Abstract
Objective: To elucidate the correlation between two disease-specific severity measures (CPI, composite physiologic index; GAP, gender, age, lung physiology variables) and health-related quality of life in patients with idiopathic pulmonary fibrosis (IPF). Methods: We used data from a previously reported observational cohort study using the Medical Outcome Study Short Form 36 (SF-36) for measuring health-related quality of life. Of the 44 patients with IPF who participated in the initial cross-sectional study, 32 patients participated in the follow-up study. The CPI and the GAP index were calculated at baseline and follow-up. Results: In the cross-sectional study, the CPI only correlated with one SF-36 domain and the GAP index did not correlate with any of the SF-36 domains. In the current longitudinal study (the median follow-up; 14 months), there was a significant increase in both indices: ΔCPI = 11.5 (95% confidence interval; 6.8, 16.1) and ΔGAP index = 0.59 (95% confidence interval; 0.25, 0.93). Within-subject changes in the CPI and the GAP index were significantly correlated with those of 5 and 3 subscales of the SF-36, respectively. Declines in 4 subscales of the SF-36 were significantly more severe in subjects whose CPI increased by ≥ 5 than in subjects whose CPI did not. Similarly, declines in 3 subscales were significantly more severe in subjects whose GAP stage increased than in subjects whose GAP stage did not. Conclusion: Serial changes in the CPI and the GAP index may be useful to predict changes in the healthrelated quality of life of IPF patients.
Highlights
Idiopathic pulmonary fibrosis (IPF) is a progressive, lifethreatening, interstitial lung disease of unknown etiology
Our previous study [3] examined health-related quality of life (HRQL) in IPF patients and showed that some clinical parameters, including those identified by physiologic evaluations such as vital capacity or 6-min-walk distance, were significantly related to the HRQL scores in the cross-sectional study and changes in scores in the longitudinal study; the HRQL and its longitudinal changes were incompletely predicted by these clinical parameters
The composite physiologic index (CPI) was only significantly correlated with physical function (ρ=-0.32, p
Summary
Idiopathic pulmonary fibrosis (IPF) is a progressive, lifethreatening, interstitial lung disease of unknown etiology. While halting disease progression and improving survival have long been the focus of IPF treatment, improving quality of life is extremely important for many patients and is perhaps a more realistic goal at this time [1,2]. Health status and health-related quality of life (HRQL) are common research outcomes in patients with chronic pulmonary diseases. Our previous study [3] examined HRQL in IPF patients and showed that some clinical parameters, including those identified by physiologic evaluations such as vital capacity (as percent of predicted) or 6-min-walk distance, were significantly related to the HRQL scores in the cross-sectional study and changes in scores in the longitudinal study; the HRQL and its longitudinal changes were incompletely predicted by these clinical parameters
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
