Sputum eosinophilia, airway hyperresponsiveness and airway narrowing in young adults with former asthma.
BACKGROUND
30-80% of outgrown asthma subjects develop symptoms again later in life. We investigated inflammation and function of lower airway in adolescents with former asthma.


METHODS
326 never-smoking young adults (mean age 24.0 years) were interviewed with special emphasis on history of asthma. Diagnosis of asthma was based on GINA guidelines. Former asthma subjects consisted of ones with a history of physician-diagnosed childhood asthma, who had been free of asthma symptoms without the use of medication for at least 10 years prior to the study. Provocative concentration of methacholine causing a 20% fall in forced expiratory volume in 1 second (FEV(1))(PC(20)) and eosinophil percentage in induced sputum were measured.


RESULTS
31 subjects were former asthma subjects (FBA), 11 subjects were current asthma subjects (CBA) and 284 subjects had no history of asthma (non-BA). PC(20) and FEV(1)/FVC ratio were significantly lower in the FBA group than in the non-BA group (P < 0.01). Maximal mid-expiratory flow (MMF) was significantly lower in the FBA group than in the non-BA group (P < 0.05). Sputum eosinophil percentage was significantly increased in the FBA group compared with the non-BA group (P < 0.01). PC(20) was significantly lower in the CBA group than in the FBA and non-BA groups (P < 0.01). FEV(1), FEV(1)/FVC ratio and MMF were significantly lower in the CBA group than in the FBA group (P < 0.05, P < 0.05 and P < 0.05, respectively) and the non-BA group (P < 0.01, P < 0.01 and P < 0.05, respectively). Sputum eosinophils were significantly higher in the CBA group than in the FBA and non-BA groups (P < 0.01).


CONCLUSIONS
This study shows that subjects with long-term outgrown asthma continue to have airway eosinophilic inflammation, airway hyperresponsiveness and airway narrowing.
Hara
Johsuke
J
Respiratory Medicine, Cellular Transplantation Biology, Kanazawa University Graduate School of Medicine, Ishikawa, Japan. hara@ipch.jp
Fujimura
Masaki
M
Myou
Shigeharu
S
Kita
Toshiyuki
T
Abo
Miki
M
Katayama
Nobuyuki
N
Furusho
Shiho
S
Nobata
Kouichi
K
Oribe
Yoshitaka
Y
Kimura
Hideharu
H
Sone
Takashi
T
Waseda
Yuko
Y
Ichikawa
Yukari
Y
Araya
Tomoyuki
T
Ohkura
Noriyuki
N
Tamori
Shunichi
S
Takato
Hazuki
H
Tambo
Yuichi
Y
Herai
Yoriko
Y
Hori
Akihiro
A
Yasui
Masahide
M
Kasahara
Kazuo
K
Nakao
Shinji
S
D000328:Adult; D001249:Asthma / Q000276:immunology* / Q000503:physiopathology; D016535:Bronchial Hyperreactivity / Q000276:immunology* / Q000503:physiopathology; D016022:Case-Control Studies; D004802:Eosinophilia / Q000276:immunology*; D005260:Female; D006801:Humans; D008297:Male; D012129:Respiratory Function Tests; D013183:Sputum / Q000276:immunology*; D055815:Young Adult