Table 3.

Multivariate Cox-Proportional Hazards Model for Progression-Free and Overall Survival

Characteristic	Category	Progression-Free Survival (PFS)		Overall Survival (OS)
		HR (95% CI)	p-value	HR (95% CI)	p-value
Gender
	Female	1		1
	Male	0.793 (0.574–1.096)	0.160	0.830 (0.579–1.189)	0.309
Age
	<65 years	1		1
	≥65 years	0.877 (0.657–1.170)	0.371	0.891 (0.649–1.224)	0.477
ECOG PS
	1	1		1
	0	0.665 (0.487–0.909)	0.010	0.665 (0.479–0.924)	0.015
BMI
	Low (≤25)	1		1
	High (>25)	1.090 (0.768–1.547)	0.630	1.349 (0.914–1.990)	0.132
Histology
	Clear cell carcinoma	1		1
	Other	2.286 (1.184–4.414)	0.014	1.970 (0.974–3.984)	0.059
Grade
	G1-G2	1		1
	G3-G4	1.417 (1.043–1.926)	0.026	1.889 (1.351–2.640)	<0.001
Synchronous metastases
	No	1		1
	Yes	0.943 (0.660–1.348)	0.748	0.935 (0.635–1.376)	0.732
MSKCC risk group
	Favorable-risk group	1		1
	Intermediate-risk group	0.987 (0.724–1.345)	0.932	1.310 (0.944–1.820)	0.106
Previous nephrectomy
	No	1		1
	Yes	0.699 (0.439–1.115)	0.133	0.557 (0.336–0.921)	0.023
First-line targeted therapy
	Sunitinib	1		1
	Pazopanib	1.028 (0.700–1.509)	0.889	1.094 (0.719–1.666)	0.674
Metformin use
	No	1		1
	Yes	0.550 (0.343–0.883)	0.013	0.450 (0.256–0.794)	0.006

Note: Bold indicates p<0.05.

Abbreviations: n, number of included patients; ECOG PS, Eastern Cooperative Oncology Group performance status; MSKCC, Memorial Sloan–Kettering Cancer Center (MSKCC) risk; BMI, body mass index; G1, well differentiated; G2, moderately differentiated; G4, poorly differentiated/undifferentiated.