Cardiopulmonary exercise factors predict survival in patients with advanced interstitial lung disease referred for lung transplantation.

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.