Abstract
Introduction: Most studies on lung function parameters to predict of mortality in COPD focus on the FEV1.We aimed to assess the prognostic value of the transfer factor for carbon monoxide (TLCO) expressed as Z-score for mortality in COPD.
Methods: Patients from a COPD cohort (COMIC) with regular TLCO measurements within the follow-up window were included. Z-scores were calculated using the 2017 GLI reference values. Cox proportional hazard regression models were used to calculate the association of TLCO Z-score and other lung function parameters or demographics with survival.
Results: 275 participants had a valid TLCO measurement (57% male, age 65±9y) of which 52% died within follow-up. Mean follow-up after TLCO measurement was 6.0±2.8 years. Mean Z-score for FEV1 was -3.14±1.05 and mean Z-score for TLCO was -3.07±1.91. In univariate analysis, TLCO Z-score was significantly associated with survival (HR = 0.81, 95%CI 0.75-0.87). Survival curves for the TLCO Z-score quartile groups are shown in figure 1. Multivariate analysis with TLCO Z-score, FEV1 Z-score, age, sex and BMI as covariates resulted in a model to which only age (HR=1.1, 95%CI 1.0 – 1.1), sex (HR=1.8, 95%CI 1.3 – 2.6) and TLCO Z-score (HR=0.7, 95%CI 0.7 – 0.8) added significantly to the association with survival.
Conclusion: TLCO Z-score is associated with mortality in COPD. FEV1 does not add to the predictive value.
Footnotes
Cite this article as: European Respiratory Journal 2020; 56: Suppl. 64, 150.
This abstract was presented at the 2020 ERS International Congress, in session “Respiratory viruses in the "pre COVID-19" era”.
This is an ERS International Congress abstract. No full-text version is available. Further material to accompany this abstract may be available at www.ers-education.org (ERS member access only).
- Copyright ©the authors 2020