Table 2. Univariate and multivariable Cox proportional hazards regression analysis of covariables associated with OS and PFS.
| Variables | Univariate analysis | Multivariable analysis | |||
|---|---|---|---|---|---|
| HR (95% CI) | P value | HR (95% CI) | P value | ||
| OS | |||||
| Age (≥70 years) | 1.79 (1.03–3.12) | 0.04* | 1.45 (0.75–2.80) | 0.27 | |
| Sex (male) | 1.74 (1.09–2.77) | 0.02* | 1.64 (1.10–2.70) | 0.050* | |
| PS† | 1.47 (1.06–2.02) | 0.02* | 1.43 (0.98–2.08) | 0.07 | |
| Tumor stage M1c (yes) | 1.33 (0.84–2.11) | 0.22 | – | – | |
| Primary brain metastasis (yes) | 0.74 (0.40–1.37) | 0.33 | – | – | |
| Smokers (yes) | 2.41 (1.30–4.49) | 0.005* | 1.24 (0.63–2.42) | 0.53 | |
| TE (yes) | 2.80 (1.77–4.44) | <0.001* | 2.09 (1.27–3.46) | 0.004* | |
| Prior chemotherapy (yes) | 1.10 (0.68–1.71) | 0.76 | – | – | |
| Initial ALK-TKI (crizotinib) | 2.64 (1.51–4.61) | <0.001* | 2.17 (1.21–3.89) | 0.009* | |
| Chronic lung disease (yes) | 5.13 (2.27–11.59) | <0.001* | 3.71 (1.59–8.70) | 0.003* | |
| Variant 3a/b (yes) | 1.03 (0.60–1.75) | 0.92 | – | – | |
| PD-L1 negative (yes) | 0.68 (0.32–1.43) | 0.31 | – | – | |
| PFS | |||||
| Age (≥70 years) | 1.24 (0.76–2.04) | 0.40 | – | – | |
| Sex (male) | 1.26 (0.84–1.88) | 0.27 | – | – | |
| PS† | 1.17 (0.91–1.50) | 0.23 | – | – | |
| Tumor stage M1c (yes) | 0.95 (0.63–1.42) | 0.78 | – | – | |
| Primary brain metastasis (yes) | 0.57 (0.33–0.99) | 0.046* | 1.14 (0.61–2.14) | 0.68 | |
| Smokers (yes) | 1.90 (1.05–3.41) | 0.03* | 1.01 (0.53–1.93) | 0.98 | |
| No. previous lines of CT† | 1.17 (0.97–1.40) | 0.10 | – | – | |
| Prior chemotherapy (yes) | 1.76 (1.18–2.62) | 0.006* | 0.66 (0.41–1.08) | 0.10 | |
| Initial ALK-TKI (crizotinib) | 4.60 (2.91–7.27) | <0.001* | 5.41 (2.95–9.94) | <0.001* | |
| Chronic lung disease (yes) | 3.07 (1.40–6.73) | 0.005* | 1.92 (0.81–4.53) | 0.14 | |
| Variant 3a/b (yes) | 1.37 (0.86–2.19) | 0.19 | – | – | |
| PD-L1 negative (yes) | 0.35 (0.18–0.67) | 0.002* | 0.72 (0.35–1.51) | 0.39 | |
†, PS as ordinal variable and No. previous lines of CT as a continuous variable; *, clinical variables that are statistically significant between the groups. OS, overall survival; PFS, progression-free survival; HR, hazard ratio; CI, confidence interval; PS, performance status; TE, thromboembolism; ALK, anaplastic lymphoma kinase; TKI, tyrosine kinase inhibitor; PD-L1, programmed cell death-ligand 1; No., number; CT, chemotherapy.