Psychological variables as predictors of rubella antibody titers and fatigue--a prospective, double blind study

The effect of stress on the antibody response after vaccination in children aged 0-18 years: A systematic review

Stress has been associated with less effective vaccine responses in adults. This review aims to investigate the evidence for a similar association in children. A systematic review search was conducted in January 2021 in three databases: Medline, Embase and PsycInfo. An updated search of the Medline database was systematically conducted until the most recent update on September 25th, 2023, to ensure the inclusion of the most current research available. Keywords related to stress, vaccines and children were used, and a total of 7263 (+1528) studies were screened by two independent investigators. Six studies met the inclusion criteria for data extraction and analysis. For quality assessment of the studies, the risk of bias in non-randomized studies-of interventions (ROBINS-I) tool was applied. Most of the studies suggest a negative role of stress on vaccine responses. However, the scarcity of studies, lack of confirmatory studies, risk of bias and heterogeneity according to age, type of vaccine, measures of stress and vaccine responses prevent a clear conclusion. Future studies should emphasize the use of as strict study designs as possible, including well-defined stress metrics and thorough examination of both pre- and post-vaccination responses. Systematic review registration: Prospero CRD42021230490.

Personality, Preoperative Anxiety, and Postoperative Outcomes: A Review

Research has shown that personality is associated with anxiety levels in the general population. However, little is known about the relationship between personality and preoperative anxiety and the subsequent health outcomes in patients undergoing surgery. Therefore, this review aimed to identify studies that explored the relationship between personality traits and preoperative anxiety, as well as their association with postoperative outcomes. Existing literature shows that anxiety may play an intermediary role in the relationship between personality and postoperative outcomes. Severe anxiety may partially explain the adverse effects of certain personality traits, such as neuroticism, on postoperative outcomes. However, the relationship between personality traits, preoperative anxiety, and postoperative outcomes remains unclear. Interventions such as clinical evaluation, preoperative counseling, and management strategies can be of great value in identifying and resolving patients' anxiety and negative emotions to improve postoperative outcomes.

The Prevalence of Psychotic Symptoms, Violent Ideation, and Disruptive Behavior in a Population With SARS-CoV-2 Infection: Preliminary Study

Background

The COVID-19 disease results from infection by the SARS-CoV-2 virus to produce a range of mild to severe physical, neurological, and mental health symptoms. The COVID-19 pandemic has indirectly caused significant emotional distress, triggering the emergence of mental health symptoms in individuals who were not previously affected or exacerbating symptoms in those with existing mental health conditions. Emotional distress and certain mental health conditions can lead to violent ideation and disruptive behavior, including aggression, threatening acts, deliberate harm toward other people or animals, and inattention to or noncompliance with education or workplace rules. Of the many mental health conditions that can be associated with violent ideation and disruptive behavior, psychosis can evidence greater vulnerability to unpredictable changes and being at a greater risk for them. Individuals with psychosis can also be more susceptible to contracting COVID-19 disease.

Objective

This study aimed to investigate whether violent ideation, disruptive behavior, or psychotic symptoms were more prevalent in a population with COVID-19 and did not precede the pandemic.

Methods

In this preliminary study, we analyzed questionnaire responses from a population sample (N=366), received between the end of February 2021 and the start of March 2021 (1 year into the COVID-19 pandemic), regarding COVID-19 illness, violent ideation, disruptive behavior, and psychotic symptoms. Using the Wilcoxon rank sum test followed by multiple comparisons correction, we compared the self-reported frequency of these variables for 3 time windows related to the past 1 month, past 1 month to 1 year, and >1 year ago among the distributions of people who answered whether they tested positive or were diagnosed with COVID-19 by a clinician. We also used multivariable logistic regression with iterative resampling to investigate the relationship between these variables occurring >1 year ago (ie, before the pandemic) and the likelihood of contracting COVID-19.

Results

We observed a significantly higher frequency of self-reported violent ideation, disruptive behavior, and psychotic symptoms, for all 3 time windows of people who tested positive or were diagnosed with COVID-19 by a clinician. Using multivariable logistic regression, we observed 72% to 94% model accuracy for an increased incidence of COVID-19 in participants who reported violent ideation, disruptive behavior, or psychotic symptoms >1 year ago.

Conclusions

This preliminary study found that people who reported a test or clinician diagnosis of COVID-19 also reported higher frequencies of violent ideation, disruptive behavior, or psychotic symptoms across multiple time windows, indicating that they were not likely to be the result of COVID-19. In parallel, participants who reported these behaviors >1 year ago (ie, before the pandemic) were more likely to be diagnosed with COVID-19, suggesting that violent ideation, disruptive behavior, in addition to psychotic symptoms, were associated with COVID-19 with an approximately 70% to 90% likelihood.

Immune response to vaccination in adults with mental disorders: A systematic review

BACKGROUND

Mental disorders are associated with immune dysregulation as measured by serum levels of biological markers of immunity. Adults with mental disorders have also been reported to have attenuated post vaccine immune response. The COVID-19 pandemic has invited the need to determine whether individuals with mental disorders exhibit differential immune response following the administration of vaccines for other infections.

METHODS

A systematic search of MEDLINE, Embase, Cochrane, and PsycInfo was conducted from inception to May 2021 investigating vaccine response in persons with mental disorders, as measured by biological markers of immunity (i.e., antibodies, cytokines).

RESULTS

Thirteen articles were identified which evaluated vaccine efficacy in persons with mental disorders. Individuals with major depressive disorder (MDD) or schizophrenia revealed attenuated immune response to vaccination, or no statistical difference compared to control subjects. Individuals with anorexia nervosa or post-traumatic stress disorder (PTSD) displayed no attenuated post-vaccination antibody level. Individuals with insomnia displayed lower levels of antibodies after vaccination, whereas individuals with obstructive sleep apnea (OSA) displayed no difference in vaccine response compared to control subjects.

LIMITATIONS

The limitations of this review include the relatively few articles included (n = 13) and small sample sizes (less than thirty subjects) in the majority of articles.

CONCLUSION

Vaccine response in adults with a mental disorder remains inconclusive. Notwithstanding the heterogeneity and relatively small number of studies, available evidence does suggest attenuated immune response across disparate vaccinations. Future research is required to confirm vaccine efficacy in persons with mental disorders, especially regarding immune responses to COVID-19 vaccination.

Emotional Distress, Targeted Rejection, and Antibody Production After Influenza Vaccination in Adolescence

OBJECTIVE

The purpose of this study was to explore how both ongoing emotional distress and the experience of a targeted rejection over the past 6 months are associated with adolescents' antibody response to influenza virus vaccination. We predicted that experiencing a targeted rejection would amplify the hypothesized negative association between emotional distress and antibody response after vaccination.

METHODS

Adolescent participants (N = 148) completed two study visits (mean [standard deviation] days between visits = 27.4 [1.8]). At the first visit, they provided blood samples, were administered the seasonal (2018-2019) quadrivalent influenza vaccine (Fluzone, Sanofi Pasteur), completed questionnaires, and participated in a semistructured interview. At the second visit, they provided another blood sample. Hemagglutination-inhibition assays were conducted to determine prevaccination and postvaccination antibody titers. Targeted rejection experiences were coded from adolescents' interviews.

RESULTS

The emotional distress by targeted rejection interaction predicted antibody response to the two A strains and the composite of all vaccine strains (b values = -0.451 to -0.843, p values < .05), but not the two B strains. Results suggested that, among adolescents who experienced a targeted rejection over the past 6 months, emotional distress was negatively associated with vaccine response (however, this finding did not reach statistical significance). Conversely, among adolescents who did not experience a targeted rejection, emotional distress was positively associated with vaccine response (b = 0.173, p = .032).

CONCLUSIONS

The current study highlights the importance of evaluating both acute life events and ongoing distress as they relate to adaptive immune functioning in adolescence.

Psychological and Behavioral Predictors of Vaccine Efficacy: Considerations for COVID-19

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine candidates are being evaluated, with the goal of conferring immunity on the highest percentage of people who receive the vaccine as possible. It is noteworthy that vaccine efficacy depends not only on the vaccine but also on characteristics of the vaccinated. Over the past 30 years, a series of studies has documented the impact of psychological factors on the immune system's vaccine response. Robust evidence has demonstrated that stress, depression, loneliness, and poor health behaviors can impair the immune system's response to vaccines, and this effect may be greatest in vulnerable groups such as the elderly. Psychological factors are also implicated in the prevalence and severity of vaccine-related side effects. These findings have generalized across many vaccine types and therefore may be relevant to the SARS-CoV-2 vaccine. In this review, we discuss these psychological and behavioral risk factors for poor vaccine responses, their relevance to the COVID-19 pandemic, as well as targeted psychological and behavioral interventions to boost vaccine efficacy and reduce side effects. Recent data suggest these psychological and behavioral risk factors are highly prevalent during the COVID-19 pandemic, but intervention research suggests that psychological and behavioral interventions can increase vaccine efficacy.

Personality variable differences between disease clusters

Previous studies of personality and health have focused mainly on the influence of psychological factors on single diseases such as cancer and coronary heart disease (CHD), thereby neglecting the problem of comorbidity (i.e. the combination of different diseases). The main focus of the present study was the discrimination between single‐ and multiple‐disease conditions on the basis of personality traits. An extensive battery of personality scales implicated in health was administered to a sample of n=5133 individuals of both genders between the ages of 40 and 65. Subjects also reported their health or illness status. A factor analysis of the personality scales yielded five dimensions clearly interpretable as “Emotional Lability”, “Type A Behaviour”, “Behavioural Control”, “Locus of Control over Diseases”, and “Psychoticism”. Hierarchical cluster analyses of the subsample of participants who reported suffering from more than one disease led to eight clusters representing individuals with different combinations of diseases. Generally, there were very few significant differences between healthy and single‐disease participants with regard to personality. However, mean factor scores calculated for “Emotional Lability” were higher across the multiple‐disease groups than in the healthy and single‐disease groups. No other personality factor showed this trend. In general the results reported here show the important role negative affectivity (e.g. Emotional Lability, Neuroticism, Depression) plays in differentiating between single and multiple diseases. Copyright © 2003 John Wiley & Sons, Ltd.

Posttraumatic Stress Disorder and Incident Infections: A Nationwide Cohort Study

BACKGROUND

It is unknown whether posttraumatic stress disorder (PTSD) is associated with incident infections. This study's objectives were to examine (1) the association between PTSD diagnosis and 28 types of infections and (2) the interaction between PTSD diagnosis and sex on the rate of infections.

METHODS

The study population consisted of a longitudinal nationwide cohort of all residents of Denmark who received a PTSD diagnosis between 1995 and 2011, and an age- and sex-matched general population comparison cohort. We fit Cox proportional hazards regression models to examine associations between PTSD diagnosis and infections. To account for multiple estimation, we adjusted the hazard ratios (HRs) using semi-Bayes shrinkage. We calculated interaction contrasts to assess the presence of interaction between PTSD diagnosis and sex.

RESULTS

After semi-Bayes shrinkage, the HR for any type of infection was 1.8 (95% confidence interval: 1.6, 2.0), adjusting for marital status, non-psychiatric comorbidity, and diagnoses of substance abuse, substance dependence, and depression. The association between PTSD diagnosis and some infections (e.g., urinary tract infections) were stronger among women, whereas other associations were stronger among men (e.g., skin infections).

CONCLUSIONS

This study's findings suggest that PTSD diagnosis is a risk factor for numerous infection types and that the associations between PTSD diagnosis and infections are modified by sex.

Stress-elicited glucocorticoid receptor signaling upregulates TIGIT in innate-like invariant T lymphocytes

Stress is known to impede certain host defense mechanisms, including those governed by conventional T lymphocytes. However, whether innate-like T lymphocytes, such as invariant natural killer T (iNKT) and mucosa-associated invariant T (MAIT) cells, are impacted by stress is unclear. Herein, we report that prolonged psychological stress caused by physical confinement results in robust upregulation of T cell immunoreceptor with immunoglobulin and ITIM domains (TIGIT), an immune checkpoint receptor that controls antitumor and antiviral immune responses. Elevated TIGIT expression was found not only on NK and conventional T cells, but also on iNKT and MAIT cells. Stress-provoked TIGIT upregulation was reversed through treatment with the glucocorticoid receptor (GR) antagonist RU486, but not with 6-hydroxydopamine that induces chemical sympathectomy. A Cre/Lox gene targeting model in which GR was ablated in cells expressing Lck under its proximal promoter revealed that TIGIT upregulation in stressed animals stems from direct GR signaling in T and iNKT cells. In fact, long-term oral administration of exogenous corticosterone (CS) to wild-type C57BL/6 (B6) mice was sufficient to increase TIGIT expression levels on T and iNKT cells. In vitro treatment with CS also potently and selectively upregulated TIGIT, but not CTLA-4 or LAG-3, on mouse iNKT and MAIT hybridomas. These results were recapitulated using primary hepatic iNKT and MAIT cells from wild-type B6 and B6.MAIT^CAST mice, respectively. Subjecting B6.MAIT^CAST mice to physical restraint also raised the frequency of TIGIT⁺ cells among hepatic MAIT cells in a GR-dependent manner. Finally, we found that TIGIT is similarly upregulated in a chronic variable stress model in which animals are exposed to unpredictable heterotypic stressors without developing habituation. Taken together, our findings link, for the first time to our knowledge, GR signaling to TIGIT expression. We propose that glucocorticoid hormones dampen immune responses, in part, by enhancing TIGIT expression across multiple critical subsets of effector lymphocytes, including innate-like T cells. Therefore, TIGIT may constitute an attractive target in immune-enhancing interventions for sustained physiological stress.

Factors That Influence the Immune Response to Vaccination

There is substantial variation between individuals in the immune response to vaccination. In this review, we provide an overview of the plethora of studies that have investigated factors that influence humoral and cellular vaccine responses in humans. These include intrinsic host factors (such as age, sex, genetics, and comorbidities), perinatal factors (such as gestational age, birth weight, feeding method, and maternal factors), and extrinsic factors (such as preexisting immunity, microbiota, infections, and antibiotics). Further, environmental factors (such as geographic location, season, family size, and toxins), behavioral factors (such as smoking, alcohol consumption, exercise, and sleep), and nutritional factors (such as body mass index, micronutrients, and enteropathy) also influence how individuals respond to vaccines. Moreover, vaccine factors (such as vaccine type, product, adjuvant, and dose) and administration factors (schedule, site, route, time of vaccination, and coadministered vaccines and other drugs) are also important. An understanding of all these factors and their impacts in the design of vaccine studies and decisions on vaccination schedules offers ways to improve vaccine immunogenicity and efficacy.

Personality traits, patient-centered health status and prognosis of brain tumor patients

Personality traits can be related to prognosis of cancer patients. The study aimed to evaluate the association of big-five personality dimensions with emotional and cognitive health status, and prognosis of brain tumor patients. A total of 178 patients admitted for brain tumor surgery were evaluated for personality traits (Tem item Personality Inventory), depressive/anxiety symptoms (Hospital Anxiety and Depression Scale or HADS) and cognitive functioning (Mini Mental State Examination or MMSE) on admission. One-hundred and forty-three patients were re-evaluated (HADS and MMSE scales) at hospital discharge. Follow-up continued until November, 2015. Thirty-five patients were diagnosed with high-grade glioma, 15 with low-grade glioma and 128 with benign brain tumors (meningioma, pituitary adenoma and vestibular schwannoma). In multivariate regression analyses adjusted for age, gender, past brain tumor treatment, psychiatric histories and medication use, and education, greater TIPI-Extroversion score was associated with greater admission MMSE score (β = 0.159); TIPI-Emotional stability score, with lower HADS-Depression and HADS-Anxiety scores on admission (β = - 0.407 and β = - 0.404, respectively) and at discharge (β = - 0.404 and β = - 0.319, respectively); and greater TIPI-Openness score, with lower admission HADS-D score (β = - 0.255, p = 0.001). In benign brain tumor patients, greater TIPI-Openness score was associated with reduced mortality risk [HR = 0.554 95% CI (0.376-0.814) p = 0.003)] independently from age, gender and histological diagnosis. Personality traits were not associated with survival of high-grade and low-grade glioma patients. Emotional stability and openness are associated with lower depressive/anxiety symptom severity, and extroversion with better cognitive functioning independently from demographic and clinical risk factors. Openness predicts lower mortality risk of low-grade/benign brain tumor patients.

The Vaccination Model in Psychoneuroimmunology Research: A Review

This chapter explores the reasoning behind using the vaccination model to examine the influence of psychosocial factors on immunity. It then briefly discusses the mechanics of the vaccination response and the protocols used in psychoneuroimmunology vaccine research, before giving examples from the research literature of the studies examining relationships such as the association between stress and vaccination response. It also explores the ways the vaccination model can be used to answer key questions in psychoneuroimmunology, such as the following: "Does it matter when stressful life events occur relative to when the vaccine is received?" "What are the effects of prior exposure to the antigen?" "Do other psychosocial factors influence vaccine response besides stress?" Finally, it briefly considers the mechanisms underlying psychosocial factors and vaccination response associations and the future research needed to understand these better, and indeed to use current and future knowledge to improve and enhance vaccine responses in key at-risk populations.

Early-life Socio-economic Status and Adult Health: The Role of Positive Affect

The aim of this paper is to develop a further understanding of the relationship between early-life socio-economic status (SES) and adult health disparities. This was accomplished through evaluation of state indicators of positive and negative affect as mechanisms through which early-life SES was associated with susceptibility to a rhinovirus (i.e. the common cold). Analyses were conducted among 286 adults in a viral challenge study in which participants were exposed to a rhinovirus via nasal drops and cold symptoms were evaluated over a period of 5 days. Participant age, body mass index, sex, education, ethnicity, pre-challenge virus-specific antibody titres and subjective adult SES, along with virus type and season of participation, were included as covariates. Early-life SES was associated with cold incidence through state positive affect, but not state negative affect. In addition, contrast analysis indicated that the indirect effect through state positive affect was stronger than the indirect effect through state negative affect. Findings provide further support for early-life SES being an important variable associated with adult health, and that state self-reported positive affect may be an underlying mechanism associated with susceptibility to rhinoviruses. Copyright © 2016 John Wiley & Sons, Ltd.

Does waterfall aerosol influence mucosal immunity and chronic stress? A randomized controlled clinical trial

BACKGROUND

The specific microclimate of alpine waterfalls with high levels of ionized water aerosols has been suggested to trigger beneficial immunological and psychological effects. In the present three-armed randomized controlled clinical study, we focused on effects on (i) immunological reagibility, on (ii) physiological stress responses, and on (iii) stress-related psychological parameters.

METHODS

People with moderate to high stress levels (n = 65) spent an active sojourn with daily hiking tours in the National Park Hohe Tauern (Großkirchheim, Austria). Half of the group was exposed to water aerosol of an alpine waterfall for 1 h/day (first arm, n = 33), whereas the other half spent the same time at a distant site (second arm, n = 32). A third arm (control, n = 26) had no intervention (except vaccination) and stayed at home, maintaining their usual lifestyle. The effect of the interventions on the immune system was tested by oral vaccination with an approved cholera vaccine and measuring specific salivary IgA antibody titers. Lung function was determined by peak expiratory flow measurement. Electric skin conductance, heart rate, and adaption of respiration rate were assessed as physiological stress parameters. Psychological stress-related parameters were analyzed by questionnaires and scales.

RESULTS

Compared to the control group, both intervention groups showed improvement of the lung function and of most physiological stress test parameters. Analysis of the mucosal immune response revealed a waterfall-specific beneficial effect with elevated IgA titers in the waterfall group. In line with these results, exposure to waterfall revealed an additional benefit concerning psychological parameters such as subjective stress perception (measured via visual analog scale), the Global Severity Index (GSI), and the Positive Symptom Total (PST).

CONCLUSIONS

Our study provides new data, which strongly support an "added value" of exposure to waterfall microclimate when combined with a therapeutic sojourn at high altitude including regular physical activity.

Blood gene expression profiles suggest altered immune function associated with symptoms of generalized anxiety disorder

Prospective epidemiological studies found that generalized anxiety disorder (GAD) can impair immune function and increase risk for cardiovascular disease or events. Mechanisms underlying the physiological reverberations of anxiety, however, are still elusive. Hence, we aimed to investigate molecular processes mediating effects of anxiety on physical health using blood gene expression profiles of 336 community participants (157 anxious and 179 control). We examined genome-wide differential gene expression in anxiety, as well as associations between nine major modules of co-regulated transcripts in blood gene expression and anxiety. No significant differential expression was observed in women, but 631 genes were differentially expressed between anxious and control men at the false discovery rate of 0.1 after controlling for age, body mass index, race, and batch effect. Gene set enrichment analysis (GSEA) revealed that genes with altered expression levels in anxious men were involved in response of various immune cells to vaccination and to acute viral and bacterial infection, and in a metabolic network affecting traits of metabolic syndrome. Further, we found one set of 260 co-regulated genes to be significantly associated with anxiety in men after controlling for the relevant covariates, and demonstrate its equivalence to a component of the stress-related conserved transcriptional response to adversity profile. Taken together, our results suggest potential molecular pathways that can explain negative effects of GAD observed in epidemiological studies. Remarkably, even mild anxiety, which most of our participants had, was associated with observable changes in immune-related gene expression levels. Our findings generate hypotheses and provide incremental insights into molecular mechanisms mediating negative physiological effects of GAD.

Neuroendocrine regulation of inflammation

The interaction between the sympathetic nervous system and the immune system has been documented over the last several decades. In this review, the neuroanatomical, cellular, and molecular evidence for neuroimmune regulation in the maintenance of immune homeostasis will be discussed, as well as the potential impact of neuroimmune dysregulation in health and disease.

The role of the innate immune system in psychiatric disorders

There is by now substantial clinical evidence for an association between specific mood disorders and altered immune function. More recently, a number of hypotheses have been forwarded to explain how components of the innate immune system can regulate brain function at the cellular and systems levels and how these may underlie the pathology of disorders such as depression, PTSD and bipolar disorder. In this review we draw reference to biochemical, cellular and animal disease models, as well as clinical observations to elucidate the role of the innate immune system in psychiatric disorders. Proinflammatory cytokines, such as IL-1β IL-6 and TNFα, which feature prominently in the immune response to pathogen in the periphery, have unique and specific actions on neurons and circuits within the central nervous system. Effects of these signaling molecules on neurotransmission, memory, and glucocorticoid function, as well as animal behaviors such as social withdrawal and fear conditioning relevant to psychiatric disorders are elucidated. Finally, we highlight future directions for studies, including the use of peripheral biomarkers, relevant for developing new therapeutic approaches for treating psychiatric illnesses. This article is part of Special Issue entitled 'neuroinflammation in neurodegeneration and neurodysfunction'.

The vaccination model in psychoneuroimmunology research: a review

This chapter explores the reasoning behind using the vaccination model to examine the influence of psychosocial factors on immunity. It then briefly discusses the mechanics of the vaccination response and the protocols used in Psychoneuroimmunology vaccine research, before giving examples from the research literature of the studies examining relationships such as the association between stress and the vaccination response. It also explores the ways the vaccination model can be used to answer key questions in Psychoneuroimmunology, such as: "does it matter when stressful life events occur relative to when the vaccine is received?" "what are the effects of prior exposure to the antigen?" and "do other psychosocial factors influence vaccine response besides stress?" Finally, it briefly considers the mechanisms underlying psychosocial factors and vaccination response associations and the future research needed to understand these better, and indeed to use current and future knowledge to improve and enhance vaccine responses in key at risk populations.

Immune dysregulation in chronic stress: a quantitative and functional assessment of regulatory T cells

OBJECTIVE

Chronic stress is closely related to immune dysfunction. Immune parameters have been analyzed in many ways in humans and animals under chronic stress. Recently, it has been proved that FoxP3+ regulatory T cells (Tregs) play a key role in immune regulation in vivo. However, it has not yet been elucidated how Tregs respond to chronic stress in vivo. Therefore, in the present study, we investigated the frequency of and functional changes in Tregs from mice under chronic stress.

METHODS

Spleen cells were separated from C57/BL6 mice that had been exposed to immobilization stress for 3 weeks. The frequencies of FoxP3+ and CD4+ CD25+ cells were analyzed by flow cytometry. CD4+CD25- cells (effector T cells, Teffs), CD4+CD25+ cells (Tregs) and CD4- cells (antigen-presenting cells, APCs) were separated for the functional assessment of the proliferative activity of Teffs, the suppressive activity of Tregs and the feeder activity of APCs.

RESULTS

The results showed that chronic immobilization stress significantly increased the frequencies of CD4+CD25+ and CD4+FoxP3+ cells. Chronic immobilization stress also enhanced the suppressive function of CD4+ CD25+ Tregs. On the other hand, the proliferative activity of Teffs and the feeder activity of APCs were decreased in the mice under chronic immobilization stress.

CONCLUSION

Taken together, it is suggested that increased number and function of Tregs may actively contribute to the immune dysfunction in chronic immobilization stress, synergizing with the decreased function of Teffs and APCs.

A neuroimmunological perspective on anxiety disorders

OBJECTIVE

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, the presence of inflammatory responses and the crucial role of cytokines in major depression have been addressed in numerous studies. However, neuroinflammatory hypotheses in anxiety disorders have been studied less extensively than in major depression. There is a high research need for better understanding of both the heterogeneous role of specific cytokines in the control of anxious states and in different anxiety disorders and of the immunomodulating effects of antidepressants on anxiety.

METHODS

Relevant literature was identified through a search of MEDLINE via PubMed. We discuss recent research on neuroimmunology in anxiety and make methodological recommendations for future investigation of neuroinflammatory hypotheses in anxiety disorders.

RESULTS

Some accumulating evidence has indicated modulatory effects of cytokines on neuronal communication and anxiety; however, research has not revealed consistent reproducible findings.

CONCLUSIONS

The availability of inflammatory biomarkers may provide an opportunity to identify patients via specific pathophysiological processes and to monitor therapeutic responses within relevant pathways. Further understanding of the neuroimmunological mechanisms to untangle the reciprocal associations between inflammation and anxiety is warranted.

Population levels of psychological stress, herpesvirus reactivation and HIV

Nearly 40,000 Americans are newly infected with Human Immunodeficiency Virus (HIV) each year. Recently, studies have demonstrated associations between group-level characteristics and the prevalence and incidence of HIV/Acquired Immune Deficiency Syndrome (AIDS) and other sexually transmitted diseases. Two mechanisms previously posited to explain these associations are neighborhood effects on risk behaviors and social or institutional policies. In this paper, we hypothesize that adversity at the population level, such as neighborhood poverty, also influences HIV risk through stress-mediated aberrations in immunological susceptibility by reviewing existing data examining each of these pathways. In particular, we review the evidence showing that: (1) Neighborhood ecologic stressors influence neighborhood- and individual-levels of mental health, psychosocial stress, and HIV/AIDS risk, (2) Individual-level psychosocial stressors influence progression from HIV to AIDS through stress-related hormonal changes, and (3) Individual-level psychosocial stressors influence HIV acquisition via stress-related reactivation of latent herpesviruses, specifically EBV and HSV-2. Our review indicates that further studies are needed to examine the joint pathways linking neighborhood-level sources of psychosocial stress, stress-related reactivation of HSV-2 and EBV, and increased acquisition rates of HIV. We suggest using a multi-level framework for targeting HIV prevention efforts that address not only behavioral risk factors, but structural, political, and institutional factors associated with neighborhood disadvantage, levels of psychosocial stress, and prevention or treatment of HSV-2 and EBV.

Infection, vaccination, and autoantibodies in chronic fatigue syndrome, cause or coincidence?

Chronic fatigue syndrome (CFS) is a heterogeneous syndrome of unknown etiology and physiopathology. CFS patients complain about disabling fatigue, depression, difficulty with memory, and concomitant skeletal and muscular pain. Interestingly enough, there is certain overlap between CFS symptoms, autoimmune rheumatic disease, and infectious diseases. Certain neuroendocrine-immune abnormalities have also been described, and autoantibodies commonly described in some autoimmune diseases have been found in CFS patients as well. An increasing number of autoantibodies, mainly directed against other nuclear cell components, have been illustrated. Likewise, an association between some infectious agents, antibody production, and later CFS onset has been reported. Similarly, vaccination is depicted as playing an important role in CFS onset. Recently, a case report pointed toward a causal association between silicone breast linkage, hepatitis B virus vaccination, and CFS onset in a previous healthy woman. Such findings suggest that there is a likely deregulation of the immune system influenced by specific agents (infections, vaccination, and products, such as silicone). Evidence suggests that CFS is a complex disease in which several risk factors might interact to cause its full expression. Thus, although different alterations have been found in CFS patients, undoubtedly the main feature is central nervous system involvement with immunological alterations. Therefore, a new term neuro-psycho-immunology must be quoted. New studies based on this concept are needed in order to investigate syndromes, such as CFS, in which immunological alterations are thought to be associated with concomitant psychological and health disturbances.

Cardiovascular activity and the antibody response to vaccination

OBJECTIVE

To examine the relationship between cardiovascular activity in response to acute psychological stress and the antibody response to vaccination.

METHODS

Fifty-seven healthy participants were vaccinated with the trivalent influenza vaccine and meningococcal A+C polysaccharides. Antibody levels were measured at baseline and 5-weeks post-vaccination. Cardiovascular activity was measured at rest, during, and following a mental arithmetic stress task in 54 participants.

RESULTS

Participants demonstrating a fourfold increase in antibody titre to the A/Panama and B/Shangdong influenza strains and to meningococcal A showed greater blood pressure reactions toward the end of the acute stress task. In addition, there was some evidence of delayed diastolic blood pressure recovery in those who were responders to A/Panama and B/Shangdong influenza strains.

CONCLUSION

The present results suggest that heightened cardiovascular reactivity to stress and delayed recovery may not necessarily be detrimental to all aspects of health and may be associated with an enhanced immune response to antigen challenge.

[Psychological stress, immune function and disease development. The psychoneuroimmunologic perspective]

Interdisciplinary psychoneuroimmunological (PNI) research increasingly demonstrates clinically relevant interrelations between psychological stressors and the onset or progression of chronic diseases. Disturbances of the bi-directional interaction between the nervous system, the immune system and the endocrine system have been hypothesized to be implicated in several diseases. Here, we review evidence from psychoneuroimmunology within the theoretical framework of allostatic load to conceptualize some of these associations. Interdisciplinary PNI research investigating the importance of psychological stress for the higher incidence of infections, decreased responses to vaccinations and delayed wound healing is reviewed. Furthermore, the literature supporting similar associations with regard to progression of oncological diseases and autoimmune disorders is reviewed with a focus on breast cancer and multiple sclerosis. The accumulating evidence regarding the importance of neuroendocrine-immune interaction in these diseases may thus lead to novel insights into pathogenetic mechanisms and could contribute to the development of novel preventive and therapeutic strategies.

Stress-induced immune dysfunction: implications for health

Folk wisdom has long suggested that stressful events take a toll on health. The field of psychoneuroimmunology (PNI) is now providing key mechanistic evidence about the ways in which stressors--and the negative emotions that they generate--can be translated into physiological changes. PNI researchers have used animal and human models to learn how the immune system communicates bidirectionally with the central nervous and endocrine systems and how these interactions impact on health.

Negative affectivity and enhanced symptom reports: differentiating between symptoms in men and women

This study aimed to characterize individual bodily symptoms as regards their differential relationship with negative affectivity (NA). In a first step, 73 symptoms were rated by independent groups of raters (psychologists, medical doctors, healthy students) on the following characteristics: the extent to which a symptom (1) refers to a specific location in the body (vagueness), (2) may refer to both a physical condition and a negative emotional state (overlap), and (3) is likely to be a physiological manifestation of anxiety (anxiety). Each symptom was also rated on (4) the probability that it is caused by a clearly defined somatic pathology (somatic pathology), (5) how life-threatening or (6) compromising for the quality of life a symptom is, and (7) how worried one would be if the symptom were to be experienced in daily life (worrying). Two factors, severity and somatic versus psychic, explained 75% of the variance in the ratings on the symptom characteristics. Next, based on the data of 1017 university students (858 women), correlations of each individual symptom with NA were calculated for each gender. The pattern of correlation was highly variable and differed in important ways for men and women. Whereas the correlation of an individual symptom with NA could be predicted by both symptom factors in women (R(2)=52%), only the somatic versus psychic factor was a significant predictor in men (R(2)=11%). These results suggest that (1) NA should not be considered a general complaining factor, and (2) important gender differences exist regarding the type of symptoms that relate most strongly to NA.

Neuroticism, cortisol reactivity, and antibody response to vaccination

This study examined whether neuroticism was related to the antibody response to influenza vaccination and whether the relationship was mediated by cortisol reactions to acute laboratory mental stress. Antibody status was assessed at baseline and to a trivalent influenza vaccination in 57 students at 5-week and 5-month follow-up. Neuroticism was also measured at baseline. Cortisol was measured at rest and in response to a pressurized mental arithmetic task. At both follow-ups, higher neuroticism scores were associated with poorer A/Panama antibody response, following adjustment for baseline antibody titer. Higher neuroticism scores were also associated with blunted cortisol reactivity, and blunted cortisol reactivity was associated with poorer A/Panama antibody response, but only at 5 months. However, there was no conclusive evidence that cortisol reactivity mediated the association between neuroticism and antibody response.

Life events, perceived stress and antibody response to influenza vaccination in young, healthy adults

OBJECTIVES

Chronic stress has been associated with impaired response to influenza vaccination in the elderly. This study investigated whether mild, intermittent stress experienced by young, healthy adults has a similar effect.

METHODS

Antibody and psychological status were determined prevaccination and 5 weeks and 5 months later; a fourfold increase in antibody to at least one viral strain was considered protective.

RESULTS

At 5 months, unprotected participants reported significantly more life events and tended to report more perceived stress than those who were protected.

CONCLUSIONS

Psychological stress is detrimental to long-term maintenance of antibody levels following vaccination in young, healthy adults.

Antibody response to vaccination and psychosocial stress in humans: relationships and mechanisms

The purpose of this review is to determine the effects of psychosocial stress on antibody response to vaccination in humans, consider possible mechanisms, and identify agenda for future research. Studies of the association between stress and vaccination response in humans were reviewed. There is evidence of a negative association between stress and antibody response to vaccination, which is most apparent with thymus-dependent vaccines and when measured at extended times after vaccination. Preliminary findings implicate the hypothalamic-pituitary-adrenal axis and sympathetic nervous system as potential mechanisms, although a role for unhealthy behaviours cannot be discounted at this stage. Results to date are sufficiently indicative to direct future research to untangling their theoretical ramifications, as well as realising their clinical implications.

Personality traits predict self-referral of young male adults with musculoskeletal complaints to a general practitioner

OBJECTIVE

To investigate the effects of personality traits on self-referral to a general practitioner (GP).

METHODS

217 male soldiers who underwent advanced training course filled the Eysenck Personality Questionnaire-Revised (EPQ-R) and the Perceived Stress Scale and were followed up for a period of 14 weeks. Every soldier who self-referred to the clinic was physically examined by a GP. The major complaint and the GP's diagnosis were documented.

RESULTS

106 of the 217 soldiers self-referred. Self-referred soldiers had significantly (P=.02) higher levels of extraversion than soldiers who did not. Specifically, higher levels of extraversion were evident among soldiers who self-referred with musculoskeletal complaints (P<.05). No significant difference in stress levels was found between soldiers who self-referred and those who did not.

CONCLUSIONS

These findings underscore the association between extraversion and musculoskeletal complaints among young adult males and suggest that psychological variables should be taken under consideration in the prevention and treatment of orthopedic problems.

Gender and health in rural China: evidence from Hebei Province

Gender differences in health and health behavior are well established in Western societies, but little is known about gender health inequalities in rural China. We examine patterns of age-sex differences in health and health behavior of men and women in rural HeBei, People's Republic of China, and consider the extent to which these patterns resemble gender health inequalities observed in North America and Western Europe. The data analyzed were collected from 14,895 individuals residing in 288 villages in the HeBei Province. The results show that gender differences emerged at a later age than generally reported in Western societies. Poorer health among women, as compared with men, becomes observable during young adulthood (25-44) rather than at adolescence, and reached its peak among older adults (45-59) rather than during the productive and reproductive stage of the life course. Among the elderly, the differences between the health and the health behavior of men and women narrowed, similar to many reports in North America and Western Europe. Most importantly, no gender differences in mental health were observed. These findings suggest that the older adult age group (45-59) may be appropriate for interdisciplinary efforts to advance the understanding regarding the relative contributions of nature and nurture to gender differences in health.

Psychoneuroimmunology: psychological influences on immune function and health

This review focuses on human psychoneuroimmunology studies published in the past decade. Issues discussed include the routes through which psychological factors influence immune function, how a stressor's duration may influence the changes observed, individual difference variables, the ability of interventions to modulate immune function, and the health consequences of psychosocially mediated immune dysregulation. The importance of negative affect and supportive personal relationships are highlighted. Recent data suggest that immune dysregulation may be one core mechanism for a spectrum of conditions associated with aging, including cardiovascular disease, osteoporosis, arthritis, Type 2 diabetes, certain cancers, and frailty and functional decline; production of proinflammatory cytokines that influence these and other conditions can be stimulated directly by negative emotions and indirectly by prolonged infection.

Emotions, morbidity, and mortality: new perspectives from psychoneuroimmunology

Negative emotions can intensify a variety of health threats. We provide a broad framework relating negative emotions to a range of diseases whose onset and course may be influenced by the immune system; inflammation has been linked to a spectrum of conditions associated with aging, including cardiovascular disease, osteoporosis, arthritis, type 2 diabetes, certain cancers, Alzheimer's disease, frailty and functional decline, and periodontal disease. Production of proinflammatory cytokines that influence these and other conditions can be directly stimulated by negative emotions and stressful experiences. Additionally, negative emotions also contribute to prolonged infection and delayed wound healing, processes that fuel sustained proinflammatory cytokine production. Accordingly, we argue that distress-related immune dysregulation may be one core mechanism behind a large and diverse set of health risks associated with negative emotions. Resources such as close personal relationships that diminish negative emotions enhance health in part through their positive impact on immune and endocrine regulation.

Chronic fatigue syndrome: an update

The chronic fatigue syndrome is characterised by a fatigue that is disproportionate to the intensity of effort that is undertaken, has persisted for 6 months or longer, and has no obvious cause. Unless there has been a long period of patient- or physician-imposed inactivity, objective data may show little reduction in muscle strength or peak aerobic power, but the affected individual avoids heavy activity. The study of aetiology and treatment has been hampered by the low disease prevalence (probably <0.1% of the general population), and (until recently) by a lack of clear and standardised diagnostic criteria. It is unclear how far the aetiology is similar for athletes and nonathletes. It appears that in top competitors, overtraining and/or a negative energy balance can be precipitating factors. A wide variety of other possible causes and/or precipitating factors have been cited in the general population, including psychological stress, disorders of personality and affect, dysfunction of the hypothalamic-pituitary-adrenal axis, hormonal imbalance, nutritional deficits, immune suppression or activation and chronic infection. However, none of these factors have been observed consistently. The prognosis is poor; often disability and impairment of athletic performance are prolonged. Prevention of overtraining by careful monitoring seems the most effective approach in athletes. In those where the condition is established, treatment should aim at breaking the vicious cycle of effort avoidance, deterioration in physical condition and an increase in fatigue through a combination of encouragement and a progressive exercise programme.

Psychological stress and antibody response to immunization: a critical review of the human literature

OBJECTIVE

The objective of this review was to evaluate the evidence for the hypothesis that psychological stress influences antibody response to immunization in humans.

METHODS

A critical review of the literature was conducted.

RESULTS

The evidence supports an association between psychological stress and suppression of humoral immune (antibody) response to immunization. This association is convincing in the case of secondary immune response but weak for primary response. The lack of consistent evidence for a relation with primary response may be attributed to a failure to consider the critical points when stress needs to be elevated in the course of the production of antibody. Lower secondary antibody responses were found among patients with chronically high levels of stress (severe enduring problems or high levels of trait negative affect). These responses were found most consistently among older adults. Lower secondary responses were also found for those reporting acute stress or negative affect, but only in studies of secretory immunoglobulin A antibody in which psychological and antibody measures were linked very closely in time. Health practices did not mediate relations between stress and antibody responses; however, there were indications that elevated cortisol levels among stressed patients could play a role. Evidence also suggests the possible influences of dispositional stress-reactivity and low positive affect in the inhibition of antibody production.

CONCLUSIONS

The literature supports a relationship between psychological stress and antibody responses to immunizations. The data are convincing in the case of secondary response but weak for primary response. More attention to the kinetics of stress and antibody response and their interrelations is needed in future research.