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Identification of Asthma Phenotypes in the Spanish MEGA Cohort Study Using Cluster Analysis
Marcos Matabuena1, Francisco Javier Salgado2, Juan José Nieto-Fontarigo3
1Centro Singular de Investigación en Tecnoloxías Intelixentes (CiTIUS), University of Santiago of Compostela, Santiago de Compostela, Spain.
This study identified four distinct asthma phenotypes using cluster analysis. These phenotypes, based on clinical factors, offer a clearer classification for asthma patients.
Area of Science:
- Pulmonology
- Clinical Research
- Data Science
Background:
- Asthma phenotype classification lacks established definitions and consistent cluster study results.
- Unsupervised cluster analysis is needed to identify homogeneous groups representing distinct asthma phenotypes.
- Clinically relevant asthma phenotypes may share common asthma-related outcomes.
Purpose of the Study:
- To develop a classification algorithm for asthma phenotypes.
- To identify distinct clusters representing clinically relevant asthma phenotypes.
- To explore asthma-related outcomes associated with identified phenotypes.
Main Methods:
- A multicenter prospective cohort study (MEGA study) included 512 adult asthma patients.
- Standardized clinical histories were collected for all participants.
- Kernel k-groups algorithm was employed for unsupervised cluster analysis.
Main Results:
- Four distinct asthma clusters were identified.
- Cluster 1: Adult-onset, atopic, good lung function, controlled asthma.
- Cluster 2: Adolescent-onset, atopic, normal lung function, smokers, low adherence.
- Cluster 3: Adult-onset, non-atopic, overweight, severe asthma, combination therapy.
- Cluster 4: Elderly-onset, female, atopic, high BMI, smokers, comorbidities.
Conclusions:
- Four clinically relevant asthma phenotypes were defined using unsupervised cluster analysis.
- These phenotypes are differentiated by FEV1, age of onset, BMI, atopy, severity, control, smoking, and comorbidities.
- This classification advances the understanding of asthma heterogeneity and potential outcome associations.
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