Table 2. Univariable analysis of PFS, OS and ORR for clinically important factors.
| Parameter | PFS | OS | ORR | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| HR | 95% CI | P value | HR | 95% CI | P value | OR | 95% CI | P value | |||
| ECOG PS (0 vs. ≥1) | 0.64 | 0.30–1.16 | 0.14 | 0.51 | 0.24–1.05 | 0.06 | 1.13 | 0.97–1.31 | 0.12 | ||
| Histologic subtype (non-epithelioid vs. epithelioid) | 1.02 | 0.60–1.76 | 0.91 | 1.71 | 0.92–3.16 | 0.08 | 1.03 | 0.89–1.20 | 0.65 | ||
| PD-L1 status (positive vs. negative) | 0.52 | 0.23–1.20 | 0.12 | 0.67 | 0.27–1.64 | 0.39 | 1.31 | 1.00–1.72 | 0.05 | ||
| Age | 1.00 | 0.97–1.02 | 0.90 | 1.00 | 0.97–1.03 | 0.76 | 0.99 | 0.98–1.00 | 0.25 | ||
| Gender (male vs. female) | 1.45 | 0.70–3.01 | 0.31 | 1.56 | 0.62–3.92 | 0.33 | 0.93 | 0.77–1.11 | 0.44 | ||
| Clinical stage (stage III/IV vs. I/II) | 1.82 | 1.11–3.01 | 0.02 | 1.27 | 0.71–2.28 | 0.41 | 0.93 | 0.81–1.06 | 0.29 | ||
| Line of treatment | 0.76 | 0.35–1.66 | 0.49 | 0.89 | 0.35–2.23 | 0.80 | 1.11 | 0.91–1.35 | 0.29 | ||
| TTP to first-line chemotherapy (<6 vs. ≥6 months) | 1.42 | 0.91–2.19 | 0.11 | 1.57 | 0.93–2.62 | 0.09 | 1.06 | 0.94–1.20 | 0.29 | ||
| TI from diagnosis to nivolumab | 0.98 | 0.95–1.02 | 0.32 | 0.98 | 0.94–1.03 | 0.44 | 1.00 | 0.99-1.01 | 0.58 | ||
| BMI | 0.99 | 0.93–1.07 | 0.99 | 0.96 | 0.89–1.03 | 0.31 | 1.00 | 0.99–1.01 | 0.29 | ||
The univariable Cox proportional hazard model was used to calculate the HRs of progression or death and the univariable logistic regression was used to calculate the ORs of response. PFS, progression-free survival; OS, overall survival; ORR, objective response rate; HR, hazard ratio; OR, odds ratio; CI, confidence interval; ECOG PS, Eastern Cooperative Oncology Group Performance Status; PD-L1, programmed death ligand 1; TTP, time to progression; TI, time interval; BMI, body mass index.