Fig. 3

Absolute changes in %FVC from baseline in the entire cohort and the matched cohort. Between-group differences in the absolute changes in %FVC from baseline (Δ%FVC) described as the mean (SD) at the 6-, 12-, and 24-month follow-ups were compared. Solid and dotted lines represent the PDN group and the non-PDN group, respectively. a In the entire cohort, the Δ%FVC in the PDN group was significantly different from that in the non-PDN group at 6 months (4.0% [8.8] vs − 3.2% [3.8], P < 0.001), 12 months (2.9% [10.0] vs − 5.5% [6.5], P < 0.001), and 24 months (0.8% [11.8] vs − 10.3% [9.8], P < 0.001). P-values were obtained with the Mann–Whitney U test. b In the matched cohort, the Δ%FVC in the PDN group was significantly different from that in the non-PDN group at 6 months (6.6% [8.2] vs − 3.2% [3.6], P < 0.001), 12 months (5.0% [9.7] vs − 4.9% [5.6], P < 0.001), and 24 months (0.9% [13.4] vs − 9.4% [8.6], P = 0.001). P-values were obtained with the Wilcoxon signed-rank test. A *** indicates a P-value < 0.001, a ** indicates a P-value < 0.01. FVC forced vital capacity; PDN prednisolone; SD standard deviation