Exploring small airways disease in IPF patients: insights from oscillometry analysis

<bold>Introduction:</bold> Small airway disease (SAD) in idiopathic pulmonary disease (IPF) has not been extensively studied. <bold>Aims:</bold> To investigate SAD in IPF patients by the means of oscillometry. <bold>Methods:</bold> In the IPF group, specialists recorded demographics, time from first diagnosis, antifibrotic treatment and treatment period, as well as detailed lung function including oscillometry using TremoFlo® c-100 (THORASYS Thoracic Medical Systems Inc., Montreal, QC, Canada), spirometry (Spirolab, MIR, Rome, Italy), and plethysmography (CardinalHealth, Yorba Linda, CA, USA). <bold>Results:</bold> A total of 48 IPF individuals, 69% were male, with an average age of 72±2 years, were included. The participants consisted of ex-smokers (63%), non-smokers (33%), and current smokers (6%) with an average of 47±38 pys. Approximately 54% of the patients received antifibrotic treatment (48% taking pirfenidone and 52% nintedanib). The mean R5, R5-20, AX, X5, Fres were 3±1 cmH2O/L/s, 0.5±0.4 cmH2O/L/s, 1.2±0.8 cmH2O/L/s, -0.18±0.07 cmH2O/L/s and 20±3.4 Hz, respectively. The study found increased R5, R5-R20, X5, and Fres values compared to literature ranges for healthy individuals measured with Tremoflo [1, 2], similar to those found in COPD patients [2], not detected with spirometry or plethysmography. Antifibrotic treatment was found to have no significant effect on lung function parameters, and smoking status was not associated with any changes in these parameters. <bold>Conclusions:</bold> IPF patients showed higher levels of central, and peripheral obstruction, and reactance in comparison to the normal ranges reported in the literature. [1] Goebel I et al. Toxics. 2023;11:758. [2] Lundblad LKA et al. Sci Rep. 2019;9:11618.