The Role of Cardiopulmonary Exercise Test in IPF Prognosis

Table 3

Significant predictors of survival among the variables of CPET and 6MWT in IPF patients.

Variables	Wald test	Score (log rank); test	HR	CI (95%)	Sum-index
VE/VCO2 slope	0.001	0.0002	1.09	1.04–1.15	0.0017
VO2 peak/kg	0.001	0.0004	0.75	0.60–0.95	0.0033
DLCO%	0.002	0.0007	0.88	0.80–0.96	0.0035
Distance (meters)	0.003	0.0008	0.99	0.98–1.00	0.0047
VE/VCO2 ratio at AT	0.006	0.0001	1.15	1.04–1.26	0.0074
Desaturation (%)	0.007	0.0025	1.45	1.11–1.90	0.0102

Minute ventilation (VE), carbon dioxide output (VCO₂), peak oxygen consumption/kg (VO₂ peak/kg), diffusing capacity for carbon monoxide% (DLCO%), VE/VCO₂ slope at anaerobic threshold (AT), and hazard ratio (HR).