TABLE 4

Prognostic Factors for Overall Survival of Patients with IPF Using Univariate and Multivariate Cox Models

Model	HR	95% CI	P
Univariate Cox
Male sex	2.13	0.63–7.17	0.22
Ever-smoker	1.28	0.51–3.23	0.60
FVC (% predicted)	0.97	0.95–0.99	0.003^*
DL_CO (% predicted)	0.97	0.94–0.99	0.012^*
Resting PaO₂ (mm Hg)	0.98	0.95–1.01	0.15
6-min walk distance (m)	0.99	0.99–0.99	0.010^*
6-min walk test nadir SpO₂ (%)	0.92	0.85–0.99	0.041^*
Extent of fibrosis score (0–4)	2.00	1.25–3.18	0.004^*
Early SUV	1.70	0.50–5.85	0.40
Delayed SUV	2.96	1.20–7.27	0.018^*
RI-SUV (%)	1.05	1.02–1.09	0.0005^*
Multivariate Cox
RI-SUV (%)	1.05	1.01–1.08	0.007^*
FVC (% predicted)	0.97	0.95–0.99	0.020^*

↵* P < 0.05.
PaO₂ = arterial partial pressure of oxygen; SpO₂ = oxygen saturation.