BACKGROUND

Air pollution, particularly fine particulate matter (PM_2.5), has been consistently linked to respiratory morbidity, including asthma exacerbations. However, few studies have examined these relationships using statewide zip code–level panels with within-zip identification at a granular zip code level over time.

OBJECTIVE

To assess the association between short-term PM_2.5 exposure and the odds of any pediatric asthma admission from 2006 to 2021 across zip codes, with the goal of identifying patterns of environmental risk for asthma exacerbations.

METHODS

We analyzed zip code–level (zip-day) data from 2006 to 2021, combining hospitalization records for asthma admissions with environmental measures of conventional short-term PM_2.5 exposures, moving averages MA(0–1) and MA(0–3). Zip fixed-effects logistic regression was used to estimate the association between PM_2.5 exposure and the odds of asthma admission, adjusting for day of week, season, flexible calendar time within year, and meteorology (temperature and vapor pressure).

RESULTS

Higher short-term PM_2.5 was associated with higher odds of asthma admission at the zip-day level. Specifically, each +10 μg/m³ increase corresponded to approximately 4% to 5% higher odds (odds ratio ≈ 1.045; 95% CI 1.006–1.085). This relationship was observed under standard moving-average windows after adjustment for meteorological and temporal factors.

CONCLUSIONS

Acute increases in PM_2.5 are associated with a statistically detectable increase in asthma admission odds at the zip code level. Targeted strategies at the zip code level that respond to short-term air quality fluctuations may help reduce asthma-related health burdens.

POLICY IMPLICATIONS

These findings highlight the urgent need for public health interventions and environmental regulations that address short-term increases in air pollution, not just annual averages. Local and state-level policies aimed at monitoring, forecasting, and rapidly mitigating PM_2.5 surges could play a critical role in preventing asthma exacerbations, particularly in urban and vulnerable communities.

Objectives: A fixed combination of long-acting 2-agonists (LABA) plus inhaled corticosteroids

(ICS) has never been proven to reduce asthma exacerbations vs ICS alone in children. This

12-month, double-blind, randomized study in 341 children (age range, 4 to 11 years) with asthma

uncontrolled on ICS investigated whether a novel regimen using budesonide/formoterol for

maintenance and reliever therapy (Symbicort maintenance and relief therapy [SMART]) [Symbicort;

AstraZeneca R&D; Lund, Sweden] could reduce exacerbations.

Methods: Patients received SMART (budesonide/formoterol 80/4.5 g qd maintenance plus

additional inhalations for symptom relief), budesonide/formoterol 80/4.5 g qd for maintenance

(fixed combination), or higher-dose budesonide 320 g qd (fixed-dose budesonide). Blinded

as-needed medication (terbutaline 0.4 g) was provided in both fixed-dose groups.

Results: SMART prolonged the time to first exacerbation vs fixed-dose budesonide (p0.02) and

fixed-dose combination (p<0.001). Rates of exacerbation requiring medical intervention were reduced

by 70 to 79% with SMART vs fixed-dose budesonide and fixed-dose combination (0.08/patient vs

0.28/patient and 0.40/patient, respectively; both p<0.001). Mild exacerbation days and awakenings were

significantly lower with SMART; yearly growth improved by 1.0 cm vs fixed-dose budesonide (p<0.01).

Conclusion: The SMART regimen using budesonide/formoterol for both maintenance and as-needed

symptom relief reduces the exacerbation rate compared with both fixed-dose combination and higher

fixed-dose ICS alone in children with asthma. (CHEST 2006; 130:1733–1743)

Key words: asthma; budesonide/formoterol; inhaled corticosteroids; long-acting 2-agonist; pediatric; Symbicort

Abbreviations: ACTHadrenocorticotrophic hormone; AEadverse events; ANOVAanalysis of variance;EDemergency

department; ICSinhaled corticosteroids; LABAlong-acting 2-agonists; PEFpeak expiratory flow; SMARTSymbicort

maintenance and relief therapy

Bisgaard et. al. (Chest, 2008) Budesonide-Formoterol Maintenance Plus Reliever Therapy, a New Strategy in Pediatric Asthma (1).pdf

Background

Combination inhaled corticosteroid–formoterol reliever monotherapy reduces the rate of asthma attacks compared to short-acting β2-agonist (SABA) reliever monotherapy in adults. Its comparative efficacy in children has not been established.

Methods

CARE was a 52-week, open-label, parallel-group, multicenter, superiority, randomized controlled trial in children aged 5–15 years with asthma using SABA reliever monotherapy at 15 clinical trials sites in New Zealand. Participants were randomly assigned (1:1) to either budesonide 50 μg–formoterol 3 μg, two actuations as needed, or salbutamol 100 μg, two actuations as needed. The primary outcome was asthma attacks as rate per participant per year. This trial was registered with the Australian New Zealand Clinical Trials Registry, ACTRN12620001091998.

Findings

From Jan 28, 2021, to June 23, 2023, we assessed 382 participants for eligibility. We randomly assigned 360 (94%) participants to treatment (179 [50%] to the budesonide–formoterol group and 181 [50%] to the salbutamol group). The annualized rate of asthma attacks was lower in the budesonide–formoterol group than in the salbutamol group—cluster-adjusted rates 0·23 versus 0·41 per participant per year (relative rate 0·55 [95% CI 0·35–0·86]; p=0·012). The number of participants with at least one adverse event was 162 (91%) in the budesonide–formoterol group and 167 (92%) in the salbutamol group (odds ratio 0·79 [95% CI 0·35–1·79]).

Interpretation

In children aged 5–15 years with mild asthma, budesonide–formoterol reliever monotherapy is superior to salbutamol for preventing asthma attacks, with a similar safety profile.

Funding

Health Research Council of New Zealand, Cure Kids New Zealand, and the Barbara Basham Medical Charitable Trust (managed by Perpetual Guardian).

https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(25)00861-X/fulltext

Abstract

This study evaluates how long-term use (i.e., at least one year) of three types of residential ventilation interventions, some of which are coupled with improved central filtration, affects asthma outcomes in adults by reducing exposure to indoor air pollutants. We conducted a quasi-randomized, parallel-group intervention trial involving 51 adults with physician-diagnosed asthma across 40 homes. Each home received one of three interventions: continuous energy recovery ventilators (ERVs), intermittent central-fan-integrated supply (CFIS) systems, or continuous bathroom exhaust fan(s). Homes with ERV or CFIS systems also received central air filtration upgrades to MERV 10 filters, replaced quarterly. Indoor and outdoor air pollutants were measured quarterly. Asthma Control Test (ACT) scores were collected monthly and health-related quality of life and stress were assessed at baseline and endline. Overall, the interventions led to a 6.3 % increase in ACT scores (p < 0.001) over a > 12-month duration, while the increase was 5.4 % when comparing ACT scores within the initial 12-month window following interventions (p < 0.001). The ERV group experienced the greatest improvement, with an 8.4 % increase in ACT scores (p < 0.001) and an increase in the proportion of participants with well-controlled asthma from 50 % to 86 % (p = 0.030). Additionally, the association between reduced indoor pollutant concentrations and asthma outcomes showed that a one standard deviation decrease in indoor NO₂ (IQR: 9.3 ppb) was associated with a 7.1 % increase in ACT scores (p = 0.034). Subgroup analysis indicates that asthma improvements were greater among participants aged ≥45, Black/African American individuals, and those with incomes below $75,000, compared to their respective comparison groups, driven in part by having lower baseline ACT scores.

Abstract

Purpose

The effects of in-home environmental exposures (IHEEs) on asthma are challenging to examine in populations because information on asthma triggers is usually absent. We leveraged data from electronic health records (EHRs) to investigate the associations of residential cockroach and rodent exposures with lung function among children with asthma.

Methods

We merged clinical pulmonary function test data from EHRs for children with asthma from a large safety net hospital in the Northeast United States with publicly available geospatial data matched to patient addresses. Predicted presence of key IHEE asthma triggers, cockroaches and rodents, were included as main exposures and housing parcel features and census tract characteristics were included as potential confounders in a sensitivity analysis. We fit latent Bayesian hierarchical models of percent predicted forced expiratory volume in one second (FEV1%).

Results

The study population of 1070 children had a mean age of 10.2 years and 75 % identified as Black, many living in historically segregated neighborhoods. In models adjusted for individual characteristics, we observed 2.26 (95 % credible interval, 95 %CrI: − 3.72, − 0.79) and 2.58 (95 %CrI: − 4.54, − 0.66) percentage points (pp) lower FEV1% from a one-unit increase in the log-odds of the probability of cockroach and rodent presence, respectively. The association with lung function increased in magnitude for cockroach exposure but attenuated for rodent exposure in sensitivity analyses.

Conclusions

IHEEs were associated with worse lung function among children with asthma in a safety net population. The observed associations underscore how injustices in housing and neighborhood characteristics contribute to asthma morbidity.

Families often struggle to manage their child's asthma. Clinicians caring for children with asthma struggle too as they are tasked with balancing the limited time available in clinic and the need to provide comprehensive care. As a direct consequence, critical gaps in asthma care remain with respect to asthma education and the identification and reduction of environmental asthma triggers in the home. A home visit model that augments clinic-based care is a viable way to fill gaps in understanding, address incomplete adherence patterns, improve disease control by shifting the focus of asthma management to reduction of environmental asthma triggers, and bring cost savings to the health care system.Home Visits, Reduction of Triggers in the Home.pdf

Abstract

Purpose Home Modification and Asthma Triggers.pdf

The study was conducted to investigate the effects of a nursing intervention aimed at home environment modification on symptom control, quality of life, and the number of triggers in children with allergic rhinitis.

Design and methods

This one-to-one, parallel-arm, randomized controlled trial was conducted with a pre-test/post-test design. The study used stratified sampling method. A total of 52 participants were randomly assigned to the intervention group (n = 26) and the control group (n = 26). The intervention group received education on home environment modification and the child was provided with anti-allergic bedding set. The control group continued with routine practices. Statistical significance was set at p < 0.05.

Results

After the nursing intervention for home environment modification, a significant difference was found between the groups in terms of the number of home environment triggers (p < 0.05). According to the mean scores of the Pediatric Rhinoconjunctivitis Quality of Life Questionnaire, no significant difference was found between the groups (p > 0.05). There was no significant difference between the groups in terms of the mean scores for nasal discharge, nasal congestion, sneezing, nasal itching, and eye itching (p > 0.05) after the nursing intervention for home environment modification.

Conclusion

The findings indicate that the nursing intervention for home environment modification is an effective method in reducing the number of triggers in the home environment. However, no significant impact was observed on symptom control and quality of life.

Abstract

Objective

The purposes of this study are to describe and develop preliminary models of the burden of diagnosed asthma and symptoms of possible undiagnosed asthma in a large, citywide, ethnically and socioeconomically diverse sample of Chicago elementary schoolchildren. We hypothesized that considering possible asthma would give a more complete picture of race/ethnic disparities in pediatric asthma.

Methods

We studied 35583 students aged 6 to 12 years attending Chicago Public and Archdiocese elementary schools for the Chicago Initiative to Raise Asthma Health Equity (CHIRAH) study. The full enrollments of 105 schools were surveyed for asthma and possible undiagnosed asthma by the Brief Pediatric Asthma Screen Plus (BPAS+) respiratory symptoms. The child had to be 6 to 12 years old, the valid age range for the BPAS+. Questionnaires included the BPAS+, basic demographic information, and household asthma information; they were sent home with each schoolchild for completion by the parent and returned to school for collection and scoring.

Results

Overall, 13.9% of students had diagnosed asthma. For children aged 6 to 12 years, rates of diagnosed asthma varied from 13.1% to 14.5%, whereas the rates of possible undiagnosed asthma varied from 14.8% to 10.9%. The rate of diagnosed asthma was 21.2% for African Americans, 9.7% for whites, 11.8% for Hispanics, with similar rates of possible undiagnosed asthma. By multinomial logistic regression, African Americans were more than twice as likely and Hispanics were 1.57 times more likely than whites to have diagnosed asthma at all school district income levels and controlling for other household members with asthma, type of school, age of the child, gender, and language preference. The odds of African Americans being diagnosed with asthma rather than having possible asthma were 76% higher and for Hispanics were 46% higher compared with whites, at all school district income levels and controlling for other household members with asthma, type of school, age of the child, gender, and language preference.

Conclusions

Our study confirms national disparities in diagnosed asthma by race/ethnicity. Respiratory symptoms consistent with possible undiagnosed asthma increase the total potential burden of asthma overall to more than one-quarter of the school enrollees. Among students with respiratory symptoms, African Americans, Hispanics (controlling for language), and families where another person has asthma are more likely to have diagnosed rather than possible asthma. Improved knowledge about asthma, recognition of symptoms, and access to high-quality care are necessary to ascertain how much of the possible undiagnosed asthma represents additional cases of asthma requiring treatment.

Up to one-third of patients receiving a clinical diagnosis of COPD or asthma have been shown to lack evidence of disease in subsequent lung-function studies. 

https://cdn-uat.mdedge.com/files/s3fs-public/JFP06803076.PDF

Abstract

Single maintenance and reliever therapy (SMART) is an asthma treatment approach that utilizes combined inhaled corticosteroids and long-acting β-agonists for maintenance and quick relief therapy. Despite the evidence for its benefits in asthma treatment and its adoption into American and international asthma guidelines and recommendations, SMART remains a practice of some debate. This article reviews the available evidence for SMART and offers guidance for its integration into comprehensive asthma management. Overall, short-acting β-agonist-only asthma therapy regimens should be avoided, regardless of condition severity (SOR A Recommendation). Family medicine clinicians should start SMART for patients requiring either GINA Step 3 or 4 therapy, especially if they have signs of poor adherence (SOR B Recommendation). Finally, use budesonide-formoterol over other inhaled corticosteroid/long-acting β-agonist combinations when implementing SMART (SOR B Recommendation).

Keywords: Anti-Asthmatic Agents; Asthma; Evidence-Based Medicine; Pharmacotherapy; Primary Health Care; Single Maintenance and Reliever Therapy (SMART).