Bronchodilator response cut-off points and FEV 0.75 reference values for spirometry in preschoolers

• Main Authors: Edjane Figueiredo Burity, Carlos Alberto de Castro Pereira, Marcus Herbert Jones, Larissa Bouwman Sayão, Armèle Dornelas de Andrade, Murilo Carlos Amorim de Britto
• Format: Article
• Language: English
• Published: Sociedade Brasileira de Pneumologia e Tisiologia
• Series: Jornal Brasileiro de Pneumologia
• Subjects: Spirometry; Bronchodilator agents; Reference values; Child, preschool
• Online Access: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1806-37132016000500326&lng=en&tlng=en

ABSTRACT Objective: To determine the cut-off points for FEV1, FEV0.75, FEV0.5, and FEF25-75% bronchodilator responses in healthy preschool children and to generate reference values for FEV0.75. Methods: This was a cross-sectional community-based study involving children 3-5 years of age. Healthy preschool children were selected by a standardized questionnaire. Spirometry was performed before and after bronchodilator use. The cut-off point of the response was defined as the 95th percentile of the change in each parameter. Results: We recruited 266 children, 160 (60%) of whom were able to perform acceptable, reproducible expiratory maneuvers before and after bronchodilator use. The mean age and height were 57.78 ± 7.86 months and 106.56 ± 6.43 cm, respectively. The success rate for FEV0.5 was 35%, 68%, and 70% in the 3-, 4-, and 5-year-olds, respectively. The 95th percentile of the change in the percentage of the predicted value in response to bronchodilator use was 11.6%, 16.0%, 8.5%, and 35.5% for FEV1, FEV0.75, FEV0.5, and FEF25-75%, respectively. Conclusions: Our results provide cut-off points for bronchodilator responsiveness for FEV1, FEV0.75, FEV0.5, and FEF25-75% in healthy preschool children. In addition, we proposed gender-specific reference equations for FEV0.75. Our findings could improve the physiological assessment of respiratory function in preschool children.