Epidemiology of asthma in the United States

Physical comorbidity is associated with overnight hospitalization in U.S. adults with asthma: an assessment of the 2005-2018 National Health and Nutrition Examination Surveys

OBJECTIVE

Identifying the effects of comorbidity on healthcare utilization is critical for understanding the benefits of improved comorbidity management. Asthma is a common respiratory condition, associated with gastrointestinal, metabolic, psychiatric, and other respiratory conditions. Adults with asthma represent a key population in understanding comorbidity and its consequences. The objective was to explore the relationship between comorbidity and overnight hospitalizations in U.S. adults with asthma.

STUDY DESIGN AND METHODS

A cross-sectional sample of 3,887 subjects aged 20-79 was aggregated from seven cycles (2005-2018) of the National Health and Nutrition Examination Survey (NHANES). The survey design was created using the full seven cycles, then a subpopulation was used for the analysis. Design-based modified Poisson regression with robust standard errors compared the prevalence of overnight hospitalizations in subjects with and without comorbidities. Comorbidity was defined as the presence of one or more additional chronic conditions.

RESULTS

Over half (61.6%) of patients with asthma reported having comorbidities. The overnight hospitalization prevalence was higher in those with comorbidities (21.6%) than those without (7.4%). The adjusted prevalence ratio of overnight hospitalizations in those with comorbidities vs. those without was 2.02 (95% CI: 1.54-2.66). Conclusions from sensitivity analyses remained the same.

CONCLUSIONS

Comorbidity in U.S. adult asthma patients is associated with increased overnight hospitalizations. Study results concur with examinations of other healthcare utilization outcomes, revealing how comorbidity influences healthcare utilization patterns in patients with asthma. The reduction of overnight hospitalizations should be a targeted goal when developing and evaluating interventions to manage comorbidities in patients with asthma.

Scoping review: multiple stakeholders and child asthma management interventions

OBJECTIVE

This study reviewed research to identify interventions aimed at improving asthma management among children by educating parents and other professionals.

DATA SOURCES

PubMed, Medline, and Embase databases were utilized.

STUDY SELECTIONS

Three databases were searched for child asthma management interventions published between 2012-2022 in English. Search terms included children, asthma, intervention(s), community pediatrics, coaches, schools, and stakeholders. Inclusion criteria were being an experimental study focused on children with asthma (birth-18 years), including stakeholder involvement, education, and a community focus. The search yielded 153 articles; nine were reviewed.

RESULTS

In general, stakeholders developed programs that resulted in improvements in asthma symptoms, knowledge of asthma management, perceptions of health care, and decreased emergency health care visits. Successful interventions involved education about asthma management, providing medications, and partnerships with school staff, healthcare teams, and community members. Effective coordination and communication contributed to successful program implementation. Using technology for asthma management education was effective in tracking access to care and facilitated the delivery of medications.

CONCLUSION

The findings indicate that interventions were effective in improving child asthma management. Stakeholder partnerships were critical to the effectiveness of interventions. Marketing the intervention and encouraging communication with parents also fostered success. Being able to assess the home environment and staying in contact with parents were barriers to these interventions. Conducting randomized controlled trials using the interventions found effective in these studies to assess change in symptoms and emergency care visits over time would yield important information about their long-term success and cost for implementation.

Use of the PAQLQ Questionnaire and Spirometry to Assess the Control of Asthma in Adolescents

The objective: was to investigate the level of asthma control in adolescents using the PAQLQ questionnaire and spirometry. Materials and methods. The study included 60 adolescents aged 12 to 18 years, patients with asthma, without clinical and functional signs of exacerbation. 43.4% of adolescents (26 people) had a controlled course, and 56.6% of children (34 people) had a partially controlled asthma. Results. According to the results of bronchodilation tests 3 times more often showed a positive response when using a combined bronchodilator, compared with salbutamol (χ2y=4.37; p=0,04). The average increase in FEV1 was 1,4 times greater in children after the use of ipratropium bromide / fenoterol – 8,9±0,8%, compared with the results of the test using salbutamol – 6,2±0,6% (p<0,05). After evaluating the results of spirometry, the proportion of children with incomplete asthma control was 63,3%. Detected 38,5% of patients with a total QOL PAQLQ <6 points in controlled asthma. After conducting a survey on the PAQLQ questionnaire and spirometric examination, the percentage of children with incomplete control of asthma increased 1,6 times from 43,3% to 73,3% (χ2=11,1; p<0,05). Conclusion. Clinical monitoring is not always sufficient to properly assess the level of asthma control in adolescents. Consideration of several assessment methods makes it possible to more accurately determine the level of asthma control in a patient.

Spatiotemporal variations of asthma admission rates and their relationship with environmental factors in Guangxi, China

OBJECTIVE

The study aimed to determine if and how environmental factors correlated with asthma admission rates in geographically different parts of Guangxi province in China.

SETTING

Guangxi, China.

PARTICIPANTS

This study was done among 7804 asthma patients.

PRIMARY AND SECONDARY OUTCOME MEASURES

Spearman correlation coefficient was used to estimate correlation between environmental factors and asthma hospitalisation rates in multiple regions. Generalised additive model (GAM) with Poisson regression was used to estimate effects of environmental factors on asthma hospitalisation rates in 14 regions of Guangxi.

RESULTS

The strongest effect of carbon monoxide (CO) was found on lag1 in Hechi, and every 10 µg/m3 increase of CO caused an increase of 25.6% in asthma hospitalisation rate (RR 1.26, 95% CI 1.02 to 1.55). According to the correlation analysis, asthma hospitalisations were related to the daily temperature, daily range of temperature, CO, nitrogen dioxide (NO2) and particulate matter (PM2.5) in multiple regions. According to the result of GAM, the adjusted R2 was high in Beihai and Nanning, with values of 0.29 and 0.21, which means that environmental factors are powerful in explaining changes of asthma hospitalisation rates in Beihai and Nanning.

CONCLUSION

Asthma hospitalisation rate was significantly and more strongly associated with CO than with NO2, SO2 or PM2.5 in Guangxi. The risk factors of asthma exacerbations were not consistent in different regions, indicating that targeted measures should differ between regions.

Prevalence and determinants of current asthma in Cameroon

INTRODUCTION

The prevalence of asthma varies from one country to another due to differences in ethnicity, socio-economics status, environmental and climatic risk factors. The aim of this study was to determine the prevalence and determinants of current asthma in Cameroonian adults.

MATERIAL AND METHODS

Data from 4 cross-sectional community-based studies from 2014 to 2018 were analyzed. Participants aged 19 years and above were selected through multilevel stratified random sampling methods across 2 urban areas, 2 semi-urban areas and 1 rural area. Current asthma was defined as "wheezing in the last 12 months in a subject with self-reported asthma or having used drugs for asthma treatment". Logistic regression was used to investigate the determinants of current asthma.

RESULTS

A total of 10,707 adults [median age (interquartile range)=36 (26-52) years, 44.5% of men] were definitively enrolled in the study. The overall prevalence [95% confidence interval (CI)] of current asthma was 3.9% (3.5-4.3)%. Determinants [odd's ratio (OR), (95%CI)] of current asthma were: Sudanese ethnicity [1.9(1.4-2.7)], rural area [1.5(1.1-2.1)], urban area [1.6(1.2-2.2)], past history of pneumonia [1.9(1.1-3.4)], allergic rhino-conjunctivitis [6.5(4.7-8.9)], atopic eczema [2.3(1.5-3.6)], body mass index (BMI)≥40kg/m² [1.9(1.0-3.4)] and BMI<18kg/m² [1.8(1.2-2.9)].

CONCLUSION

The prevalence of current asthma is close to the low value of the Sub-Saharan African range. Sudanese ethnicity, rural area, urban area, history of pneumonia, allergic disease, severe obesity and underweight were determinants of current asthma in Cameroon. More research is surely warranted to understand the mechanisms underlying the association of asthma with Sudanese ethnicity.

Hotspot detection and socio-ecological factor analysis of asthma hospitalization rate in Guangxi, China

BACKGROUND

Asthma is a major public health concern throughout the world. Numerous researches have shown that the spatial-temporal patterns of asthma are inconsistent, leading to the suggestion that these patterns are determined by multiple factors. This study aims to detect spatial-temporal clusters of asthma and analyze socio-ecological factors associated with the asthma hospitalization rate in Guangxi, China.

METHODS

Asthma hospitalization and socio-ecological data for 88 counties/municipal districts in Guangxi, China in 2015 was collected. Space-time scan statistics were applied to identify the high-risk periods and areas of asthma hospital admissions. We further used GeoDetector and Spearman correlation coefficient to investigate the socio-ecological factors associated with the asthma hospitalization rates.

RESULTS

There were a total of 7804 asthma admissions in 2015. The high-risk period was from April to June. The age groups of 0-4 and ≥65 years were both at the highest risk, with hospital admission rates of 45.0/10⁵ and 46.5/10⁵, respectively. High-risk areas were found in central and western Guangxi with relative risk (RR) values of asthma hospitalizations greater than 2.0. GDP per capita and altitude were positively associated with asthma hospitalizations, while air pressure and wind speed had a negative association. The explanatory powers of these factors (i.e., GDP per capita, altitude, air pressure, wind speed) were 22%, 20%, 14% and 10%, respectively.

CONCLUSIONS

The GDP per capita appears to have the strongest correlation with asthma hospitalization rates. High-risk areas were identified in central and western Guangxi characterized by high GDP per capita. These findings may be helpful for authorities developing targeted asthma prevention policies for high-risk areas and vulnerable populations, especially during high-risk periods.

MicroRNA-145 down-regulates mucin 5AC to alleviate airway remodeling and targets EGFR to inhibit cytokine expression

This study aims to explore how microRNA-145 (miR-145) affects airway remodeling and cytokine expression by targeting epidermal growth factor receptor (EGFR) to regulate mucin 5AC (MUC5AC).Mice alveolar epithelial cells (AECs) were divided into a control, blank, miR-145 mimics, mimic control, miR-145 inhibitors, inhibitor control, si-EGFR and miR-145 inhibitors + si-EGFR group. Asthma mice models with airway remodeling were induced with an Ovalbumin (OVA) solution and randomly divided into a normal, asthma, asthma + miR-145 mimics, asthma + miR-145 mimic control, asthma + si-EGFR or asthma + si-EGFR NC group. Airway remodeling degree and histomorphology was measured using hematoxylin-eosin (HE), Masson and periodic acid-Schiff (PAS) staining. Flow cytometry was used to detect Th2 and Th17 cells in peripheral blood, ELISA was used to measure inflammatory factors. qRT-PCR and western blotting was adapted to detect the expressions of EGFR and the relevant cytokines that are regulated by miR-145.The control, miR-145 mimics and si-EGFR groups showed a higher expression of miR-145 and a lower expression of EGFR and cytokines than the blank, mimic control, inhibitor control and miR-145 inhibitor + si-EGFR groups. Mice in the asthma + miR-145 mimics and asthma + si-EGFR groups showed lower WAt/Pbm, WAi/Pbm and WAm/Pbm, less inflammatory cells, less airway modeling and alleviated goblet cell hyperplasia and mucus obstruction than the asthma group. Furthermore, the expressions of EGFR and cytokines of transfected cells and lung tissues were negatively related to those of miR-145. MiR-145 can down-regulate MUC5AC by negatively targeting EGFR and thereby relieving airway remodeling.

Blocking Allergic Reaction through Targeting Surface-Bound IgE with Low-Affinity Anti-IgE Antibodies

Allergic disorders have now become a major worldwide public health issue, but the effective treatment options remain limited. We report a novel approach to block allergic reactivity by targeting the surface-bound IgE of the allergic effector cells via low-affinity anti-human IgE Abs with dissociation constants in the 10^-6 to 10^-8 M range. We demonstrated that these low-affinity anti-IgE mAbs bind to the cell surface-bound IgE without triggering anaphylactic degranulation even at high concentration, albeit they would weakly upregulate CD203c expression on basophils. This is in contrast to the high-affinity anti-IgE mAbs that trigger anaphylactic degranulation at low concentration. Instead, the low-affinity anti-IgE mAbs profoundly block human peanut- and cat-allergic IgE-mediated basophil CD63 induction indicative of anaphylactic degranulation; suppress peanut-, cat-, and dansyl-specific IgE-mediated passive cutaneous anaphylaxis; and attenuate dansyl IgE-mediated systemic anaphylaxis in human FcεRIα transgenic mouse model. Mechanistic studies reveal that the ability of allergic reaction blockade by the low-affinity anti-IgE mAbs was correlated with their capacity to downregulate the surface IgE and FcεRI level on human basophils and the human FcεRIα transgenic mouse bone marrow-derived mast cells via driving internalization of the IgE/FcεRI complex. Our studies demonstrate that targeting surface-bound IgE with low-affinity anti-IgE Abs is capable of suppressing allergic reactivity while displaying an excellent safety profile, indicating that use of low-affinity anti-IgE mAbs holds promise as a novel therapeutic approach for IgE-mediated allergic diseases.

A systematic review and meta-analysis of complementary and alternative medicine in asthma

Asthma is a chronic, inflammatory lung disease affecting around 235 million people worldwide. Conventional medications in asthma are not curative and patients have significant concerns regarding their side-effects. Consequently, many asthma patients turn to complementary and alternative medicine (CAM) for a more holistic approach to care. We systematically reviewed the available evidence on the effectiveness of CAM in the management of asthma in adults.We searched the MEDLINE, EMBASE, CINAHL, AMED and Cochrane databases for randomised controlled trials published in English between 1990 and 2016 investigating the effectiveness of oral or topical CAM in asthmatic adults. The quality of the studies was assessed using the Cochrane Risk of Bias Assessment Tool.In all, 23 eligible trials were identified covering 19 different CAMs. Overall, there was limited evidence on the effectiveness of CAM in adult asthma as most CAMs were only assessed in a single trial. CAMs with multiple trials provided null or inconsistent results. Many of the trials were rated as having high risk of bias.The existing evidence is insufficient to recommend any of the oral and topical CAMs in the management of asthma in adults.

Biomimetic Cross-Reactive Sensor Arrays: Prospects in Biodiagnostics

Biomimetic cross-reactive sensor arrays have been used to detect and analyze a wide variety of vapour and liquid components in applications such as food science, public health and safety, and diagnostics. As technology has advanced over the past three decades, these systems have become selective, sensitive, and affordable. Currently, the need for non-invasive and accurate devices for early disease diagnosis remains a challenge. This review provides an overview of the various types of Biomimetic cross-reactive sensor arrays (also referred to as electronic noses and tongues in the literature), their current use and future directions, and an outlook for future technological development.

Characterization and redox mechanism of asthma in the elderly

Asthma is a chronic disease characterized by reversible airflow limitation, coughing, bronchial constriction, and an inflammatory immune response. While asthma has frequently been categorized as emerging in childhood, evidence has begun to reveal that the elderly population is certainly susceptible to late-onset, or even long-standing asthma. Non-atopic asthma, most commonly found in elderly patients is associated with elevated levels of serum and sputum neutrophils and may be more detrimental than atopic asthma. The mortality of asthma is high in the elderly since these patients often possess more severe symptoms than younger populations. The redox mechanisms that mediate inflammatory reactions during asthma have not been thoroughly interpreted in the context of aging. Thus, we review the asthmatic symptoms related to reactive oxygen species (ROS) and reactive nitrogen species (RNS) in seniors. Moreover, immune status in the elderly is weakened in part by immunosenescence, which is broadly defined as the decline in functionality of the immune system that corresponds with increasing age. The effects of immunosenescence on the expression of biomarkers potentially utilized in the clinical diagnosis of asthma remain unclear. It has also been shown that existing asthma treatments are less effective in the elderly. Thus, it is necessary that clinicians approach the diagnosis and treatment of asthmatic senior patients using innovative methods. Asthma in the elderly demands more intentional diagnostic and therapeutic research since it is potentially one of the few causes of mortality and morbidity in the elderly that is largely reversible.

Asthma phenotypes and endotypes: a personalized approach to treatment

PURPOSE OF REVIEW

Asthma is quite common and is better described as a syndrome with a heterogeneous presentation than as a single disease. Although most individuals can be effectively managed using a guideline-directed approach to care, those with the most severe illness may benefit from a more targeted therapy. The review describes our current understanding of how asthma phenotypes (observable characteristics) and endotypes (specific biologic mechanisms) can be employed to gain insight into asthma pathobiology and personalized therapy.

RECENT FINDINGS

Our understanding of the heterogeneity of asthma is increasing. The concept of asthma phenotype has become more complex, incorporating both clinical and biologic features. Several asthma endotypes (e.g., allergic bronchopulmonary mycosis, aspirin-exacerbated respiratory disease, severe late-onset hypereosinophilic asthma, etc.) have been proposed, but further research is needed to delineate specific mechanisms underlying asthma pathogenesis. Several biologic therapies targeting certain phenotypes are in development and are expected to broaden our armamentarium for treatment of severe asthma.

SUMMARY

Asthma is a heterogeneous condition with diverse characteristics and biologic mechanisms. Severe asthma is associated with significant morbidity and even mortality and represents a major unmet need. Stratification of asthma subtypes into phenotypes and endotypes should move the field forward in terms of more effective and personalized treatment.

Review: Immunology of sinusitis, trauma, asthma, and sepsis

Background:

This review article is important for allergists/immunologists and otolaryngologists. It discussed chronic rhinosinusitis, epidemiology, pathogenesis, innate adaptive immunology, nuclear factor–kappa B related to inflammation, sepsis, complement, reactive oxygen species, asthma, sinusitis, elderly pathogenesis, oxidative stress, depression, seasonal variation, vitamin D, genetic susceptibility and sepsis, hereditary angioedema related to trauma and stress.

Objective:

The objective of this review is to link chronic rhinosinusitis, epidemiology, innate and adaptive immunology, NF-kappa B related to inflammation, sepsis, complement, reactive oxygen species, asthma and sinusitis.

Methods:

A literature search was conducted from several articles, prospective studies, recent reviews and earlier reports. A synergistic relationship develops between activation of the innate immune system and the loss of organ barrier functions. Many complex factors, such as genetics, physical agents, mediators in the development of organ failure both in asthma, sinusitis, stress, depression and trauma, leading to posttraumatic organ failure. Asthma and sepsis, a common condition encountered in hospital environments remains an important cause of death at intensive care units where allergists/immunologists and otolaryngologists are frequently consulted. The patient's immune surveillance could fail to eliminate the pathogen, allowing it to spread and there is a proinflammatory mediator release with inappropriate activation.

Conclusion:

This review discussed chronic rhinosinusitis, sinusitis related to trauma, the innate and adaptive immunology, NF-kappa B related to inflammation, sepsis, complement, inflammation, reactive oxygen species, asthma pathogenesis, and asthma in the elderly, oxidative stress, depression, seasonal variation and vitamin D, cytokines, genetic susceptibility related to sepsis, hereditary angioedema related to trauma and stress.

Parents and adolescents preferences for asthma control: a best-worst scaling choice experiment using an orthogonal main effects design

Background

The preferences of parents and children with asthma influence their ability to manage a child’s asthma and achieve good control. Potential differences between parents and adolescents with respect to specific parameters of asthma control are not considered in clinical asthma guidelines. The objective was to measure and compare the preferences of parents and adolescents with asthma with regard to asthma control parameters using best worst scaling (BWS).

Methods

Fifty-two parents of children with asthma and 44 adolescents with asthma participated in a BWS study to quantify preferences regarding night-time symptoms, wheezing/chest tightening, changes in asthma medications, emergency visits and physical activity limitations. Conditional logit regression was used to determine each group’s utility for each level of each asthma control parameter.

Results

Parents displayed the strongest positive preference for the absence of night-time symptoms (β = 2.09, p < 0.00001) and the strongest negative preference for 10 emergency room visits per year (β = −2.15, p < 0.00001). Adolescents displayed the strongest positive preference for the absence of physical activity limitations (β = 2.17, p < 0.00001) and the strongest negative preference for ten physical activity limitations per month (β = −1.97). Both groups were least concerned with changes to medications.

Conclusion

Parents and adolescents placed different weights on the importance of asthma control parameters and each group displayed unique preferences. Understanding the relative importance placed on each parameter by parents and adolescents is essential for designing effective patient-focused disease management plans.

Electronic supplementary material

The online version of this article (doi:10.1186/s12890-015-0141-9) contains supplementary material, which is available to authorized users.

CD8+ T Cells Mediate Female-Dominant IL-4 Production and Airway Inflammation in Allergic Asthma

The prevalence and severity of bronchial asthma are higher in females than in males after puberty. Although antigen-specific CD8+ T cells play an important role in the development of asthma through their suppressive effect on cytokine production, the contribution of CD8+ T cells to sex differences in asthmatic responses remains unclear. In the present study, we investigated the sex-specific effect of CD8+ T cells in the suppression of asthma using an ovalbumin mouse model of asthma. The number of inflammatory cells in bronchoalveolar lavage (BAL) fluid, lung type 2 T-helper cytokine levels, and interleukin-4 (IL-4) production by bronchial lymph node cells were significantly higher in female wild-type (WT) mice compared with male mice, whereas no such sex differences were observed between male and female cd8α-disrupted mice. The adaptive transfer of male, but not female, CD8+ T cells reduced the number of inflammatory cells in the recovered BAL fluid of male recipient mice, while no such sex difference in the suppressive activity of CD8+ T cells was observed in female recipient mice. Male CD8+ T cells produced higher levels of IFN-γ than female CD8+ T cells did, and this trend was associated with reduced IL-4 production by male, but not female, CD4+ T cells. Interestingly, IFN-γ receptor expression on CD4+ T cells was significantly lower in female mice than in male mice. These results suggest that female-dominant asthmatic responses are orchestrated by the reduced production of IFN-γ by CD8+ T cells and the lower expression of IFN-γ receptor on CD4+ T cells in females compared with males.

Enhancing Asthma Self-Management in Rural School-Aged Children: A Randomized Controlled Trial

PURPOSE

To test the effects of 2 modes of delivering an asthma educational intervention on health outcomes and asthma self-management in school-aged children who live in rural areas.

METHODS

Longitudinal design with data collected 4 times over 12 months. The target sample was composed of children in grades 2-5 who had a provider diagnosis of asthma. Elementary schools were stratified into high or low socioeconomic status based on student enrollment in the free or reduced-cost lunch program. Schools were then randomly assigned to 1 of 3 treatment arms: in-school asthma class, asthma day camp, or the attention-control group.

FINDINGS

Sample retention was good (87.7%) and equally distributed by study arm. Improvements in emergency department visits and office visits were related to attending either the asthma class or asthma day camp. Asthma severity significantly decreased in both asthma treatment groups. Other factors such as hospitalizations, parent asthma management, and child asthma management improved for all groups.

CONCLUSIONS

Both asthma class and asthma day camp yielded significant reductions in asthma severity. There were reductions in the emergency department and office visits for the 2 asthma arms, and hospitalizations declined significantly for all groups. Asthma self-management also improved in all groups, while it was somewhat higher in the asthma arms. This may be due to the attention being drawn to asthma management by study participation and the action of completing questionnaires about asthma management, asthma symptoms, and health outcomes.

The acute management of asthma

Patients presenting to the emergency department (ED) or clinic with acute exacerbation of asthma (AEA) can be very challenging varying in both severity and response to therapy. High-dose, frequent or continuous nebulized short-acting beta2 agonist (SABA) therapy that can be combined with a short-acting muscarinic antagonist (SAMA) is the backbone of treatment. When patients do not rapidly clinically respond to SABA/SAMA inhalation, the early use of oral or parenteral corticosteroids should be considered and has been shown to impact the immediate need for ICU admission or even the need for hospital admission. Adjunctive therapies such as the use of intravenous magnesium and helium/oxygen combination gas for inhalation and for driving a nebulizer to deliver a SABA and or SAMA should be considered and are best used early in the treatment plan if they are likely to impact the patients' clinical course. The use of other agents such as theophylline, leukotriene modifiers, inhaled corticosteroids, long-acting beta2 agonist, and long-acting muscarinic antagonist currently does not play a major role in the immediate treatment of AEA in the clinic or the ED but is an important therapeutic option for physicians to be aware of and to consider initiating at the time of discharge from clinic, hospital, or ED to reduce later clinical worsening and readmission to the ED and hospital. A comprehensive summary is provided of the currently available respiratory pharmaceuticals approved for asthma and other airway syndromes. Clinicians must be prepared to use the entire spectrum of medications available for the treatment of acute asthma exacerbations and the agents that should be initiated to prevent worsening or additional exacerbations. They need to be familiar with the major potential drug toxicities associated with their use.

Asthma control and cognitive function in a cohort of elderly adults

OBJECTIVES

To determine whether poor asthma control is associated with cognitive impairment in a cohort of older, inner-city adults with asthma.

DESIGN

Prospective observational cohort study.

SETTING

Outpatient practices in New York City and Chicago.

PARTICIPANTS

Individuals aged 60 and older with a physician diagnosis of asthma and without chronic obstructive pulmonary disease or a smoking history of 10 pack-years or more (N = 452).

MEASUREMENTS

Cognitive assessments that included processing speed (pattern comparison, Trail-Making Test Part A), executive function (Trail-Making Test Part B), attention and working memory (letter number sequencing), immediate and delayed recall (Wechsler Memory Scale Story A), word fluency (animal naming), and global cognitive function (Mini-Mental State Examination) were administered. Asthma control was measured using the Asthma Control Questionnaire (ACQ) and airway obstruction using spirometry as the predicted forced expiratory volume at 1 second (FEV1) of less than 70%. Cognitive measures were modeled in linear and logistic regression models controlling for age, race, education, English proficiency, and income.

RESULTS

Participants had a mean age of 68; 41% had poor asthma control according to the ACQ, and 35% had FEV1 of less than 70%. Poor asthma control and FEV1 less than 70% were significantly associated with all measures of cognitive function in univariate analyses, although these associations lost their statistical significance after adjusting for age, education, English proficiency, and other covariates. The same pattern was observed when the outcomes were below-normal performance on the cognitive measures based on normative data.

CONCLUSION

Poor asthma control and airway obstruction are not associated with poor performance on various measures of cognitive function in older adults with asthma.

Gestational age-specific associations between infantile acute bronchiolitis and asthma after age five

BACKGROUND

Infantile acute bronchiolitis (AB) is a risk factor for the development of paediatric asthma. The associations might differ according to gestational age.

METHODS

Data sets of emergency department (ED) visits (January 2002 to June 2010) and livebirth records (January 2002 to December 2004) from the state of Georgia were linked for all children who survived 1 year. Exposure was an ED visit for AB during infancy, and the outcome was an ED visit for asthma after age 5 years. The risk of asthma among children with AB (n = 11 564) was compared with the risk of asthma among children who did not have an ED visit for AB but who utilised the ED for another reason during infancy (n = 131 694). Associations were estimated using log-binomial regression models that controlled for several plausible confounders. Effect measure modification of the risk ratio by gestational age was investigated.

RESULTS

Unadjusted asthma risks (per 100 children) through June 2010 were 4.5 for children with AB and 2.3 for children without AB. The adjusted risk ratio for the overall association was 1.9 [95% confidence interval 1.7, 2.1]. We did not observe effect modification of the risk ratio by gestational age.

CONCLUSION

A positive association was observed between ED visits for AB and subsequent asthma ED visits after age 5; associations did not vary meaningfully by gestational age. Sensitivity analyses did not suggest large biases due to differences in ED utilisation across sociodemographic groups or loss to follow-up from residential migration.

Quantifying preferences for asthma control in parents and adolescents using best-worst scaling

BACKGROUND

Understanding the views of parents and children is critical to designing effective asthma management programs. It was hypothesized that parents and adolescents would exhibit heterogenous preferences with regard to asthma control.

METHODS

Fifty parents of children with asthma and 51 adolescents with asthma participated in a best-worst scaling study to quantify preferences regarding night-time symptoms, wheezing/chest tightening, changes in asthma medications, emergency visits and physical activity limitations.

RESULTS

A latent class analysis revealed heterogeneity inherent in the preferences of parents and adolescents. Two classes of parents emerged from the analysis that displayed significantly different preferences. The first displayed strong preferences for averting night-time symptoms, wheezing/chest tightening, physical activity limitations and emergency room visits with odds ratios (OR) of 42 (95% CI 24, 72), 40 (95% CI 23, 68), 26 (95% CI 15, 44) and 21 (95% CI 12, 35), respectively, compared to an OR of 1 for 10 physical activity limitations per month. A second smaller parent class displayed more balanced preferences. Most adolescents displayed similar preferences for averting night-time symptoms, wheezing/chest tightening, physical activity limitations and emergency room visits, with ORs of 28 (95% CI 16, 48), 25 (95% CI 14, 44), 27 (95% CI 15, 46) and 20 (95% CI 11, 34) respectively.

CONCLUSIONS

This study revealed the importance placed on averting night-time symptoms, wheezing and chest tightening, emergency room visits and physical activity limitations by parents and adolescents alike, with greater emphasis on symptom aversion by parents. Preference heterogeneity exists and should be considered in customized asthma management programs.

Blocking KV1.3 channels inhibits Th2 lymphocyte function and treats a rat model of asthma

Allergic asthma is a chronic inflammatory disease of the airways. Of the different lower airway-infiltrating immune cells that participate in asthma, T lymphocytes that produce Th2 cytokines play important roles in pathogenesis. These T cells are mainly fully differentiated CCR7(-) effector memory T (TEM) cells. Targeting TEM cells without affecting CCR7(+) naïve and central memory (TCM) cells has the potential of treating TEM-mediated diseases, such as asthma, without inducing generalized immunosuppression. The voltage-gated KV1.3 potassium channel is a target for preferential inhibition of TEM cells. Here, we investigated the effects of ShK-186, a selective KV1.3 channel blocker, for the treatment of asthma. A significant proportion of T lymphocytes in the lower airways of subjects with asthma expressed high levels of KV1.3 channels. ShK-186 inhibited the allergen-induced activation of peripheral blood T cells from those subjects. Immunization of F344 rats against ovalbumin followed by intranasal challenges with ovalbumin induced airway hyper-reactivity, which was reduced by the administration of ShK-186. ShK-186 also reduced total immune infiltrates in the bronchoalveolar lavage and number of infiltrating lymphocytes, eosinophils, and neutrophils assessed by differential counts. Rats with the ovalbumin-induced model of asthma had elevated levels of the Th2 cytokines IL-4, IL-5, and IL-13 measured by ELISA in their bronchoalveolar lavage fluids. ShK-186 administration reduced levels of IL-4 and IL-5 and induced an increase in the production of IL-10. Finally, ShK-186 inhibited the proliferation of lung-infiltrating ovalbumin-specific T cells. Our results suggest that KV1.3 channels represent effective targets for the treatment of allergic asthma.

Evaluating the effect of an asthma self-management intervention for rural families

OBJECTIVE

To present outcomes of an asthma self-management educational intervention delivered to children (grades 2-5) at school and to parents in a home visit.

METHODS

The intervention effectiveness was tested in a 12-month longitudinal study with randomization by elementary schools into treatment and attention-control groups with 183 children who had a diagnosis of asthma. Data were collected at four time points. Change over time was examined with linear mixed models.

RESULTS

Quality of life (QOL), hospitalizations, and emergency department visits improved significantly for all the children. African American and Mexican American children had worse asthma-related QOL than did White children. Asthma management behaviors, asthma self-efficacy, and coping likewise improved with girls improving significantly more than the boys. Significant improvements in inhaler skill and asthma severity were seen in the treatment group children when compared to the control group. Treatment group parents showed significant improvements in home asthma management and self-efficacy.

CONCLUSIONS

The improvement in inhaler skill is an important finding for practitioners as this is a behavior that can be addressed in the clinical setting. The reduction in the treatment group's asthma severity scores may reflect the improvement in medication delivery as their inhaler skill improved. The differential improvement between boys and girls points to the need for testing other formats in asthma education that can address different learning styles. The individualized parent asthma education enabled the intervener to incorporate neighborhood and home environmental information thereby allowing for tailoring of parental instruction.