Background: Lung function measurements are useful objective indices to monitor asthma control in children. Recently, a new forced oscillation technique machine called MostGraph (Chest Co. Ltd., Tokyo, Japan) has been developed to diagnose and monitor asthma. We assessed the utility of MostGraph in asthmatic children.
Methods: We evaluated 66 well controlled asthmatic children (11±3 yrs). For each subject, we measured respiratory function using MostGraph and spirometry and assessed the relationship between the two indices.
Results: MostGraph measurements were significantly correlated with age and body height. R5 was remarkably associated with FEV1% by analyzing partial correlation that excluded the factor of height. In addition, R5-R20 and Fres were significantly related to FEV1% and MMF. Furthermore, R5-R20 and Fres were significantly associated with MMF through multiple regression analyses for MostGraph parameters, the height and spirometory parameters. We classified asthmatic children into two groups with 70% of V25 cut point. Group with V25 below 70% had higher scores for R5-R20, Fres and ALX, compared to group with V25 above 70%.
Conclusion: MostGraph could be effectively used for the R5-R20 and Fres lung function measurements to assess asthma control in children. The results also suggested that R5-R20 and Fres might be parameters of small airway dysfunction.