p = .39). Regression models, accounting for sex, age, body mass index, race, mean systolic ambulatory blood pressure, tobacco use, alcohol use, physical activity, and sleep efficiency confirmed that anxiety was associated with EPI24 excretion (p = .023) and that depressive symptoms were not (p = .54).

CONCLUSIONS

Anxiety was associated with heightened sympathoadrenal activity, suggesting a biological pathway through which anxiety could increase CVD risk. Anxiety and depression may confer increased CVD risk via different mechanisms.

Recurrent Tako-Tsubo cardiomyopathy (TTC) in a pre-menopausal woman: late sequelae of a traumatic event?

Background

“Tako-Tsubo cardiomyopathy” (TTC) is a syndrome characterized by left ventricular (LV) wall motion abnormalities, usually without coronary artery disease, mimicking the diagnosis of acute coronary syndrome. It most often affects post-menopausal women and TTC tends to run a benign course with very low rates of recurrence, complications or mortality. The condition is also called “stress-induced cardiomyopathy” because acute physical or emotional stress appears to be frequently related to its onset. The pathogenic role of premorbid or comorbid psychiatric illnesses has been discussed controversially. For the first time, we present a case of fourfold recurrent TTC with severe complications in a pre-menopausal woman. Furthermore, a long history of flaring posttraumatic stress symptoms anteceded the first event.

Case presentation

A 43-year old, pre-menopausal Caucasian woman was hospitalized with symptoms of acute coronary syndrome. Clinical examination revealed hypokinetic wall motion in the apical ventricular region with no signs of coronary artery disease and diagnosis of TTC was established. She experienced recurrence three times within the following ten months, which led to thrombembolism and myocardial scarring among others. The circumstances of chronic distress were striking. 16 years ago she miscarried after having removed a myoma according to her doctor’s suggestion. Since then, she has suffered from symptoms of posttraumatic distress which peaked annually at the day of abortion. Chronic distress became even more pronounced after the premature birth of a daughter some years later. The first event of TTC occurred after a family dispute about parenting.

Conclusion

This is the first case report of fourfold TTC in a pre-menopausal woman. From somatic perspectives, the course of the disease with recurrences and complications underlines the fact that TTC is not entirely benign. Furthermore, it is the first case report of long lasting symptoms of traumatic stress anteceding TTC. Close connections between adrenergic signaling and late onset of clinical stress symptoms are well known in the psychopathology of traumatization. Although larger clinical trials are needed to elucidate possible interactions of premorbid psychiatric illnesses and TTC, cardiologists should be vigilant especially in cases of recurrent TTC.

Anxiety sensitivity: changes with puberty and cardiovascular variables

BACKGROUND

Anxiety sensitivity (AS) is a relatively stable dispositional variable that may increase the risk for anxiety-related symptoms, particularly panic attack, among individuals of all age groups. Changes in AS during adolescence in healthy individuals, however, has not been previously investigated. The aim of this study was therefore to investigate the relationship of AS with puberty level, pulse rate, and blood pressure in healthy adolescents.

METHODS

The sample consisted of 133 healthy adolescents (70 boys, 63 girls) aged 10-17 years. Puberty stage (i.e. Tanner stage), pulse rate, and blood pressure of each participant were determined. The Childhood Anxiety Sensitivity Inventory was used to identify AS. The correlations between AS and the clinical variables were assessed.

RESULTS

AS was negatively correlated with pubertal stage when age and gender were controlled. Also, AS was correlated with diastolic blood pressure when age, gender, and pubertal stage were controlled (P < 0.05). Neither systolic blood pressure nor heart rate were correlated with AS.

CONCLUSION

AS, which is reported to be a trait-like variable, may change during adolescence, due to the effect of pubertal growth and blood pressure interacting with AS during adolescence.

Everything Hertz: methodological issues in short-term frequency-domain HRV

Frequency analysis of the electrocardiographic RR interval is a common method of quantifying autonomic outflow by measuring the beat-to-beat modulation of the heart (heart rate variability; HRV). This review identifies a series of problems with the methods of doing so—the interpretation of low-frequency spectral power, the multiple use of equivalent normalized low frequency (LFnu), high frequency (HFnu) and ratio (LF/HF) terms, and the lack of control over extraneous variables, and reviews research in the calendar year 2012 to determine their prevalence and severity. Results support the mathematical equivalency of ratio units across studies, a reliance on those variables to explain autonomic outflow, and insufficient control of critical experimental variables. Research measurement of HRV has a substantial need for general methodological improvement.

Anxiety Disorders are Associated with Reduced Heart Rate Variability: A Meta-Analysis

BACKGROUND

Anxiety disorders increase risk of future cardiovascular disease (CVD) and mortality, even after controlling for confounds including smoking, lifestyle, and socioeconomic status, and irrespective of a history of medical disorders. While impaired vagal function, indicated by reductions in heart rate variability (HRV), may be one mechanism linking anxiety disorders to CVD, prior studies have reported inconsistent findings highlighting the need for meta-analysis.

METHOD

Studies comparing resting-state HRV recordings in patients with an anxiety disorder as a primary diagnosis and healthy controls were considered for meta-analysis.

RESULTS

Meta-analyses were based on 36 articles, including 2086 patients with an anxiety disorder and 2294 controls. Overall, anxiety disorders were characterized by lower HRV [high frequency (HF): Hedges' g = -0.29. 95% CI: -0.41 to -0.17, p < 0.001; time domain: Hedges' g = -0.45, 95% CI: -0.57 to -0.33, p < 0.001] than controls. Panic disorder (n = 447), post-traumatic stress disorder (n = 192), generalized anxiety disorder (n = 68), and social anxiety disorder (n = 90), but not obsessive-compulsive disorder (n = 40), displayed reductions in HF HRV relative to controls (all ps < 0.001).

CONCLUSION

Anxiety disorders are associated with reduced HRV, findings associated with a small-to-moderate effect size. Findings have important implications for future physical health and well-being of patients, highlighting a need for comprehensive cardiovascular risk reduction.

Methylation of the SLC6a2 gene promoter in major depression and panic disorder

Reduced function of the noradrenaline transporter (NET) has been demonstrated in patients with major depressive disorder (MDD) and panic disorder. Attempts to explain NET dysfunction in MDD and panic disorder by genetic variation in the NET gene SLC6a2 have been inconclusive. Transcriptional silencing of the SLC6a2 gene may be an alternative mechanism which can lead to NET dysfunction independent of DNA sequence. The objective of this study was to characterise the DNA methylation state of the SLC6a2 gene promoter in patients with MDD and panic disorder. SLC6a2 promoter methylation was also analysed before and after antidepressant treatment. This study was performed with DNA from blood, using bisulphite sequencing and EpiTYPER methylation analyses. Patients with MDD or panic disorder were not found to differ significantly from healthy controls in the pattern of methylation of the SLC6a2 gene promotor. While significant correlations between methylation levels at some CpG sites and physiological measures were identified, overall the variation in DNA methylation between patients was small, and the significance of this variation remains equivocal. No significant changes in SLC6a2 promoter methylation were observed in response to antidepressant treatment. Further in-depth analysis of alternative mechanisms of transcriptional regulation of the SLC6a2 gene in human health and disease would be of value.

Circadian blood pressure variation in normotensive patients with panic disorder

Nondipper pattern of blood pressure (BP) is associated with cardiovascular risk. In this study, we compared dipper versus nondipper patterns between normotensive patients with panic disorder (PD) and a control group. A total of 25 normotensive patients with PD and 25 controls were enrolled. Twenty-four-hour ambulatory BP monitoring was performed in all patients. At least 10% of sleep-related nocturnal decrease in systolic and diastolic BP was accepted as dipper status, while decreases <10% were defined as a nondipper. Patients with PD had significantly higher incidence of nondipper BP pattern than controls. The reduction of nighttime BP in both systolic and diastolic and mean BP was significantly lower in patients with PD than in the control group (7.6% ± 4.3% vs 13% ± 3.9%, P < .001; 11% ± 7% vs 15% ± 5%, P = .004; 9% ± 5% vs 14% ± 4%, P = .002, respectively). Panic disorder is associated with nondipper BP pattern, causing impaired circadian BP in normotensive settings.

Decreased cardiac vagal control in drug-naive patients with panic disorder: a case-control study in Taiwan

INTRODUCTION

Cardiac autonomic dysregulation has been proposed in panic disorder (PD), but the results are mixed. Analyses with larger sample sizes and better methodology are needed.

METHODS

Forty-eight drug-naïve individuals with PD and 202 healthy volunteers were recruited for a case-control analysis. We used the Hamilton Anxiety Rating Scale and the Beck Anxiety Inventory to assess anxiety severity. Cardiac autonomic function was evaluated by measuring heart rate variability (HRV) parameters. Frequency-domain indices of HRV were obtained. The obtained results were evaluated in association with personality traits assessed by the Tridimensional Personality Questionnaire.

RESULTS

Patients exhibited reduced mean RR interval (816.94 ± 135.92 versus 873.47 ± 143.36 ms, P = 0.014) and HRV levels (Var 6.37 ± 1.32 versus 7.38 ± 0.95, LF 4.90 ± 1.63 versus5.82 ± 1.11 and HF 4.57 ± 1.53 versus 5.62 ± 1.24 [ln(ms2)], all P < 0.001) as compared to controls, which mainly suggested a reduction in cardiac vagal control in PD. The anxiety severity was negatively correlated with HRV levels (r = -0.29 for Var, r = -0.22 for LF and r = -0.28 for HF, all P < 0.001). The harm avoidance score (which has been suggested to be associated with serotonergic activity) was associated with decreased HRV levels (r = -0.22 for Var, P < 0.01, r = -0.14 for LF, P < 0.05 and r = -0.17 for HF, P < 0.01).

DISCUSSION

This study demonstrates that PD is associated with cardiac autonomic dysregulation, highlighting the importance of assessing HRV in PD patients.