Layton AM, Armstrong HF, Kim HP, Meza KS, D’Ovidio F, Arcasoy SM.
Respir Med. 2017 May;126:59-67. doi: 10.1016/j.rmed.2017.03.022. Epub 2017 Mar
BACKGROUND: The purpose of this work was to determine if parameters assessed
during Cardiopulmonary Exercise Testing (CPET) while using supplemental oxygen
can independently predict one-year transplant-free survival in patients with
Interstitial Lung Disease (ILD) referred for lung transplant evaluation.
METHODS: We performed a chart review of patients with ILD who completed CPET with
30% FiO2 and gathered spirometry, pulmonary hemodynamic, six-minute walk, and
CPET data. The primary end-point was death or lung transplantation within
one-year of CPET.
RESULTS: The final data set included 192 patients. 79 patients died/underwent
transplant, 113 survived transplant-free. Multivariable Cox regression revealed
peak workload % predicted, nadir CPET SpO2, and FVC% predicted as independent
predictors of one-year transplant-free survival. Of the independent predictors of
survival, receiver operating characteristics analysis revealed peak workload
%predicted cutoff of 35% to be highly discriminatory, more so than nadir CPET
SpO2 or FVC % predicted in identifying patients at risk for one-year mortality or
transplant (peak workload % predicted < 35% HR = 4.71, 95% CI = 2.64-8.38 and area under the curve (AUC) = 0.740, nadir CPET SpO2 < 86% HR = 2.27, 95%CI = 1.41-3.68, AUC = 0.645, FVC %predicted <45% HR = 1.82, 95% CI = 1.15-2.87, AUC = 0.624). CONCLUSION: Peak workload % predicted, nadir CPET SpO2, and FVC% predicted in ILD patients referred for lung transplant evaluation are independently predictive of one-year mortality or need for transplant.