title: Clinical significance of asthma clusters by longitudinal analysis in Korean asthma cohort.
abstract: BACKGROUND
  We have previously identified four distinct groups of asthma patients in KOREAN cohorts using cluster analysis: (A) smoking asthma, (B) severe obstructive asthma, (C) early-onset atopic asthma, and (D) late-onset mild asthma.
  
  
  RESULTS
  A longitudinal analysis of each cluster in a Korean adult asthma cohort was performed to investigate the clinical significance of asthma clusters over 12 months. Cluster A showed relatively high asthma control test (ACT) scores but relatively low FEV1 scores, despite a high percentage of systemic corticosteroid use. Cluster B had the lowest mean FEV1, ACT, and the quality of life questionnaire for adult Korean asthmatics (QLQAKA) scores throughout the year, even though the percentage of systemic corticosteroid use was the highest among the four clusters. Cluster C was ranked second in terms of FEV1, with the second lowest percentage of systemic corticosteroid use, and showed a marked improvement in subjective symptoms over time. Cluster D consistently showed the highest FEV1, the lowest systemic corticosteroid use, and had high ACT and QLQAKA scores.
  
  
  CONCLUSIONS
  Our asthma clusters had clinical significance with consistency among clusters over 12 months. These distinctive phenotypes may be useful in classifying asthma in real practice.
authors.affiliation: Division of Allergy and Clinical Immunology, Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: So Young
authors.initials: SY
authors.lastname: Park
authors.affiliation: Department of Clinical Epidemiology and Biostatistics, Asan Medical Center, Seoul, Korea.
authors.forename: Seunghee
authors.initials: S
authors.lastname: Baek
authors.affiliation: Division of Allergy and Clinical Immunology, Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Sujeong
authors.initials: S
authors.lastname: Kim
authors.affiliation: Division of Allergy and Clinical Immunology, Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Sun-Young
authors.initials: SY
authors.lastname: Yoon
authors.affiliation: Division of Allergy and Clinical Immunology, Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Hyouk-Soo
authors.initials: HS
authors.lastname: Kwon
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Yoon-Seok
authors.initials: YS
authors.lastname: Chang
authors.affiliation: Division of Allergy and Clinical Immunology, Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: You Sook
authors.initials: YS
authors.lastname: Cho
authors.affiliation: Department of Internal Medicine, Soonchunhyang University Bucheon Hospital, Bucheon, Korea.
authors.forename: An-Soo
authors.initials: AS
authors.lastname: Jang
authors.affiliation: Department of Internal Medicine, College of Medicine, Yonsei University, Seoul, Korea.
authors.forename: Jung Won
authors.initials: JW
authors.lastname: Park
authors.affiliation: Department of Internal Medicine, College of Medicine, Ajou University, Suwon, Korea.
authors.forename: Dong-Ho
authors.initials: DH
authors.lastname: Nahm
authors.affiliation: Department of Internal Medicine, College of Medicine, Hanyang University, Seoul, Korea.
authors.forename: Ho-Joo
authors.initials: HJ
authors.lastname: Yoon
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Sang-Heon
authors.initials: SH
authors.lastname: Cho
authors.affiliation: Department of Internal Medicine, College of Medicine, Ewha Womans University, Seoul, Korea.
authors.forename: Young-Joo
authors.initials: YJ
authors.lastname: Cho
authors.affiliation: Department of Internal Medicine, College of Medicine, Chung-Ang University, Seoul, Korea.
authors.forename: ByoungWhui
authors.initials: B
authors.lastname: Choi
authors.affiliation: Division of Allergy and Clinical Immunology, Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Hee-Bom
authors.initials: HB
authors.lastname: Moon
authors.affiliation: Division of Allergy and Clinical Immunology, Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Tae-Bum
authors.initials: TB
authors.lastname: Kim
mesh_terms: D000293:Adolescent; D000305:Adrenal Cortex Hormones / Q000627:therapeutic use; D000328:Adult; D001249:Asthma / Q000145:classification* / Q000188:drug therapy / Q000503:physiopathology*; D016000:Cluster Analysis; D015331:Cohort Studies; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D011788:Quality of Life; D056910:Republic of Korea; D012907:Smoking / Q000009:adverse effects / Q000503:physiopathology; D011795:Surveys and Questionnaires; D055815:Young Adult
chemical_list: D000305:Adrenal Cortex Hormones