A neuroimmunological perspective on anxiety disorders

Association of short-term exposure to ambient fine particulate matter and ozone with outpatient visits for anxiety disorders: A hospital-based case-crossover study in South China

BACKGROUND

The short-term adverse effects of ambient fine particulate matter (PM2.5) and ozone (O3) on anxiety disorders (ADs) remained inconclusive.

METHODS

We applied an individual-level time-stratified case-crossover study, which including 126,112 outpatient visits for ADs during 2019-2021 in Guangdong province, China, to investigate the association of short-term exposure to PM2.5 and O3 with outpatient visits for ADs, and estimate excess outpatient visits in South China. Daily residential air pollutant exposure assessments were performed by extracting grid data (spatial resolution: 1 km × 1 km) from validated datasets. We employed the conditional logistic regression model to quantify the associations and excess outpatient visits.

RESULTS

The results of the single-pollutant models showed that each 10 μg/m3 increase of PM2.5 and O3 exposures was significantly associated with a 3.14 % (95 % confidence interval: 2.47 %, 3.81 %) and 0.88 % (0.49 %, 1.26 %) increase in odds of outpatient visits for ADs, respectively. These associations remained robust in 2-pollutant models. The proportion of outpatient visits attributable to PM2.5 and O3 exposures was up to 7.20 % and 8.93 %, respectively. Older adults appeared to be more susceptible to PM2.5 exposure, especially in cool season, and subjects with recurrent outpatient visits were more susceptible to O3 exposure.

LIMITATION

As our study subjects were from one single hospital in China, it should be cautious when generalizing our findings to other regions.

CONCLUSION

Short-term exposure to ambient PM2.5 and O3 was significantly associated with a higher odds of outpatient visits for ADs, which can contribute to considerable excess outpatient visits.

Salivary CRP predicts treatment response to virtual reality exposure therapy for social anxiety disorder

BACKGROUND

Social anxiety disorder (SAD) places a profound burden on public health and individual wellbeing. Systemic inflammation may be important to the onset and maintenance of SAD, and anti-inflammatory treatments have shown promise in relieving symptoms of SAD. In the present study, we conducted secondary analyses on data from a randomized clinical trial to determine whether C-reactive protein (CRP) concentrations and social anxiety symptoms decreased over the course of virtual reality exposure therapy, and whether changes in social anxiety symptoms as a function of treatment varied as a function of CRP.

METHOD

Adult participants (N = 78) with a diagnosis of SAD (59 % female) were randomized to receive exposure therapy alone, or exposure therapy supplemented with scopolamine. Social anxiety symptoms, salivary CRP, and subjective units of distress were measured across three exposure therapy sessions, at a post-treatment extinction retest, and at a 1-month follow-up.

RESULTS

CRP decreased over the course of treatment, b = -0.03 (SE = 0.01), p =.02 95 %CI [-0.06, -0.004], as did all social anxiety symptom domains and subjective distress. Higher CRP was associated with greater decreases from pre-treatment to 1-month follow-up in fear, b = -0.45 (SE = 0.15), p =.004 95 %CI [-0.74, -0.15], and avoidance, b = -0.62 (SE = 0.19), p =.002 95 %CI [-1.01, -0.23], and in-session subjective distress from pre-treatment to post-treatment, b = -0.42 (SE = 0.21), p =.05 95 %CI [-0.83, -0.001]. However, declines in CRP were not correlated with declines in fear, r = -0.07, p =.61, or avoidance, r = -0.10, p =.49, within-persons.

CONCLUSIONS

Virtual reality exposure therapy may be associated with an improvement in systemic inflammation in patients with severe SAD. Pre-treatment CRP may also be of value in predicting which patients stand to benefit the most from this treatment.

Daytime aspartame intake results in larger influences on body weight, serum corticosterone level, serum/cerebral cytokines levels and depressive-like behaviors in mice than nighttime intake

Aspartame (APM) is one of the most widely used artificial sweeteners worldwide. Studies have revealed that consuming APM may negatively affect the body, causing oxidative stress damage to multiple organs and leading to various neurophysiological symptoms. However, it's still unclear if consuming APM and one's daily biological rhythm have an interactive effect on health. In this study, healthy adult C57BL/6 mice were randomly divided into four groups: Control group (CON), oral gavage sham group (OGS), daytime APM intragastric group (DAI) and nighttime APM intragastric group (NAI). DAI and NAI groups were given 80 mg/kg body weight daily for 4 weeks. We found that DAI and NAI groups had significantly increased mean body weight, higher serum corticosterone levels, up-regulated pro-inflammatory responses in serum and brain, and exacerbated depressive-like behaviors than the CON and the two APM intake groups. Moreover, all these changes induced by APM intake were more significant in the DAI group than in the NAI group. The present study, for the first time, revealed that the intake of APM and daily biological rhythm have an interactive effect on health. This suggests that more attention should be paid to the timing of APM intake in human beings, and this study also provides an intriguing clue to the circadian rhythms of experimental animals that researchers should consider more when conducting animal experiments.

Overexpression of the schizophrenia risk gene C4 in PV cells drives sex-dependent behavioral deficits and circuit dysfunction

Fast-spiking parvalbumin (PV)-positive cells are key players in orchestrating pyramidal neuron activity, and their dysfunction is consistently observed in myriad brain diseases. To understand how immune complement dysregulation - a prevalent locus of brain disease etiology - in PV cells may drive disease pathogenesis, we have developed a transgenic mouse line that permits cell-type specific overexpression of the schizophrenia-associated complement component 4 (C4) gene. We found that overexpression of mouse C4 (mC4) in PV cells causes sex-specific behavioral alterations and concomitant deficits in synaptic connectivity and excitability of PV cells of the prefrontal cortex. Using a computational network, we demonstrated that these microcircuit deficits led to hyperactivity and disrupted neural communication. Finally, pan-neuronal overexpression of mC4 failed to evoke the same deficits in behavior as PV-specific mC4 overexpression, suggesting that C4 perturbations in fast-spiking neurons are more harmful to brain function than pan-neuronal alterations. Together, these results provide a causative link between C4 and the vulnerability of PV cells in brain disease.

Serum proteomics analysis of drug-naïve patients with generalised anxiety disorder: Tandem mass tags and multiple reaction monitoring

OBJECTIVES

The prevalence of generalised anxiety disorder (GAD) is high. However, the underlying mechanisms remain elusive. Proteomics techniques can be employed to assess the pathological mechanisms involved in GAD.

METHODS

Twenty-two drug-naive GAD patients were recruited, their serum samples were used for protein quantification and identified using Tandem Mass Tag and Multiple Reaction Monitoring (MRM). Machine learning models were employed to construct predictive models for disease occurrence by using clinical scores and target proteins as input variables.

RESULTS

A total of 991 proteins were differentially expressed between GAD and healthy participants. Gene Ontology analysis revealed that these proteins were significantly associated with stress response and biological regulation, suggesting a significant implication in anxiety disorders. MRM validation revealed evident disparities in 12 specific proteins. The machine learning model found a set of five proteins accurately predicting the occurrence of the disease at a rate of 87.5%, such as alpha 1B-glycoprotein, complement component 4 A, transferrin, V3-3, and defensin alpha 1. These proteins had a functional association with immune inflammation.

CONCLUSIONS

The development of generalised anxiety disorder might be closely linked to the immune inflammatory stress response.

Minocycline as a potential anxiolytic drug: systematic review and meta-analysis of evidence in murine models

Minocycline is a tetracycline antibiotic with off-label use as an anti-inflammatory drug. Because it can cross the blood-brain barrier, minocycline has been proposed as an alternative treatment for psychiatric disorders, in which inflammation plays an important role. However, its beneficial effects on anxiety disorders are unclear. Therefore, we performed a systematic review and meta-analysis to evaluate the efficacy of minocycline as an anxiolytic drug in preclinical models. We performed a PubMed search according to the PRISMA guidelines and PICOS strategy. The risk of bias was evaluated using the SYRCLE tool. We included studies that determined the efficacy of minocycline in animal models of anxiety that may involve exposures (e.g. stressors, immunomodulators, injury). Data extracted included treatment effect, dose range, route of administration, and potential mechanisms for the anxiolytic effect. Meta-analysis of twenty studies showed that minocycline reduced anxiety-like behavior in rodents previously exposed to stress or immunostimulants but not in exposure-naïve animals. This effect was not associated with the dose administered or treatment duration. The mechanism for the anxiolytic activity of minocycline may depend on its anti-inflammatory effects in the brain regions involving anxiety. These suggest that minocycline could be repurposed as a treatment for anxiety and related disorders and warrants further evaluation.

Internalizing disorders as a mediator of the association between adverse childhood experiences and perceived medication intolerance or poly-allergy

OBJECTIVES

There is a well-established link between adverse childhood events, mental health, and physical health conditions. There is also a large literature showing the relationship between medication intolerance or allergies, and poor health outcomes. However, less is understood about the role of medication intolerance and adverse childhood events. Thus, the present study examines the relationship between adverse childhood events, internalizing disorders (depression, anxiety) and medication intolerance.

METHOD

Three hundred forty-nine participants were recruited from 11 primary care practices and health networks located in a large, Midwestern metropolitan area. Unrelated linear and Poisson regression was used to determine whether internalizing disorders, such as depression and anxiety, mediated the relationship between adverse childhood experiences (ACEs) and allergies to medications, accounting for error terms in regression equations that were correlated.

RESULTS

Results indicated an association between ACEs and number of allergies to medication, whereby ACEs was associated with depression, anxiety and number of allergies. Sensitivity analysis confirmed these findings. There was a small but significant indirect effect of anxiety on allergies to medication after bootstrapping.

CONCLUSION

This study found that inflammatory responses occurring because of trauma and depression may be increasing medication allergies. However, given the size of the sample, more research is needed to confirm these results. Implications for healthcare providers are discussed.

Fenofibrate Decreases Ethanol-Induced Neuroinflammation and Oxidative Stress and Reduces Alcohol Relapse in Rats by a PPAR-α-Dependent Mechanism

High ethanol consumption triggers neuroinflammation, implicated in sustaining chronic alcohol use. This inflammation boosts glutamate, prompting dopamine release in reward centers, driving prolonged drinking and relapse. Fibrate drugs, activating peroxisome proliferator-activated receptor alpha (PPAR-α), counteract neuroinflammation in other contexts, prompting investigation into their impact on ethanol-induced inflammation. Here, we studied, in UChB drinker rats, whether the administration of fenofibrate in the withdrawal stage after chronic ethanol consumption reduces voluntary intake when alcohol is offered again to the animals (relapse-type drinking). Furthermore, we determined if fenofibrate was able to decrease ethanol-induced neuroinflammation and oxidative stress in the brain. Animals treated with fenofibrate decreased alcohol consumption by 80% during post-abstinence relapse. Furthermore, fenofibrate decreased the expression of the proinflammatory cytokines tumor necrosis factor-alpha (TNF-α) and interleukins IL-1β and IL-6, and of an oxidative stress-induced gene (heme oxygenase-1), in the hippocampus, nucleus accumbens, and prefrontal cortex. Animals treated with fenofibrate showed an increase M2-type microglia (with anti-inflammatory proprieties) and a decrease in phagocytic microglia in the hippocampus. A PPAR-α antagonist (GW6471) abrogated the effects of fenofibrate, indicating that they are dependent on PPAR-α activation. These findings highlight the potential of fenofibrate, an FDA-approved dyslipidemia medication, as a supplementary approach to alleviating relapse severity in individuals with alcohol use disorder (AUD) during withdrawal.

The role of inflammation in anxiety and depression in the European U-BIOPRED asthma cohorts

BACKGROUND

Growing evidence indicates high comorbid anxiety and depression in patients with asthma. However, the mechanisms underlying this comorbid condition remain unclear. The aim of this study was to investigate the role of inflammation in comorbid anxiety and depression in three asthma patient cohorts of the Unbiased Biomarkers for the Prediction of Respiratory Disease Outcomes (U-BIOPRED) project.

METHODS

U-BIOPRED was conducted by a European Union consortium of 16 academic institutions in 11 European countries. A subset dataset from subjects with valid anxiety and depression measures and a large blood biomarker dataset were analysed, including 198 non-smoking patients with severe asthma (SAn), 65 smoking patients with severe asthma (SAs), 61 non-smoking patients with mild-to-moderate asthma (MMA), and 20 healthy non-smokers (HC). The Hospital Anxiety and Depression Scale was used to measure anxiety and depression and a series of inflammatory markers were analysed by the SomaScan v3 platform (SomaLogic, Boulder, Colo). ANOVA and the Kruskal-Wallis test were used for multiple-group comparisons as appropriate.

RESULTS

There were significant group effects on anxiety and depression among the four cohort groups (p < 0.05). Anxiety and depression of SAn and SAs groups were significantly higher than that of MMA and HC groups (p < 0.05. There were significant differences in serum IL6, MCP1, CCL18, CCL17, IL8, and Eotaxin among the four groups (p < 0.05). Depression was significantly associated with IL6, MCP1, CCL18 level, and CCL17; whereas anxiety was associated with CCL17 only (p < 0.05).

CONCLUSIONS

The current study suggests that severe asthma patients are associated with higher levels of anxiety and depression, and inflammatory responses may underlie this comorbid condition.

Pharmacological Treatment of Generalised Anxiety Disorder: Current Practice and Future Directions

INTRODUCTION

Generalized Anxiety Disorder (GAD) is a common psychiatric condition, characterized by the presence of general apprehensiveness and excessive worry. Current management consists of a range of pharmacological and psychological treatments. However, many patients do not respond to first-line pharmacological treatments and novel anxiolytic drugs are being developed.

AREAS COVERED

In this review, the authors first discuss the diagnostic criteria and epidemiology of GAD. The effective pharmacological treatments for GAD and their tolerability are addressed. Current consensus guidelines for treatment of GAD are discussed, and maintenance treatment, the management of treatment resistance, and specific management of older adults and children/adolescents are considered. Finally, novel anxiolytics under development are discussed, with a focus on those which have entered clinical trials.

EXPERT OPINION

A range of effective treatments for GAD are available, particularly duloxetine, escitalopram, pregabalin, quetiapine, and venlafaxine. There is a limited evidence base to support the further pharmacological management of patients with GAD who have not responded to initial treatment. Although many novel anxiolytics have progressed to clinical trials, translation from animal models has been mostly unsuccessful. However, the potential of several compounds including certain psychedelics, ketamine, oxytocin, and agents modulating the orexin, endocannabinoid, and immune systems merits further study.

Psychiatric symptomatology in skin-restricted lupus patients without axis I psychiatric disorders: A post-hoc analysis

BACKGROUND

Skin-restricted lupus is a chronic inflammatory disease associated with high rates of depression and anxiety disorders. Patients without psychiatric disorders can experience anxiety and depressive symptoms at a subclinical level, which could be risk factors for progression towards psychiatric disorders. It was decided, therefore, to investigate the presence of specific symptoms in skin-restricted lupus patients without axis I psychiatric disorders and their impact on the occurrence of axis I psychiatric disorders during the study follow-up.

METHODS

Longitudinal data of 38 patients and 76 matched controls without active axis I psychiatric disorders from the LuPsy cohort were used. Depressive, neurovegetative, psychic and somatic anxiety symptom scores were established from the Montgomery-Asberg Depression Rating Scale (MADRS) and the Hamilton Anxiety Rating scale (HAMA).

RESULTS

None of the participants had any current active axis I psychiatric disorders but the patients had personality disorders more frequently and had received more past psychotropic treatments than the controls. They also had higher MADRS and HAMA scores than the controls, in particular neurovegetative, psychic anxiety and somatic symptoms scores. No dermatological factor tested was associated with these scores, whereas being a lupus patient was associated with higher neurovegetative and somatic symptoms scores, having a current personality disorder with higher depressive and neurovegetative scores and receiving more past psychotropic treatments with psychic anxiety and somatic symptoms scores. The occurrence of psychiatric disorders during the study follow-up was associated with an elevated psychic anxiety score at baseline and past psychotropic treatment but not with history of psychiatric disorder.

LIMITATIONS

The LuPsy cohort included a large number of patients with axis I psychiatric disorders, the sample without axis I psychiatric disorders is therefore limited.

CONCLUSIONS

We observed numerous psychiatric symptoms among the skin-restricted lupus patients. They should therefore receive special attention in the management of their subclinical symptoms before they progress towards full psychiatric disorders.

Desulfovibrio confers resilience to the comorbidity of pain and anxiety in a mouse model of chronic inflammatory pain

BACKGROUND

Patients with chronic pain frequently suffer from anxiety symptoms. It has been well established that gut microbiota is associated with the pathogenesis of pain and anxiety. However, it is unknown whether the gut microbiota, particularly the specific bacteria, play a role in the comorbidity of chronic pain and anxiety.

METHODS

Chronic inflammatory pain was induced in mice by a single injection of complete Freund's adjuvant (CFA). Mice were then separated into anxiety-susceptible and anxiety-resilient phenotypes by hierarchical clustering analysis of behaviors. Fecal samples were collected to perform 16S rRNA gene sequencing. Chronic diazepam intervention served as a therapeutic strategy and its effect on the composition of gut microbiota was also determined.

RESULTS

α-Diversity and β-diversity both showed significant differences among the groups. A total of 12 gut bacteria were both altered after CFA injection and reversed by chronic diazepam treatment. More importantly, the pain hypersensitivity and anxiety-like behaviors were relieved by chronic diazepam treatment. Interestingly, we also found that Desulfovibrio was increased in anxiety-resilient group compared to control and anxiety-susceptible groups.

CONCLUSION

Abnormal composition of gut microbiota plays an essential role in chronic pain as well as in anxiety. Besides, the increased level of Desulfovibrio in anxiety-resilient mice indicated its therapeutic effects on the comorbidity of pain and anxiety. Collectively, targeting gut microbiota, especially increasing the Desulfovibrio level, might be effective in the alleviation of chronic pain-anxiety comorbidity.

Anxiety and coping strategies during the COVID-19 pandemic: A cross-sectional study of staff and students from a tertiary education center in Malaysia

Aim

We examined the anxiety levels and coping strategies among staff and students of a tertiary educational institution during the COVID-19 pandemic and determined the association between anxiety level and coping strategies.

Method

Through an online survey, we used Coronavirus Anxiety Scale (CAS) to measure the level of anxiety associated with the COVID-19 crisis and Brief Coping Orientation to Problems Experienced (COPE) to assess the coping responses adopted to handle stressful life events. Coping strategies were classified as adaptive and maladaptive, for which the aggregate sores were calculated. Multiple linear regression was used to determine the predictors of anxiety adjusted for potentially confounding variables. Results from 434 participants were available for analysis.

Results

The mean score (SD) of the CAS was 1.1 (1.8). The mean scores of adaptive and maladaptive coping strategies were 35.69 and 19.28, respectively. Multiple linear regression revealed that maladaptive coping [Adjusted B coefficient = 4.106, p-value < 0.001] and presence of comorbidities [Adjusted B coefficient = 1.376, p-value = 0.025] significantly predicted anxiety.

Conclusion

Maladaptive coping and presence of comorbidities were the predictors of coronavirus anxiety. The apparent lack of anxiety in relation to COVID-19 and movement restriction is reflective of the reported high level of satisfaction with the support and services provided during the COVID-19 outbreak in Malaysia. Adaptive coping strategies were adopted more frequently than maladaptive. Nevertheless, public education on positive coping strategies and anxiety management may be still be relevant to provide mental health support to address the needs of the general population.

Association between traffic-related air pollution and anxiety hospitalizations in a coastal Chinese city: are there potentially susceptible groups?

Motor vehicle exhaust emissions have become the main source of urban air pollution in China, but few studies have explored the association of short-term exposure to traffic-related air pollutants (TRAPs) with anxiety disorders. Thus, we used an overdispersed, generalized additive model (GAM) to investigate the association between TRAPs and hospital admissions (HAs) for anxiety in Qingdao, a coastal Chinese city with high vehicle ownership. In addition, stratified analyses were performed by gender, age, season and hospitalization frequency (first admission and readmission). A positive association between TRAPs and HAs for anxiety was observed. Both inhalable particulate matter (PM₁₀) and nitrogen dioxide (NO₂) showed significant effects at lag 3 in the single-day lag structure, and each 10 μg/m³ increase in the concentrations was significantly associated with increases of 0.88% [95% confidence interval (CI): 0.04%, 1.72%] for PM₁₀ and 2.74% (0.45%, 5.08%) for NO₂ on anxiety hospitalizations. For fine particulate matter (PM_2.5) and carbon monoxide (CO), the strongest effects were found at lag05 and lag04 [2.67% (0.77%, 4.62%) and 0.19% (0.04%, 0.34%), respectively] in the multiday lag structure. The estimates of PM_2.5 were relatively robust after adjusting for other pollutants in the two-pollutant model. Stratified analyses indicated that the associations were stronger in females and younger individuals (<45 in age) than in males and elderly individuals (≥45 in age). Furthermore, the effects of PM_2.5 and CO were most obvious during the cold season. Regarding hospitalization frequency, only PM_2.5 was found to have a significant effect in the first-admission group. The results showed that short-term exposure to TRAPs, especially to PM_2.5, was significantly associated with the increased risk of daily HAs for anxiety, which can help clinicians and policymakers better understand the effects of TRAPs to implement targeted interventions.

Fostering emotional self-regulation in female teachers at the public teaching network: A mindfulness-based intervention improving psychological measures and inflammatory biomarkers

OBJECTIVE

To examine the effect of a mindfulness-based program specifically designed for teachers in reducing perceived stress and improving the quality of experienced emotion in female active working teachers. A second outcome evaluated is the associated change in cellular inflammatory activity, measured by peripheral blood levels of cytokines.

METHOD

Eighty-eight female active teachers from public schools from São Paulo Municipality were recruited, and randomly allocated to an eight-week Mindfulness-Based Health Program for Educators (MBHP-Educa) or to Neuroscience for Education Program (Neuro-Educa: active control group). The venue of both programs were several public school facilities, where many of the teachers actually worked. Both groups received activities during eight weeks in a 2 ​h/week regimen, totalizing 16 ​h. Sixty-five participants completed the program and pre- and post-interventions measures were taken from the following scales: Interpersonal Multidimensional Reactivity Scale (IRI), Positive-and-Negative Affects Scale (PANAS), Perceived Stress Scale (PSS), Connor-Davidson Resilience Scale (CD-RISC), and a primary outcome in Ryff's Psychological Well-Being Scale (PBWS). At pre-and post-intervention, blood samples were collected for the measurement of several important inflammatory biomarkers, Tumor Necrosis Factor - α (TNF-α), Interleukin 1β (IL-1β), Interleukin 6 (IL-6), Interleukin 8 (IL-8), Interleukin 10 (IL-10) and Interleukin 12p70 (IL-12P70) through flow cytometry assay. Intervention effects were analyzed via Generalized mixed models (GLMM).

RESULTS

According to the GLMM, MBHP-Educa significantly reduced the scores of perceived stress (p ​< ​0.0001), and negative affect (p ​< ​0.0001) compared to active control group (Neuro-Educa). Conversely, an increase was observed on Psychological Well Being Scale in dimensions of Self-acceptance (p ​< ​0.0001), and Autonomy (p ​= ​0.001), as well as improvements in Resilience (p ​< ​0.0001), and Positive Affect (p ​< ​0.0001). MBHP-Educa also promoted a reduction in the levels of IL-6 (p ​= ​0.003), IL-8 (p ​= ​0.036), and increase in the levels of IL-10 (p ​< ​0.0001) and IL-12p70 (p ​< ​0.044). TNF-α, IL-1β, and IL-10p70 showed results below theoretical limit of detection accepted for CBA kit.

CONCLUSIONS

Our data suggest that mindfulness-based interventions introduced as a strategy for reducing stress, promoting well-being and improve immune function can be a useful asset in promoting psychological health among teachers in Basic Education.

Association of using biomass fuel for cooking with depression and anxiety symptoms in older Chinese adults

BACKGROUNDS

Household air pollution exposure is a crucial public concern and have the potential to seriously affect human health. Using biomass fuels for cooking is the main contributor to household air pollution. However, current evidence linked between cooking with biomass fuels and mental health remains limited.

OBJECTIVES

To explore whether cooking with biomass fuels is associated with depression and anxiety symptoms among older adults in China.

METHODS

We obtained data from Chinese Longitudinal Healthy Longevity Survey (CLHLS). Depressive and anxiety symptoms were assessed using the 10-item Center for Epidemiologic Studies Depression Scale (CES-D-10) and the 7-item Generalized Anxiety Disorder Scale (GAD-7), respectively. Primary cooking fuel type was self-reported. We used logistic regression and linear regression to evaluate the effects of cooking with biomass fuels on depression and anxiety.

RESULTS

A total of 13,361 participants aged 65 years and older (mean age, 84.2 ± 11.5 years) were included in the presented study. A positive association was found between cooking with biomass fuels and both depression symptoms (adjusted odds ratio 1.23, 95% CI 1.03 to 1.47) and anxiety symptoms (adjusted odds ratio 1.31, 95% CI 1.02 to 1.68). Biomass fuel users had a higher depression scores (0.33, 95% CI 0.03 to 0.61) and a higher anxiety scores (0.20, 95% CI 0.02 to 0.38) compared to clean fuel users. We found no significant interactions between participant characteristics and biomass fuel use on either depression or anxiety symptoms.

CONCLUSIONS

Cooking with biomass fuels was associated with depression and anxiety symptoms in order adults. Further large prospective cohort studies are warranted to confirm this association.

Influence of Simvastatin as Augmentative Therapy in the Treatment of Generalized Anxiety Disorder: A Pilot Randomized, Placebo-Controlled Study

BACKGROUND

Preliminary evidence is promising regarding the anxiolytic effects of statins in animal models of anxiety. Hence, this study aimed to evaluate the efficacy of simvastatin augmentation versus placebo in the treatment of patients with generalized anxiety disorder (GAD) with residual symptoms despite treatment with selective serotonin reuptake inhibitors (SSRIs).

METHODS

A double-blind, 8-week controlled trial was conducted from August 2018 to December 2019 in an outpatient psychiatry clinic in Hamadan, Iran. A total of 138 patients with a diagnosis of GAD were assessed for eligibility. Of them, 84 patients who met the study criteria were randomly assigned either to the adjuvant simvastatin (20 mg/day) or to the placebo group. Standard medication consisting of SSRIs was consistent 2 months prior to and during the study. The severity of anxiety symptoms for each patient was assessed based on the Hamilton Anxiety Rating Scale (HAM-A) score at baseline, week 4, and week 8 after treatment. Additionally, blood lipid values were assessed at baseline and on completion of the study.

RESULTS

Thirty-three out of 42 patients in the intervention group and 35 out of 42 patients in the control group completed the 8 weeks of the study period. Compared to the placebo group, in the simvastatin group cholesterol, triglycerides, and low-density lipoprotein significantly decreased, and high-density lipoprotein significantly increased over time. General linear model analysis demonstrated that although over time a higher decrease in mean HAM-A scores was observed in the intervention group compared to the control group, this difference was not statistically significant (p = 0.11). In addition, at the end of the study, the number of responders and remitters was comparable in the two groups.

CONCLUSIONS

The results from this clinical study did not support the potential efficacy of adjunctive simvastatin in the treatment of patients with GAD. Thus, large-scale and long-term clinical trials are required to more accurately assess the potential efficacy of statins in the treatment of patients with anxiety disorders.

Psychological distress after subarachnoid haemorrhage: A systematic review and meta-analysis

OBJECTIVE

Psychological distress is a common complication in patients after Subarachnoid haemorrhage (SAH) which often has significant impact on the prognosis. The objective of this study was to determine the pooled prevalence of anxiety symptoms and depressive symptoms in patients after SAH and identify relevant risk factors.

METHODS

The study adopted a systematic review and meta-analysis protocol. Multiple databases including EMBASE, Medline, PsychInfo, and Web of Science were searched for publications before 1st January 2020. Screening, data extraction, and quality assessment were undertaken following the PRISMA guidelines for preferred reporting of systematic reviews and meta-analysis. The random-effects model was used to calculate pooled prevalence rates. Meta-analysis was conducted using Comprehensive Meta-analysis software. The review protocol was registered on PROSPERO (CRD42020182594).

RESULTS

42 studies reporting anxiety symptoms and 64 studies reporting depressive symptoms were included. The pooled short term(<3 years) and long term(≥3 years) prevalence rates of anxiety symptoms were 31.4%(95% CI: 23.6%, 40.4%) and 40.4%(95% CI: 31.6%, 49.8%), respectively, whereas the pooled short term and long term prevalence rates of depressive symptoms were 25.2%(95%CI: 17.8%, 34.5%) and 35.8%(95%CI: 28.6%, 43.6%), respectively. Gender and pre-existing psychiatric conditions were identified as potential risk factors.

CONCLUSIONS

The high prevalence of anxiety symptoms and depressive symptoms after SAH highlights the need for appropriate assessment and management of psychological stress in patients after SAH. Further research is warranted to explore potential underlying mechanisms and to develop holistic interventions that incorporate understanding of both the biological and psychological impact of SAH.

Early-life inflammation promotes depressive symptoms in adolescence via microglial engulfment of dendritic spines

Early-life inflammation increases the risk for depression in later life. Here, we demonstrate how early-life inflammation causes adolescent depressive-like symptoms: by altering the long-term neuronal spine engulfment capacity of microglia. For mice exposed to lipopolysaccharide (LPS)-induced inflammation via the Toll-like receptor 4/NF-κB signaling pathway at postnatal day (P) 14, ongoing longitudinal imaging of the living brain revealed that later stress (delivered during adolescence on P45) increases the extent of microglial engulfment around anterior cingulate cortex (ACC) glutamatergic neuronal (ACCGlu) spines. When the ACC microglia of LPS-treated mice were deleted or chemically inhibited, the mice did not exhibit depressive-like behaviors during adolescence. Moreover, we show that the fractalkine receptor CX3CR1 mediates stress-induced engulfment of ACCGlu neuronal spines. Together, our findings establish that early-life inflammation causes dysregulation of microglial engulfment capacity, which encodes long-lasting maladaptation of ACCGlu neurons to stress, thus promoting development of depression-like symptoms during adolescence.

Transcutaneous Auricular Vagus Nerve Stimulation Combined With Slow Breathing: Speculations on Potential Applications and Technical Considerations

OBJECTIVES

Transcutaneous auricular vagus nerve stimulation (taVNS) is a relatively novel noninvasive neurostimulation method that is believed to mimic the effects of invasive cervical VNS. It has recently been suggested that the effectiveness of taVNS can be enhanced by combining it with controlled slow breathing. Slow breathing modulates the activity of the vagus nerve and is used in behavioral medicine to decrease psychophysiological arousal. Based on studies that examine the effects of taVNS and slow breathing separately, this article speculates on some of the conditions in which this combination treatment may prove effective. Furthermore, based on findings from studies on the optimization of taVNS and slow breathing, this article provides guidance on how to combine taVNS with slow breathing.

MATERIALS AND METHODS

A nonsystematic review.

RESULTS

Both taVNS and slow breathing are considered promising add-on therapeutic approaches for anxiety and depressive disorders, chronic pain, cardiovascular diseases, and insomnia. Therefore, taVNS combined with slow breathing may produce additive or even synergistic beneficial effects in these conditions. Studies on respiratory-gated taVNS during spontaneous breathing suggest that taVNS should be delivered during expiration. Therefore, this article proposes to use taVNS as a breathing pacer to indicate when and for how long to exhale during slow breathing exercises.

CONCLUSIONS

Combining taVNS with slow breathing seems to be a promising hybrid neurostimulation and behavioral intervention.

Review: Inflammation and anxiety-based disorders in children and adolescents - a systematic review and meta-analysis

BACKGROUND

Anxiety-based disorders are common and are often chronic with an onset during childhood or adolescence. An emerging literature has examined the role of inflammation in these disorders by measuring blood concentrations of inflammatory markers such as cytokines, C-reactive protein (CRP) and immune markers such as white blood cell counts. However, existing results are inconsistent, with available meta-analyses only including adult populations. We believe this is the first systematic review and meta-analysis to investigate these inconsistencies among the population of children and adolescents.

METHODS

A systematic search of five electronic databases was conducted to identify studies which compared inflammatory markers between individuals with an anxiety-based disorder and healthy controls. Study quality was assessed, and pooled effect sizes (Hedges' g) were calculated using random-effects meta-analyses.

RESULTS

Nine independent studies were identified. The combined meta-analysis of 16 cytokines and CRP was approaching significance; however, no significant between-group difference was observed for meta-analyses of individual inflammatory or immune markers. Heterogeneity was high, and quality assessments identified important limitations; primarily, small sample sizes and a lack of control over confounding variables.

CONCLUSIONS

Although no significant effects were observed, the small number of included studies and limitations in study or reporting quality render these findings provisional. Research in this area has the potential for important clinical implications in relation to therapeutic interventions. Important recommendations for further research are put forth.

Dynamic Effects of CAM Techniques on Inflammation and Emotional States: An Integrative Single-Case Study on a Breast Cancer Survivor

BACKGROUND

This study on a breast cancer survivor investigated how episodic practice of various complementary and alternative medicine (CAM) techniques affected the dynamics of emotional states and urinary neopterin-an inflammation marker.

METHODS

The 49-year-old female patient (diagnosis: ductal breast carcinoma 5 years before study start, suffering from chronic fatigue and depression) collected her entire urine in 12-hour intervals (from about 8 a.m. to 8 p.m. and from about 8 p.m. to 8 a.m.) for 28 days. The resulting 55 consecutive urine samples were analyzed for neopterin and creatinine levels using HPLC. Also in 12-hour intervals, the patient filled out questionnaires on emotional states and everyday routine, including CAM practice. Weekly, she was interviewed to identify emotionally meaningful everyday incidents, including use of CAM techniques. Time series analysis consisted of ARIMA modeling and cross-correlational analyses.

RESULTS

Qualitative evaluation revealed that, with the exception of Tai Chi, all CAM techniques, that is, Jin Shin Jyutsu, music, physiotherapy and energy healing, were experienced as positive. Cross-correlational analyses showed that practice of such CAM techniques was followed first by significant (P < .05) increases in positive mood and mental activity on the same day (lag 0) and then by decreases in positive mood after a total of 72 to 84 hours (+lag 6) and in mental activity after a total of 84 to 96 hours (+lag 7). Negative mood, by contrast, first decreased on the day of CAM practice (lag 0) and then increased after a total of 84 to 96 hours (+lag 7) following CAM. Moreover, urinary neopterin levels first increased on the day of CAM practice (lag 0) and then decreased after a total of 36 to 48 hours (+lag 3). Similar biphasic effects were also detected for irritation in response to CAM, although only partly significant.

CONCLUSION

Cyclic psychophysiological response patterns following CAM practice were attributable to biopsychosocial feedback mechanisms involving personally meaningful experiences. As lower neopterin levels following CAM point to a health-promoting effect, the patient of this study may have actively contributed to her healing process through episodic CAM practice.

Treatment Response Biomarkers in Anxiety Disorders: From Neuroimaging to Neuronally-Derived Extracellular Vesicles and Beyond

Multiple and diverse psychotherapeutic or psychopharmacologic treatments effectively reduce symptoms for many patients with anxiety disorders, but the trajectory and magnitude of response vary considerably. This heterogeneity of treatment response has invigorated the search for biomarkers of treatment response in anxiety disorders, across the lifespan. In this review, we summarize evidence for biomarkers of treatment response in children, adolescents and adults with generalized, separation and social anxiety disorders as well as panic disorder. We then discuss the relationship between these biomarkers of treatment response and the pathophysiology of anxiety disorders. Finally, we provide context for treatment response biomarkers of the future, including neuronally-derived extracellular vesicles in anxiety disorders and discuss challenges that must be overcome prior to the debut of treatment response biomarkers in the clinic. A number of promising treatment response biomarkers have been identified, although there is an urgent need to replicate findings and to identify which biomarkers might guide clinicians in selecting from available treatments rather than just simply identifying patients who may be less likely to respond to a given intervention.

High-refined carbohydrate diet consumption induces neuroinflammation and anxiety-like behavior in mice

Consumption of poor nutrients diets is associated with fat tissue expansion and with a central and peripheral low-grade inflammation. In this sense, the microglial cells in the central nervous system are activated and release pro-inflammatory cytokines that up-regulate the inducible nitric oxide synthase (iNOS), promoting Nitric Oxide (NO) production. The excess of NO has been proposed to facilitate anxious states in humans and rodents. We evaluated whether consumption of a high-refined carbohydrate-containing diet (HC) in mice induced anxiety-like behavior in the Novelty Suppressed Feeding Test (NFST) trough facilitation of NO, in the prefrontal cortex (PFC) and hippocampus (HIP). We also verified if HC diet induces activation of microglial cells, alterations in cytokine and leptin levels in such regions. Male BALB/c mice received a standard diet or a HC diet for 3 days or 12 weeks. The chronic consumption of HC diet, but not acute, induced an anxiogenic-like effect in the NSF test and an increase in the nitrite levels in the PFC and HIP. The preferential iNOS inhibitor, aminoguanidine (50 mg/kg, i.p.), attenuated such effects. Moreover, microglial cells in the HIP and PFC were activated after chronic consumption of HC diet. Finally, the expression of iNOS in the PFC and TNF, IL6 and leptin levels in HIP were higher in chronically HC fed mice. Taken together, our data reinforce the notion that diets containing high-refined carbohydrate facilitate anxiety-like behavior, mainly after a long period of consumption. The mechanisms involve, at least in part, the augmentation of neuroinflammatory processes in brain areas responsible for anxiety control.

The DNA methylome in panic disorder: a case-control and longitudinal psychotherapy-epigenetic study

In panic disorder (PD), epigenetic mechanisms such as DNA methylation of candidate genes have been suggested to play a key role at the intersection of genetic and environmental factors. On an epigenome-wide level, however, only two studies in PD patients have been published so far, while to date no study has intra-individually analyzed dynamic epigenetic correlates of treatment-response in PD on a DNA methylome level. Here, an epigenome-wide association study (EWAS) was performed in a sample of 57 PD patients and matched healthy controls using the Illumina MethylationEPIC BeadChip, along with a longitudinal approach assessing changes on the DNA methylome level corresponding to clinical effects of a manualized six-week cognitive-behavioral therapy (CBT) in PD. While no epigenome-wide significant hits could be discerned, top suggestive evidence was observed for decreased methylation in PD at cg19917903 in the Cilia and Flagella Associated Protein 46 (CFAP46) gene, and for an increase in methylation after CBT at cg06943668 in the Interleukin 1 Receptor Type 1 (IL1R1) gene in treatment responders to CBT. Additional exploratory analyses based on biological validity and a combined statistical/biological ranking point to further new potential PD risk genes such as the CCL4L1 or GMNN genes, and suggest dynamic methylation of, e.g., the ZFP622 and the SLC43A2 genes along with response to CBT. These EWAS and first longitudinal epigenome-wide pilot data in PD add to the emerging candidate gene-based body of evidence for epigenetic mechanisms to be involved in PD pathogenesis and to possibly constitute dynamic biological correlates of therapeutic interventions.

Effects of SSRIs on peripheral inflammatory cytokines in patients with Generalized Anxiety Disorder

BACKGROUND

Extensive research into psychoneuroimmunology has led to substantial advances in our understanding of the reciprocal interactions between the central nervous system and the immune system in neuropsychiatric disorders. To date, inflammation has been implicated in the pathogenesis of depression and anxiety. The immunomodulating effects of antidepressants on depression have been reported, however, there is no evidence of the similar effects of antidepressants on anxiety. The aim of the study was to investigate the effects of selective serotonin reuptake inhibitors (SSRIs) on peripheral inflammatory cytokines in patients with first episode generalized anxiety disorder (GAD).

METHODS

A prospective cohort design was employed: 42 patients with first episode GAD were treated with either escitalopram or sertraline for 12 weeks. Anxiety was measured by the Generalized Anxiety Disorder Scale and the State Trait Anxiety Inventory, serum pro-inflammatory cytokine levels were measured by the enzyme-linked immunosorbent assay (ELISA), and CRP determined by an immunoturbidimetric method before and after SSRIs treatment RESULTS: Baseline levels of anxiety and pro-inflammatory cytokines including IL-1α, IL-6, IL-8, IL-12, IFN-γ, and CRP were significantly reduced after treatment of SSRIs (p < 0.05 in all cases). In addition, the change of anxiety measures co-vary with the change of peripheral cytokine levels (p < 0.05 in all cases). The regression model revealed that log transformed baseline levels of CRP and IL-6 predicted treatment response (p < 0.05 in both cases).

CONCLUSIONS

This study is the first to investigate the effects of SSRIs on pro-inflammatory cytokines in patients with first episode GAD. The findings indicate moderate acute anti-inflammatory effects of SSRIs in GAD, and suggest that these anti-inflammatory effects may underlie anxiolytic effects of SSRIs. The study also indicates that serum levels of CRP and IL-6 may predict treatment response. However, data from randomized controlled trials is warranted to confirm these findings.

The immune system and psychiatric disease: a basic science perspective

Mental illness exerts a major burden on human health, yet evidence-based treatments are rudimentary due to a limited understanding of the underlying pathologies. Clinical studies point to roles for the immune system in psychiatric diseases, while basic science has revealed that the brain has an active and multi-cellular resident immune system that interacts with peripheral immunity and impacts behavior. In this perspective, we highlight evidence of immune involvement in human psychiatric disease and review data from animal models that link immune signaling to neuronal function and behavior. We propose a conceptual framework for linking advances in basic neuroimmunology to their potential relevance for psychiatric diseases, based on the subtypes of immune responses defined in peripheral tissues. Our goal is to identify novel areas of focus for future basic and translational studies that may reveal the potential of the immune system for diagnosing and treating mental illnesses.

Short-term PM2.5 exposure and emergency hospital admissions for mental disease

Epidemiologic studies regarding the relationship between short-term exposure to particulate matter with a median aerodynamic diameter < 2.5 µm (PM_2.5) and mental disease are limited. This study examined the effects of short-term exposure to PM_2.5 on emergency admissions to the hospital for mental disease in Seoul, Korea. Data regarding 80,634 emergency admissions for mental diseases were collected from a nationally centralized healthcare claims database in Seoul during 2003-2013. Generalized linear models with climate variables were used to examine associations between short-term PM_2.5 exposure and mental disease admissions. To comprehensively assess PM_2.5 effects, we used single- and two-pollutant models, which considered other pollutants in combination with PM_2.5. The relative risk (RR) of emergency admissions for mental disease was 1.008 (95% confidence interval, 1.001-1.015) for each 10 μg/m³ increase in 2-day average PM_2.5 concentration. This effect persisted or became slightly stronger in the two-pollutant models that included carbon monoxide, nitrogen dioxide, ozone, or sulfur dioxide (RR, 1.01-1.021), but association appeared to be limited to individuals < 65 years of age. Significant association was estimated only during the warm season (RR, 1.021-1.023) in the two-pollutant models. The exposure-response curve was steeper at lower concentrations, suggesting that the risk of mental disease at lower concentrations of pm2.5 (0-30 µg/m³). PM_2.5 was associated with increased admissions even when it was below the World Health Organization's Air Quality Guidelines (25 μg/m³), but the association was not statistically significant. Thus, based on the data from a large database, exposure to PM_2.5 was associated with increases in emergency admissions for mental diseases, and this association was significant during the warm season. PM_2.5 may even affect mental disease at levels below the current air quality guidelines. These results provide substantial insight regarding the effects of air pollutants and have important implications for policy makers.

A comparison of hippocampal microglial responses in aged and young rodents following dependent and non-dependent binge drinking

Alcoholism is a highly visible and prevalent issue in the United States. Although binge-drinking is assumed to be a college-age problem, older adults (ages 65+) consume binge amounts of alcohol and have alcohol use disorders (AUDs). Moreover, individuals with alcohol dependence in their youth often continue to drink as they age. As such, this study tested the hypothesis that the effects of alcohol on hippocampal microglia are exacerbated in aged versus younger rodents in two AUD models. Briefly, adult (2-3 months) and aged (15+ months) Sprague-Dawley rats were administered alcohol or control diet using the Majchrowicz model to study alcohol-induced neurodegeneration. To study the effects of non-dependent binge consumption on microglia, adolescent (6-8 weeks) and aged (18+ months) C57/BL6N were subjected to the Drinking in the Dark paradigm. Microglia number and densitometry were assessed using immunohistochemistry. Hippocampal subregional and model/species-specific effects of alcohol were observed, but overall, aging did not appear to increase the alcohol-induced microglia reactivity as measured by Iba-1 densitometry. However, analysis of microglial counts revealed a significant decrease in the number microglia cells in both the alcohol-induced neurodegeneration and DID model across age groups. In the dentate gyrus, the loss of microglia was exacerbated by aging, particularly in mice after DID, non-dependent model. Using qRT-PCR, the persistence of alcohol and aging effects was assessed following the DID model. Allograft Inflammatory Factor 1 mRNA was increased in both young and aged mice by alcohol exposure; however, only in the aged mice did the alcohol effect persist. Overall, these data imply that the microglial response to alcohol is complex with evidence of depressed numbers of microglia but also increased reactivity with advanced age.

Altered temporal variance and functional connectivity of BOLD signal is associated with state anxiety during acute systemic inflammation

Systemic inflammation is accompanied by complex behavioral changes and disturbed emotion regulation that have been related to the pathophysiology of mood disorders including depression and anxiety. However, the causal role of systemic inflammation on mood disorders is still unclear. We herein investigated neural resting state patterns of temporal variance of the amygdala and functional connectivity within the salience network underlying changes in state anxiety during experimentally-induced systemic inflammation. In this randomized, double-blind study, N = 43 healthy men received an intravenous injection of either low-dose lipopolysaccharide (LPS, 0.4 ng/kg body weight) or saline. Resting state functional magnetic resonance imaging was assessed before and 3.5 h after injection. State anxiety, assessed with a standardized questionnaire, and plasma cytokine concentrations were repeatedly measured. LPS administration induced a transient systemic inflammatory response reflected in increases in plasma Interleukin (IL)-6 and Tumor Necrosis Factor (TNF)-α concentration. Compared to placebo, state anxiety and temporal variance in the amygdala significantly increased while functional connectivity in the salience network decreased during LPS-induced systemic inflammation. Together, these data indicate that acute systemic inflammation alters temporal variance of the BOLD signal as well as functional connectivity in brain regions and networks implicated in emotion processing and regulation. These results are of translational importance to encourage further research on the role of inflammatory pathways in the pathophysiology of neuropsychiatric conditions including anxiety disorders.

Anti-TNF-alpha antibody attenuates subarachnoid hemorrhage-induced apoptosis in the hypothalamus by inhibiting the activation of Erk

BACKGROUND

Subarachnoid hemorrhage (SAH) can induce apoptosis in many regions of the brain including the cortex and hippocampus. However, few studies have focused on apoptosis in the hypothalamus after SAH. Although some antiapoptotic strategies have been developed for SAH, such as anti-tumor necrosis factor-alpha (TNF-α) antibody, the molecular mechanisms underlying this condition have yet to be elucidated. Therefore, the purpose of this study was to evaluate whether SAH could induce apoptosis in the hypothalamus and identify the potential molecular mechanisms underlying the actions of anti-TNF-α antibody, as a therapeutic regimen, upon apoptosis.

MATERIALS AND METHODS

SAH was induced in a rat model. Thirty minutes prior to SAH, anti-TNF-α antibody or U0126, an extracellular signal-regulated kinase (Erk) inhibitor, was microinjected into the left lateral cerebral ventricle. In addition, phorbol-12-myristate-13-acetate was injected intraperitoneally immediately after the anti-TNF-α antibody microinjection. Then, real-time polymerase chain reaction, Western blotting and immunohistochemistry were used to detect the expression of caspase-3, bax, bcl-2, phosphorylated Erk (p-Erk) and Erk. Finally, anxiety-like behavior was identified by using open field.

RESULTS

Levels of caspase-3, bax and bcl-2, all showed a temporary rise after SAH in the hypothalamus, indicating the induction of apoptosis in this brain region. Interestingly, we found that the microinjection of anti-TNF-α antibody could selectively block the elevated levels of bax, suggesting the potential role of anti-TNF-α antibody in the inhibition of SAH-induced apoptosis in the hypothalamus. Moreover, we found that Erk activation was necessary for apoptosis after SAH and that the microinfusion of anti-TNF-α antibody could inhibit apoptosis by suppressing the increase of p-Erk in the hypothalamus. Finally, our data indicated that the infusion of anti-TNF-α antibody could improve anxiety-like behavior.

CONCLUSION

Collectively, our data demonstrate that anti-TNF-α antibody attenuates apoptosis in the hypothalamus by inhibiting the activation of Erk, which plays an important role in the treatment of SAH.

Peripheral proinflammatory cytokines in Chinese patients with generalised anxiety disorder

BACKGROUND

Inflammatory responses and inflammatory cytokines have been implicated in the pathogenesis of affective disorders, particularly major depression. Given the limited evidence relating to the potential role of proinflammatory cytokines in generalised anxiety disorder (GAD), we aimed to examine peripheral proinflammatory cytokines in Chinese patients with GAD.

METHODS

A case-controlled cross-sectional study design, with recruitment of 48 patients with first episode GAD and 48 matched healthy controls. All participants completed measures of anxiety using well-established questionnaires, and serum levels of pro-inflammatory cytokines were measured using multiplex technology.

RESULTS

Serum levels of CRP, IL-1α, IL-2, IL-6, IL-8, IL-12, IFN-γ, and GM-CSF were significantly higher in the GAD group in comparison to the control group (p < 0.05). Pearson correlation revealed significant positive correlations between anxiety measures and serum levels of CRP, IL-1α, IL-6, IL-8, IFN-γ, and GM-CSF (p < 0.05).

LIMITATIONS

The cross-sectional study design does not permit definite conclusions on causal directions between inflammation and GAD. The study was limited to a panel of 8 cytokines and does not exclude the possibility of other important cytokines being involved.

CONCLUSIONS

These findings indicate an elevated peripheral proinflammatory response, and provide further support for low grade inflammation in GAD. Further research may identify an 'inflammatory signature' for diagnosis and treatment response, and guide the search for novel pharmacological interventions.

Population attributable fractions for Type 2 diabetes: an examination of multiple risk factors including symptoms of depression and anxiety

BACKGROUND

Population attributable fractions (PAFs) are frequently used to quantify the proportion of Type 2 diabetes cases due to single risk factors, an approach which may result in an overestimation of their individual contributions. This study aimed to examine Type 2 diabetes incidence associated with multiple risk factor combinations, including the metabolic syndrome, behavioural factors, and specifically, depression and anxiety.

METHODS

Using data from the population-based HUNT cohort, we examined incident diabetes in 36,161 Norwegian adults from 1995 to 2008. PAFs were calculated using Miettinen's case-based formula, using relative risks estimated from multivariate regression models.

RESULTS

Overall, the studied risk factors accounted for 50.5% of new diabetes cases (78.2% in men and 47.0% in women). Individuals exposed to both behavioural and metabolic factors were at highest risk of diabetes onset (PAF = 22.9%). Baseline anxiety and depression contributed a further 13.6% of new cases to this combination. Men appeared to be particularly vulnerable to the interaction between metabolic, behavioural and psychological risk factors.

CONCLUSION

This study highlights the importance of risk factor clustering in diabetes onset, and is the first that we know of to quantify the excess fraction of incident diabetes associated with psychological risk factor interactions.

Effects of Shambhavi Mahamudra Kriya, a Multicomponent Breath-Based Yogic Practice ( Pranayama), on Perceived Stress and General Well-Being

Stress-induced disorders such as anxiety represent the leading causes of adult disability worldwide. Previous studies indicate that yoga and other contemplative practices such as pranayama, or controlled yogic breathing techniques, may be effective in the treatment of mood disorders and stress. In this study, 142 individuals (mean age = 43 years; SD = 13.90) participated in a 3-day retreat program during which they learned Shambhavi Mahamudra kriya, which is a yogic practice that includes both deep breathing and meditation techniques. Participants were instructed to practice the kriya each day for 21 minutes. After 6 weeks of daily practice, participants reported subjectively lower levels of perceived stress (Perceived Stress Scale) and higher levels of general well-being (General Well-Being Scale) compared to baseline. These results support the notion that Shambhavi Mahamudra kriya may represent a natural treatment for stress reduction.

Anxiety and Atopic Disease: Comorbidity in a Youth Mental Health Setting

Anxiety frequently co-occurs with atopic diseases (e.g., allergies) in community samples, although data are limited to community and pediatric medical samples. Little work has examined atopy rates among mental health treatment seeking youth or whether youth with comorbid anxiety and atopy present similarly to non-comorbid youth. Using initial intake data from a University-based specialty youth clinic for anxiety and depressive disorders (n = 189), rates of atopic comorbidity were benchmarked against lifetime prevalence estimates in epidemiological samples. Anxiety severity and parental stress were compared between youth with and without atopy. Results indicated high rates of atopy in the clinical sample (51.3 %) relative to population atopy estimates (34.5 %). Anxious youth with atopy exhibited more overall and generalized anxiety symptoms relative to non-atopic youth (ps < .05); parental stress was comparable between atopic and non-atopic anxious youth. This suggests potentially heightened clinical severity for youth with co-occurring anxiety and atopy.

The pro-inflammatory cytokines, salivary cortisol and alpha-amylase are associated with generalized anxiety disorder (GAD) in patients with asthma

Generalized anxiety disorder (GAD) is common in patients with asthma. High levels of GAD may lead both to exacerbation of the condition and poor management. However, the physiological mechanisms of GAD in asthma patient is unclear. This study investigated the associations between the diurnal rhythm of sputum cytokines, salivary cortisol, α-amylase and GAD in asthma patients. Patients with co-morbid GAD and asthma showed higher sputum IL-1 AUC, sputum IL-6 AUC and sAA AUC. And there were positive correlations between Hamilton anxiety scale (HAMA) scores and sputum IL-1 AUC concentrations (r=0.37, P=0.002), HAMA scores and sputum IL-6 AUC (r=0.56, P<0.001), HAMA scores and sAA AUC (r=0.75, P<0.001). Also, there were positive correlations between Sputum IL-1 AUC and sAA AUC (r=0.40, P<0.001), between Sputum IL-6 AUC and sAA AUC. Stepwise multiple regression analyses showed the combination of sputum sAA AUC, IL-1 AUC, IL-6 AUC and cortisol AUC was the best predictor of HAMA scores (ΔR²=0.439, F(4,63)=14.086, p<0.001). Therefore, pro-inflammatory cytokines, salivary cortisol and alpha-amylase may all be involved in the occurrence of GAD in asthma patients.

Effects of caffeine on behavioral and inflammatory changes elicited by copper in zebrafish larvae: Role of adenosine receptors

This study investigated the effects of caffeine in the behavioral and inflammatory alterations caused by copper in zebrafish larvae, attempting to correlate these changes with the modulation of adenosine receptors. To perform a survival curve, 7dpf larvae were exposed to 10μM CuSO₄, combined to different concentrations of caffeine (100μM, 500μM and 1mM) for up to 24h. The treatment with copper showed lower survival rates only when combined with 500μM and 1mM of caffeine. We selected 4 and 24h as treatment time-points. The behavior evaluation was done by analyzing the traveled distance, the number of entries in the center, and the length of permanence in the center and the periphery of the well. The exposure to 10μM CuSO₄ plus 500μM caffeine at 4 and 24h changed the behavioral parameters. To study the inflammatory effects of caffeine, we assessed the PGE₂ levels by using UHPLC-MS/MS, and TNF, COX-2, IL-6 and IL-10 gene expression by RT-qPCR. The expression of adenosine receptors was also evaluated with RT-qPCR. When combined to copper, caffeine altered inflammatory markers depending on the time of exposure. Adenosine receptors expression was significantly increased, especially after 4h exposure to copper and caffeine together or separately. Our results demonstrated that caffeine enhances the inflammation induced by copper by decreasing animal survival, altering inflammatory markers and promoting behavioral changes in zebrafish larvae. We also conclude that alterations in adenosine receptors are related to those effects.

Pharmacotherapy in Generalized Anxiety Disorder: Novel Experimental Medicine Models and Emerging Drug Targets

Many pharmacological and psychological approaches have been found efficacious in patients with generalized anxiety disorder (GAD), but many treatment-seeking patients will not respond and others will relapse despite continuing with interventions that initially had beneficial effects. Other patients will respond but then stop treatment early because of untoward effects such as sexual dysfunction, drowsiness, and weight gain. There is much scope for the development of novel approaches that could have greater overall effectiveness or acceptability than currently available interventions or that have particular effectiveness in specific clinical subgroups. 'Experimental medicine' studies in healthy volunteers model disease states and represent a proof-of-concept approach for the development of novel therapeutic interventions: they determine whether to proceed to pivotal efficacy studies and so can reduce delays in translating innovations into clinical practice. Investigations in healthy volunteers challenged with the inhalation of air 'enriched' with 7.5% carbon dioxide (CO₂) indicate this technique provides a validated and robust experimental medicine model, mirroring the subjective, autonomic, and cognitive features of GAD. The anxiety response during CO₂ challenge probably involves both central noradrenergic neurotransmission and effects on acid-base sensitive receptors and so may stimulate development of novel agents targeted at central chemosensors. Increasing awareness of the potential role of altered cytokine balance in anxiety and the interplay of cytokines with monoaminergic mechanisms may also encourage the investigation of novel agents with modulating effects on immunological profiles. Although seemingly disparate, these two approaches to treatment development may pivot on a shared mechanism in exerting anxiolytic-like effects through pharmacological effects on acid-sensing ion channels.

Xiaoyaosan exerts anxiolytic-like effects by down-regulating the TNF-α/JAK2-STAT3 pathway in the rat hippocampus

Although the anxiolytic-like effects of Xiaoyaosan, a Chinese herbal formula, have been described in many previous studies, its underlying mechanism remains undefined. The cytokine tumour necrosis factor-α (TNF-α) and its closely associated janus kinase 2 (JAK2)-signal transducer and activator of transcription (STAT3) signalling pathway regulate the neuro-inflammatory response in the brain, thus participating in the development of anxiety. Our purpose was to investigate whether the anxiolytic-like effects of Xiaoyaosan are related to the TNF-α/JAK2-STAT3 pathway in the hippocampus. We examined the effects of Xiaoyaosan on behaviours exhibited in the elevated plus maze test, open field test and novelty-suppressed feeding test as well as hippocampal neuron damage and changes in the TNF-α/JAK2-STAT3 pathway in a rat model of chronic immobilization stress (CIS)-induced anxiety. Xiaoyaosan exerts anxiolytic-like effects on CIS-induced anxiety, with a significant alleviation of anxiety-like behaviours, an attenuation of hippocampal neuron damage, and a reversal of the activation of the TNF-α/JAK2-STAT3 pathway in the hippocampus that are similar to the effects of the JAK2 antagonist AG490. However, Xiaoyaosan and AG490 failed to effectively regulate apoptosis-related factors, including Bax and Caspase-3. These results suggest that Xiaoyaosan attenuates stress-induced anxiety behaviours by down-regulating the TNF-α/JAK2-STAT3 pathway in the rat hippocampus.

Chronology of Onset of Mental Disorders and Physical Diseases in Mental-Physical Comorbidity - A National Representative Survey of Adolescents

Background

The objective was to estimate temporal associations between mental disorders and physical diseases in adolescents with mental-physical comorbidities.

Methods

This article bases upon weighted data (N = 6483) from the National Comorbidity Survey Adolescent Supplement (participant age: 13–18 years), a nationally representative United States cohort. Onset of Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition lifetime mental disorders was assessed with the fully structured World Health Organization Composite International Diagnostic Interview, complemented by parent report. Onset of lifetime medical conditions and doctor-diagnosed diseases was assessed by self-report.

Results

The most substantial temporal associations with onset of mental disorders preceding onset of physical diseases included those between affective disorders and arthritis (hazard ratio (HR) = 3.36, 95%-confidence interval (CI) = 1.95 to 5.77) and diseases of the digestive system (HR = 3.39, CI = 2.30 to 5.00), between anxiety disorders and skin diseases (HR = 1.53, CI = 1.21 to 1.94), and between substance use disorders and seasonal allergies (HR = 0.33, CI = 0.17 to 0.63). The most substantial temporal associations with physical diseases preceding mental disorders included those between heart diseases and anxiety disorders (HR = 1.89, CI = 1.41 to 2.52), epilepsy and eating disorders (HR = 6.27, CI = 1.58 to 24.96), and heart diseases and any mental disorder (HR = 1.39, CI = 1.11 to 1.74).

Conclusions

Findings suggest that mental disorders are antecedent risk factors of certain physical diseases in early life, but also vice versa. Our results expand the relevance of mental disorders beyond mental to physical health care, and vice versa, supporting the concept of a more integrated mental-physical health care approach, and open new starting points for early disease prevention and better treatments, with relevance for various medical disciplines.

Mood disturbance during experimental endotoxemia: Predictors of state anxiety as a psychological component of sickness behavior

Lipopolysaccharide (LPS) administration is a well-established model to assess afferent immune-to-brain communication and behavioral aspects of inflammation. Nevertheless, only few studies in comparatively small samples have assessed state anxiety as a psychological component of sickness behavior despite possible clinical implications for the pathophysiology of neuropsychiatric conditions. Thus, the goal of the present analyses carried out in a large, pooled dataset from two independent study sites was to analyze the state anxiety response to LPS administration and to investigate predictors (i.e., cytokine changes; pre-existing anxiety and depression symptoms assessed with the Hospital Anxiety and Depression Scale) of the LPS-induced state anxiety changes at different time points after LPS administration. Data from 186 healthy volunteers who participated in one of six randomized, placebo-controlled human studies involving intravenous administration of LPS at doses of 0.4-0.8ng/kg body weight were combined. State anxiety as well as circulating interleukin (IL)-6, tumor necrosis factor (TNF)-α and IL-10 concentrations were significantly increased 2h and 3h after LPS administration, with a peak at 2h, and returned to baseline 6h after administration. Greater changes in IL-6 from baseline to 3h after LPS administration significantly and independently predicted a more pronounced LPS-induced state anxiety response. In addition, higher pre-existing subclinical anxiety symptoms significantly predicted a lower increase in state anxiety 3h and 6h after LPS-administration, which was mediated by TNF-α changes. In conclusion, our findings give additional support for a putative role of inflammatory mechanisms in the pathophysiology of stress-related and anxiety disorders and give new insight on the potential role of pre-existing subclinical affective symptoms.

Prevention of unpredictable chronic stress-related phenomena in zebrafish exposed to bromazepam, fluoxetine and nortriptyline

RATIONALE

Several model organisms have been employed to study the impacts of stress on biological systems. Different models of unpredictable chronic stress (UCS) have been established in rodents; however, these protocols are expensive, long-lasting, and require a large physical structure. Our group has recently reported an UCS protocol in zebrafish with several advantages compared to rodent models. We observed that UCS induced behavioral, biochemical, and molecular changes similar to those observed in depressed patients, supporting the translational relevance of the protocol.

OBJECTIVES

Considering that a pharmacological assessment is lacking in this zebrafish model, our aim was to evaluate the effects of anxiolytic (bromazepam) and antidepressant drugs (fluoxetine and nortriptyline) on behavioral (novel tank test), biochemical (whole-body cortisol), and molecular parameters (cox-2, tnf-α, il-6, and il-10 gene expression) in zebrafish subjected to UCS.

RESULTS

We replicated previous data showing that UCS induces behavioral and neuroendocrine alterations in zebrafish, and we show for the first time that anxiolytic and antidepressant drugs are able to prevent such effects. Furthermore, we extended the molecular characterization of the model, revealing that UCS increases expression of the pro-inflammatory markers cox-2 and il-6, which was also prevented by the drugs tested.

CONCLUSIONS

This study reinforces the use of zebrafish as a model organism to study the behavioral and physiological effects of stress. The UCS protocol may also serve as a screening tool for evaluating new drugs that can be used to treat psychiatric disorders with stress-related etiologies.

The Immune System and the Role of Inflammation in Perinatal Depression

Major depression during pregnancy is a common psychiatric disorder that arises from a complex and multifactorial etiology. Psychosocial stress, sex, hormones, and genetic vulnerability increase the risk for triggering mood disorders. Microglia and toll-like receptor 4 play a crucial role in triggering wide and varied stress-induced responses mediated through activation of the inflammasome; this leads to the secretion of inflammatory cytokines, increased serotonin metabolism, and reduction of neurotransmitter availability along with hypothalamic-pituitary-adrenal axis hyperactivity. Dysregulation of this intricate neuroimmune communication network during pregnancy modifies the maternal milieu, enhancing the emergence of depressive symptoms and negative obstetric and neuropsychiatric outcomes. Although several studies have clearly demonstrated the role of the innate immune system in major depression, it is still unclear how the placenta, the brain, and the monoaminergic and neuroendocrine systems interact during perinatal depression. Thus, in the present review we describe the cellular and molecular interactions between these systems in major depression during pregnancy, proposing that the same stress-related mechanisms involved in the activation of the NLRP3 inflammasome in microglia and peripheral myeloid cells in depressed patients operate in a similar fashion in the neuroimmune placenta during perinatal depression. Thus, activation of Toll-like receptor 2 and 4 signaling and the NLRP3 inflammasome in placental immune cells may promote a shift of the Th1/Th2 bias towards a predominant Th1/Th17 inflammatory response, associated with increased secretion of pro-inflammatory cytokines, among other secreted autocrine and paracrine mediators, which play a crucial role in triggering and/or exacerbating depressive symptoms during pregnancy.

Angiotensin type 1a receptors in the paraventricular nucleus of the hypothalamus control cardiovascular reactivity and anxiety-like behavior in male mice

This study tested the hypothesis that deletion of angiotensin type 1a receptors (AT1a) from the paraventricular nucleus of hypothalamus (PVN) attenuates anxiety-like behavior, hypothalamic-pituitary-adrenal (HPA) axis activity, and cardiovascular reactivity. We used the Cre/LoxP system to generate male mice with AT1a specifically deleted from the PVN. Deletion of the AT1a from the PVN reduced anxiety-like behavior as indicated by increased time spent in the open arms of the elevated plus maze. In contrast, PVN AT1a deletion had no effect on HPA axis activation subsequent to an acute restraint challenge but did reduce hypothalamic mRNA expression for corticotropin-releasing hormone (CRH). To determine whether PVN AT1a deletion inhibits cardiovascular reactivity, we measured systolic blood pressure, heart rate, and heart rate variability (HRV) using telemetry and found that PVN AT1a deletion attenuated restraint-induced elevations in systolic blood pressure and elicited changes in HRV indicative of reduced sympathetic nervous activity. Consistent with the decreased HRV, PVN AT1a deletion also decreased adrenal weight, suggestive of decreased adrenal sympathetic outflow. Interestingly, the altered stress responsivity of mice with AT1a deleted from the PVN was associated with decreased hypothalamic microglia and proinflammatory cytokine expression. Collectively, these results suggest that deletion of AT1a from the PVN attenuates anxiety, CRH gene transcription, and cardiovascular reactivity and reduced brain inflammation may contribute to these effects.

Association between neighbourhood air pollution concentrations and dispensed medication for psychiatric disorders in a large longitudinal cohort of Swedish children and adolescents

OBJECTIVE

To investigate associations between exposure to air pollution and child and adolescent mental health.

DESIGN

Observational study.

SETTING

Swedish National Register data on dispensed medications for a broad range of psychiatric disorders, including sedative medications, sleeping pills and antipsychotic medications, together with socioeconomic and demographic data and a national land use regression model for air pollution concentrations for NO2, PM10 and PM2.5.

PARTICIPANTS

The entire population under 18 years of age in 4 major counties. We excluded cohort members whose parents had dispensed a medication in the same medication group since the start date of the register. The cohort size was 552 221.

MAIN OUTCOME MEASURES

Cox proportional hazards models to estimate HRs and their 95% CIs for the outcomes, adjusted for individual-level and group-level characteristics.

RESULTS

The average length of follow-up was 3.5 years, with an average number of events per 1000 cohort members of ∼21. The mean annual level of NO2 was 9.8 µg/m(3). Children and adolescents living in areas with higher air pollution concentrations were more likely to have a dispensed medication for a psychiatric disorder during follow-up (HR=1.09, 95% CI 1.06 to 1.12, associated with a 10 µg/m(3) increase in NO2). The association with NO2 was clearly present in 3 out of 4 counties in the study area; however, no statistically significant heterogeneity was detected.

CONCLUSION

There may be a link between exposure to air pollution and dispensed medications for certain psychiatric disorders in children and adolescents even at the relatively low levels of air pollution in the study regions. The findings should be corroborated by others.

Effectiveness of disease-specific cognitive-behavioural therapy on depression, anxiety, quality of life and the clinical course of disease in adolescents with inflammatory bowel disease: study protocol of a multicentre randomised controlled trial (HAPPY-IBD)

Introduction

Adolescents with inflammatory bowel disease (IBD) show a higher prevalence of depression and anxiety, compared to youth with other chronic diseases. The inflammation-depression hypothesis might explain this association, and implies that treating depression can decrease intestinal inflammation and improve disease course. The present multicentre randomised controlled trial aims to test the effectiveness of an IBD-specific cognitive–behavioural therapy (CBT) protocol in reducing symptoms of subclinical depression and anxiety, while improving quality of life and disease course in adolescents with IBD.

Methods and analysis

Adolescents with IBD (10–20 years) from 7 hospitals undergo screening (online questionnaires) for symptoms of depression and anxiety. Those with elevated scores of depression (Child Depression Inventory (CDI) ≥13 or Beck Depression Inventory (BDI) II ≥14) and/or anxiety (Screen for Child Anxiety Related Disorders: boys ≥26, girls ≥30) receive a psychiatric interview. Patients meeting criteria for depressive/anxiety disorders are referred for psychotherapy outside the trial. Patients with elevated (subclinical) symptoms are randomly assigned to medical care-as-usual (CAU; n=50) or CAU plus IBD-specific CBT (n=50). Main outcomes: (1) reduction in depressive and/or anxiety symptoms after 3 months and (2) sustained remission for 12 months. Secondary outcomes: quality of life, psychosocial functioning, treatment adherence. In addition, we will assess inflammatory cytokines in peripheral blood mononuclear cells and whole blood RNA expression profiles. For analysis, multilevel linear models and generalised estimating equations will be used.

Ethics and dissemination

The Medical Ethics Committee of the Erasmus MC approved this study. If we prove that this CBT improves emotional well-being as well as disease course, implementation is recommended.

Trial registration number

NCT02265588.

Association of peripheral inflammation with body mass index and depressive relapse in bipolar disorder

Bipolar I disorder (BD) is associated with increased inflammation, which is believed to be central to disease etiology and progression. However, BD patients also have high rates of obesity, itself an inflammatory condition, and the relative contributions of mood illness and obesity to inflammation are unknown. Moreover, the impact of inflammation on clinical illness course has not been well studied. The objectives of this analysis were therefore: (1) to determine if inflammation in BD is mood illness-related or secondary to elevated body mass index (BMI), and (2) to investigate the impact of inflammation on prospectively-ascertained relapse into depression and mania. We measured the serum levels of 7 inflammatory cytokines (TNF-α, γ-interferon, monocyte chemoattractant protein-1 [MCP-1], IL-1α, IL-2, IL-6, and IL-8) and 2 anti-inflammatory cytokines (IL-4 and IL-10) in 52 early-stage BD patients and 22 healthy subjects. In patients, a multivariate multiple regression model that controlled for psychotropic medications found that higher BMI, but not recent (past-6-month) mood episodes, predicted greater inflammatory cytokines (p=.05). Healthy subjects also had a BMI-related increase in inflammatory cytokines (p<.01), but it was counter-balanced by a compensatory increase in anti-inflammatory cytokines (p=.02), reducing their total inflammatory burden from higher BMI. In patients, linear regression showed that two inflammatory cytokines predicted depressive relapse in the 12 months after cytokine measurement: IL-1α (p<.01) and MCP-1 (p<.01). These results suggest that elevated BMI is a significant contributor to inflammation in BD, more so even than recent mood illness severity. They also point to inflammation as an important predictor of illness course, particularly depressive relapse.

Cytokine Patterns in Healthy Adolescent Girls: Heterogeneity Captured by Variable and Person-Centered Statistical Strategies

BACKGROUND

Little is known about variation in individual cytokines/cytokine profiles for a large healthy, pediatric population. When cytokines in a healthy group are not abnormally high as in a disease state, it is challenging to determine appropriate statistical strategies. The aims of the study were (1) to describe variation among cytokine concentrations and profiles in healthy adolescent girls, (2) to illustrate utility of data reduction approaches novel to cytokine research, (variable-centered [principal factor analysis, PFA], person-centered [latent profile analysis, LPA]), and (3) to demonstrate utility of such methods in linking cytokine profiles to health outcomes (e.g., depressive, anxiety symptoms).

METHOD

Serum was analyzed for 13 cytokines representing adaptive and innate immune responses in 262 girls (age = 11, 13, 15, and 17 years).

RESULTS

There was great variation in cytokine concentrations. PFA revealed a four-factor solution explaining 73.13% of the shared variance among 13 cytokines (e.g., factor 1 included interleukin [IL]-4, IL-13, IL-5, interferon gamma; 26.65% of the shared variance). The LPA supported classifying girls into subgroups characterized by "high overall" (7.3% of sample), "high adaptive" (26.7%), "high innate" (21%), or "low overall" (45%) cytokine levels. Factors and profiles were useful in describing individual differences in depressive/anxiety symptoms (e.g., factor 1 positively associated with depressive symptoms but negatively with trait anxiety; increased depressive symptoms or trait anxiety was associated with greater likelihood of being in the "high adaptive" group).

CONCLUSIONS

Healthy girls showed differences in cytokine levels and patterns of variation and important associations with psychological variables. PFA and LPA offer novel approaches useful for examining cytokine panels in healthy populations.