We evaluated relationships between changes in lung function and changes in patient-reported outcomes (PROs) in 736 patients with idiopathic pulmonary fibrosis (IPF) enrolled in the IPF-PRO Registry. Weak correlations were observed between changes in percent predicted values for forced vital capacity or diffusing capacity of the lungs (DLco) and changes in St George's Respiratory Questionnaire (SGRQ) total and activity scores and the 12-item Short Form Survey (SF-12) physical component summary score over 12-month periods. Patients who had a deterioration in SGRQ activity score or SF-12 PCS score of ≥ 5 units had numerically larger declines in lung function than other patients, but the differences were small. The weak relationships observed between changes in lung function and changes in PROs underscore the importance of evaluating both changes in lung function and changes in HRQL in clinical practice and clinical trials.
Todd et al. (Wed,) studied this question.