Inspiratory capacity (IC) was significantly lower in subjects with DPTB and PPTB than in those with NPTB, and expiratory reserve volume (ERV) and functional residual capacity (FRC) were higher.
On multivariate analysis, D[LSUB.CO] (% predicted) was 17.7% (CI -27.91 - -7.57) and 10.9% lower (95% CI -21.14 - - 0.58) in DPTB and PPTB, respectively, than in NPTB (Tables 2 and 4, Fig.
HRCT fibrosis scores in DPTB, but not PPTB, were significantly higher than in NPTB, being 0.36% (95% CI 0.06-0.65; p=0.017) higher on multivariate analysis, but overall scores were low (Tables 4 and 5).
The mean gas trapping score on expiration was higher in both the DPTB (38.9%) and PPTB groups (32.8%) compared with the NPTB group (26.7%; p=0.006).
However, the WT4 in the RUL in DPTB and PPTB subjects combined was higher than in NPTB subjects (median 0.80 mm; (interquartile range (IQR) 0.6 1.1) v.