Psychological stress affects response to sublingual immunotherapy in asthmatic children allergic to house dust mite

Resting state functional connectivity changes following mindfulness-based stress reduction predict improvements in disease control for patients with asthma

BACKGROUND

The staggering morbidity associated with chronic inflammatory diseases can be reduced by psychological interventions, including Mindfulness-Based Stress Reduction (MBSR). Proposed mechanisms for MBSR's beneficial effects include changes in salience network function. Salience network perturbations are also associated with chronic inflammation, including airway inflammation in asthma, a chronic inflammatory disease affecting approximately 10% of the population. However, no studies have examined whether MBSR-related improvements in disease control are related to changes in salience network function.

METHODS

Adults with asthma were randomized to 8 weeks of MBSR or a waitlist control group. Resting state functional connectivity was measured using fMRI before randomization, immediately post-intervention, and 4 months post-intervention. Using key salience network regions as seeds, we calculated group differences in change in functional connectivity over time and examined whether functional connectivity changes were associated with increased mindfulness, improved asthma control, and decreased inflammatory biomarkers.

RESULTS

The MBSR group showed greater increases in functional connectivity between salience network regions relative to the waitlist group. Improvements in asthma control correlated with increased functional connectivity between the salience network and regions important for attention control and emotion regulation. Improvements in inflammatory biomarkers were related to decreased functional connectivity between the salience network and other networks.

CONCLUSIONS

Increased resting salience network coherence and connectivity with networks that subserve attention and emotion regulation may contribute to the benefits of MBSR for patients with asthma. Understanding the neural underpinnings of MBSR-related benefits in patients is a critical step towards optimizing brain-targeted interventions for chronic inflammatory disease management.

The impact of environmental injustice and social determinants of health on the role of air pollution in asthma and allergic disease in the United States

There is clear evidence that exposure to environmental air pollution is associated with immune dysregulation, asthma, and other allergic diseases. However, the burden of air pollution exposure is not equally distributed across the United States. Many social and environmental factors place communities of color and people who are in poverty at increased risk of exposure to pollution and morbidity from asthma and allergies. Here, we review the evidence that supports the relationship between air pollution and asthma, while considering the social determinants of health that contribute to disparities in exposures and outcomes.

Therapeutic Potential of HLA-I Polyreactive mAbs Mimicking the HLA-I Polyreactivity and Immunoregulatory Functions of IVIg

HLA class-I (HLA-I) polyreactive monoclonal antibodies (mAbs) reacting to all HLA-I alleles were developed by immunizing mice with HLA-E monomeric, α-heavy chain (αHC) open conformers (OCs). Two mAbs (TFL-006 and TFL-007) were bound to the αHC's coated on a solid matrix. The binding was inhibited by the peptide 117AYDGKDY123, present in all alleles of the six HLA-I isoforms but masked by β2-microglobulin (β2-m) in intact HLA-I trimers (closed conformers, CCs). IVIg preparations administered to lower anti-HLA Abs in pre-and post-transplant patients have also shown HLA-I polyreactivity. We hypothesized that the mAbs that mimic IVIg HLA-I polyreactivity might also possess the immunomodulatory capabilities of IVIg. We tested the relative binding affinities of the mAbs and IVIg for both OCs and CCs and compared their effects on (a) the phytohemagglutinin (PHA)-activation T-cells; (b) the production of anti-HLA-II antibody (Ab) by B-memory cells and anti-HLA-I Ab by immortalized B-cells; and (c) the upregulation of CD4+, CD25+, and Fox P3+ T-regs. The mAbs bound only to OC, whereas IVIg bound to both CC and OC. The mAbs suppressed blastogenesis and proliferation of PHA-activated T-cells and anti-HLA Ab production by B-cells and expanded T-regs better than IVIg. We conclude that a humanized version of the TFL-mAbs could be an ideal, therapeutic IVIg-mimetic.

The interplay between neuroendocrine activity and psychological stress-induced exacerbation of allergic asthma

Psychological stress is recognized as a key factor in the exacerbation of allergic asthma, whereby brain responses to stress act as immunomodulators for asthma. In particular, stress-induced enhanced type 2 T-helper (Th2)-type lung inflammation is strongly associated with asthma pathogenesis. Psychological stress leads to eosinophilic airway inflammation through activation of the hypothalamic-pituitary-adrenal pathway and autonomic nervous system. This is followed by the secretion of stress hormones into the blood, including glucocorticoids, epinephrine, and norepinephrine, which enhance Th2 and type 17 T-helper (Th17)-type asthma profiles in humans and rodents. Recent evidence has shown that a defect of the μ-opioid receptor in the brain along with a defect of the peripheral glucocorticoid receptor signaling completely disrupted stress-induced airway inflammation in mice. This suggests that the stress response facilitates events in the central nervous and endocrine systems, thus exacerbating asthma. In this review, we outline the recent findings on the interplay between stress and neuroendocrine activities followed by stress-induced enhanced Th2 and Th17 immune responses and attenuated regulatory T (Treg) cell responses that are closely linked with asthma exacerbation. We will place a special focus on our own data that has emphasized the continuity from central sensing of psychological stress to enhanced eosinophilic airway inflammation. The mechanism that modulates psychological stress-induced exacerbation of allergic asthma through neuroendocrine activities is thought to involve a series of consecutive pathological events from the brain to the lung, which implies there to be a "neuropsychiatry phenotype" in asthma.

Association between adverse childhood experiences in the home and pediatric asthma

BACKGROUND

Numerous studies suggest that psychosocial factors could contribute to pediatric asthma.

OBJECTIVE

To examine the relation between single and cumulative adverse childhood experiences (ACEs), a measurement of household dysfunction, on parent report of lifetime asthma in children.

METHODS

This cross-sectional study used data from the 2011 to 2012 National Survey of Children's Health, a nationally representative sample of children 0 to 17 years old (n = 92,472). The main exposure was parent or guardian report of 6 ACE exposures (eg, witnessing domestic violence). The relation between ACE exposures and parent-reported diagnosis of childhood asthma was examined using multivariable logistic regression after controlling for demographic, socioeconomic, and behavioral covariates.

RESULTS

Overall asthma prevalence was 14.6%. Exposure prevalence to any ACE was 29.2%. Increased number of ACE exposures was associated with increased odds of asthma. In the adjusted model, the odds of reporting asthma were 1.28 (95% confidence interval [CI] 1.14-1.43) for those reporting 1 ACE, 1.73 (95% CI 1.27-2.36) for those with 4 ACEs, and 1.61 (95% CI 1.15-2.26) for those with 5 or 6 ACEs compared with those with no ACE exposures. Effects were moderated by Hispanic ethnicity. Hispanic children exposed to 4 ACEs had a 4.46 times increase in lifetime asthma (95% CI 2.46-8.08); white children had a 1.19 times increase (95% CI 0.80-1.79) compared with those exposed to 0 ACE.

CONCLUSION

This study supports the growing evidence for the biopsychosocial model of asthma onset. Future studies should examine the association between ACEs and specific asthma-related health outcomes.

Parental stress and the onset and course of childhood asthma

The influence of a caregiver’s stress on the development of childhood asthma is an important aspect of the treatment and prevention of illness. Many cross-sectional studies have investigated the association between parenting attitude and/or caregiver’s stress and childhood asthma morbidity, but prospective studies are more advantageous than cross-sectional studies in interpreting a causal relationship from the results. We here present an overview of prospective studies that have reported a relationship between parental stress and the morbidity or course of childhood asthma and discuss the role of parental mental health in its prevention and treatment. Almost all of the studies referred to in this paper show that caregiver (mostly mothers) stress contributed to the onset and to a poor prognosis, while only a few studies have examined the adverse effect of paternal stress on childhood asthma. Their results are inconsistent, and there is insufficient data examining specific stress-related properties that can be targeted in intervention studies. Not only maternal but also paternal influence should be considered in future studies, and it will be important to assess specific stress-related properties that can be the foundation of specific intervention methods.

Clinical and cytokine responses to house dust mite sublingual immunotherapy

BACKGROUND

Cytokine responses accompanying sublingual immunotherapy (SLIT) responder phenotypes have not previously been reported.

OBJECTIVE

To investigate clinical and cytokine responses of house dust mite (HDM) sensitive patients with allergic rhinitis receiving HDM SLIT or placebo for 2 years.

METHODS

Sixty adults were randomized to receive SLIT or placebo. Clinical symptoms were measured using the Total 5 Symptom Score (TSS5) and Juniper Rhinitis Quality of Life Questionnaire. HDM specific IgE, IgG, skin prick tests, and HDM-stimulated release of interleukin (IL) 5 and interferon γ (IFN-γ) in peripheral blood mononuclear cells was studied at 0, 6, 12, and 24 months and IL-13, IL-4, and IL-10 at 0 and 24 months.

RESULTS

A total of 32 of 39 SLIT and 16 of 21 placebo patients completed the study. There was significant clinical improvement in both the SLIT and placebo groups. Median T5SS decreased from 14.75 to 5.25 in the SLIT group (P < .001) and 12.7 to 6.0 in the placebo group (P = .003). The median quality-of-life score also decreased in the SLIT group (P < .001) and the placebo group (P < .001). A subgroup analysis of patients found a 60% or greater improvement (on the T5SS and the Juniper Rhinitis Quality of Life Questionnaire) in the good responders group and a 30% to 59% improvement or no improvement in the intermediate responders group. This subgroup analysis also found more good responders in the SLIT group (47%) compared with the placebo group (25%; P = .07). Significant decreases in the IL-5/IFN-γ (P < .001), IL-13/IFN-γ (P < .001), and IL-4/IFN-γ (P = .03) ratios were found in the combined good clinical improvement group at 24 months.

CONCLUSION

A good clinical response (≥60% improvement in both TSS5 and quality of life) is associated with significant decreases in IL-5, IL-13, and IL-4 relative to IFN-γ during 2 years of SLIT therapy for HDMs.

Stress and obesity as risk factors in cardiovascular diseases: a neuroimmune perspective

Obesity is now growing at an alarming rate reaching epidemic proportions worldwide thus increasing morbidity and mortality rates for chronic disease. But although we have ample information on the complications associated with obesity, precisely what causes obesity remains poorly understood. Some evidence attributes a major role to a low-grade chronic inflammatory state (neurogenic inflammation) induced in obesity by inflammatory mediators produced and secreted within the expanded activated adipocyte pool. Adipose tissue is an endocrine organ that secretes numerous adipose tissue-specific or enriched hormones, known as adipokines, cytokine-like molecules thought to play a pathogenic role in cardiovascular diseases. The imbalance between increased inflammatory stimuli and decreased anti-inflammatory mechanisms may depend on chronic stress. Hence the positive correlation found between stress, obesity and cardiovascular diseases. The chronic inflammatory state associated with insulin resistance and endothelial dysfunction is highly deleterious for vascular function. This review focuses on the proposed neuroimmunodulatory mechanisms linking chronic (psychological) stress, obesity and cardiovascular diseases.

Evolutionary biology and anthropology suggest biome reconstitution as a necessary approach toward dealing with immune disorders

Industrialized society currently faces a wide range of non-infectious, immune-related pandemics. These pandemics include a variety of autoimmune, inflammatory and allergic diseases that are often associated with common environmental triggers and with genetic predisposition, but that do not occur in developing societies. In this review, we briefly present the idea that these pandemics are due to a limited number of evolutionary mismatches, the most damaging being 'biome depletion'. This particular mismatch involves the loss of species from the ecosystem of the human body, the human biome, many of which have traditionally been classified as parasites, although some may actually be commensal or even mutualistic. This view, evolved from the 'hygiene hypothesis', encompasses a broad ecological and evolutionary perspective that considers host-symbiont relations as plastic, changing through ecological space and evolutionary time. Fortunately, this perspective provides a blueprint, termed 'biome reconstitution', for disease treatment and especially for disease prevention. Biome reconstitution includes the controlled and population-wide reintroduction (i.e. domestication) of selected species that have been all but eradicated from the human biome in industrialized society and holds great promise for the elimination of pandemics of allergic, inflammatory and autoimmune diseases.

Stress and the city: housing stressors are associated with respiratory health among low socioeconomic status Chicago children

Asthma disproportionately affects non-whites in urban areas and those of low socioeconomic status, yet asthma's social patterning is not well-explained by known risk factors. We hypothesized that disadvantaged urban populations experience acute and chronic housing stressors which produce psychological stress and impact health through biological and behavioral pathways. We examined eight outcomes: six child respiratory outcomes as well as parent and child general health, using data from 682 low-income, Chicago parents of diagnosed and undiagnosed asthmatic children. We created a continuous exposure, representing material, social and emotional dimensions of housing stressors, weighted by their parent-reported difficulty. We compared the 75th to the 25th quartile of exposure in adjusted binomial and negative binomial regression models. Higher risks and rates of poor health were associated with higher housing stressors for six of eight outcomes. The risk difference (RD) for poor/fair general health was larger for children [RD = 6.28 (95% CI 1.22, 11.35)] than for parents [RD = 3.88 (95% CI -1.87, 9.63)]. The incidence rate difference (IRD) for exercise intolerance was nearly one extra day per 2 weeks for the higher exposure group [IRD = 0.88 (95% CI 0.41, 1.35)]; nearly one-third extra day per 2 weeks for waking at night [IRD = 0.32 (95% CI 0.01, 0.63)]; and nearly one-third extra day per 6 months for unplanned medical visits [IRD = 0.30 (95% CI 0.059, 0.54)]. Results contribute to the conceptualization of urban stress as a "social pollutant" and to the hypothesized role of stress in health disparities. Interventions to improve asthma outcomes must address individuals' reactions to stress while we seek structural solutions to residential stressors and health inequities.

Parent perceptions of neighborhood stressors are associated with general health and child respiratory health among low-income, urban families

BACKGROUND

This cross-sectional study examines parents' perceptions of their neighborhoods and general and respiratory health among low-income Chicago families. Asthma disproportionately affects nonwhite, urban, and low socioeconomic status (SES) populations, but Chicago's burden, and the national epidemic, are not well explained by known risk factors. Urban dwellers experience acute and chronic stressors that produce psychological distress and are hypothesized to impact health through biological and behavioral pathways. Identifying factors that covary with lower SES and minority-group status-e.g., stress-is important for understanding asthma's social patterning.

METHODS

We used survey data from 319 parents of children 5-13 years with asthma/respiratory problems and principal components analysis to create exposure variables representing parents' perceptions of two aspects of neighborhoods: collective efficacy ("CE") and physical/social order ("order"). Adjusted binomial regression models estimated risk differences (RDs) and 95% confidence intervals (CIs) for eight binary outcomes.

RESULTS

Magnitude was generally as expected, i.e., RD for low- versus high- (most favorable) exposure groups (RD(low v. high)) was larger than for the middle versus high contrast (RD(mid v. high)). "Parent general health" was strongly associated with "CE" (RD(low v. high) = 20.8 [95% CI: 7.8, 33.9]) and "order" (RD(mid v. high) = 11.4 [95% CI: 2.1, 20.7]), unlike "child general health," which had nearly null associations. Among respiratory outcomes, only "waking at night" was strongly associated with "CE" (RD(low v. high) = 16.7 [95% CI: 2.8, 30.6]) and "order" (RD(low v. high) = 22.2 [95% CI: 8.6, 35.8]). "Exercise intolerance" (RD(low v. high) = 15.8 [95% CI: 2.1, 29.5]) and "controllability" (RD(mid v. high) = 12.0 [95% CI: 1.8, 22.3]) were moderately associated with "order" but not with "CE," whereas "school absences," "rescue medication use," and "unplanned visits" had nearly null associations with both exposures.

CONCLUSIONS

More negative perceptions tended to be associated with higher risk of undesirable outcomes, adding to evidence that the social environment contributes to health and supporting research on stress' health impact among disadvantaged populations. Interventions must address not only traditional "environmental" factors, but also individuals' reactions to stress and attempt to mitigate effects of stressors while structural solutions to health inequities are sought.

Relation between stressful life events, neuropeptides and cytokines: results from the LISA birth cohort study

Stressful life events evidently have an impact on development of allergic diseases, but the mechanism linking stress to pathological changes of immune system function is still not fully understood. The aim of our study was to investigate the relationship between stressful life events, neuropeptide and cytokine concentrations in children. Within the LISAplus (Life style-Immune system-Allergy) study, blood samples from children of 6 yr of age were analysed for concentration of the neuropeptides vasoactive intestinal peptide (VIP), somatostatin (SOM), substance P (SP) and the Th1/Th2 cytokines interferon-gamma (IFN-gamma) and interleukin (IL)-4. Life events such as severe disease or death of a family member, unemployment or divorce of the parents were assessed with a questionnaire filled in by the parents. For 234 children, blood analysis and questionnaire data regarding life events were available. Children with separated/divorced parents showed high VIP levels and high concentrations of the Th2 cytokine IL-4 in their blood. Severe diseases and death of a family member were neither associated with neuropeptide levels nor with cytokine concentrations. Unemployment of the parents was associated with decreased IFN-gamma concentrations in children's blood but not with neuropeptide levels, whereas children experiencing concomitant severe disease and death of a family member had reduced SP blood levels. The neuropeptide VIP might be a mediator between stressful life events and immune regulation contributing to the Th2 shifted immune response in children with separated/divorced parents. Unemployment of the parents was associated with immune regulation in children on the basis of a still unknown mechanism whereas reduced SP levels seem to have no effect on immune regulation.

Stressful life events and asthma in adolescents

Recent studies suggest that psychosocial factors may contribute to asthma. We examined associations of stressful life events with asthma prevalence and morbidity among Chicago adolescents. Self-reported asthma, measures of asthma morbidity, and 15 life events were collected from 2026 seventh to ninth grade students from 34 Chicago Catholic schools as part of the International Study of Allergies and Asthma in Childhood in 1994-95. Life events were reported by 77% of adolescents and overall asthma prevalence was 15.5%. Stressful life events in adolescents were significantly related to both asthma and asthma morbidity. Odds of asthma was 1.44 (95% confidence interval [CI] = 1.07, 1.95) for those reporting two to three stressful events and 1.92 (95% CI = 1.41, 2.62) for subjects endorsing more than three stressful events. In adolescents with asthma, number of asthma symptoms (odds ratio [OR] for increase in one event = 1.16, 95% CI = 1.07, 1.27), asthma-related school absenteeism (OR = 1.17, 95% CI = 1.04, 1.32), physician visits for asthma (OR = 1.16, 95% CI = 1.04, 1.29), and hospitalization for asthma (OR = 1.20, 95% CI = 1.001, 1.44) were significantly associated with the number of stressful events, independent of home exposure to cigarette smoke and dampness, use of inhaled substances, and sociodemographic factors. While these results are not sufficient to assign causality in the relationship between stress and asthma, they are supported by a number of other studies and by plausible biologic mechanisms. Assessing and addressing the effects of stressful life events may be helpful in managing asthma in inner city adolescents.

Sublingual immunotherapy in pediatric allergic rhinitis and asthma: efficacy, safety, and practical considerations

Specific allergen immunotherapy (SIT) is the only disease-modifying treatment for allergic rhinitis and asthma. Subcutaneous immunotherapy (SCIT) is the only method with a US Food and Drug Administration (FDA)-approved formulation, but safety concerns limit administration to medical facilities. Sublingual immunotherapy (SLIT), under investigation in the United States, appears to have a more favorable safety profile, which may expand its use to populations generally not treated with SIT (eg, young children). This paper reviews SLIT studies that were specifically limited to the pediatric population. Most demonstrated evidence of clinical efficacy, but approximately 29% failed to demonstrate efficacy in symptom and medication scores in the first treatment year. Efficacy was seen in a broad range of allergen doses, but optimal dose range has not been established. SLIT appeared to be well tolerated in children as young as 2 years, but serious adverse reactions, including anaphylaxis, were reported. SLIT is a promising immunotherapy that may expand the population receiving SIT because of the convenience of home administration due to its favorable safety profile. However, questions remain unanswered, including optimal therapeutic dose.