Table 2. Cox proportional hazard model for OS.
| Variables | Univariable analysis | Multivariable analysis | |||
|---|---|---|---|---|---|
| HR (95% CI) | P value | HR (95% CI) | P value | ||
| Male sex | 1.03 (0.61–1.72) | 0.923 | |||
| Age ≥65 years | 2.03 (1.36–3.01) | <0.001 | 1.42 (0.92–2.19) | 0.118 | |
| Extensive stage | 2.82 (1.85–4.29) | <0.001 | 2.25 (1.44–3.53) | <0.001 | |
| ECOG PS ≥2 | 3.08 (2.08–4.57) | <0.001 | 1.53 (0.97–2.44) | 0.070 | |
| Supportive care only | 11.28 (6.51–19.53) | <0.001 | 6.75 (3.78–12.04) | <0.001 | |
| Smoking history (yes vs. no) | 1.29 (0.74–2.25) | 0.370 | |||
| Charlson comorbidity index ≥1 | 1.32 (0.89–2.00) | 0.166 | |||
| Elevated LDH (≥486 U/L) | 1.70 (1.16–2.48) | 0.006 | 1.42 (0.96–2.11) | 0.079 | |
| COPD* | 1.65 (1.12–2.43) | 0.011 | 1.27 (0.86–1.87) | 0.224 | |
| CT-emphysema score† | 1.93 (1.02–1.08) | <0.001 | 1.03 (1.00–1.06) | 0.046 | |
*, Information regarding the presence of COPD was missing for 13 patients; †, analyzed as a continuous variable. ECOG PS, Eastern Cooperative Oncology Group performance status; LDH, lactate dehydrogenase; COPD, chronic obstructive pulmonary disease; HR, hazard ratio; CI, confidence interval; CT, computed tomography; OS, overall survival.