Clinical Characteristics of Exacerbation-Prone Adult Asthmatics Identified by Cluster Analysis

• Published in: Allergy, asthma & immunology research Vol. 9; no. 6; pp. 483 - 490
• Main Authors: Kim, Mi-Ae, Shin, Seung-Woo, Park, Jong-Sook, Uh, Soo-Taek, Chang, Hun Soo, Bae, Da-Jeong, Cho, You Sook, Park, Hae-Sim, Yoon, Ho Joo, Choi, Byoung Whui, Kim, Yong Hoon, Park, Choon-Sik
• Format: Journal Article
• Language: English
• Published: Korea (South) The Korean Academy of Asthma, Allergy and Clinical Immunology; The Korean Academy of Pediatric Allergy and Respiratory Disease 01.11.2017; 대한천식알레르기학회
• Subjects: Original; 내과학; cluster analysis; Asthma; exacerbation
• ISSN: 2092-7355; 2092-7363
• DOI: 10.4168/aair.2017.9.6.483

Asthma is a heterogeneous disease characterized by various types of airway inflammation and obstruction. Therefore, it is classified into several subphenotypes, such as early-onset atopic, obese non-eosinophilic, benign, and eosinophilic asthma, using cluster analysis. A number of asthmatics frequently experience exacerbation over a long-term follow-up period, but the exacerbation-prone subphenotype has rarely been evaluated by cluster analysis. This prompted us to identify clusters reflecting asthma exacerbation. A uniform cluster analysis method was applied to 259 adult asthmatics who were regularly followed-up for over 1 year using 12 variables, selected on the basis of their contribution to asthma phenotypes. After clustering, clinical profiles and exacerbation rates during follow-up were compared among the clusters. Four subphenotypes were identified: cluster 1 was comprised of patients with early-onset atopic asthma with preserved lung function, cluster 2 late-onset non-atopic asthma with impaired lung function, cluster 3 early-onset atopic asthma with severely impaired lung function, and cluster 4 late-onset non-atopic asthma with well-preserved lung function. The patients in clusters 2 and 3 were identified as exacerbation-prone asthmatics, showing a higher risk of asthma exacerbation. Two different phenotypes of exacerbation-prone asthma were identified among Korean asthmatics using cluster analysis; both were characterized by impaired lung function, but the age at asthma onset and atopic status were different between the two.