Patient-reported Tests Can Predict Mortality, Lung Transplant Risk, Study Says
How idiopathic pulmonary fibrosis (IPF) patients assess their own symptoms and physical capacity predicts, to some degree, their risk of dying or of needing a lung transplant, according to a recent study.
The study, “Associations Between Patient-Reported Outcomes and Death or Lung Transplant in Idiopathic Pulmonary Fibrosis. Data from the Idiopathic Pulmonary Fibrosis Prospective Outcomes Registry,” was published in the journal Annals of the American Thoracic Society.
IPF is a progressive lung disease that can severely impair the patients’ health-related quality of life (HRQOL), particularly with regard to their symptoms, emotional well-being, and physical capacity.
How people with IPF experience their condition provides important information about the state of their health and the progress of their disorder. Although clinical tests, such as those assessing pulmonary function, are commonly used to categorize patients based on a perceived risk, the predictive value of patient-reported outcomes is less certain.
Researchers thus analyzed 662 patient records from the IPF-PRO (IPF Prospective Outcomes) Registry (NCT01915511) to look for associations between patient-reported outcomes at enrollment and death or lung transplant over the following year.
The IPF-PRO is an ongoing observational U.S. registry of patients with confirmed IPF. The registry uses four questionnaires to record patient-reported outcomes: the Cough and Sputum Assessment Questionnaire (CASA-Q), the St. George’s Respiratory Questionnaire (SGRQ), the Short Form-12 Questionnaire (SF-12), and the EuroQoL score and EuroQoL visual analog scale (VAS).
Of the 662 patients evaluated, 45 died and 12 underwent lung transplant over the course of one year.
The SGRQ — a 50-item survey of lung-related impacts on overall health, daily life, and perceived well-being — captured the strongest associations between HRQOL scores and clinical outcome. Patients who reported lower SGRQ scores were more likely to die or need a lung transplant over the course of the year.
These associations held up when adjusted for age and various clinical characteristics known to be associated with an increased risk of death or lung transplant — 1.22 times higher risk of death or lung transplant over one year per 10-point change in SGRQ total score.
Self-reported outcomes showed stronger associations with the risk of death or lung transplant than did the forced vital capacity (FVC) test, a standard clinical measure of lung function.
These results support past findings, as studies have shown that difficulty in performing the 6-minute walking test (a test of exercise capacity) and reductions in self-reported daily activities are associated with higher mortality among IPF patients.
Of the patient-reported outcomes analyzed in the study, only the SF-12 mental component score did not associate with death or lung transplant. This score assesses the emotional impact of a disease, which, while vital to overall patient care, may not capture information linked to IPF’s physiological progression.
Overall, the results suggest that “patient-reported outcomes assessing symptoms and capacity for physical activity represent independent predictors of death or lung transplant in patients with IPF,” the researchers wrote.
The team believes that “a multifaceted approach, including assessment of patient-perceived HRQL, may help to identify patients at greatest risk of disease progression,” although the researchers emphasized that further analysis of long-term data is needed to “investigate the extent to which changes in patient-reported outcomes over time are associated with mortality in patients with IPF.”