Acculturation is associated with asthma burden and pulmonary function in Latino youth: The GALA II study

5-HTP inhibits eosinophilia via intracellular endothelial 5-HTRs; SNPs in 5-HTRs associate with asthmatic lung function

Background

Previous research showed that 5-hydroxytryptophan (5HTP), a metabolic precursor of serotonin, reduces allergic lung inflammation by inhibiting eosinophil migration across endothelial monolayers.

Objective

It is unknown if serotonin receptors are involved in mediating this 5HTP function or if serotonin receptor (HTR) single nucleotide polymorphisms (SNPs) associate with lung function in humans.

Methods

Serotonin receptor subtypes were assessed by qPCR, western blot, confocal microscopy, pharmacological inhibitors and siRNA knockdown. HTR SNPs were assessed in two cohorts.

Results

Pharmacological inhibition or siRNA knockdown of the serotonin receptors HTR1A or HTR1B in endothelial cells abrogated the inhibitory effects of 5HTP on eosinophil transendothelial migration. In contrast, eosinophil transendothelial migration was not inhibited by siRNA knockdown of HTR1A or HTR1B in eosinophils. Surprisingly, these HTRs were intracellular in endothelial cells and an extracellular supplementation with serotonin did not inhibit eosinophil transendothelial migration. This is consistent with the inability of serotonin to cross membranes, the lack of selective serotonin reuptake receptors on endothelial cells, and the studies showing minimal impact of selective serotonin reuptake inhibitors on asthma. To extend our HTR studies to humans with asthma, we examined the CHIRAH and GALA cohorts for HTR SNPs that affect HTR function or are associated with behavior disorders. A polygenic index of SNPs in HTRs was associated with lower lung function in asthmatics.

Conclusions

Serotonin receptors mediate 5HTP inhibition of transendothelial migration and HTR SNPs associate with lower lung function. These results may serve to aid in design of novel interventions for allergic inflammation.

Social Determinants of Health and Allergic Disease Prevalence Among Asian American Children

BACKGROUND

Although racial and ethnic disparities in allergic diseases have previously been observed, the relationship between social determinants of health (SDoH) and allergic disease prevalence among disaggregated Asian American (AsA) subgroups is poorly understood.

OBJECTIVE

To examine the association of SDoH with allergic disease prevalence among disaggregated AsA subgroups.

METHODS

Using the 2011-2018 National Health Interview Survey, we examined caregiver-reported race and ethnicity, SDoH, and allergic diseases. We compared survey-weighted allergic disease prevalence by AsA subgroup. Subgroup-stratified multivariable logistic regression accounting for age, sex, child/parent nativity, and survey year modeled the association between SDoH and allergic disease prevalence. We provide predicted probabilities of having each allergic disease based on exposure to each SDoH.

RESULTS

We examined data from 5042 non-Hispanic AsA children representing 3,264,768 AsA children. Approximately 25% of all AsA children reported at least one allergic disease, ranging from 20% of Asian Indian children to 30% of Filipino/a children. The number of unfavorable SDoH was lowest among Asian Indian and Chinese children (mean 0.7) and highest among "other Asian" children (mean 1.2). In stratified analyses, financial instability and inaccessible healthcare were associated with greater probability of allergic diseases among some, but not all AsA subgroups. Lower parent education level, food insecurity, and rent/other housing arrangement were associated with lower probability of allergic disease among some AsA children.

CONCLUSION

There was heterogeneity in the association of SDoH and allergic disease prevalence among AsA children. Further study of SDoH may inform modifiable environmental factors for allergic disease among AsA children.

The Effect of Obesity on Severity of Asthma: An Observational Prospective Study from Pakistan

Objective

The current research study aimed to access the relationship between obesity and asthma exacerbations and severity among adult patients at the outpatient section of a federal hospital (PIMS) in Islamabad, Pakistan.

Methods

A cross-sectional research study was carried out on 207 asthma adult patients belonging to different areas and ethnic groups from the country. The study setting was the PIMS hospital, which attracts patients from all over the country due to its facilities and cost-effective treatments. The body mass index (BMI) of asthma patients was calculated using the heights and weights of the study subjects. However, the pulmonary functions were calculated using a computerized spirometer i-e Spirolab III S/N 303681 in line with Winspiro PRO 7.1.version software. It presents the patient's forced vital capacity that expires in the first second of expiration to full (FEV1) in comparison to forced vital capacity (FVC) ratio, that is, Tiffeneau-Pinelli index was also recorded to determine the asthma severity.

Results

According to recent surveys, the overall prevalence of patients with overweight and obesity was 29.0% and 23.7%, respectively. A Chi-square test was used, and a statistically significant relationship was observed between BMI and asthma severity (P < 0.001). The adult obese female patients presented poor pulmonary functions. The average FEV1/FVC ratio presented significant variance among four different categories of BMI with P < 0.05. This difference was due to the normal BMI category as the Tiffeneau-Pinelli index, that is, FEV1/FVC in the normal BMI group was significantly lower as compared to that in underweight and obese patients.

Conclusion

The study subjects presented raised asthma severity in accordance with the raised BMI. Obese patients presented comparatively raised asthma exacerbations. Moreover, a statistically significant association of gender difference was observed between obesity and asthma severity. It was concluded that adult asthmatic women with obesity presented raised asthma severity as compared to adult asthmatic males.

Cross-sectional Associations of Multiracial Identity with Self-Reported Asthma and Poor Health Among American Indian and Alaska Native Adults

INTRODUCTION

American Indian and Alaska Native (AI/AN) multiracial subgroups are underrecognized in health outcomes research.

METHODS

We performed a cross-sectional analysis of Behavioral Risk Factor Surveillance System surveys (2013-2019), including adults who self-identified as AI/AN only (single race AI/AN, n = 60,413) or as AI/AN and at least one other race (multiracial AI/AN, (n = 6056)). We used log binomial regression to estimate the survey-weighted prevalence ratios (PR) and 95% confidence intervals (CI) of lifetime asthma, current asthma, and poor self-reported health among multiracial AI/AN adults compared to single race AI/AN adults, adjusting for age, obesity, and smoking status. We then examined whether associations differed by sex and by Latinx identity.

RESULTS

Lifetime asthma, current asthma, and poor health were reported by 25%, 18%, and 30% of multiracial AI/AN adults and 18%, 12%, and 28% single race AI/AN adults. Multiracial AI/AN was associated with a higher prevalence of lifetime (PR 1.30, 95% CI 1.18-1.43) and current asthma (PR 1.36, 95% CI 1.21-1.54), but not poor health. Associations did not differ by sex. The association of multiracial identity with current asthma was stronger among AI/AN adults who identified as Latinx (PR 1.77, 95% CI 1.08-2.94) than non-Latinx AI/AN (PR 1.18, 95% CI 1.04-1.33), p-value for interaction 0.03.

CONCLUSIONS

Multiracial AI/AN adults experience a higher prevalence of lifetime and current asthma compared to single race AI/AN adults. The association between multiracial identity and current asthma is stronger among AI/AN Latinx individuals. The mechanisms for these findings remain under-explored and merit further study.

Structural Racism and the Social Determinants of Health in Asthma

Asthma prevalence and morbidity are disproportionately higher among minoritized communities in the United States. Racial and ethnic disparities in asthma result from complex interactions across biological, environmental, and social factors. Asthma is considered a complex heterogeneous disease consisting of different phenotypes, some of which may be more common in individuals impacted by the downstream effects of structural racism and lack of access to the social determinants of health. Structural racism across generations has created and reinforced inequitable systems through policies and practices which are embedded in the economic, educational, health care, and justice systems (Bailey et al., N Engl J Med 384(8):768-773, 2021; Bailey et al., Lancet 389:1453-1463, 2017; Williams et al., Annu Rev Public Health 40:105-125, 2019). This manifests in an inequitable distribution of resources and the social determinants of health affecting an individual's physical and social environment (Bailey et al., Lancet 389:1453-1463, 2017; Thakur et al., Am J Respir Crit Care Med 202:943-949, 2020; Martinez et al., J Allergy Clin Immunol 148(5):1112-1120, 2021). In this chapter, we outline how inequity in housing, zoning laws, urban planning, education, employment, healthcare access, and healthcare delivery is linked to higher asthma prevalence and morbidity. We also describe the role that chronic physiologic stress has on asthma by enhancing neuroimmune and immunologic responses to environmental exposures. Interventions aimed at addressing the physical or social environment of an individual or community have been shown to improve asthma outcomes in patients at higher risk of severe disease.

Impact of caregiver depression on child asthma outcomes in Mexicans and Puerto Ricans

OBJECTIVE

Examine whether caregiver depressive symptoms at baseline predict longitudinal child asthma outcomes in the two populations with the largest asthma disparities: Mexicans and Puerto Ricans.

METHODS

Two hundred and sixty-seven Hispanic caregiver-child dyads (Mexican = 188, Puerto Rican = 79; children 5-12 years) were recruited from clinics and hospitals in Phoenix, AZ and the Bronx, NY. The Center for Epidemiological Studies Depression Scale assessed caregiver depressive symptoms; higher scores indicate greater depressive symptomology. Medical records verified child asthma diagnosis. Assessments for outcome variables occurred at baseline, 3, 6, 9, and 12-month follow-ups. Pulmonary function was measured by spirometry, asthma control was measured by the Asthma Control Test, steroid bursts and acute healthcare utilization were assessed by caregiver report and medical records, and adherence was measured by doser devices on controller medications. Structural equation modeling analyzed baseline caregiver depressive symptoms as a predictor of longitudinal child asthma outcomes, and differences between subgroups.

RESULTS

Higher caregiver depressive symptoms predicted better pulmonary function (β = .02, p = .001) in Mexican children, and fewer steroid bursts (β = -.41, p = .01) and better medication adherence (β = .02, p = .07) in Puerto Rican children. Caregiver depressive symptoms did not predict pediatric asthma control or acute healthcare utilization in either subgroup.

CONCLUSIONS

Caregiver depressive symptomology had unexpected effects on child asthma outcomes. Results may be explained by the Hispanic paradox, caregiver resilience, acculturation, and the study's longitudinal nature. Further research is needed on social determinants of health that may influence differences in child asthma outcomes in heterogeneous Hispanic communities.

Risk of COPD exacerbation is increased by poor sleep quality and modified by social adversity

STUDY OBJECTIVES

Sleep is an important dimension in the care of chronic obstructive pulmonary disease (COPD), but its relevance to exacerbations is unclear. We wanted to assess whether sleep quality as measured by the Pittsburgh Sleep Quality Index (PSQI) is associated with an increased risk of COPD exacerbations and does this differ by socio-environmental exposures.

METHODS

We included 1647 current and former smokers with spirometrically confirmed COPD from the SPIROMICS cohort. We assessed incidence rate ratios for exacerbation using zero-inflated negative binomial regression adjusting for demographics, medical comorbidities, and multiple metrics of disease severity, including respiratory medications, airflow obstruction, and symptom burden. Our final model adjusted for socio-environmental exposures using the Area Deprivation Index, a composite measure of contemporary neighborhood quality, and Adversity-Opportunity Index, a composite measure of individual-level historic and current socioeconomic indicators. We used a pre-determined threshold of 20% missingness to undertake multiple imputation by chained equations. As sensitivity analyses, we repeated models in those with complete data and after controlling for prior exacerbations. As an exploratory analysis, we considered an interaction between socio-environmental condition and sleep quality.

RESULTS

After adjustment for all co-variates, increasing PSQI scores (range 0-21) were associated with a 5% increased risk for exacerbation per point (p = .001) in the imputed dataset. Sensitivity analyses using complete cases and after controlling for prior exacerbation history were similar. Exploratory analysis suggested less effect among those who lived in poor-quality neighborhoods (p-for-interaction = .035).

CONCLUSIONS

Poor sleep quality may contribute to future exacerbations among patients with COPD. This represents one target for improving disease control.

CLINICAL TRIAL REGISTRATION

Subpopulations and Intermediate Outcome Measures in COPD Study (SPIROMICS). ClinicalTrials.gov Identifier# NCT01969344. Registry URL: https://clinicaltrials.gov/ct2/show/.

Latino-white disparities in ICD-coded asthma diagnosis among US children

INTRODUCTION

It is uncertain if disparities in asthma diagnosis between Latino and non-Hispanic white children stem from differences in diagnosis over time among children presenting with similar clinical scenarios suggestive of asthma.

METHODS

We evaluated the odds of International Classification of Disease (ICD)-coded asthma diagnosis in Latino (English and Spanish preferring) and non-Hispanic white children, overall (N = 524,456) and among those presenting with possible asthma indicators (N = 85,516) over a 13-year period, using electronic health record data from a multi-state network of community health centers.

RESULTS

Among those with possible asthma indicators, Spanish-preferring Latinos had lower adjusted odds of ICD-coded asthma diagnosis compared to non-Hispanic whites (OR = 0.87, 95%CI = 0.77-0.99); English-preferring Latinos did not differ from non-Hispanic whites. Differences in ICD-coded diagnosis between ethnicity/language groups varied by presenting symptom.

CONCLUSIONS

Spanish-preferring Latino children may be less-likely to have ICD-coded asthma documented in the EHR when presenting with certain clinical indicators suggestive of asthma. Clinicians should be cognizant of the need for the follow-up of these indicators in Spanish-preferring Latino children.

Structural racism and its pathways to asthma and atopic dermatitis

Black, Latinx, and Indigenous people in the United States experience a disproportionate burden of asthma and atopic dermatitis. The study of these disease disparities has focused on proximal socioenvironmental exposures and on the biomechanistic (including genetic) differences between racial and ethnic groups. Although biomedical research in allergy and immunology stands to benefit from the inclusion of diverse study populations, the narrow focus on biologic mechanisms disregards the complexity of interactions across biologic and structural factors, including the effects of structural racism. Structural racism is the totality of ways in which society fosters discrimination by creating and reinforcing inequitable systems through intentional policies and practices sanctioned by government and institutions. It is embedded across multiple levels, including the economic, educational, health care, and judicial systems, which are manifested in inequity in the physical and social environment. In this review, we present a conceptual framework and pull from the literature to demonstrate how structural racism is a root cause of atopic disease disparities by way of residential segregation, socioeconomic position, and mass incarceration, which may lead to aberrations in the innate and adaptive immune response and the augmentation of physiologic stress responses, contributing to a disproportionate disease burden for racial and ethnic populations.

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.

Structural and Social Determinants of Health in Asthma in Developed Economies: a Scoping Review of Literature Published Between 2014 and 2019

Purpose of Review

Using the WHO Conceptual Framework for Action on the Social Determinants of Health, this review provides a discussion of recent epidemiologic, mechanistic, and intervention studies of structural and social determinants of health and asthma outcomes covering the period from 2014 to 2019.

Recent Findings

A majority of studies and interventions to date focus on the intermediary determinants of health (e.g., housing), which as the name suggests, exist between the patient and the upstream structural determinants of health (e.g., housing policy). Race/ethnicity remains a profound social driver of asthma disparities with cumulative risk from many overlapping determinants. A growing number of studies on asthma are beginning to elucidate the underlying mechanisms that connect social determinants to human disease. Several effective interventions have been developed, though a need for large-scale policy research and innovation remains.

Summary

Strong evidence supports the key role of the structural determinants, which generate social stratification and inequity, in the development and progression of asthma; yet, interventions in this realm are challenging to develop and therefore infrequent. Proximal, intermediary determinants have provided a natural starting point for interventions, though structural interventions have the most potential for major impact on asthma outcomes. Further research to investigate the interactive effect of multiple determinants, as well as intervention studies, specifically those that are cross-sector and propose innovative strategies to target structural determinants, are needed to address asthma morbidities, and more importantly, close the asthma disparity gap.

Parent Nativity and Child Asthma Control in Families of Mexican Heritage: The Effects of Parent Depression and Social Support

OBJECTIVE

Research has repeatedly demonstrated that parent foreign nativity has a protective effect on child asthma outcomes among Mexican Americans, but the mechanisms underlying this relationship are not well understood. The current study explored parent depression as a mediator and social support as a moderator of the parent nativity-child asthma control pathway.

METHODS

Data come from the baseline sample of a trial (NCT02481986) testing community interventions for 223 children aged 5 to 16 with uncontrolled asthma. We focused on parent/child dyads of Mexican heritage (N = 165; mean age = 9.08, standard deviation = 2.94; 57.3% with Mexico-born parent). Asthma control was defined using the child and adult versions of the Asthma Control Test (ACT). Psychosocial factors included parent depression symptoms and social (instrumental, informational, and emotional) support.

RESULTS

Mexican-born parents had fewer depressive symptoms (β^ = -2.03, SE^ = 0.24) and children with better asthma control (β^ = 1.78, SE^ = 0.24) than US-born parents, P < .0001. Analyses suggested partial mediation of the nativity-ACT path via parent depression (P < .001). An interaction between Instrumental Support and Nativity was marginally significant (β^ = -0.10, SE^ = 0.05, P = .07), with protective effects only observed at higher support levels. Last, among Mexico-born parents, the protective nativity effects on ACT declined with increasing residential years in the United States through 12 years.

CONCLUSIONS

This study is novel in identifying parent depression as one mechanism underlying the effects of parent nativity on child asthma control, but results suggest that the health advantages may depend on availability of support. Providing resources for parent depression and instrumental support (transportation, childcare) can optimize asthma interventions in this population.