TABLE 2

Best-performing models on multivariable Cox proportional hazards analysis

	Hazard ratio (95% CI)	Significance	Model significance
Baseline variables^#
Male	2.278 (1.126–4.608)	0.022	<0.001
LTOT initiation	2.050 (1.156–3.636)	0.014
FVC	1.020 (0.999–1.041)	0.058
D_LCO	0.985 (0.970–1.000)	0.044
Inability to perform D_LCO assessment	2.915 (1.380–6.158)	0.005
12-month follow-up^¶
D_LCO	0.953 (0.931–0.974)	<0.001	<0.001
Change in D_LCO	0.984 (0.972–0.997)	0.014
Male	1.933 (0.886–4.219)	0.098

Data are presented as mean (95% CI), unless otherwise stated. LTOT: long-term oxygen therapy; FVC: forced vital capacity; D_LCO: diffusing capacity of the lung for carbon monoxide. ^#: n=167; ^¶: n=126.