Abstract
More sensitive biomarkers are highly needed to facilitate the development of novel respiratory drugs. This abstract aims to assess the changes in image-based airway volumes (iVaw) and resistances (iRaw) in relation to changes in FEV1 after bronchodilation. Both iVaw and iRaw are determined using FRI, a novel HRCT-based approach to generate imaging biomarkers. In total 128 subjects (79 asthma and 49 COPD patients) were included in the analyses. For all patients an inspiratory and expiratory HRCT scan was taken at baseline and after bronchodilation. In the asthmatic patients acute bronchodilation did increase FEV1 by 7.37±5.98%pred while iVaw did increase by 28.40±31.32% and iRaw did decrease by 33.53±30.44%. In COPD patients, the FEV1 increased by 4.57±5.45%pred, the iVaw increased by 20.83±36.97% and iRaw decreased 25.63±33.81%. Opening the black box of the respiratory system and eliminating the confounding effects of muscle force and patient effort appears to enhance the signal of the bronchodilating effect with a factor 3.34 for iVaw and 3.86 for iRaw. In addition, the regional information that FRI provides allows understanding what parts of the lung drive changes in FEV1. Next steps comprise of performing multi-regression analysis to determine predictors for FEV1 change. FRI appears to be promising as a biomarker for drug development. [figure2]
- Copyright ©ERS 2015
