TY - JOUR
T1 - Trajectories and Prognostic Significance of 6-Minute Walk Test Parameters in Fibrotic Interstitial Lung Disease
T2 - A Multicenter Study
AU - Khor, Yet H.
AU - Farooqi, Malik
AU - Hambly, Nathan
AU - Johannson, Kerri A.
AU - Marcoux, Veronica
AU - Fisher, Jolene H.
AU - Assayag, Deborah
AU - Manganas, Helene
AU - Khalil, Nasreen
AU - Kolb, Martin
AU - Ryerson, Christopher J.
AU - for the Austin ILD Registry and CARE-PF Investigators
N1 - Publisher Copyright:
© 2022 American College of Chest Physicians
PY - 2023/2
Y1 - 2023/2
N2 - Background: Functional capacity, as measured by the 6-min walk test (6MWT), is often reduced in fibrotic interstitial lung disease (ILD). This study evaluated longitudinal changes and the prognostic significance of 6MWT parameters, and explored change in oxygenation status as a physiological criterion to define disease progression in patients with fibrotic ILD. Research Questions: What are the trajectories and prognostic value of 6MWT parameters in patients with fibrotic ILD? Study Design and Methods: Using prospective registries in Australia and Canada, patients with idiopathic pulmonary fibrosis (IPF) and non-IPF fibrotic ILD were stratified by the presence of criteria for progressive pulmonary fibrosis (PPF). The cumulative incidence of exertional and resting hypoxemia and changes in 6-min walk distance (6MWD) and composite indices (distance-saturation product and distance-saturation-oxygen product) were determined, with prognostic significance evaluated at the time of meeting criteria for PPF. New-onset exertional or resting hypoxemia was evaluated as another potential criterion for PPF. Results: Patients with IPF/PPF (n = 126) and non-IPF/PPF (n = 227) had a similar cumulative incidence of exertional hypoxemia and annualized decline in 6MWD and composite indices, which varied across each PPF criterion. Patients with IPF/non-PPF (n = 231) and non-IPF/non-PPF (n = 531) had a significantly lower incidence of hypoxemia than those with IPF/PPF, with an annualized increase in 6MWD and composite indices in the non-IPF/non-PPF group. Exertional or resting hypoxemia at the time of meeting criteria for PPF was independently associated with reduced transplant-free survival in IPF and non-IPF, adjusting for patient demographics and lung function. Adding new-onset exertional or resting hypoxemia as a physiological criterion reduced the median time to development of PPF from 11.2 to 6.7 months in IPF and from 11.7 to 5.6 months in non-IPF in patients who eventually met both definitions (P < .001 for both). Interpretation: Patients with IPF/PPF and non-IPF/PPF have comparable deterioration in functional capacity. Oxygenation status provides prognostic information in PPF and may assist in defining disease progression in fibrotic ILD.
AB - Background: Functional capacity, as measured by the 6-min walk test (6MWT), is often reduced in fibrotic interstitial lung disease (ILD). This study evaluated longitudinal changes and the prognostic significance of 6MWT parameters, and explored change in oxygenation status as a physiological criterion to define disease progression in patients with fibrotic ILD. Research Questions: What are the trajectories and prognostic value of 6MWT parameters in patients with fibrotic ILD? Study Design and Methods: Using prospective registries in Australia and Canada, patients with idiopathic pulmonary fibrosis (IPF) and non-IPF fibrotic ILD were stratified by the presence of criteria for progressive pulmonary fibrosis (PPF). The cumulative incidence of exertional and resting hypoxemia and changes in 6-min walk distance (6MWD) and composite indices (distance-saturation product and distance-saturation-oxygen product) were determined, with prognostic significance evaluated at the time of meeting criteria for PPF. New-onset exertional or resting hypoxemia was evaluated as another potential criterion for PPF. Results: Patients with IPF/PPF (n = 126) and non-IPF/PPF (n = 227) had a similar cumulative incidence of exertional hypoxemia and annualized decline in 6MWD and composite indices, which varied across each PPF criterion. Patients with IPF/non-PPF (n = 231) and non-IPF/non-PPF (n = 531) had a significantly lower incidence of hypoxemia than those with IPF/PPF, with an annualized increase in 6MWD and composite indices in the non-IPF/non-PPF group. Exertional or resting hypoxemia at the time of meeting criteria for PPF was independently associated with reduced transplant-free survival in IPF and non-IPF, adjusting for patient demographics and lung function. Adding new-onset exertional or resting hypoxemia as a physiological criterion reduced the median time to development of PPF from 11.2 to 6.7 months in IPF and from 11.7 to 5.6 months in non-IPF in patients who eventually met both definitions (P < .001 for both). Interpretation: Patients with IPF/PPF and non-IPF/PPF have comparable deterioration in functional capacity. Oxygenation status provides prognostic information in PPF and may assist in defining disease progression in fibrotic ILD.
KW - 6-min walk test
KW - hypoxemia
KW - idiopathic pulmonary fibrosis
KW - interstitial lung disease
KW - progressive pulmonary fibrosis
UR - http://www.scopus.com/inward/record.url?scp=85142544397&partnerID=8YFLogxK
U2 - 10.1016/j.chest.2022.08.2233
DO - 10.1016/j.chest.2022.08.2233
M3 - Article
C2 - 36089070
AN - SCOPUS:85142544397
SN - 0012-3692
VL - 163
SP - 345
EP - 357
JO - Chest
JF - Chest
IS - 2
ER -