title: Forced oscillation technique as a predictor of FEV1 improvement in asthma.
abstract: The usefulness of the forced oscillation technique (FOT) for predicting the treatment outcomes in untreated asthmatic patients is unknown. We investigated whether FOT could predict an improvement in FEV1 following treatment. FOT, spirometry, and fractional exhaled nitric oxide were performed in 31 outpatients before and after undergoing a minimum of two months combination therapy of inhaled corticosteroids and long-acting β2-agonists. The patients were classified as responders or nonresponders to treatment based on the presence or absence of a 10% improvement in the FEV1. The responders to the treatment regimen exhibited lower FEV1, FEV1/FVC, FEF25-75%, and higher respiratory resistance at 5Hz (R5), as well as a difference between R5 and R20 (R5-R20) at baseline compared to the nonresponders. In the multivariate logistic regression analyses, a change in FEV1 greater than 10% was independently predicted by the R5 (adjusted odds ratio: 15.9). The ROC curve analyses revealed that the area under the curve for R5 (0.731) was larger than that of the other parameters. Thus, R5 is a forced oscillatory parameter and predicts an improvement in FEV1 following treatment.
authors.affiliation: Department of Respiratory Medicine, Shizuoka General Hospital, Shizuoka, Japan.
authors.forename: Taisuke
authors.initials: T
authors.lastname: Akamatsu
authors.affiliation: Department of Respiratory Medicine, Shizuoka General Hospital, Shizuoka, Japan. Electronic address: toshihiro-shirai@i.shizuoka-pho.jp.
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Shirai
authors.affiliation: Department of Respiratory Medicine, Shizuoka General Hospital, Shizuoka, Japan.
authors.forename: Yukiko
authors.initials: Y
authors.lastname: Shimoda
authors.affiliation: Department of Respiratory Medicine, Shizuoka General Hospital, Shizuoka, Japan.
authors.forename: Takahito
authors.initials: T
authors.lastname: Suzuki
authors.affiliation: Department of Respiratory Medicine, Shizuoka General Hospital, Shizuoka, Japan.
authors.forename: Ichiro
authors.initials: I
authors.lastname: Hayashi
authors.affiliation: Department of Respiratory Medicine, Shizuoka General Hospital, Shizuoka, Japan.
authors.forename: Rie
authors.initials: R
authors.lastname: Noguchi
authors.affiliation: Department of Respiratory Medicine, Shizuoka General Hospital, Shizuoka, Japan.
authors.forename: Eisuke
authors.initials: E
authors.lastname: Mochizuki
authors.affiliation: Department of Respiratory Medicine, Shizuoka General Hospital, Shizuoka, Japan.
authors.forename: Shogo
authors.initials: S
authors.lastname: Sakurai
authors.affiliation: Department of Respiratory Medicine, Shizuoka General Hospital, Shizuoka, Japan.
authors.forename: Mika
authors.initials: M
authors.lastname: Saigusa
authors.affiliation: Department of Respiratory Medicine, Shizuoka General Hospital, Shizuoka, Japan.
authors.forename: Akito
authors.initials: A
authors.lastname: Yamamoto
authors.affiliation: Department of Respiratory Medicine, Shizuoka General Hospital, Shizuoka, Japan.
authors.forename: Yuichiro
authors.initials: Y
authors.lastname: Shishido
authors.affiliation: Department of Respiratory Medicine, Shizuoka General Hospital, Shizuoka, Japan.
authors.forename: Takefumi
authors.initials: T
authors.lastname: Akita
authors.affiliation: Department of Respiratory Medicine, Shizuoka General Hospital, Shizuoka, Japan.
authors.forename: Satoru
authors.initials: S
authors.lastname: Morita
authors.affiliation: Department of Respiratory Medicine, Shizuoka General Hospital, Shizuoka, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Asada
mesh_terms: D000305:Adrenal Cortex Hormones / Q000627:therapeutic use; D000322:Adrenergic Agonists / Q000627:therapeutic use; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000403:Airway Resistance / Q000187:drug effects / Q000502:physiology*; D018927:Anti-Asthmatic Agents / Q000627:therapeutic use; D001249:Asthma / Q000188:drug therapy / Q000503:physiopathology*; D005260:Female; D005541:Forced Expiratory Volume / Q000187:drug effects / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009569:Nitric Oxide / Q000378:metabolism; D009991:Oscillometry / Q000379:methods; D017063:Outcome Assessment, Health Care / Q000379:methods*; D012372:ROC Curve; D012044:Regression Analysis; D012189:Retrospective Studies; D013147:Spirometry / Q000379:methods; D014797:Vital Capacity / Q000187:drug effects / Q000502:physiology*
chemical_list: D000305:Adrenal Cortex Hormones; D000322:Adrenergic Agonists; D018927:Anti-Asthmatic Agents; D009569:Nitric Oxide
keywords: Asthma; FEV1; Forced oscillation technique; Lung function; Respiratory resistance; Spirometry