Allostatic load biomarkers and asthma in adolescents

Child marriage as a risk factor for non-communicable diseases among women in India

BACKGROUND

Child marriage, defined as marriage under the age of 18 years, remains pervasive in India. Global evidence documents a negative association between child marriage and women's reproductive and sexual health outcomes; however, its relationship with non-communicable diseases (NCDs) remains underexplored.

METHODS

We utilize biomarkers and self-reported data from the nationally representative National Family and Health Survey 4 (2015-2016) to examine the associations between child marriage and hypertension, diabetes, heart disease, asthma and thyroid disorder among currently married women (N = 421 107). We use regression models adjusted for a range of demographic and socio-economic controls to assess the association between child marriage and NCDs among women in India. We further assess whether and to what extent these relationships are mediated by early motherhood using the Karlson, Holm and Breen method of decomposition.

RESULTS

Child marriage was associated with hypertension [adjusted odds ratio 1.20 (95% CI: 1.17-1.24)], diabetes [1.29 (1.22-1.37)], heart disease [1.27 (1.18-1.36)], asthma [1.19 (1.11-1.28)] and thyroid disorder [1.10 (1.02-1.18)]. Early motherhood also increased the risk of NCDs among women. Furthermore, it emerged as a pathway linking child marriage with hypertension, diabetes and heart disease; however, it provided a partial explanation for the disadvantage associated with child marriages.

CONCLUSIONS

Child marriage emerges as a risk factor for NCDs among women in India. Health systems need to recognize the enduring influence of child marriages on women's health and ensure early detection and effective treatment of NCDs for this vulnerable group.

Allostatic Load in Children and Adolescents: A Systematic Review

INTRODUCTION

The concept of allostatic load encompasses the cumulative effects of both ordinary daily life events as well as major challenges, and also includes related health-damaging behavior. Allostatic overload ensues when environmental challenges exceed the individual's ability to cope. Identification of allostatic load is carried out through the use of biomarkers and clinimetric criteria. Studies are increasingly reported on allostatic load in younger populations, yet a systematic review is missing.

OBJECTIVE

The aim of the present systematic review was to summarize the current knowledge on allostatic load/overload among children and adolescents.

METHODS

PubMed, PsycINFO, Web of Science, and the Cochrane Library were searched from inception to April 2023. A manual search of the literature was also performed. We considered only studies in which allostatic load or overload were adequately described and assessed in either clinical or non-clinical populations younger than 18 years.

RESULTS

A total of 38 original investigations were included in this systematic review. Studies reported an association between allostatic load and sociodemographic characteristics (e.g., poverty, ethnicity, perceived discrimination, adverse childhood experiences) and environmental factors, as well as consequences of allostatic load on both physical and mental health among children and adolescents.

CONCLUSIONS

The findings indicate that greater allostatic load is associated with poorer health outcomes in both clinical and non-clinical pediatric populations, with possible enduring effects. The results support the clinical utility of the transdiagnostic identification of allostatic load and overload in children and adolescents across a variety of settings, with a number of potential clinical implications.

The Association of Cytomegalovirus and Allostatic Load by Country of Birth and Length of Time in the United States

BACKGROUND

Cytomegalovirus (CMV) is a highly prevalent virus with a worldwide distribution. It typically remains dormant in most individuals until reactivation. Immunocompromised states are known to be potential causes for CMV reactivation. Current research has shown a link in the decline of immigrant health among those living in the US for an extended period, though the impact of CMV on this is not clear.

METHODS

This study investigated the association between country of birth, duration of US residency, allostatic load, and latent cytomegalovirus infection (CMV IgG) in a sample of US adults aged 20-49. The data utilized for our analysis was obtained from the National Health and Nutrition Examination Survey (NHANES) conducted between 2001 and 2004. Allostatic load, an index measuring the cumulative physiological strain on the body as it strives to regain stability in the presence of chronic stress, provided a valuable approach to assess stress within the context of CMV exposure. Logistic regression modeling was employed to estimate odds ratios and confidence intervals for the analysis. The chi-square test of association and Cramer's V statistic were used to assess the correlation among categorical variables, while Pearson's correlation coefficient was applied to evaluate the relationship between continuous variables. The results revealed that individuals born outside the US and those with less than 20 years of residency in the US exhibited significantly higher proportions of positive CMV IgG compared to individuals born in the US. Specifically, individuals born outside the US had more than triple the odds of CMV IgG when adjusting for the AL index (OR = 3.69, p-value = 0.0063). A similar trend was observed when examining AL risk based on the duration of US residency. Furthermore, age and sex were identified as significant predictors (p-value < 0.05) of AL risk, considering the individual's country of birth. In summary, the findings of this study significantly enhance our comprehension of the intricate interplay between cytomegalovirus (CMV) and allostatic load (AL). The investigation sheds light on how CMV and AL interact within specific demographic contexts, providing valuable insights into the underlying risk factors for CMV infection.

Biological Burden of Adverse Childhood Experiences in Children

OBJECTIVE

This study aimed to examine relationships between adverse childhood experiences (ACEs) and related life events and allostatic load (AL)-"wear and tear" from chronic stress-in a pediatric population.

METHODS

Children were screened with the PEdiatric ACEs and Related Life Event Screener (PEARLS) tool, a 17-item questionnaire capturing experiences of abuse, neglect, household challenges, and related life events. Biological data were available for 207 participants, and AL was operationalized using clinical or empirical cutoff points across 4 physiological systems (i.e., cardiac, metabolic, inflammatory, neurologic). Covariate-adjusted multivariable regression models were used to examine associations between AL with adversity and health.

RESULTS

Children (mean age = 6.5 years, range = 1-11 years) had an average AL score of 1.9 (standard deviation = 1.7), and a U-shaped relationship was observed with child's age. Continuous PEARLS and original ACE scores were not associated with AL. However, children with a reported PEARLS score of 1 to 2 or original ACEs score of 1 to 3 had 1.5 (incidence rate ratio [IRR] = 1.50, 95% confidence interval [CI] = 1.09-2.08) and 1.4 (IRR = 1.41, 95% CI = 1.08-1.84) times greater AL, respectively, compared with participants with none reported. In secondary analyses, caregiver mental illness was associated with higher child AL (adjusted IRR = 1.27, 95% CI = 1.01-1.58). AL was also associated with poorer perceived child general health (adjusted β = -0.87, 95% CI = -1.58 to -0.15) and greater odds of child obesity (adjusted odds ratio = 1.51, 95% CI = 1.23-1.89).

CONCLUSIONS

Measuring AL in a pediatric population requires careful consideration of age. Higher AL was associated with a greater number of reported adversities and worse child health.

Longitudinal assessment of maternal depression and early childhood asthma and wheeze: Effect modification by child sex

BACKGROUND

Studies report associations between maternal mental health and adverse respiratory outcomes in children; however, the impact of timing and duration of maternal distress remains understudied. We sought to longitudinally examine associations between maternal depression and childhood asthma and wheeze, and explore sex differences.

METHODS

Maternal depression (n = 601) was assessed using the Edinburgh Depression Scale questionnaire, dichotomized at a clinically relevant cutoff (>12) (a) during pregnancy, (b) postpartum, and (c) postpartum and subsequent time points postnatally (recurrent depression). Report of wheeze in the past 12 months (current wheeze) and asthma were obtained using the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire at 48 and 72 months. Associations were analyzed using a modified Poisson regression adjusted for covariates, and in interaction models.

RESULTS

Both postpartum and recurrent depression were associated with higher risk of current wheeze (relative risk [RR]: 1.87, 95% confidence interval [CI]: 1.21, 2.90; RR: 2.41, 95% CI: 1.53, 3.79) and asthma at 48 months (RR: 2.42, 95% CI: 1.01, 5.84; RR: 2.45, 95% CI: 1.02, 5.84). In interaction analyses, associations were stronger in females. Recurrent depression was associated with a higher risk of current wheeze at 48 months in females (RR: 4.34, 95% CI: 2.02, 9.32) when compared to males (RR: 1.89, 95% CI: 1.05, 3.39).

CONCLUSIONS

Postpartum and recurrent depression were associated with a higher risk of wheeze and asthma in children. Understanding the temporal- and sex-specific effects of maternal depression may better inform prevention strategies.

The Association of Cytomegalovirus IgM and Allostatic Load

Background: Cytomegalovirus (CMV) is a deoxyribonucleic acid virus that affects a significant proportion of the worldwide population; after primary infection, it goes into a latent state and can be reactivated, primarily after a reduction in host immune defenses. Methods: This study evaluated the association of acute cytomegalovirus infection (CMV IgM) and Allostatic Load (AL) by sociodemographic factors using data from the National Health and Nutrition Examination Survey (NHANES) 2001–2004 among participants (aged 20–49 years). CMV infection was determined by the level of CMV IgM antibody in serum samples. AL was assessed as a combination of 10 biomarkers from the cardiovascular, inflammatory, and metabolic systems. The evaluation of the association between CMV infection and AL included descriptive statistics and logistic regression models, which were adjusted for demographic and behavioral covariates. Results: AL was more elevated among those who were older, male, those with lower education, those performing limited physical activity, and smokers. CMV was more elevated in females than males among those who consumed alcohol and cigarette smokers. In Pearson’s correlation analysis, there was a slight positive correlation between CMV IgM and AL, with triglycerides and Body Mass Index (BMI) the most strongly correlated with AL. Binary logistic regression showed no significant relationship between high AL and positive CMV IgM but did show a significant relationship between high AL and age (OR = 1.0592, 95% CI 1.0215–1.0983, p = 0.00715). The findings of this study provide insight into the relationship between CMV and AL and provide awareness of factors that affect their relationship.

Clinical Measures of Allostatic Load in Children and Adolescents with Food Allergy, Depression, or Anxiety

PURPOSE

Sustained high stress exposure results in chronic activation of the stress response system, dysregulated stress responses, high allostatic load, and poor later-life health. Children and adolescents with chronic health conditions face stressors related to their condition in addition to those typical of childhood and adolescence, placing them at risk of high allostatic load. The purpose of this secondary analysis was to examine whether youth with chronic health conditions differ from controls on clinical measures of allostatic load.

DESIGN AND METHODS

A secondary analysis of two datasets, the electronic health record of a tertiary children's hospital and data from the Survey of the Health of Wisconsin, compared youth with chronic health conditions to controls on clinical measures of allostatic load. Additional analyses explored whether parental stress and mental health influenced these relationships.

RESULTS

Analyses identified differences in BMI, blood pressure, and waist circumference between youth with food allergy, anxiety, or depression, and controls. These relationships differed for males and females and for those with comorbid mental and physical conditions, and were influenced by parent stress and mental health.

CONCLUSIONS

Results support future studies exploring whether high stress in youth with chronic health conditions leads to increased allostatic load. Incorporating biomarkers as well as genetic and epigenetic factors will provide critical insights.

PRACTICE IMPLICATIONS

Youth with mental and physical CHCs may be at increased risk of high allostatic load, reflected in clinical measures of metabolism, and should have regular assessments of their metabolic health.

Marginal Food Security Predicts Earlier Age at Menarche Among Girls From the 2009-2014 National Health and Nutrition Examination Surveys

STUDY OBJECTIVE

This study analyzed the relationship between household food security and variation in age at menarche, as well as the connections between food insecurity, nutritional status, and allostatic load, among girls aged 12-15 years from the 2009-2014 United States National Health and Nutrition Examination Survey (NHANES).

METHODS

Data analysis included mean comparisons of age at menarche among household food security groups (high, marginal, low, and very low) as well as categorical variables known to associate with age at menarche (ethnicity, poverty status, body mass index [BMI], allostatic load, and milk consumption). χ² Analyses were used to test the associations between household food security and additional categorical variables. Univariate and multivariate regression models were used to test the relationship between variation in age at menarche and household food security, ethnicity, BMI, and allostatic load categories while controlling for age.

RESULTS

Non-Hispanic Black and Hispanic/Mexican American girls had earlier mean ages at menarche, higher mean BMIs, and disproportionately experienced household food insecurity when compared to non-Hispanic White-identifying girls. In the univariate analyses, marginal household food security, Hispanic/Mexican American and Black ethnicities, overweight and obese BMI categories, and marginal-high allostatic load were each associated with lower age at menarche compared to reference categories. These associations were maintained in the multivariate analysis, although only Hispanic/Mexican American ethnicity predicted earlier menarche when compared to that of non-Hispanic White girls.

CONCLUSIONS

Marginal household food security, particularly for girls who identified as non-White, predicted earlier age at menarche independent of nutritional status and allostatic load. At the same time, having more energetic resources (ie, higher BMI) also significantly predicted earlier menarche.

Long-term physical health outcomes of obsessive-compulsive personality disorder traits

BACKGROUND

Obsessive-compulsive personality disorder (OCPD) is characterized by pervasive and persistent traits including preoccupation with orderliness, perfectionism, and control. Relatively little is known about the potential relationship between OCPD traits and physical health.

METHODS

We investigated the association between OCPD traits and several self-reported medical conditions in 249 individuals followed prospectively from 1981 until 2004/2005 as part of the Epidemiological Catchment Area.

RESULTS

The OCPD trait score was inversely related to hypertension in males, in models unadjusted (OR = 0.66; 95% CI, 0.45-0.90) and adjusted (OR = 0.70; 95% CI, 0.47-0.95) for sociodemographic variables. Perfectionism was inversely related to hypertension in the unadjusted models for men (OR = 0.34; 95% CI, 0.12-0.89). Indecisiveness was positively associated with heart conditions in adjusted models for women (OR = 3.46; 95% CI, 1.11-10.52).

CONCLUSION

OCPD traits are associated with cardiovascular health in both sexes. Further studies are needed to understand the specificity of these relationships, as well as to determine the underlying mechanism.

Allostatic load: Developmental and conceptual considerations in a multi-system physiological indicator of chronic stress exposure

Developmental researchers studying how stress affects health have often focused on specific, individual, physiological parameters such as cortisol. Yet, recent theories of stress biology emphasize that the stress response is multi-faceted and engages distinct yet interconnected physiological systems, including metabolic, immune, and cardiovascular systems that respond to one another. Moreover, advocates of a systems approach also argue that the confluence of changes across several physiological systems presents a health risk, even when one indicator alone is not predictive of health outcomes. Allostatic load is one potential multi-system indicator of stress, capturing the cumulative, physiological burden of chronic stress exposure on the body. At the same time, studying allostatic load during early development raises several issues, including how allostatic load is operationalized, the clinical importance of commonly used biomarkers during distinct periods of development, and the fundamental role of timing. In this review paper, we discuss the potential of allostatic load in the context of studies of stress in developmental science, review developmental studies that have assessed allostatic load, and articulate critical conceptual questions regarding the study of allostatic load during the childhood years.

Home environment allergen exposure scale in older adult cohort with asthma

OBJECTIVES

Home environmental exposures are a primary source of asthma exacerbation. There is a gap in decision support models that efficiently aggregate the home exposure assessment scores for focused and tailored interventions. Three development methods of a home environment allergen exposure scale for persons with asthma (weighted by dimension reduction, unweighted, precision biomarker-based) were compared, and racial disparity tested.

METHODS

Baseline measures from a longitudinal cohort of 187 older adults with asthma were analyzed using humidity and particulate matter sensors, allergy testing, and a home environment checklist. Weights for the dimension reduction scale were obtained from factor analysis, applied for loadings > 0.35. Scales were tested in linear regression models with asthma control and asthma quality of life outcomes. Racial disparities were tested using t tests. Scale performance was tested using unadjusted regression analyses with asthma control and asthma quality of life outcomes, separately.

RESULTS

The 7-item empirically weighted scale demonstrated best performance with asthma control associations (F = 4.65, p = 0.03, R2 = .02) and quality of life (F = 6.45, p = 0.01, R2 = .03) as follows: evidence of roach/mice, dust, mold, tobacco smoke exposure, properly venting bathroom fan, self-report of roach/mice/rats, and access to a HEPA filter vacuum. Pets indoors loaded on a separate scale. Racial differences were observed (t = - 3.09, p = 0.004).

CONCLUSION

The Home Environment Allergen Exposure Scale scores were associated with racial disparities. Replicating these methods in populations residing in high-risk/low-income housing may generate a clinically meaningful, tailored assessment of asthma triggers. Further consideration for variables that address allergic reactivity and biomarker results is indicated to enhance the potential for a precision prevention score.

Association between asthma, corticosteroids and allostatic load biomarkers: a cross-sectional study

BACKGROUND

Allostatic load, a measure of early ageing or 'wear and tear' from adapting to environmental challenges, has been suggested as a framework with which to understand the stress-related disruption of multiple biological systems which may be linked to asthma. Considering the socioeconomic context is also critical given asthma and allostatic overload are more common in lower socioeconomic groups.

AIMS

Estimate the relationship between allostatic load and its constituent biomarkers, asthma and corticosteroid prescribing while controlling for socioeconomic status.

METHODS

Data from Understanding Society (a nationally representative survey of UK community-dwelling adults) waves 1-3 (2009-2012) allowed the identification of a sex-specific risk profile across 12 biomarkers used to construct an Allostatic Load Index for a sample of 9816 adults. Regression analyses were used to examine the association of asthma status and corticosteroid prescriptions with allostatic load and its constituent biomarkers while controlling for socioeconomic status (n=9805).

RESULTS

Subjects with currently treated asthma and no corticosteroid prescription have an allostatic load 1.21 times higher than those without asthma (p<0.001). Asthmatic subjects in receipt of inhaled corticosteroids had an allostatic load, approximately 1.12 times higher than those without asthma (p<0.001). This association persisted in sensitivity analyses and appeared to be driven by an association with specific biomarkers (dehydroepiandrosterone-sulfate, waist-to-height ratio and C-reactive protein).

CONCLUSION

Early ageing, in the form of a higher allostatic load, was present even in the mildest asthma group not receiving inhaled corticosteroids. Allostatic load is helpful in understanding the increased all-cause mortality and multimorbidity observed in asthma.

Association between prolonged separation from parents and allostatic load among children in China

OBJECTIVE

To capture the association of exposure to prolonged separation from both parents early in life and allostatic load (AL), a measure of biological multi-system dysregulation.

METHODS

We used data from 557 7-12-year-old children enrolled in rural area of Chizhou city, Anhui Province, China. We computed an AL score based on eleven biomarkers representing four regulatory systems: immune/inflammatory system (high sensitivity C-reactive protein); metabolic system (body mass index; high density lipoprotein; low density lipoprotein, total cholesterol; triglycerides; fasting glucose; glycated hemoglobin; insulin) and cardiovascular system (systolic and diastolic blood pressure). Child's experiences of parent-child separation were collected a brief online questionnaire by parents of children.

RESULTS

More than 1 in 3 of our participants separated with both parents at age 6 or younger and nearly 1 in 10 persistently separated from both parents after birth. The AL score was significantly higher among children separated from both parents during early childhood (3.25 ± 1.98) or persistently since birth (3.48 ± 1.92), compared with those who did not separated from both parents (2.34 ± 1.53, F = 12.992, P<0.001). After adjustment of demographic covariates, body mass index as well as parent frequency of communication and parental warmth, children who separated from both parents in early childhood (β = 0.84, 95%CI:0.40, 1.28, P < 0.001) or persistently into adolescence (β = 1.27, 95%CI:0.43, 2.12, P = 0.003) evinced the highest levels of AL.

CONCLUSION

This study is the first to show an association between prolonged parent-child separation and physiological wear-and-tear as measured by AL, which provides potential insights into the biological mechanisms underpinning long-term health outcomes in contexts of parent-child separation.

Maternal Distress During Pregnancy and Recurrence in Early Childhood Predicts Atopic Dermatitis and Asthma in Childhood

BACKGROUND

Early-life stress is becoming an important determinant of immune system programming. Maternal prenatal distress is found to be associated with atopic disease in offspring but the separate effects of postnatal distress are not well-studied.

RESEARCH QUESTION

Does the likelihood of asthma and atopic dermatitis in children increase when they are exposed to maternal distress pre- and postnatally in a sex-specific manner?

STUDY DESIGN AND METHODS

Using data from a provincial newborn screen and health-care database for 12,587 children born in 2004, maternal distress (depression or anxiety) was defined as prenatal, self-limiting, recurrent, or late-onset postpartum. Atopic dermatitis (AD) and asthma at ages 5 years and 7 years of age were diagnosed by using hospitalization, physician visit, or prescription records. Associations between maternal distress and childhood asthma and AD were determined by using multiple logistic regression.

RESULTS

After adjusting for risk factors, a significant association between maternal prenatal (OR, 1.27; 95% CI, 1.11-1.46), recurrent postpartum (OR, 1.28; 95% CI, 1.11-1.48), and late-onset postpartum (OR, 1.19, 95% CI, 1.06-1.34) distress was found with AD at age 5 years. Asthma at age 7 years was also associated with maternal prenatal distress (OR, 1.57; 95% CI, 1.29-1.91) and late-onset postnatal distress (OR, 1.22; 95% CI, 1.01-1.46). Self-limiting postnatal distress was not found to be a risk factor for either atopic condition. Associations with AD or asthma were of a similar magnitude in boys and girls; the exception was recurrent postnatal distress, which increased risk for asthma in boys only.

INTERPRETATION

This population-based study provides evidence for sex-specific associations between maternal prenatal and postnatal distress, as well as the development of AD and asthma. The findings support recommendations for greater psychosocial support of mothers during pregnancy and early childhood to prevent childhood atopic disease.

Cumulative Impact of Environmental Pollution and Population Vulnerability on Pediatric Asthma Hospitalizations: A Multilevel Analysis of CalEnviroScreen

The CalEnviroScreen created by the Office of Environmental Health Hazard Assessment, Sacramento, USA, is a place-based dataset developed to measure environmental and social indicators that are theorized to have cumulative health impacts on populations. The objective of this study was to examine the extent to which the composite scores of the CalEnviroScreen tool are associated with pediatric asthma hospitalization. This was a retrospective analysis of California hospital discharge data from 2010 to 2012. Children who were hospitalized for asthma-related conditions, were aged 0–14 years, and resided in California were included in analysis. Rates of hospitalization for asthma-related conditions among children residing in California were calculated. Poisson multilevel modeling was used to account for individual- and neighborhood-level risk factors. Every unit increase in the CalEnviroScreen Score was associated with an increase of 1.6% above the mean rate of pediatric asthma hospitalizations (rate ratio (RR) = 1.016, 95% confidence interval (CI) = 1.014–1.018). Every unit increase in racial/ethnic segregation and diesel particulate matter was associated with an increase of 1.1% and 0.2% above the mean rate of pediatric asthma, respectively (RR = 1.011, 95% CI = 1.010–1.013; RR = 1.002, 95% CI = 1.001–1.004). The CalEnviroScreen is a unique tool that combines socioecological factors and environmental indicators to identify vulnerable communities with major health disparities, including pediatric asthma hospital use. Future research should identify mediating factors that contribute to community-level health disparities.

The association between allostatic load and anthropometric measurements among a multiethnic cohort of children

OBJECTIVE

This study investigated if levels of allostatic load (ALoad) differed according to race/ethnicity in children and if ALoad was associated with obesity-related measures.

METHODS

A multiethnic sample of 307 children aged seven to 12 was evaluated, composed of 39% European American (EA), 35% African American (AA), and 26% Hispanic American (HA) youth. Anthropometric measurements were evaluated by dual-energy X-ray absorptiometry, and other measurements included body mass index (BMI) and waist circumference (WC). Allostatic load scores were estimated based on two different calculations, including seven and eight biomarkers (ALoad1 and ALoad2), respectively. Analyses of variance, independence tests, and multiple regression models were performed.

RESULTS

From the total sample, 22.80% (n = 70) of children were characterized as "no load," 46.58% (n = 143) "low load," and 30.62% (n = 94) "high load." Hispanic American children showed the highest ALoad scores (2.07 ± 1.54; 95% CI, 1.73-2.41) compared with AA children (1.71 ± 1.43; 95% CI, 1.43-1.99) and EA children (1.56 ± 1.34; 95% CI, 1.32-1.80) (P < 0.05). Higher scores of ALoad (using both ALoad1 and ALoad2 calculations) were associated with higher BMI, total body fat mass, body percent fat, and WC (P < 0.05).

CONCLUSION

Significant differences in ALoad were observed in children according to race/ethnicity. Increased exposure to stressors captured by ALoad may result in increased risk for excessive adiposity and potential health risk in children. Further, ALoad may serve as a preventive marker for conditions known to continue throughout adulthood.

Transportation noise exposure, noise annoyance and respiratory health in adults: A repeated-measures study

Transportation noise leads to sleep disturbance and to psychological and physiological sustained stress reactions, which could impact respiratory health. However, epidemiologic evidence on associations of objective transportation noise exposure and also perceived noise annoyance with respiratory morbidity is limited. We investigated independent associations of transportation noise exposure and noise annoyance with prevalent respiratory symptoms and incident asthma in adults. Using 17,138 observations (from 7049 participants) from three SAPALDIA (Swiss Cohort Study on Lung and Heart Diseases in Adults) surveys, we assessed associations of transportation noise exposure and noise annoyance with prevalent respiratory symptoms, and with incident asthma (in 10,657 nested observations from 6377 participants). Annual day-evening-night transportation noise comprising road, railway and aircraft Lden (Transportation Lden) was calculated for the most exposed façade of participants' residence using Swiss noise models. Transportation noise annoyance was assessed using an 11-point scale, and participants reported respiratory symptoms and doctor-diagnosed asthma at each survey. We estimated associations with transportation Lden (as well as source-specific Lden) and noise annoyance, independent of air pollution and other potential confounders, using mutually-adjusted mixed logistic and Poisson models and applying random intercepts at the level of the participants. Prevalent respiratory symptoms ranged from 5% (nocturnal dyspnoea) to 23% (regular cough/phlegm). Transportation noise annoyance, but not Lden, was independently associated with respiratory symptoms and current asthma in all participants, with odds ratios (OR) and 95% confidence intervals (CI) ranging between 1.03 (95%CI: 1.01, 1.06) and 1.07 (95% CI: 1.04, 1.11) per 1-point difference in noise annoyance. Both noise annoyance and Lden showed independent associations with asthma symptoms among asthmatics, especially in those reporting adult-onset asthma [OR_Lden: 1.90 (95% CI: 1.25, 2.89) per 10 dB; p-value of interaction (adult-onset vs. childhood-onset): 0.03; OR_{noise annoyance}: 1.06 (95%CI: 0.97, 1.16) per 1-point difference; p-value of interaction: 0.06]. No associations were found with incident asthma. Transportation noise level and annoyance contributed to symptom exacerbation in adult asthma. This suggests both psychological and physiological noise reactions on the respiratory system, and could be relevant for asthma care. More studies are needed to better understand the effects of objective and perceived noise in asthma aetiology and overall respiratory health.

Retrospectively reported childhood adversity is associated with asthma and chronic bronchitis, independent of mental health

Several researchers have raised the concern that the cross-sectional association of retrospectively reported childhood adversity with self-reported onset of asthma and chronic bronchitis in adulthood may be confounded, as well as mediated by an individual's mental health. The aim of this study was to assess the effect of retrospectively reported childhood adversity on self-reported onset of asthma and chronic bronchitis in adulthood, independent of potential confounding and mediating variables (including respondent's mental health). We used data collected in 2007-2008 within the framework of the Tromsø Study (N = 12,981), a representative study of adult men and women in Norway. The associations of childhood adversity with asthma and chronic bronchitis were assessed with Poisson regression models. Relative risks (RR) and 95% confidence intervals (CI) were estimated with bias-corrected bootstrapping. Childhood adversity was associated with a 9% increased risk of asthma (RR = 1.09, 95% CI: 1.02, 1.16) and a 14% increased risk chronic bronchitis (RR = 1.14, 95% CI: 1.03, 1.26) in adulthood, independent of age, sex, parental history of psychiatric problems/asthma/dementia, education, smoking, social support, and respondent's mental health. Controlling for indicators of respondent's mental health reduced the strength of associations of childhood adversity with asthma and chronic bronchitis; however, the associations were still present in the same direction (p < .05). These findings suggest that the association of retrospectively reported childhood adversity with asthma and chronic bronchitis is independent of respondent's mental health. We recommend controlling for indicators of the respondent's mental health to assess an unbiased association of retrospectively measured childhood adversity with self-reported asthma and chronic bronchitis.

New-Onset Asthma and Combat Deployment: Findings From the Millennium Cohort Study

Recent reports suggest US military service members who deployed in support of the recent conflicts in Iraq and Afghanistan have higher rates of new-onset asthma than those who did not deploy. However, it is unknown whether combat experiences, in addition to deployment, contribute to new-onset asthma risk. This study aimed to longitudinally determine the risk factors for developing asthma, including combat deployment (categorized as deployed with combat experience, deployed without combat experience, or nondeployed), among participants in the Millennium Cohort Study from 2001 to 2013. A total of 75,770 participants completed a baseline survey and at least 1 triennial follow-up survey on deployment experiences, lifestyle characteristics, and health outcomes. Complementary log-log models stratified by sex were used to estimate the relative risk of developing asthma among participants who reported no history of asthma at baseline. In models with adjustments, those who deployed with combat experience were 24%-30% more likely to develop asthma than those who did not deploy. Deployed personnel without combat experience were not at a higher risk for new-onset asthma compared with nondeployers. Further research is needed to identify specific features of combat that are associated with greater asthma risk to inform prevention strategies.

Effects of endogenous sex hormones on lung function and symptom control in adolescents with asthma

BACKGROUND

Although pre-puberty asthma is more prevalent in males, after puberty through middle-age, asthma is more prevalent in females. The surge of sex hormones with puberty might explain this gender switch.

METHODS

To examine the effects of sex hormones on lung function and symptoms with puberty, Tanner stage was assessed in 187 children 6-18 years of age (59% severe) enrolled in the NIH/NHLBI Severe Asthma Research Program (SARP). The effects of circulating sex hormones (n = 68; testosterone, dehydroepiandrosterone sulfate (DHEA-S), estrogen, and progesterone) on lung function and 4 week symptom control (ACQ6) in cross-section were tested by linear regression.

RESULTS

From pre-/early to late puberty, lung function did not change significantly but ACQ6 scores improved in males with severe asthma. By contrast females had lower post-BD FEV₁% and FVC% and worse ACQ6 scores with late puberty assessed by breast development. In males log DHEA-S levels, which increased by Tanner stage, associated positively with pre- and post-BD FEV₁%, pre-BD FVC %, and negatively (improved) with ACQ6. Patients treated with high-dose inhaled corticosteroids had similar levels of circulating DHEA-S. In females, estradiol levels increased by Tanner stage, and associated negatively with pre-BD FEV₁% and FVC %.

CONCLUSIONS

These results support beneficial effects of androgens on lung function and symptom control and weak deleterious effects of estradiol on lung function in children with asthma. Longitudinal data are necessary to confirm these cross-sectional findings and to further elucidate hormonal mechanisms informing sex differences in asthma features with puberty.

TRIAL REGISTRATION

ClinicalTrials.gov registration number: NCT01748175 .

Does spending time outdoors reduce stress? A review of real-time stress response to outdoor environments

Everyday environmental conditions impact human health. One mechanism underlying this relationship is the experience of stress. Through systematic review of published literature, we explore how stress has been measured in real-time non-laboratory studies of stress responses to deliberate exposure to outdoor environments. The types of exposures evaluated in this review include: nature viewing, outdoor walks, outdoor exercise and gardening. We characterize study design, modalities of stress measurements, and statistical estimates of effect and significance. Heart rate, blood pressure, and self-report measures provide the most convincing evidence that spending time in outdoor environments, particularly those with green space, may reduce the experience of stress, and ultimately improve health. More work is needed to understand effects of in situ modifications to outdoor environments on residents' stress response.

Association between Allergies and Hypercholesterolemia: A Systematic Review

BACKGROUND

There is controversy in the literature regarding the potential relationship between atopic predisposition (AP) and serum cholesterol levels. To this purpose, we reviewed human studies that investigated this possible link.

METHODS

Following PRISMA guidelines, a literature search of PubMed and Science Direct for peer-reviewed journal articles in English from January 2003, with updates through to August 2016, was conducted. Relevant publications were reviewed that included pediatric and adult populations. Information on the study design, sample, intervention, comparators, outcome, time frame, and risk of bias were abstracted for each article.

RESULTS

Of 601 reviewed reports, 18 were included in this systematic review. Fifteen studies assessed the relationship between AP and serum cholesterol levels. Due to the lack both of observational and cross-sectional studies from the literature search at this time (only 8 studies also analyzed confounding factors) there is a high possibility of confounding variables (familial and genetic predisposition, age, gender, BMI, comorbidity, and medication status) that could not be ruled out.

CONCLUSION

Existing studies are heterogeneous, making it difficult to draw broad conclusions. Future studies and more detailed analyses, considering confounding variables and including a larger and homogeneous population, are needed to strengthen the argument for a link between lipid metabolism and atopy.

Exploring the bio-behavioural link between stress, allostatic load & micronutrient status: A cross-sectional study among adolescent boys

Background & objectives:

Allostatic load (AL) is a cumulative measure of physiological deregulation and is influenced by multiple factors including nutrition. The objectives of the study were to assess AL among adolescent boys (15-19 yr) and delineate its association with psychological stress and micronutrient status.

Methods:

A cross-sectional, school-based study was conducted among 370 adolescent boys of five higher secondary schools from Hyderabad, India. Perceived stress, adolescent life event stress (ALES), psychological morbidity and coping were measured. Biomarkers of AL included dehydroepiandrosterone sulphate, 12-h urinary cortisol, interleukin-6, C-reactive protein, lipid profile, body mass index and blood pressure. Micronutrient status with respect to iron (haemoglobin, ferritin, hepcidin, soluble transferrin receptor), folate, vitamins B12, C and A were analyzed in a sub-sample of 146 boys. AL score ≥3 was calculated from eight biomarkers.

Results:

Fourteen per cent participants had no AL but 34.3 per cent had AL score of ≥ 3. Unadjusted means of ALES scores were significantly different (P = 0.045) among participants with low [mean, 95% confidence interval (CI): 580, 531-629] and high (663, 605-721) AL. After controlling for confounders, the means were significantly different for controllable life event sub-scale of ALES (P = 0.048). Adjusted hepcidin concentrations were significantly higher among participants with high AL (means, 95% CI, 27.2, 24.0-30.8 for high AL; 22.1, 20.2-24.2 μg/l for low AL, P = 0.014).

Interpretation & conclusions:

Build-up of AL was found in adolescent boys and was positively associated with life event stress. Iron nutrition and stress exhibited a positive association through hepcidin. The study provides a link between iron nutrition, physiological deregulation and stress.

Relationships among Maternal Stress and Depression, Type 2 Responses, and Recurrent Wheezing at Age 3 Years in Low-Income Urban Families

RATIONALE

Maternal depression and prenatal and early life stress may influence childhood wheezing illnesses, potentially through effects on immune development.

OBJECTIVES

To test the hypothesis that maternal stress and/or depression during pregnancy and early life are associated with recurrent wheezing and aeroallergen sensitivity and altered cytokine responses (enhanced type 2 or reduced virus-induced cytokine responses) from stimulated peripheral blood mononuclear cells at age 3 years.

METHODS

URECA (Urban Environment and Childhood Asthma) is a birth cohort at high risk for asthma (n = 560) in four inner cities. Maternal stress, depression, and childhood wheezing episodes were assessed by quarterly questionnaires beginning at birth. Logistic and linear regression techniques were used to examine the relation of maternal stress/depression to recurrent wheezing and peripheral blood mononuclear cell cytokine responses at age 3 years.

MEASUREMENTS AND MAIN RESULTS

Overall, 166 (36%) children had recurrent wheeze at age 3 years. Measures of maternal perceived stress at Years 2 and 3 were positively associated with recurrent wheeze (P < 0.05). Maternal depression (any year) was significantly associated with recurrent wheezing (P ≤ 0.01). These associations were also significant when considered in a longitudinal analysis of cumulative stress and depression (P ≤ 0.02). Neither stress nor depression was significantly related to aeroallergen sensitization or antiviral responses. Contrary to our original hypothesis, prenatal and Year 1 stress and depression had significant inverse associations with several type 2 cytokine responses.

CONCLUSIONS

In urban children at high risk for asthma, maternal perceived stress and depression were significantly associated with recurrent wheezing but not increased atopy or reduced antiviral responses.

Associations between postpartum depressive symptoms and childhood asthma diminish with child age

BACKGROUND

Affecting 19% of women, postpartum depression is a major concern to the immediate health of mothers and infants. In the long-term, it has been linked to the development of early-onset asthma at school entry, but only if the depression persists beyond the postnatal period. No studies have tested whether associations with postpartum depressive symptoms and early-onset asthma phenotypes persist into later school age.

OBJECTIVE

To determine associations between maternal postpartum depressive symptoms and childhood asthma between the ages of 5-10 by using a nested longitudinal design.

METHODS

Data were drawn from the 1994-2004 administrations of the Canadian National Longitudinal Survey of Children and Youth, which tracks the health of a nationally representative sample of children in Canada. Child asthma was diagnosed by a health professional, and maternal depressive symptoms were assessed by the Centre for Epidemiological Studies Depression scale. Analyses were conducted by using a multilevel modelling approach, in which longitudinal assessments of asthma in 1696 children were nested within the exposure of postpartum depression.

RESULTS

Postpartum depressive symptoms had a 1.5-fold significant association with childhood asthma between the ages 6-8. This was independent of male sex, maternal asthma, non-immigrant status, low household socioeconomic status, being firstborn, low birthweight, low family functioning and urban-rural residence, of which the first 4 covariates elevated the risk of asthma. Statistical significance was lost at age 8 when maternal prenatal smoking replaced urban-rural residence as a covariate. At ages 9-10, an association was no longer evident.

CONCLUSIONS AND CLINICAL RELEVANCE

Women affected by postpartum depressive symptoms are concerned about long-term health effects of their illness on their infants. Although postpartum depressive symptoms were associated with school-age asthma at ages 6 and 7, this association diminished later. Both home and school life stress should be considered in future studies on asthma development later in childhood.

Adverse childhood experience and asthma onset: a systematic review

Adverse childhood experiences such as abuse and neglect are associated with subsequent immune dysregulation. Some studies show an association between adverse childhood experiences and asthma onset, although significant disparity in results exists in the published literature.

We aimed to review available studies employing a prospective design that investigates associations between adverse childhood experience and asthma. A search protocol was developed and studies were drawn from four electronic journal databases. Studies were selected in accordance with pre-set inclusion criteria and relevant data were extracted.

12 studies, assessing data from a total of 31 524 individuals, were identified that investigate the impact of a range of adverse childhood experiences on the likelihood of developing asthma. Evidence suggests that chronic stress exposure and maternal distress in pregnancy operate synergistically with known triggers such as traffic-related air pollution to increase asthma risk.

Chronic stress in early life is associated with an increased risk of asthma onset. There is evidence that adverse childhood experience increases the impact of traffic-related air pollution and inconsistent evidence that adverse childhood experience has an independent effect on asthma onset.

Maternal depressive symptoms across early childhood and asthma in school children: findings from a Longitudinal Australian Population Based Study

There is a growing body of evidence attesting to links between early life exposure to stress and childhood asthma. However, available evidence is largely based on small, genetically high risk samples. The aim of this study was to explore the associations between the course of maternal depressive symptoms across early childhood and childhood asthma in a nationally representative longitudinal cohort study of Australian children. Participants were 4164 children and their biological mothers from the Longitudinal Study of Australian Children. Latent class analysis identified three trajectories of maternal depressive symptoms across four biennial waves from the first postnatal year to when children were 6–7 years: minimal symptoms (74.6%), sub-clinical symptoms (20.8%), and persistent and increasing high symptoms (4.6%). Logistic regression analyses revealed that childhood asthma at age 6–7 years was associated with persistent and increasing high depressive symptoms after accounting for known risk factors including smoking during pregnancy and maternal history of asthma (adjusted OR 2.36, 95% CI 1.61–3.45), p.001). Our findings from a nationally representative sample of Australian children provide empirical support for a relationship between maternal depressive symptoms across the early childhood period and childhood asthma. The burden of disease from childhood asthma may be reduced by strengthening efforts to promote maternal mental health in the early years of parenting.

Trajectories of depressive symptoms during the transition to young adulthood: the role of chronic illness

BACKGROUND

Little is known about the natural course of depressive symptoms among youth with chronic illness during their transition from adolescence to young adulthood.

METHODS

A representative epidemiological sample of 2825 youth aged 10-11 years from the National Longitudinal Survey of Children and Youth were followed until 24-25 years of age. Presence of chronic illness was measured using self-report and symptoms of depression were assessed using the Center for Epidemiological Studies Depression Scale. Multilevel modeling was used to investigate trajectories of depressive symptoms, adjusting for family environment and sociodemographic characteristics during the transition to young adulthood.

RESULTS

Trajectories showed cubic change over time - increasing from early to mid-adolescence, decreasing to early young adulthood, increasing again to late young adulthood. Youth with chronic illness (n=753) had significantly less favorable trajectories and significantly higher proportions of clinically relevant depressive symptoms over time compared to their peers without chronic illness (n=2072).

LIMITATIONS

This study is limited by selective attrition, self-reported chronic illness and no assessment of illness severity, and mediating effects of family environment factors could not be examined.

CONCLUSIONS

Findings support the diathesis-stress model; chronic illness negatively influenced depressive symptoms trajectories, such that youth with chronic illness had higher depression scores and less favorable trajectories over time. The health and school system are uniquely positioned to support youth with chronic illness navigate this developmental period in an effort to prevent declines in mental health.

Stress and asthma: novel insights on genetic, epigenetic, and immunologic mechanisms

In the United States the economically disadvantaged and some ethnic minorities are often exposed to chronic psychosocial stressors and disproportionately affected by asthma. Current evidence suggests a causal association between chronic psychosocial stress and asthma or asthma morbidity. Recent findings suggest potential mechanisms underlying this association, including changes in the methylation and expression of genes that regulate behavioral, autonomic, neuroendocrine, and immunologic responses to stress. There is also evidence suggesting the existence of susceptibility genes that predispose chronically stressed youth to both post-traumatic stress disorder and asthma. In this review we critically examine published evidence and suggest future directions for research in this field.

Psychological stress and hospitalization for childhood asthma-a nationwide cohort study in two Nordic countries

OBJECTIVE

Exposures to psychological stress in early life may contribute to the development or exacerbation of asthma. We undertook a cohort study based on data from several population-based registers in Denmark and Sweden to examine whether bereavement in childhood led to increased asthma hospitalization.

METHODS

All singleton children born in Denmark during 1977-2008 and in Sweden during 1973-2006 were included in the study (N=5,202,576). The children were followed from birth to the date of first asthma hospitalization, emigration, death, their 18(th) birthday, or the end of study (31 December 2007 in Sweden and 31 December 2008 in Denmark), whichever came first. All the children were assigned to the non-bereaved group until they lost a close relative (mother, father or a sibling), from when they were included in the bereaved group. We evaluated the hazard ratio (HR) of first hospitalization for asthma in bereaved children using Cox proportional hazards regression models, compared to those who were in the non-bereaved group. We also did a sub-analysis on the association between bereavement and first asthma medication.

RESULTS

A total of 147,829 children were hospitalized for asthma. The overall adjusted HR of asthma hospitalization in bereaved children was 1.10 (95% confidence interval (CI): 1.04-1.16), compared to non-bereaved children. The risk of asthma hospitalization was increased in those who lost a close relative at age of 14-17 years (HR=1.54, 95% CI: 1.23-1.92), but not in younger age groups. The association between bereavement and asthma hospitalization did not change over time since bereavement. In the sub-analysis in singleton live births during 1996-2008 recorded in the DMBR, bereavement was associated with a lower use of asthma medication (HR=0.87, 95% CI: 0.80-0.95).

CONCLUSIONS

Our data suggests that psychological stress following bereavement in late adolescence is associated with an increased risk of asthma hospitalization or lowers the threshold for asthma hospitalization.

HIRREM™: a noninvasive, allostatic methodology for relaxation and auto-calibration of neural oscillations

Disturbances of neural oscillation patterns have been reported with many disease states. We introduce methodology for HIRREM™ (high-resolution, relational, resonance-based electroencephalic mirroring), also known as Brainwave Optimization™, a noninvasive technology to facilitate relaxation and auto-calibration of neural oscillations. HIRREM is a precision-guided technology for allostatic therapeutics, intended to help the brain calibrate its own functional set points to optimize fitness. HIRREM technology collects electroencephalic data through two-channel recordings and delivers a series of audible musical tones in near real time. Choices of tone pitch and timing are made by mathematical algorithms, principally informed by the dominant frequency in successive instants of time, to permit resonance between neural oscillatory frequencies and the musical tones. Relaxation of neural oscillations through HIRREM appears to permit auto-calibration toward greater hemispheric symmetry and more optimized proportionation of regional spectral power. To illustrate an application of HIRREM, we present data from a randomized clinical trial of HIRREM as an intervention for insomnia (n = 19). On average, there was reduction of right-dominant temporal lobe high-frequency (23-36 Hz) EEG asymmetry over the course of eight successive HIRREM sessions. There was a trend for correlation between reduction of right temporal lobe dominance and magnitude of insomnia symptom reduction. Disturbances of neural oscillation have implications for both neuropsychiatric health and downstream peripheral (somatic) physiology. The possibility of noninvasive optimization for neural oscillatory set points through HIRREM suggests potentially multitudinous roles for this technology. Research is currently ongoing to further explore its potential applications and mechanisms of action.

Neighborhood disorder and telomeres: connecting children's exposure to community level stress and cellular response

Our objective was to explore the utility of salivary telomere length (sTL) as an early indicator of neighborhood-level social environmental risk during child development. We therefore tested the hypothesis that sTL would be associated with markers of social stress exposure in children. Children age 4-14 from 87 neighborhoods were recruited through five urban schools in New Orleans, Louisiana, U.S. Data were collected at the level of the child, family/household, and neighborhood. DNA was obtained from saliva using commercially available kits and sTL was determined for 104 children using quantitative PCR. Analysis was performed on 99 children who had complete data including sTL, social environmental stress, and additional covariates. The mean sTL value was 7.4 T/S (telomere signal/single-copy signal) ratio units (±2.4, range = 2.5-18.0), and 4.7% of the variance in sTL was attributed to differences across neighborhoods. Children living in neighborhoods characterized by high disorder had an sTL value 3.2 units lower than children not living in high disordered environments (p < 0.05) and their odds of having low relative sTL (defined as <1 standard deviation below standardized Z-score mean) values was 3.43 times that of children not living in high disorder environments (adjusted OR = 3.43, 95% CI = 1.22, 9.62). Our findings are consistent with previous studies in adults demonstrating a strong link between psychosocial stress and sTL obtained from peripheral blood, consistent with previous studies in youth demonstrating an association between early life stress and sTL obtained from buccal cell DNA and offer increased support for the hypothesis that sTL represents a non-invasive biological indicator of psychosocial stress exposure (i.e., neighborhood disorder) able to reflect differences in stress exposure levels even in young children.