Trends in Asthma Mortality in the United States: 1999 to 2015

Anti-diabetic and anti-inflammatory bioactive hits from Coriaria intermedia Matsum. stem and Dracontomelon dao (Blanco) Merr. & Rolfe bark through bioassay-guided fractionation and liquid chromatography-tandem mass spectrometry

Women have been found to be at a higher risk of morbidity and mortality from type 2 diabetes mellitus (T2DM) and asthma. α-Glucosidase inhibitors have been used to treat T2DM, and arachidonic acid 15-lipoxygenase (ALOX15) inhibitors have been suggested to be used as treatments for asthma and T2DM. Compounds that inhibit both enzymes may be studied as potential treatments for people with both T2DM and asthma. This study aimed to determine potential anti-diabetic and anti-inflammatory bioactive hits from Coriaria intermedia Matsum. stem and Dracontomelon dao (Blanco) Merr. & Rolfe bark. A bioassay-guided fractionation framework was used to generate bioactive fractions from C. intermedia stem and D. dao bark. Subsequently, dereplication through ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) and database searching was performed to putatively identify the components of one bioactive fraction from each plant. Seven compounds were putatively identified from the C. intermedia stem active fraction, and six of these compounds were putatively identified from this plant for the first time. Nine compounds were putatively identified from the D. dao bark active fraction, and seven of these compounds were putatively identified from this plant for the first time. One putative compound from the C. intermedia stem active fraction (corilagin) has been previously reported to have inhibitory activity against both α-glucosidase and 15-lipoxygenase-1. It is suggested that further studies on the potential of corilagin as an anti-diabetic and anti-inflammatory treatment should be pursued based on its several beneficial pharmacological activities and its low reported toxicity.

Secular trends of asthma mortality in China and the United States from 1990 to 2019

BACKGROUND

Asthma imposes a large healthcare burden in China and the United States (US). However, the trends of asthma mortality and the relative risk factors have not been comparatively analyzed between the countries. The aim of this study was to compare the mortality and risk factors between China and the US.

METHODS

The deaths, and mortality rates of asthma in China and the US during 1990-2019 were obtained from the Global Burden of Disease Study 2019. The age-period-cohort model was used to estimate these mortality rates based on a log-linear scale with additive age, period, and cohort effects. The population attributable fractions of risk factors for asthma were estimated.

RESULTS

In 1990-2019, the asthma mortality rate was higher in China than in the US. The crude and age-standardized asthma mortality rates trended downward in both China and the US from 1990 to 2019. The decline in mortality was more obvious in China. Mortality gap between the two countries was narrowing. A sex difference in asthma mortality was observed with higher mortality in males in China and females in the US. The age effects showed that mortality increased with age in adults older than 20 years, particularly in the elderly. Downward trends were generally observed in the period and cohort rate ratios in both countries, with China experiencing a more obvious decrease. Smoking and high body mass index (BMI) were the leading risk factors for asthma mortality in China and the US, respectively. Mortality attributable to occupational asthmagens and smoking decreased the most in China and the US, respectively.

CONCLUSIONS

In 1990-2019, the asthma mortality rate was higher in China than in the US; however, the mortality gap has narrowed. Mortality increased with age in adults. The improvements in asthma death risk with period and birth cohort were more obvious in China than in the US. Smoking, high BMI, and aging are major health problems associated with asthma control. The role of occupational asthmagens in asthma mortality underscores the importance of management and prevention of occupational asthma.

At-home asthma mortality unchanged despite declining mortality in other settings: US death certificate data (2000-2019)

BACKGROUND

Asthma mortality rates in the United States have declined since 1999; however, asthma mortality by place of death has not been comprehensively evaluated.

OBJECTIVE

To evaluate temporal trends in asthma mortality rates and place of death in the United States.

METHODS

We conducted a population-based analysis using data from the Centers for Disease Control and Prevention Wide-ranging ONline Data for Epidemiologic Research platform to evaluate deaths with asthma as the underlying cause (2000-2019) among US residents of all ages. Absolute numbers of asthma-related deaths were described by place of death. Counts were applied to US Census Bureau population counts to calculate mortality rates per 100,000 persons.

RESULTS

In the 20-year period evaluated, 67,695 asthma deaths were registered in the United States. An overall 32% decline in the asthma mortality rate was observed, from 1.43 to 0.98 per 100,000 persons from 2000 to 2019, respectively. Although asthma mortality rates declined in all medical facility locations, the at-home asthma mortality rate remained stable (0.32 and 0.34 per 100,000 persons in 2000 and 2019, respectively). Consequently, the proportion of at-home asthma deaths increased from 23% in 2000 to 2001 to 36% in 2018 to 2019. The distribution of place of death varied by age, sex, race, ethnicity, and geographic region.

CONCLUSION

Despite an overall decline in asthma mortality in the United States, at-home asthma mortality has remained unchanged. In recent years, more than one-third of asthma deaths have occurred at home. These findings warrant further study and underscore the importance of increased efforts to identify and treat uncontrolled asthma across demographic groups.

Serum MMP3 and IL1-RA levels may be useful biomarkers for detecting asthma and chronic obstructive pulmonary disease overlap in patients with asthma

Background

Asthma and chronic obstructive pulmonary disease (COPD) overlap (ACO) is characterized by concurrent features of asthma and COPD. Since disease pathogenesis, severities, and treatments differ between asthma and ACO, it is important to differentiate them.

Objective

To clarify and compare the characteristics of ACO and asthma and identify the serum biomarkers for differentiating them, especially in older patients.

Methods

This study used the data of 639 participants from the nationwide cohort study, the NHOM-Asthma study, an asthma registry in Japan, with complete information on smoking history, respiratory function, and serum biomarkers. ACO was defined as the self-reported comorbidity of COPD or emphysema, or with obstructive pulmonary function and smoking history (pack-years≥10). The clinical characteristics of patients with ACO and asthma without COPD were compared. The serum biomarkers for differentiation were examined using receiver operating characteristic curves and multivariable analysis. The associations between the biomarkers and age were also analyzed.

Results

Of the 639 asthma patients, 125 (19.6%) were diagnosed with ACO; these patients were older and male-dominant and had a higher prevalence of comorbidities such as hypertension, diabetes, and stroke. Among the serum biomarkers that were significantly different between ACO and asthma without COPD, the YKL-40/CHI3L1, MMP3, and IL-1RA levels showed a high area under the curve for discriminating ACO. Only the MMP3 and IL-1RA levels were significantly higher among ACO patients, regardless of age and sex; the YKL-40/CHI3L1 levels were not different due to the effect of age.

Conclusion

MMP3 and IL-1RA may be useful serum biomarkers for distinguishing ACO from asthma.

Machine learning algorithms for predicting determinants of COVID-19 mortality in South Africa

Background

COVID-19 has strained healthcare resources, necessitating efficient prognostication to triage patients effectively. This study quantified COVID-19 risk factors and predicted COVID-19 intensive care unit (ICU) mortality in South Africa based on machine learning algorithms.

Methods

Data for this study were obtained from 392 COVID-19 ICU patients enrolled between 26 March 2020 and 10 February 2021. We used an artificial neural network (ANN) and random forest (RF) to predict mortality among ICU patients and a semi-parametric logistic regression with nine covariates, including a grouping variable based on K-means clustering. Further evaluation of the algorithms was performed using sensitivity, accuracy, specificity, and Cohen's K statistics.

Results

From the semi-parametric logistic regression and ANN variable importance, age, gender, cluster, presence of severe symptoms, being on the ventilator, and comorbidities of asthma significantly contributed to ICU death. In particular, the odds of mortality were six times higher among asthmatic patients than non-asthmatic patients. In univariable and multivariate regression, advanced age, PF1 and 2, FiO2, severe symptoms, asthma, oxygen saturation, and cluster 4 were strongly predictive of mortality. The RF model revealed that intubation status, age, cluster, diabetes, and hypertension were the top five significant predictors of mortality. The ANN performed well with an accuracy of 71%, a precision of 83%, an F1 score of 100%, Matthew's correlation coefficient (MCC) score of 100%, and a recall of 88%. In addition, Cohen's k-value of 0.75 verified the most extreme discriminative power of the ANN. In comparison, the RF model provided a 76% recall, an 87% precision, and a 65% MCC.

Conclusion

Based on the findings, we can conclude that both ANN and RF can predict COVID-19 mortality in the ICU with accuracy. The proposed models accurately predict the prognosis of COVID-19 patients after diagnosis. The models can be used to prioritize COVID-19 patients with a high mortality risk in resource-constrained ICUs.

Predictors of adherence to controller medication in urban African American emerging adults with uncontrolled persistent asthma

BACKGROUND

African American emerging adults tend to have low adherence to asthma controller medication, as well as a disproportionate burden of asthma morbidity and mortality. This study explored constructs from the Information-Motivation-Behavioral Skills model as predictors of controller medication adherence in urban African Americans ages 18-29 (N=152) with uncontrolled asthma using multiple measures of self-reported adherence.

METHODS

Structural equation modeling (SEM) was employed to test the hypothesized mediation model that specified the relationship among psychological distress, substance use, asthma knowledge, motivation, self-efficacy, and adherence.

RESULTS

Results suggested that motivation is an important predictor of adherence to medication; moreover, higher self-efficacy was associated with higher motivation. Results also highlighted psychological distress as an important intervention target to improve medication adherence in emerging adults.

CONCLUSIONS

The model tested in this study may offer a feasible framework for beginning to understand adherence to controller medication in this population.

Trend analysis of asthma mortality and years of life lost from 2004 to 2019 in Southern Iran

Objective

Asthma is a globally important non-communicable disease with major public health consequences. The aim of this study was to determine the mortality rate and years of life lost (YLL) due to asthma in southern Iran.

Methods

All deaths due to asthma in Fars province from the electronic population-based death registration system (EDRS) were obtained. Crude mortality rate, age-standardized mortality rate, YLL and YLL rate data were calculated. The JoinPoint Regression method was used to examine the trend.

Results

During the 16-year study period (2004-2019), 1167 deaths due to asthma occurred in Fars province among which 54.7% (638 cases) were men and 29.6% (346 cases) were in the age group of 70-79 years. Crude mortality rate of asthma had decreased by 121% and 84% in males and females, respectively from 2004 to 2019. The total years of life lost due to asthma during the 16-year study period were 7697 (0.24 per 1000 people) in men, 6882 (0.22 per 1000 people) in women. According to the join point regression analysis, the 16-year trend of YLL rate due to premature mortality was decreasing: the annual percent change (APC) was -5.6% (95% CI -8.2 to -2.9, P = 0.001) for males, -4.4% (95% CI -7.3 to -1.4, P = 0.008) for females.

Conclusion

The trend of mortality and years of life lost due to asthma has decreased significantly during the years of study, although in some age groups, especially the age group of 45-59 years which has the highest number of years of life lost, this trend has been constant and unchanged. It is necessary to conduct other studies to investigate the possible reasons for this unchanged trend in vulnerable age groups.

Differences in Self-Reported Food Allergy and Food-Associated Anaphylaxis by Race and Ethnicity Among SAPPHIRE Cohort Participants

BACKGROUND

Although food allergies are considered common, relatively little is known about disparities in food allergy by race in the United States.

OBJECTIVE

To evaluate differences in reported food allergy and food-associated anaphylaxis among individuals enrolled in a longitudinal cohort study from metropolitan Detroit, Michigan.

METHODS

Participants in the Study of Asthma Phenotypes and Pharmacogenomic Interactions by Race-Ethnicity (SAPPHIRE) were asked about food allergies, including the inciting food and associated symptoms. Individuals were considered to have food-associated anaphylaxis if symptoms coincided with established clinical criteria. Logistic regression was used to assess whether race difference persisted after adjusting for and stratifying by potential confounders. African genetic ancestry was individually estimated among African American SAPPHIRE participants to assess whether ancestry was associated with food allergy.

RESULTS

Within the SAPPHIRE cohort, African American participants were significantly more likely to report food allergy (26.1% vs 17%; P = 3.47 × 10-18) and have food-associated anaphylactic symptoms (12.7% vs 7%; P = 4.65 × 10-14) when compared with European American participants. Allergy to seafood accounted for the largest difference (13.1% vs 4.6%; P = 1.38 × 10-31). Differences in food allergy by race persisted after adjusting for potential confounders including asthma status. Among African American participants, the proportion of African ancestry was not associated with any outcome evaluated.

CONCLUSION

Compared with European Americans, African Americans appear to be at higher risk for developing food allergy and food-associated anaphylaxis, particularly with regard to seafood allergy. The lack of association with genetic ancestry suggests that socioenvironmental determinants may play a role in these disparities.

Epidemiology of Asthma: Prevalence and Burden of Disease

Asthma, a common airway disease, results in a significant burden to both patients and society worldwide. Yet, despite global political commitment backed by the United Nations, progress to reduce the burden of asthma remains inadequate. This is particularly true in low-income countries. To date, progress has been delayed by the lack of uniform data collection, imperfect surveillance methods, inadequate resources, poor access to effective therapies, substandard asthma education, ineffective governmental policies, rapid urbanization, progressive increase in asthma prevalence, increased life expectancy and obesity rates worldwide, asthma heterogeneity and disease complexity, smoking, and environmental exposures to allergens and pollution. A thorough understanding of the challenges facing the international community is essential to define future strategies to improve the burden of asthma.

Comparison of National and Global Asthma Management Guiding Documents

Asthma is a common chronic disease that affects both adults and children, and that continues to have a high economic burden. Asthma management guidelines were first developed nearly 30 years ago to standardize care, maintain asthma control, improve quality of life, maintain normal lung function, prevent exacerbations, and prevent asthma mortality. The two most common asthma guidelines used today were developed by the National Asthma Education and Prevention Program (NAEPP) Expert Panel Working Group and the Global Initiative for Asthma Science Committee. Both guiding documents use scientific methodology to standardize their approach for formulating recommendations based on pertinent literature. Before the 2020 National Asthma Education and Prevention Program (Expert Panel Report 4), nothing had been released since the 2007 guidelines, whereas the Global Initiative for Asthma publishes updates annually. Although each of these asthma strategies is similar, there are some noted differences. Over the years, the focus of asthma treatment has shifted from acute to chronic management. Frontline respiratory therapists and other health-care providers should have a good understanding of these 2 guiding references and how they can impact acute and chronic asthma management. The primary focus of this narrative is to look at the similarities and differences of these 2 guiding documents as they pertain to the 6 key questions identified by the Expert Panel of the National Asthma Education and Prevention Program.

Disparities in Disease Burden and Treatment of Patients Asthma and Chronic Obstructive Pulmonary Disease

Lung health reflects the inequities of our society. Asthma and chronic obstructive pulmonary disease are 2 lung conditions commonly treated in general clinical practice; each imposes a disproportionate burden on disadvantaged patients. Numerous factors mediate disparities in lung health, including air pollution, allergen exposures, tobacco, and respiratory infections. Members of racial/ethnic minorities and those of low socioeconomic status also have inferior access to high-quality medical care, compounding disparities in disease burden. Physicians can work against disparities in their practice, but wide-ranging policy reforms to achieve better air quality, housing, workplace safety, and healthcare for all are needed to achieve equity in lung health.

Historical Redlining Impacts Contemporary Environmental and Asthma-related Outcomes in Black Adults

Rationale: Environmental threats and poorly controlled asthma disproportionately burden Black people. Some have attributed this to socioeconomic or biologic factors; however, racism, specifically historical redlining, a U.S. discriminatory mortgage lending practice in existence between the 1930s and the 1970s, may have actuated and then perpetuated poor asthma-related outcomes. Objectives: To link historical redlining (institutional racism) to contemporary environmental quality- and lung health-related racial inequity. Methods: Leveraging a broadly recruited asthma registry, we geocoded 1,034 registry participants from Pittsburgh/Allegheny County, Pennsylvania, to neighborhoods subjected to historical redlining, as defined by a 1930s Home Owners' Loan Corporation (HOLC) map. Individual-level clinical/physiologic data, residential air pollution, demographics, and socioeconomic factors provided detailed characterization. We determined the prevalence of uncontrolled and/or severe asthma and other asthma-related outcomes by HOLC (neighborhood) grade (A-D). We performed a stratified analysis by self-identified race to assess the distribution of environmental and asthma risk within each HOLC grade. Measurements and Main Results: The registry sampling overall reflected Allegheny County neighborhood populations. The emissions of carbon monoxide, filterable particulate matter <2.5 μm, sulfur dioxide, and volatile organic compounds increased across HOLC grades (all P ⩽ 0.004), with grade D neighborhoods encumbered by the highest levels. The persistent, dispersive socioenvironmental burden peripherally extending from grade D neighborhoods, including racialized access to healthy environments (structural racism), supported a long-term impact of historical/HOLC redlining. The worst asthma-related outcomes, including uncontrolled and/or severe asthma (P < 0.001; Z = 3.81), and evidence for delivery of suboptimal asthma care occurred among registry participants from grade D neighborhoods. Furthermore, elevated exposure to filterable particulate matter <2.5 μm, sulfur dioxide, and volatile organic compound emissions (all P < 0.050) and risk of uncontrolled and/or severe asthma (relative risk [95% confidence interval], 2.30 [1.19, 4.43]; P = 0.009) demonstrated inequitable distributions within grade D neighborhood boundaries, disproportionately burdening Black registry participants. Conclusions: The racist practice of historical/HOLC redlining profoundly contributes to long-term environmental and asthma-related inequities in Black adults. Acknowledging the role racism has in these outcomes should empower more specific and novel interventions targeted at reversing these structural issues.

Prevalence and associations between metabolically unhealthy obesity and asthma exacerbations and emergency department usage

BACKGROUND

Th1 cell polarization and monocyte cell activation influence FEV1/FVC and are affected by body mass index (BMI), insulin resistance, and serum lipoproteins. No study has assessed the impact of metabolic syndrome components on asthma symptom control.

OBJECTIVE

We aimed to determine the prevalence of patients with metabolically unhealthy obesity (MUO) and asthma. Our secondary objective was to compare the strength of associations between asthma outcomes in obese patients measured by BMI, waist circumference, and MUO.

METHODS

A cross-sectional analysis of the combined 2011-2016 cycles of NHANES was performed among persons with asthma. MUO was defined as a BMI ≥ 30kg/m 2 and one of the following: increased waist circumference, insulin resistance, low physical activity, hyperlipidemia, or hypertension. Multiple logistic regression models were computed to assess asthma exacerbations and emergency department usage for asthma in patients with metabolically healthy compared to unhealthy obesity.

RESULTS

Among respondents with MUO, 50.09% (n=543; N=17011880) had asthma compared to 7.91% in those with metabolically healthy obesity (n=77; N=2685858). Persons with MUO were significantly more likely to report the use of an emergency department for their asthma symptoms within the past 12 months (OR 3.53; 95%CI 1.54-8.09). Persons with elevated waist circumference were more likely to report asthma exacerbations (OR 1.58; 95%CI 1.09-2.26). No significant difference existed in reported asthma exacerbations or emergency department usage in patients measured by BMI.

CONCLUSION

Metabolically unhealthy obesity is associated with increased emergency department usage for asthma and is better at predicting exacerbations and emergency department usage than BMI alone.

Asthma and coronavirus disease 2019-related outcomes in hospitalized patients: A single-center experience

BACKGROUND

Several chronic conditions have been associated with a higher risk of severe coronavirus disease 2019 (COVID-19), including asthma. However, there are conflicting conclusions regarding risk of severe disease in this population.

OBJECTIVE

To understand the impact of asthma on COVID-19 outcomes in a cohort of hospitalized patients and whether there is any association between asthma severity and worse outcomes.

METHODS

We identified hospitalized patients with COVID-19 with confirmatory polymerase chain reaction testing with (n = 183) and without asthma (n = 1319) using International Classification of Diseases, Tenth Revision, codes between March 1 and December 30, 2020. We determined asthma maintenance medications, pulmonary function tests, highest historical absolute eosinophil count, and immunoglobulin E. Primary outcomes included death, mechanical ventilation, intensive care unit (ICU) admission, and ICU and hospital length of stay. Analysis was adjusted for demographics, comorbidities, smoking status, and timing of illness in the pandemic.

RESULTS

In unadjusted analyses, we found no difference in our primary outcomes between patients with asthma and patients without asthma. However, in adjusted analyses, patients with asthma were more likely to have mechanical ventilation (odds ratio, 1.58; 95% confidence interval [CI], 1.02-2.44; P = .04), ICU admission (odds ratio, 1.58; 95% CI, 1.09-2.29; P = .02), longer hospital length of stay (risk ratio, 1.30; 95% CI, 1.09-1.55; P < .003), and higher mortality (hazard ratio, 1.53; 95% CI, 1.01-2.33; P = .04) compared with the non-asthma cohort. Inhaled corticosteroid use and eosinophilic phenotype were not associated with considerabledifferences. Interestingly, patients with moderate asthma had worse outcomes whereas patients with severe asthma did not.

CONCLUSION

Asthma was associated with severe COVID-19 after controlling for other factors.

Improving Medication Adherence in Asthma

In little over a generation, the ingenuity of scientists and clinician researchers has developed inhaled medications and pathway-specific biological agents that control the inflammation and physiology of asthma. Unfortunately, whether it is because of cost or difficulty understanding why or how to use inhaled medications, patients often do not take these medications. The consequences of poor treatment adherence, loss of control and exacerbations, are the same as if the condition remained untreated. Furthermore, poor adherence is difficult to detect without direct measurement. Together this means that poor treatment adherence is easily overlooked and, instead of addressing the cause of poor adherence, additional medicines may be prescribed. In other words, poor treatment adherence is a risk for the patient and adds cost to healthcare systems. In this article, we discuss the rationale for and the delivery of successful interventions to improve medication adherence in asthma. We contextualize these interventions by describing the causes of poor treatment adherence and how adherence is assessed. Finally, future perspectives on the design of new interventions are described.

Aerosol inhalation of Mycobacterium bovis can reduce the Th2 dominant immune response induced by ovalbumin sensitization

OBJECTIVE

To investigate whether M. vaccae inhalation affects asthma via γδ T cell regulation.

METHODS

Forty male Balb/c mice were randomly divided into 4 groups: normal group, asthma group, control group and intervention group. The normal group was given no treatment. For the asthma group, control group and intervention group, the mice were sensitized and stimulated with ovalbumin (OVA) to establish asthma models. Mice in the asthma group were not treated. Mice in the control group were treated with γδ T cell suspension from normal mice, and those in the intervention group were treated with γδ T cell suspension from mice intervened by Mycobacterium bovis. ELISA assay was adopted for quantification of IL-4 and IFN-γ in mouse alveolar fluid (BALF), and flow cytometry for determining the percentage of IL-4 and IFN-γ from mononuclear cells of lung tissues.

RESULTS

The airway responsiveness of the asthma group was higher than that of the normal group. The degree of airway inflammation in the intervention group was lighter than that in the control group, and it was significantly alleviated compared with the asthma group (P<0.05). Compared with the asthma group, the level of IL-4 in the BALF of the control group and the intervention group decreased significantly, while the level of IFN-γ increased significantly (P<0.05). Compared with the control group, the level of IL-4 in the BALF of the intervention group was significantly lower, while the level of IFN-γ was significantly higher (P<0.05). In addition, the results of flow cytometry were basically consistent with the results of Elisa.

CONCLUSION

Aerosol inhalation of Mycobacterium bovis can alleviate the Th2 dominant immune response induced by OVA sensitization and regulate the Th1/Th2 immune imbalance in patients with asthma.

Pediatric asthma in developing countries: challenges and future directions

PURPOSE OF REVIEW

Asthma continues to be a significant health problem worldwide, and epidemiological studies in the last few decades have consistently shown a marked increase in childhood asthma prevalence. The International Study of Asthma and Allergies in Childhood (ISAAC) showed significant geographic variability in prevalence, and larger associations with morbidity and mortality in low-middle income countries (LMICs). The Global Burden of Disease estimated that 420,000 deaths occurred globally from asthma in 2016, and although asthma prevalence is higher in high-income countries, most asthma-related mortality occurs in LMICs. The general health of a population is measured, in part, by the under-5 childhood death rate, and developing countries still account for more than 80 percentage of child deaths in the world, highlighting the need for efforts to reduce disease burden in these regions.

RECENT FINDINGS

The burden of asthma is higher in developing countries and underserved populations. Despite this, LMICs still face many barriers to appropriate allergy and asthma care, resulting in significant morbidity, potentially preventable asthma deaths, and economic consequences. A 2017 survey of 112 countries participating in the Global Asthma Network found that only 26 countries (23%) had a national asthma plan for children, with a lower proportion in LMICs.

SUMMARY

The rising asthma prevalence and high asthma-related death rates in LMICs suggest that global efforts in improving asthma diagnosis and care are not reaching the most vulnerable communities. Lack of appropriate diagnosis, availability of viable treatment options, and access to specialised care still remain a challenge in many parts of the world. Though barriers to achieving better outcomes differ in specific populations, many LMICs share similar barriers relating to accessibility.

An Overview of Health Disparities in Asthma

Asthma is a heterogeneous disease characterized by inflammation in the respiratory airways which manifests clinically with wheezing, cough, and episodic periods of chest tightness; if left untreated it can lead to permanent obstruction or death. In the US, asthma affects all ages and genders, and individuals from racial and ethnic minority groups are disproportionately burdened by this disease. The financial cost of asthma exceeds $81 billion every year and despite all the resources invested, asthma is responsible for over 3,500 deaths annually in the nation. In this overview, we highlight important factors associated with health disparities in asthma. While they are complex and overlap, we group these factors in five domains: biological, behavioral, socio-cultural, built environment, and health systems. We review the biological domain in detail, which traditionally has been best studied. We also acknowledge that implicit and explicit racism is an important contributor to asthma disparities and responsible for many of the socio-environmental factors that worsen outcomes in this disease.

Asthma Surveillance - United States, 2006-2018

Problem

Asthma is a chronic disease of the airways that requires ongoing medical management. Socioeconomic and demographic factors as well as health care use might influence health patterns in urban and rural areas. Persons living in rural areas tend to have less access to health care and health resources and worse health outcomes. Characterizing asthma indicators (i.e., prevalence of current asthma, asthma attacks, emergency department and urgent care center [ED/UCC] visits, and asthma-associated deaths) and determining how asthma exacerbations and health care use vary across the United States by geographic area, including differences between urban and rural areas, and by sociodemographic factors can help identify subpopulations at risk for asthma-related complications.

Reporting Period

2006–2018.

Description of System

The National Health Interview Survey (NHIS) is an annual cross-sectional household health survey among the civilian noninstitutionalized population in the United States. NHIS data were used to produce estimates for current asthma and among them, asthma attacks and ED/UCC visits. National Vital Statistics System (NVSS) data were used to estimate asthma deaths. Estimates of current asthma, asthma attacks, ED/UCC visits, and asthma mortality rates are described by demographic characteristics, poverty level (except for deaths), and geographic area for 2016–2018. Trends in asthma indicators by metropolitan statistical area (MSA) category for 2006–2018 were determined. Current asthma and asthma attack prevalence are provided by MSA category and state for 2016–2018. Detailed urban-rural classifications (six levels) were determined by merging 2013 National Center for Health Statistics (NCHS) urban-rural classification data with 2016–2018 NHIS data by county and state variables. All subregional estimates were accessed through the NCHS Research Data Center.

Results

Current asthma was higher among boys aged <18 years, women aged ≥18 years, non-Hispanic Black (Black) persons, non-Hispanic multiple-race (multiple-race) persons, and Puerto Rican persons. Asthma attacks were more prevalent among children, females, and multiple-race persons. ED/UCC visits were more prevalent among children, women aged ≥18 years, and all racial and ethnic groups (i.e., Black, non-Hispanic Asian, multiple race, and Hispanic, including Puerto Rican, Mexican, and other Hispanic) except American Indian and Alaska Native persons compared with non-Hispanic White (White) persons. Asthma deaths were higher among adults, females, and Black persons. All pertinent asthma outcomes were also more prevalent among persons with low family incomes. Current asthma prevalence was higher in the Northeast than in the South and the West, particularly in small MSA areas. The prevalence was also higher in small and medium metropolitan areas than in large central metropolitan areas. The prevalence of asthma attacks differed by MSA category in four states. The prevalence of ED/UCC visits was higher in the South than the Northeast and the Midwest and was also higher in large central metropolitan areas than in micropolitan and noncore areas. The asthma mortality rate was highest in non-MSAs, specifically noncore areas. The asthma mortality rate was also higher in the Northeast, Midwest, and West than in the South. Within large MSAs, asthma deaths were higher in the Northeast and Midwest than the South and West.

Interpretation

Despite some improvements in asthma outcomes over time, the findings from this report indicate that disparities in asthma indicators persist by demographic characteristics, poverty level, and geographic location.

Public Health Action

Disparities in asthma outcomes and health care use in rural and urban populations identified from NHIS and NVSS can aid public health programs in directing resources and interventions to improve asthma outcomes. These data also can be used to develop strategic goals and achieve CDC’s Controlling Childhood Asthma and Reducing Emergencies (CCARE) initiative to reduce childhood asthma hospitalizations and ED visits and prevent 500,000 asthma-related hospitalizations and ED visits by 2024.

Prognostic implications of differences in forced vital capacity in black and white US adults: Findings from NHANES III with long-term mortality follow-up

BACKGROUND

Because Forced Vital Capacity (FVC) is reduced in Black relative to White Americans of the same age, sex, and height, standard lung function prediction equations assign a lower "normal" range for Black patients. The prognostic implications of this race correction are uncertain.

METHODS

We analyzed 5,294 White and 3,743 Black participants age 20-80 in NHANES III, a nationally-representative US survey conducted 1988-94, which we linked to the National Death Index to assess mortality through December 31, 2015. We calculated the FVC-percent predicted among Black and White participants, first applying NHANES III White prediction equations to all persons, and then using standard race-specific prediction equations. We used Cox proportional hazard models to calculate the association between race and all-cause mortality without and with adjustment for FVC (using each FVC metric), smoking, socioeconomic factors, and comorbidities.

FINDINGS

Black participants' age- and sex-adjusted mortality was greater than White participants (HR 1.46; 95%CI:1.29, 1.65). With adjustment for FVC in liters (mean 3.7 L for Black participants, 4.3 L for White participants) or FVC percent-predicted using White equations for everyone, Black race was no longer independently predictive of higher mortality (HR∼1.0). When FVC-percent predicted was "corrected" for race, Black individuals again showed increased mortality hazard. Deaths attributed to chronic respiratory disease were infrequent for both Black and White individuals.

INTERPRETATION

Lower FVC in Black people is associated with elevated risk of all-cause mortality, challenging the standard assumption about race-based normal limits. Black-White disparities in FVC may reflect deleterious social/environmental exposures, not innate differences.

FUNDING

No funding.

Socioeconomic Inequality in Respiratory Health in the US From 1959 to 2018

Importance

Air quality has improved and smoking rates have declined over the past half-century in the US. It is unknown whether such secular improvements, and other policies, have helped close socioeconomic gaps in respiratory health.

Objective

To describe long-term trends in socioeconomic disparities in respiratory disease prevalence, pulmonary symptoms, and pulmonary function.

Design, Setting, and Participants

This repeated cross-sectional analysis of the nationally representative National Health and Nutrition Examination Surveys (NHANES) and predecessor surveys, conducted from 1959 to 2018. included 160 495 participants aged 6 to 74 years.

Exposures

Family income quintile defined using year-specific thresholds; educational attainment.

Main Outcomes and Measures

Trends in socioeconomic disparities in prevalence of current/former smoking among adults aged 25 to 74 years; 3 respiratory symptoms (dyspnea on exertion, cough, and wheezing) among adults aged 40 to 74 years; asthma stratified by age (6-11, 12-17, and 18-74 years); chronic obstructive pulmonary disease ([COPD] adults aged 40-74 years); and 3 measures of pulmonary function (forced expiratory volume in 1 second [FEV1], forced vital capacity [FVC], and FEV1/FVC<0.70) among adults aged 24 to 74 years.

Results

Our sample included 160 495 individuals surveyed between 1959 and 2018: 27 948 children aged 6 to 11 years; 26 956 children aged 12 to 17 years; and 105 591 adults aged 18 to 74 years. Income- and education-based disparities in smoking prevalence widened from 1971 to 2018. Socioeconomic disparities in respiratory symptoms persisted or worsened from 1959 to 2018. For instance, from 1971 to 1975, 44.5% of those in the lowest income quintile reported dyspnea on exertion vs 26.4% of those in the highest quintile, whereas from 2017 to 2018 the corresponding proportions were 48.3% and 27.9%. Disparities in cough and wheezing rose over time. Asthma prevalence rose for all children after 1980, but more sharply among poorer children. Income-based disparities in diagnosed COPD also widened over time, from 4.5 percentage points (age- and sex-adjusted) in 1971 to 11.3 percentage points from 2013 to 2018. Socioeconomic disparities in FEV1 and FVC also increased. For instance, from 1971 to 1975, the age- and height-adjusted FEV1 of men in the lowest income quintile was 203.6 mL lower than men in the highest quintile, a difference that widened to 248.5 mL from 2007 to 2012 (95% CI, -328.0 to -169.0). However, disparities in rates of FEV1/FVC lower than 0.70 changed little.

Conclusions and Relevance

Socioeconomic disparities in pulmonary health persisted and potentially worsened over the past 6 decades, suggesting that the benefits of improved air quality and smoking reductions have not been equally distributed. Socioeconomic position may function as an independent determinant of pulmonary health.

The axis of the receptor for advanced glycation endproducts in asthma and allergic airway disease

Asthma is a generalized term that describes a scope of distinct pathologic phenotypes of variable severity, which share a common complication of reversible airflow obstruction. Asthma is estimated to affect almost 400 million people worldwide, and nearly ten percent of asthmatics have what is considered "severe" disease. The majority of moderate to severe asthmatics present with a "type 2-high" (T2-hi) phenotypic signature, which pathologically is driven by the type 2 cytokines Interleukin-(IL)-4, IL-5, and IL-13. However, "type 2-low" (T2-lo) phenotypic signatures are often associated with more severe, steroid-refractory neutrophilic asthma. A wide range of clinical and experimental studies have found that the receptor for advanced glycation endproducts (RAGE) plays a significant role in the pathogenesis of asthma and allergic airway disease (AAD). Current experimental data indicates that RAGE is a critical mediator of the type 2 inflammatory reactions which drive the development of T2-hi AAD. However, clinical studies demonstrate that increased RAGE ligands and signaling strongly correlate with asthma severity, especially in severe neutrophilic asthma. This review presents an overview of the current understandings of RAGE in asthma pathogenesis, its role as a biomarker of disease, and future implications for mechanistic studies, and potential therapeutic intervention strategies.

Testosterone-to-estradiol ratio and lung function in a prospective study of Puerto Rican youth

BACKGROUND

Age- and sex-related differences in asthma may be due to changes in sex hormone levels.

OBJECTIVE

To evaluate whether a change in free testosterone or free testosterone-to-estradiol ratio is associated with changes in lung function and eosinophils in the Puerto Rican youth.

METHODS

We tested for the association between the change in sex hormone levels and change in lung function or change in eosinophils in a prospective study of 317 children (with and without asthma) followed up from ages 6 to 14 years to ages 10 to 20 years (146 females, 171 males) in San Juan, Puerto Rico. Serum levels of testosterone, estradiol, sex hormone-binding globulin, and progesterone were measured at 2 study visits, approximately 4.9 years apart. Using testosterone and sex hormone-binding globulin levels, we derived free testosterone and the free testosterone-to-estradiol ratio. Multivariable linear regression was used for the analysis of change in lung function and eosinophils, conducted separately by sex.

RESULTS

In girls, each quartile increment in the free testosterone-to-estradiol ratio was associated with a 2.03% increment in percent predicted forced expiratory volume in 1 second (FEV₁)/forced vital capacity (FVC) between study visits. In males, each quartile increment in the free testosterone-to-estradiol ratio was associated with a 3.27% increment in percent predicted FEV₁ and a 1.81% increment in percent predicted FEV₁/FVC between study visits. In girls with asthma, an increased free testosterone-to-estradiol ratio was significantly associated with decreased eosinophils between visits (P=0.03).

CONCLUSION

In Puerto Rican youth, increased free testosterone-to-estradiol ratio over time was associated with an increased FEV₁/FVC in both sexes, and with an increased FEV₁ in males.

Biologic Treatments for Asthma and Chronic Obstructive Pulmonary Disorder

The global COVID-19 pandemic has brought respiratory disease to the forefront of public health, but asthma prevalence has been rising globally for decades. Asthma is mediated by errant immune activation and airway remodeling, but the influences of environment, nutrition, and comorbidities (e.g., asthma-chronic obstructive pulmonary disorder-overlap [ACO]) are still poorly understood. Even as a new generation of biologic-based treatments offer better airway control and reductions in mortality, a lack of prophylactic treatments and mechanistic understanding complicates efforts to prevent pathogenesis. This review will explicate and synthesize current knowledge on the effect of ACO and biologics (omalizumab, mepolizumab, reslizumab, benralizumab, and dupilumab) on pathogenesis, treatment, and prognosis.

Trends in hospital admissions and mortality rates for asthma in Ecuador: a joinpoint regression analysis of data from 2000 to 2018

BACKGROUND

Although asthma has emerged as an important public health problem over recent decades in Latin America, there are limited published data on national hospital admission and mortality rates for asthma from countries in the region.

OBJECTIVE

To analyse trends in asthma hospitalisation and mortality rates in Ecuador over a 19-year period from 2000 to 2018.

METHODS

Hospital discharge and death certificates listing asthma, as defined in the International Classification of Diseases 10th Revision codes (J45 and J46), were used to analyse time trends in rates of hospital admissions and mortality for asthma. The data were obtained from the Ecuadorian National Institute of Statistics and Census. Crude and age-standardised rates were estimated for the entire population. Additionally, specific rates by sex, age and region were estimated. We used joinpoint analysis to identify national trends.

RESULT

During 2000-2018, a total of 58 250 hospitalisations and 1328 deaths due to asthma were identified. The average annual rates for hospitalisation and mortality attributed to asthma were estimated to be 21 (95% CI 19.3 to 22.8) and 5.2 (95% CI 4.4 to 6.0) per 100 000 population, respectively, over this period. Asthma hospital admissions decreased from 28 to 13.7 per 100 000 population between 2000 and 2018, and asthma mortality decreased from 0.8 to 0.3 per 100 000 population over the same period. Based on jointpoint analysis, two temporal trends were identified for hospital admissions. Between 2000 and 2011, hospital admissions decreased 0.8% per year and between 2011 and 2018 decreased 6.6% per year (p<0.05). On average, hospitalisation rates decreased 3.1% per year (p<0.05) over the entire study period. Mortality rate decreased 5.6% per year (p<0.05) over the 19-year period. Hospitalisation rates were higher among females, those aged 5 to 19 years and those living in the Coast region.

CONCLUSIONS

Our analysis shows a temporal trend of reduction in rates of hospitalisations and deaths attributed to asthma between 2000 and 2018 in Ecuador, consistent with similar trends elsewhere in the Latin American region. Health registration systems in Latin America need to be improved to provide reliable data for future between and within country comparisons of trends in asthma hospitalisations and deaths.

National Trends and Disparities in Health Care Access and Coverage Among Adults With Asthma and COPD: 1997-2018

BACKGROUND

Racial and ethnic as well as economic disparities in access to care among persons with asthma and COPD have been described, but long-term access trends are unclear.

RESEARCH QUESTION

Have health coverage and access to care and medications among adults with airways disease improved, and have disparities narrowed?

STUDY DESIGN AND METHODS

Using the 1997 through 2018 National Health Interview Survey, we examined time trends in health coverage and the affordability of medical care and prescription drugs for adults with asthma and COPD, overall and by income and by race and ethnicity. We performed multivariate linear probability regressions comparing coverage and access in 2018 with that in 1997.

RESULTS

Our sample included 76,843 adults with asthma and 30,548 adults with COPD. Among adults with asthma, lack of insurance rose in the first decade of the twenty-first century, peaking with the Great Recession, but fell after implementation of the Affordable Care Act (ACA). From 1997 through 2018, the uninsured rate among adults with asthma decreased from 19.4% to 9.6% (adjusted 9.27 percentage points; 95% CI, 7.1%-11.5%). However, the proportions delaying or foregoing medical care because of cost or going without medications did not improve. Racial and ethnic as well as economic disparities present in 1997 persisted over the study period. Trends and disparities among those with COPD were similar, although the proportion going without needed medications worsened, rising by an adjusted 7.8 percentage points.

INTERPRETATION

Coverage losses among persons with airways disease in the first decade of the twenty-first century were reversed by the ACA, but neither care affordability nor disparities improved. Further reform is needed to close these gaps.

The pharmacoeconomics of the state-of-the-art drug treatments for asthma: a systematic review

Asthma is a chronic disease characterized by significant morbidities and mortality, with a large impact on socio-economic resources and a considerable burden on health-care systems. In the standard care of asthma, inhaled corticosteroids (ICS) associated with long-acting β-adrenoceptor agonists (LABA) are a reliable and often cost-effective choice, especially if based on the single inhaler therapy (SIT) strategy; however, in a subset of patients it is not possible to reach an adequate asthma control. In these cases, it is possible to resort to other pharmacologic options, including corticosteroids (OCS) or biologics. Unfortunately, OCS are associated with important side effects, whilst monoclonal antibodies (mAbs) allow excellent results, even if far more expensive. Up to now, the economic impact of asthma has not been compared with equivalent indicators in several studies. In fact, a significant heterogeneity of the cost analysis is evident in literature, for which the assessment of the real cost-effectiveness of asthma therapies is remarkably complex. To maximize the cost-effectiveness of asthma strategies, especially of biologics, attention must be paid on phenotyping and identification of predictors of response. Several studies were included, involving comparative analysis of drug treatments for asthma, comparative analysis of the costs and consequences of therapies, measurement and evaluation of direct drug costs, and the reduction of health service use. The initial research identified 389 articles, classified by titles and abstracts. A total of 311 articles were excluded as irrelevant and 78 articles were selected. Pharmacoeconomic studies on asthma therapies often report conflicting data also due to heterogeneous indicators and different populations examined. A careful evaluation of the existing literature is extremely important, because the scenario is remarkably complex, with an attempt to homogenize and interpret available data. Based on these studies, the improvement of prescriptive appropriateness and the reduction of the use of healthcare resources thanks to controller medications and to innovative therapies such as biologics partially reduce the economic burden of these treatments. A multidisciplinary stakeholder approach can also be extremely helpful in deciding between the available options and thus optimizing healthcare resources.

Asthma and COVID-19: a systematic review

Background

Severe coronavirus disease-19 (COVID-19) presents with progressive dyspnea, which results from acute lung inflammatory edema leading to hypoxia. As with other infectious diseases that affect the respiratory tract, asthma has been cited as a potential risk factor for severe COVID-19. However, conflicting results have been published over the last few months and the putative association between these two diseases is still unproven.

Methods

Here, we systematically reviewed all reports on COVID-19 published since its emergence in December 2019 to June 30, 2020, looking into the description of asthma as a premorbid condition, which could indicate its potential involvement in disease progression.

Results

We found 372 articles describing the underlying diseases of 161,271 patients diagnosed with COVID-19. Asthma was reported as a premorbid condition in only 2623 patients accounting for 1.6% of all patients.

Conclusions

As the global prevalence of asthma is 4.4%, we conclude that either asthma is not a premorbid condition that contributes to the development of COVID-19 or clinicians and researchers are not accurately describing the premorbidities in COVID-19 patients.

The Role of Extreme Weather and Climate-Related Events on Asthma Outcomes

Extreme weather and climate events are likely to increase in frequency and severity as a consequence of global climate change. These are events that can include flooding rains, prolonged heat waves, drought, wildfires, hurricanes, severe thunderstorms, tornadoes, storm surge, and coastal flooding. It is important to consider these events as they are not merely meteorologic occurrences but are linked to our health. We aim to address how these events are interconnected with asthma outcomes associated with thunderstorm asthma, pollen production, mold infestation from flooding events, and poor air quality during wildfires.

Asthma mortality among Mexican children: Rural and urban comparison and trends, 1999-2016

OBJECTIVE

Although there are more studies showing higher asthma prevalence in urban rather than rural zones, few assessed asthma mortality by zone in children. The objective of this study is to compare asthma mortality rates (AMR) by zone of residence of Mexican children.

DESIGN

Using national death certificate and population projections data, AMR were compared in children aged 0 to 14 years by gender, age group, and zone of residence from 1999 to 2016. AMR trends were calculated using Joinpoint regression.

RESULTS

Of the 680 823 deaths, 2464 (0.36%) were due to asthma. Asthma mortality was higher in rural (0.65%) than urban (0.26%) zones, P < .0001. Whole period AMR median was also higher in rural vs urban zones (0.6 vs 0.3, respectively), P < .05. The average annual percent change (AAPC) of AMR for the whole period was -5.1 in all children with a higher percent decrease in rural vs urban zones (girls' AAPC = -6.3 vs -4.1, respectively and boys' AAPC = -4.8 vs -4.2, respectively). AMR decreased in children aged 0 to 4 from both zones (rural's AAPC: girls = -7.9, boys = -5.2; urban's AAPC: girls = -5.1, boys = -5.4), P < .05. No trend was found in children aged 5 to 14.

CONCLUSIONS

Asthma mortality in Mexican children is higher in rural than urban zones. The decrease of mortality over time in early childhood is reassuring. More research is needed to determine reasons for higher mortality in rural Mexico and for the lack of a favorable decreasing trend in children aged 5 to 14 from both zones.

Multinational cohort study of mortality in patients with asthma and severe asthma

BACKGROUND

Data on the risk of death following an asthma exacerbation are scarce. With this multinational cohort study, we assessed all-cause mortality rates, mortality rates following an exacerbation, and patient characteristics associated with all-cause mortality in asthma.

METHODS

Asthma patients aged ≥18 years and with ≥1 year of follow-up were identified in 5 European electronic databases from the Netherlands, Italy, UK, Denmark and Spain during the study period January 1, 2008-December 31, 2013. Patients with asthma-COPD overlap were excluded. Severe asthma was defined as use of high dose ICS + use of a second controller. Severe asthma exacerbations were defined as emergency department visits, hospitalizations or systemic corticosteroid use, all for reason of asthma.

RESULTS

The cohort consisted of 586,436 asthma patients of which 42,611 patients (7.3%) had severe asthma. The age and sex standardized all-cause mortality rates ranged between databases from 5.2 to 9.5/1000 person-years (PY) in asthma, and between 11.3 and 14.8/1000 PY in severe asthma. The all-cause mortality rate in the first week following a severe asthma exacerbation ranged between 14.1 and 59.9/1000 PY. Mortality rates remained high in the first month following a severe asthma exacerbation and decreased thereafter. Higher age, male gender, comorbidity, smoking, and previous severe asthma exacerbations were associated with mortality.

CONCLUSION

All-cause mortality following a severe exacerbation is high, especially in the first month following the event. Smoking cessation, comorbidity-management and asthma-treatment focusing on the prevention of exacerbations might reduce associated mortality.

Asthma

This review provides an evidence-based guide for the diagnosis, evaluation, and treatment of patients with asthma. It addresses typical questions that arise in the clinic-based care of patients with asthma and provides a basic and comprehensive resource for asthma care.