Related Experiment Video
Updated: May 29, 2025
Advanced Imaging of Lung Homing Human Lymphocytes in an Experimental In Vivo Model of Allergic Inflammation Based on Light-sheet Microscopy
Published on: April 16, 2019
Type 2-high airway inflammation in childhood asthma distinguishes a more severe phenotype
Frederikke R Skov1,2,3, Tamo Sultan1,2,3, Kasper Fischer-Rasmussen1
1COPSAC, Copenhagen Prospective Studies on Asthma in Childhood, Herlev and Gentofte Hospital, University of Copenhagen, Copenhagen, Denmark.
Insights
Childhood asthma phenotyping reveals distinct T2-high and T2-low asthma types. T2-high asthma is linked to persistent disease, higher airway resistance, and increased airway hyperresponsiveness throughout childhood.
Area of Science:
- Pediatric Allergy and Immunology
- Respiratory Medicine
- Clinical Research
Background:
- The clinical distinction between T2-high and T2-low asthma phenotypes in children remains incompletely understood.
- Understanding these differences is crucial for predicting disease trajectories and informing treatment strategies.
Purpose of the Study:
- To investigate the differences in clinical characteristics and lung function between T2-high and T2-low asthma from birth to 18 years of age.
- To analyze long-term lung function trajectories in childhood asthma subtypes.
Main Methods:
- Longitudinal study of 47 children with asthma and 165 controls from the Copenhagen Prospective Studies on Asthma in Childhood cohort.
- Phenotyping of T2-high and T2-low asthma at age 7 based on sensitization, eosinophil counts, and fractional exhaled nitric oxide.
- Comprehensive lung function assessments including plethysmography, spirometry, exercise, cold air, and methacholine challenge tests.
Main Results:
- At age 18, T2-high asthma showed a significantly higher rate of persistent asthma (46.2%) compared to T2-low asthma (9.2%).
- Children with T2-high asthma exhibited persistently higher specific airway resistance and greater lung function reversibility.
- Increased airway hyperresponsiveness to methacholine was observed in the T2-high asthma group.
Conclusions:
- Childhood T2-high asthma is characterized by distinct clinical features, including earlier onset, longer duration, and specific patterns of airway resistance and responsiveness.
- These findings highlight the importance of T2 phenotyping for understanding asthma heterogeneity in children.
- The study provides evidence for different long-term lung function trajectories based on T2 asthma 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.
Related Concept Videos
01:26Asthma-II: Pathophysiology and Classification
Additionally, environmental and genetic factors play crucial roles in determining an individual's susceptibility to asthma and the severity of their condition.
Critical processes in asthma pathophysiology include:
01:20Asthma: Pathogenesis and Management
Asthma is classified as allergic and non-allergic. Allergens such as dust mites, pollen, and pet dander trigger allergic asthma, while factors like cold air, intense emotions, or exercise can induce non-allergic asthma.
01:29Asthma-I: Introduction
01:24Asthma-III: Symptoms and Complications
Classification of Asthma
01:20Chronic Obstructive Pulmonary Disease-II: Pathophysiology
Chronic Inflammation
01:30Asthma-IV: Diagnostic and Management
Clinical Assessment for Asthma:
This is the first step in diagnosing and managing asthma. It includes: