Abstract Background idiopathic pulmonary fibrosis (IPF) is a progressive, life-limiting disease in which dyspnea is the dominant symptom and a major driver of the disease burden. We aimed to assess dyspnea multidimensionally and to examine its associations with lung function and patient-reported outcomes. Methods we conducted a prospective, multicenter study across four French university hospitals. Adults with IPF (according to ATS/ERS 2018 guidelines) and dyspnea (VAS ≥ 1 or mMRC ≥ 1) were assessed at baseline (M0) and 6 months (M6). The primary endpoint was the total score of the Multidimensional Dyspnea Profile (MDP) sensory domain (QS); the secondary endpoint was the total score of the MDP affective domain (A2). Assessments included spirometry, body plethysmography, respiratory oscillometry, ventilatory variability, 6-minute walk test (6MWT), and questionnaires (SOBQ, K-BILD, STAI-Y2). Nonparametric analyses were performed, including Wilcoxon signed-rank tests for paired samples and Spearman rank-order correlation. Results fifty-three patients were included between October 2021 and October 2024 (83% men, median age 72 years), 88.7% (n = 47) received antifibrotics and 13% long-term oxygen therapy. Time since diagnosis was 3.8 years 1.8-6.4, median mMRC was 2 1-3, FVC 79% 67-96 and DLCO 39.5% 29.5-53.5. At baseline, median QS was at 9.5 3-17.5/50 and A2 at 8 2-18/50. Predominant sensations were “air hunger” and “breathing a lot”, and the main emotion was “anxiety”. Both QS and A2 correlated significantly with SOBQ (ρ = 0.599, p 0.001 and ρ = 0.602, p 0.001), K-BILD (ρ = −0.625, p 0.001 and ρ = −0.633, p 0.001), DLCO (ρ = −0.376, p = 0.009 and ρ = −0.318, p = 0.027), 6MWT SpO2 nadir (ρ = −0.377, p = 0.009 and ρ = −0.314, p = 0.031), X5expi (ρ = 0.329, p = 0.025 and ρ = 0.307, p = 0.036), resonant frequency (ρ = 0.376, p = 0.009 and ρ = 0.327, p = 0.023) and were higher for patients who had undergone pulmonary rehabilitation (17.5 12-24 vs. 5.5 2-14.5, p 0.001 for QS and 14.5 5.5-21.5 vs. 5 1-5, p = 0.023 for A2). No associations were observed with age, sex, FVC, or coefficients of variation of respiratory cycles parameters. At M6, 49 patients were analyzed (4 deaths). We observed no significant change in QS (0 −5-6, p = 0.982) and A2 (−1 −3-4, p = 0.807). Variation in QS was associated with older age (ρ = 0.363, p = 0.011), TLC decline (ρ = −0.356, p = 0.023), and PaO2 decrease (ρ = −0.504, p = 0.038; n = 17), whereas variation in A2 was associated with K-BILD decline (ρ = −0.386, p = 0.006). Conclusions In patients with IPF predominantly treated with antifibrotics, dyspnea severity was moderate, closely linked to impaired quality of life, and associated with hypoxemia and altered respiratory mechanics. This abstract is funded by: Santelys
Tazibet et al. (Fri,) studied this question.