Table 2. Cox proportional hazards regression for mortality: Univariable and multivariable models for overall patients.

	Univariable		Multivariable
Variables	HR (95% CI)	P value	HR (95% CI)	P value
Anesthesia, Propofol (ref: Desflurane)	0.11 (0.03–0.47)	0.003	0.12 (0.03–0.54)	0.006
Time since the earliest op (yr)	1.24 (0.96–1.60)	0.095
Age (yr)	1.13 (1.06–1.22)	0.001	1.05 (0.87–1.28)	0.604
PSA >10 (ref: ≤ 10)	5.50 (2.07–14.6)	0.001	4.89 (1.74–13.7)	0.003
Charlson comorbidity index	2.81 (1.50–5.25)	0.001	1.54 (0.31–7.62)	0.600
Functional status, ≥4 METs (ref: <4 METs)	0.27 (0.10–0.72_	0.009
ASA III, (ref: II)	3.74 (1.40–10.0)	0.009	0.77 (0.17–3.53)	0.739
TNM stage of primary tumor (ref: I)
II	1.28 (0.38–4.31)	0.690
III	1.64 (0.27–9.86)	0.587
Tumor grade (ref: low+ medium risk)
High risk	0.92 (0.41–2.06)	0.838
Tumor size (cm)	1.10 (0.79–1.54)	0.572
Intraoperative blood transfusion (ref: no)	5.12 (1.75–14.9)	0.003	1.53 (0.28–8.20)	0.623
Grade of surgical complications (ref: 0)
I+II	5.91 (2.21–15.8)	<0.001	2.14 (0.40–11.4)	0.374
Postoperative radiation therapy (ref: no)	1.36 (0.54–3.42)	0.510
Postoperative ADT (ref: no)	2.42 (1.08–5.41)	0.032	1.58 (0.65–3.89)	0.315
Postoperative biochemical recurrence (ref: no)	8.84 (3.31–23.6)	<0.001

Adjusted-HRs were adjusted by those variables were significant in the univariable analyses and surgeons (n = 9). Functional status was excluded from the multivariable due to it was highly correlated with ASA. Postoperative biochemical recurrence was another outcome, therefore, it was also not included. PSA: prostate specific antigen; METs: Metabolic equivalents; ASA: American Society of Anesthesiologists; TNM: tumor-node-metastasis; ADT: androgen deprivation therapy.