Association of patient-reported outcome measures with lung function and mortality in fibrotic interstitial lung disease: a prospective cohort study

Background Patient-reported outcome measures (PROMs) may provide clinicians and researchers with direct insights into disease impact and patient well-being. We assessed whether selected PROMs and their domains are associated with baseline and longitudinal changes in lung function and can predict mortality in patients with fibrotic interstitial lung disease (f-ILD). Methods A single-centre prospective study of adult patients with f-ILD enrolled over 3 years was conducted assessing baseline and short-term changes in PROMs. Three questionnaires, the modified Medical Research Council dyspnoea scale (mMRC), Chronic Respiratory Questionnaire (CRQ) and Self-Management Ability Scale (SMAS-30) were administered at planned intervals and assessed for their association with baseline clinical findings, change in lung function (% predicted forced vital capacity (FVC%) and diffusion capacity of the lung for carbon monoxide (D_LCO%)) and all-cause mortality. Results 199 patients were enrolled with a mean PROM follow-up of 9.6 months. When stratified by FVC % quartiles at presentation, lower mMRC (less dyspnoea), higher CRQ Physical and Emotional domain (better health-related quality of life) and higher total SMAS-30 scores (better self-management ability) were associated with higher FVC%. Short-term changes in all three PROMs appeared to be associated with changes in FVC% and D_LCO%. Adjusted and unadjusted baseline and serial PROM changes were also predictive of mortality. Conclusions Baseline and serial assessments of PROMs were associated with changes in lung function and predicted death in patients with f-ILD. PROMs may strengthen comprehensive assessments of disease impact in clinical practice as well as support patient-centred outcomes in research.