Table 2 Univariate Cox proportional-hazard analysis

Age, y

1.005 (0.979–1.031)

0.72

Male gender

0.725 (0.394–1.334)

0.30

BMI, kg/m²

0.882 (0.826–0.942)

<0.001

PaO₂, mmHg

0.978 (0.961–0.996)

0.014

FVC, % predicted

0.954 (0.941–0.967)

<0.001

DLco, % predicted

0.976 (0.964–0.989)

<0.001

MMRC

1.413 (1.14–1.753)

0.002

BDI

0.830 (0.764–0.903)

<0.001

6MWD, m

0.996 (0.994–0.998)

<0.001

SpO₂ nadir, %

0.962 (0.944–0.98)

<0.001

 Symptom

1.019 (1.01–1.029)

<0.001

 Activity

1.014 (1.006–1.022)

0.001

 Impact

1.019 (1.009–1.029)

<0.001

 Total

1.021 (1.011–1.032)

<0.001