Table 4.

Cox proportional-hazards regression to identify factors associated with increased mortality

	B	Sig	HR	95% CI for Exp (B)
Age	0.046	0.545	0.954	0.811–1.112
FVC	−0.086	0.345	0.863	0.798–1.342
DLCO	−0.018	0.012	1.218	1.115–1.473
6MWT	−0.087	0.362	1.136	0.892–1.427
SPAP	0.018	0.234	1.018	0.989–1.050
PaO2	−0.523	0.078	1.842	0,912–2.419
RDW	0.906	0.023	1.658	1.096–2.478

B, regression coefficient; Exp (B), hazard ratio; CI, confidence interval; FVC, forced vital capacity; DLCO, carbon monoxide diffusing capacity; 6MWT, 6-minute walking test; SPAP, systolic pulmonary arterial pressure; PaO₂, partial oxygen pressure; RDW, red cell distribution width. Bold values denote statistical significance at the p < 0.05 level.