Table 4.

Univariate and multivariate analyses using Cox proportional hazards models using factors influencing OS

Characteristics	OS
	Univariate analysis	P-value	Multivariate analysis	P-value
	HR (95% CI)		HR (95% CI)
Age (years)
≤60	1 (reference)	<0.001	1 (reference)	<0.001
>60	1.785 (1.372–2.321)		1.701 (1.304–2.218)
Sex
Male	1 (reference)	0.053
Female	0.743 (0.550–1.004)
Smoking
Yes	1 (reference)	0.033	1 (reference)	0.020
No	0.748 (0.572–0.977)		0.717 (0.542–0.950)
Cell types
Adenocarcinoma	1 (reference)	0.003	1 (reference)	0.002
Squamous	0.741 (0.559–0.983)		0.687 (0.510–0.925)
Others	0.402 (0.223–0.724)		0.429 (0.237–0.775)
Tumor differentiation
Poorly or undifferentiated	1 (reference)	0.134
Well or moderately	0.820 (0.632–1.063)
Visceral pleura invasion
Yes	1 (reference)	0.403
No	0.893 (0.684–1.165)
Bronchial invasion
Yes	1 (reference)	0.024
No	0.689 (0.499–0.952)
Postoperative chemotherapy
Yes	1 (reference)	0.091
No	1.392 (0.948–2.044)
Resected lymph node numbers
<12	1 (reference)	0.016	1 (reference)	0.022
≥12	0.728 (0.563–0.942)		0.736 (0.567–0.956)
Resected lymph node stations
<6	1 (reference)	0.910
≥6	0.984 (0.742–1.305)
NLR
≤3.13	1 (reference)	0.072
>3.13	1.354 (0.974–1.884)
LMR
≤3.16	1 (reference)	0.001
>3.16	0.647 (0.499–0.839)
PLR
≤81.07	1 (reference)	0.009
>81.07	1.757 (1.151–2.682)
PNI
≤49.55	1 (reference)	0.014
>49.55	0.717 (0.551–0.934)
LMR-PLR
0	1 (reference)	0.001	1 (reference)	0.001
1	0.687 (0.524–0.899)		0.685 (0.523–0.898)
2	0.426 (0.261–0.934)		0.434 (0.265–0.710)

Note: P-value; in Cox hazards regression analysis, variables that were found to be statistically significant (P<0.05) in the univariate analysis were entered into a Cox regression multivariate model using a forward conditional method.

Abbreviations: LMR, lymphocyte-to-monocyte ratio; LMR-PLR, combination of preoperative LMR and PLR; NLR, neutrophil-to-lymphocyte ratio; OS, overall survival; PLR, platelet-to-lymphocyte ratio; PNI, prognostic nutritional index.