Pulmonary function testing for the diagnosis of asthma in preschool children

Type 2-high airway inflammation in childhood asthma distinguishes a more severe phenotype

BACKGROUND

It remains unclear whether phenotyping of type 2-high (T2-high) asthma can distinguish clinical characteristics and lung function trajectories in childhood.

OBJECTIVE

To explore differences between T2-high and T2-low asthma from birth to age 18 years.

METHODS

We included 47 children with asthma and 165 as a control group from the Copenhagen Prospective Studies on Asthma in Childhood2000 mother-child cohort. T2-high and T2-low asthma was defined at age 7 by sensitization to aeroallergens, elevated eosinophilic blood count, and/or elevated fractional nitric oxide. Lung function measurements included whole-body plethysmography, spirometry, exercise test, cold air provocation, and methacholine challenge. Differences in lung function trajectories and traits were analyzed using linear mixed models, Wilcoxon rank-sum test, Fisher's exact test, and Quasi-Poisson regression.

RESULTS

At age 7 years, 47 had asthma (26 T2-high, 21 T2-low). By age 18, 12 (46.2%) with T2-high had persistent asthma whereas 2 (9.2%) with T2-low; OR 8.14 [1.57-42.34]. Specific airway resistance (sRaw) was 12.5% higher through childhood in children with T2-high asthma (estimate 0.53 [0.06; 1.01]); lung function was more reversible (OR 3.37 [1.03-11.00] for spirometry and OR 2.60 [1.17; 5.75] for sRaw), and they had increased airway hyperresponsiveness (AHR) to methacholine (as shown by 41% lower dose required to cause a 20% drop in lung function (estimate -0.70 [-1.18; -0.23])). There was no significant difference in exacerbation rate and other lung function measurements.

CONCLUSION

Childhood T2-high asthma differs from T2-low asthma in terms of onset, duration, airway resistance, and airway responsiveness.

Effectiveness of specialist nurse-led WeChat mini program management for disease control in asthma: A randomized controlled study

BACKGROUND

Asthma is a common chronic respiratory disease in childhood, requiring effective management strategies.

PURPOSE

This study aims to evaluate the effectiveness of a nurse-led WeChat Mini Program in managing asthma among children aged 6 to 11 years.

METHODS

This randomized controlled trial adhered to the CONSORT checklist and was conducted at a tertiary hospital in China from January 2023 to August 2023. One hundred and eight children with asthma were randomly assigned to two groups, and 81 children completed the 6-month follow-up. All participants received asthma management from specialist nurses, including routine treatments such as inhaled corticosteroids. The experimental group also utilized the WeChat Mini Program for asthma management. Both groups underwent follow-up assessments at 3 and 6 months post-enrollment, which included the Childhood Asthma Control Test (C-ACT), asthma control levels, frequency of exacerbations, and lung function.

RESULTS

At 3 and 6 months, the experimental group showed significantly higher C-ACT scores and a lower exacerbation frequency compared to the control group (p < 0.05). While Peak Expiratory Flow improved, Forced Expiratory Volume in 1 Second Percentage Predicted (FEV1%) and FEV1/FVC did not change significantly.

CONCLUSIONS

The WeChat Mini Program significantly improved asthma control and reduced exacerbations but did not substantially enhance all lung function parameters. Further research is required to confirm its long-term effects.

APPLICATION TO PRACTICE

Incorporating a specialist nurse-led digital management tool, such as the WeChat Mini Program, into standard pediatric asthma care may offer an effective management strategy.

Formulation and evaluation of carrier-based dry powders containing budesonide and arformoterol for inhalation therapy

Asthma and Chronic Obstructive Pulmonary Disease (COPD) are major global health concerns, with inhalation therapy being a primary treatment method. Dry powder inhalers (DPIs) often face challenges related to particle aggregation, which can diminish drug delivery efficiency. This study investigates particle aggregation and aims to optimize the cohesion-adhesion balance to improve inhalation efficiency. Advanced techniques like atomic force microscopy and Raman imaging were used to analyze particle interactions, focusing on lactose ratios, particle morphology, and drug-drug interactions. The therapeutic efficacy of optimized formulations containing budesonide (BUD) and Arformoterol (AFT) was assessed using an asthma model, showing significant improvements in sRAW, neutrophil count, and tidal volume compared to the positive control, with p-values below 0.01. AFT exhibited comparable efficacy to Formoterol at half the dose. Additionally, pharmacokinetic studies demonstrated similar in vivo behavior between the drugs, confirming the therapeutic advantage of AFT, with p-values for AUC0-t and Cmax of .646 and .153, respectively. The fine particle fractions for AFT and BUD were 39.4% and 50.6%, respectively, indicating improved drug delivery efficiency and potential for better clinical outcomes in asthma and COPD patients.

Predictive Value of Impulse Oscillometry Combined with Fractional Expiratory Nitric Oxide Test for Asthma in Preschool Children

Objective

Prediction of asthma in preschool children is challenging and lacks objective indicators. The aim is to observe and analyze the variances between impulse oscillometry (IOS) and fractional expiratory nitric oxide (FeNO) in preschool children with wheezing, establish a joint prediction model, and explore the diagnostic value of combining IOS with FeNO in diagnosing asthma among preschool children.

Patients and methods

This study enrolled children aged 3-6 years with wheezing between June 2021 and June 2022. They were categorized as asthmatic (n=104) or non-asthmatic (n=109) after a 1-year follow-up. Clinical data, along with IOS and FeNO measurements from both groups, underwent univariate regression and multiple regression analyses to identify predictive factors and develop the most accurate model. The prediction model was built using the stepwise (stepAIC) method. The receiver operating characteristic curve (ROC), calibration curve, Hosmer-Lemeshow test, and decision curve analysis (DCA) were employed to validate and assess the model.

Results

During univariate analysis, a history of allergic rhinitis, a history of eczema or atopic dermatitis, and measures including FeNO, R5, X5, R20, Fres, and R5-R20 were found to be associated with asthma diagnosis. Subsequent multivariate analysis revealed elevated FeNO, R5, and X5 as independent risk factors. The stepAIC method selected five factors (history of allergic rhinitis, history of eczema or atopic dermatitis, FeNO, R5, X5) and established a prediction model. The combined model achieved an AUROC of 0.94, with a sensitivity of 0.89 and specificity of 0.88, surpassing that of individual factors. Calibration plots and the HL test confirmed satisfactory accuracy.

Conclusion

This study has developed a prediction model based on five factors, potentially aiding clinicians in early identification of asthma risk among preschool children.

Impulse oscillometry bronchodilator response in preschool children

BACKGROUND

In preschoolers, performing an acceptable spirometry and measuring bronchodilator response (BDR) is challenging; in this context, impulse oscillometry (IOS) represents a valid alternative. However, more studies on the standardization of BDR for IOS in young children are required.

OBJECTIVE

The objective of the study was to identify optimal thresholds to define a positive BDR test with IOS in preschoolers with suspected asthma.

METHODS

Children aged 3-6 years with suspected asthma and their lung function investigated with both IOS and spirometry pre- and post-BDR were retrospectively analyzed. The spirometric BDR was defined as positive when the change of FEV1 was ≥12% or ≥200 mL. The oscillometric BDR was defined as positive in case of change of at least -40% in R5, +50% in X5, and -80% in AX.

RESULTS

Among 72 patients, 36 (age 5.2 ± 1 years; 64% boys) were selected for the subsequent analysis according to ATS/ERS quality criteria of measurements; specifically, 19 patients did not meet IOS and 36 did not meet spirometry criteria. The spirometric BDR was found positive in seven subjects (19.4%); conversely, a positive oscillometric BDR was identified in four patients (11.1%). No patient presented a positive BDR response with both methods. In IOS, the mean decrease in R5 and AX was 19.9% ± 10% and 44% ± 22.1%, and the mean increase in X5 was 23.3% ± 17.8%, respectively. A decrease in R5 of 25.7% (AUC 0.77, p = .03) and an increase in X5 of 25.7% (AUC 0.75, p = .04) showed the best combination of sensitivity and specificity to detect an increase of FEV1 ≥ 12% and/or ≥200 mL.

CONCLUSION

The IOS represents a valid alternative to spirometry to measure BDR in preschool children and should be the gold standard in this age group. We are considering a decrease of 26% in R5 and an increase of 26% in X5 as diagnostic threshold for BDR.

Severe asthma guidelines in children and adolescents: A practical document for physicians

Asthma is a common disease in childhood with a minority of affected children suffering from severe asthma. Patients with severe asthma require high dose inhaled glucocorticoids plus a second controller and/or systemic corticosteroids to be well-controlled or remain uncontrolled despite such treatment. Although only a small subset of children and adolescents falls in this category, the management of affected patients represents a major concern for pediatricians. Guidelines and recommendations have been designed to guide the management of this group of patients. Though the terms "recommendations" and "guidelines" are often used interchangeably, it should be noted that the first one should be used more narrowly to identify specific actions and the second one to broadly refer to the umbrella under which multiple recommendations for a specific condition are provided. Moreover, the availability of several and sometimes-conflicting documents on severe asthma management both in adult and pediatric age could generate confusion among health care professionals. The manuscript analyses seven papers addressing severe asthma, comparing any key aspects and differences. Finally, we tried to create a more practical document for physicians to simplify the interpretation of the several available documents on severe asthma management focusing the pediatric age.

Loss of control in preschoolers with asthma is a risk factor for disease persistency

AIM

To describe the relationship between loss of control events in preschoolers with asthma and persistence of disease.

METHODS

We reviewed medical records of children <6 years diagnosed with asthma in 2018 to assess loss of control events during three years of follow-up. Asthma persistency was defined by redeem of short-acting β2-agonist or asthma controllers within one year after the end of follow-up. Logistic regression models were applied to analyse the association between loss of control events and persistence of asthma.

RESULTS

We included 172 patients (median age 1.8 years), whereof 126 (73.3%) experienced a loss of control event and 87 (50.6%) had asthma one year after the end of follow-up. Any loss of control event was associated with persistence of asthma adjusted for controller treatment at inclusion, prior exacerbations, atopic comorbidity and caesarean section: aOR, 10.9 (95% CI, 3.9-34.6), p < 0.001. This was also significant restricted to events in the first year of follow-up: 3.52 (1.50-8.67), p < 0.01 and among children only experiencing one event: 6.4 (1.7-27.3), p = 0.01.

CONCLUSION

Loss of control events during a 3-year period among preschoolers with asthma are closely related to disease persistency, which may aid clinicians to assess risk of persistent asthma in young children.