Trajectories of Health-Related Quality of Life in Patients With Idiopathic Pulmonary Fibrosis
Background Patients with idiopathic pulmonary fibrosis (IPF) experience impairments in health-related quality of life (HRQL). Research Question What is the trajectory of decline in HRQL in patients with IPF and is this influenced by patients’ demographic/clinical characteristics at baseline? Study Design and Methods The Idiopathic Pulmonary Fibrosis Prospective Outcomes (IPF-PRO) Registry is a registry of patients with IPF. HRQL was assessed at enrollment and during routine clinical care using the following patient-reported outcomes (PROs): the Cough and Sputum Assessment Questionnaire, the St. George’s Respiratory Questionnaire, the 12-item Short Form Survey, and the EuroQol score and visual analog scale. Trajectories of PRO scores were estimated using a mixed joint model. Associations between sex, age, FVC and diffusing capacity of the lungs for carbon monoxide (both % predicted), use of supplemental oxygen, and use of antifibrotic therapy at enrollment and trajectories of PRO scores were assessed. Results The cohort included 957 patients. Estimated mean changes in scores over 48 months were 10.8, 7.0, 13.1, and 10.5 for the St. George’s Respiratory Questionnaire total, symptoms, activity, and impact scores; −7.6 and −6.5 for the Cough and Sputum Assessment Questionnaire cough impact and symptoms scores; −2.1 and −7.0 for the 12-item Short Form Survey Mental Component Summary and Physical Component Summary scores; and −0.08 and −9.0 for the EuroQol score and visual analog scale, respectively ( P < .001 for all). At enrollment, female sex, lower age, lower FVC and diffusing capacity of the lungs for carbon monoxide % predicted, and use of supplemental oxygen were associated with worse PRO scores. Trajectories of decline in PRO scores were similar across levels of demographic/clinical factors assessed at enrollment. Interpretation Among patients in the IPF-PRO Registry, a range of PROs showed worsening in HRQL over 48 months. Female sex, lower age, worse lung function, and use of supplemental oxygen were associated with worse HRQL at enrollment and during follow-up. These findings suggest that interventions aimed at preserving HRQL in patients with IPF may be of particular benefit for certain groups of patients. Clinical Trial Registration ClinicalTrials.gov; No.: NCT01915511 ; URL: www.clinicaltrials.gov
