Preoperative neutrophil-to-lymphocyte ratio predicts symptomatic anastomotic leakage in elderly colon cancer patients: Multicenter propensity score-matched analysis

Table 2 Comparison of clinical characteristics before and after propensity score matching, n (%)

Variable	Before propensity score matching				After propensity score matching
	NLR < 2.66 (n = 295)	NLR ≥ 2.66 (n = 282)	SMD	P value	NLR < 2.66 (n = 122)	NLR ≥ 2.66 (n = 122)	SMD	P value
Gender			0.237	0.005			0.131	0.305
Female	158 (53.6)	118 (41.8)			55 (45.1)	63 (51.6)
Male	137 (46.4)	164 (58.2)			67 (54.9)	59 (48.4)
Age (yr)	70.0 (9.0)	72.0 (9.0)	0.232	0.004	70.0 (9.8)	71.0 (7.8)	0.032	0.722
BMI (kg/m2)	23.20 ± 3.49	22.40 ± 3.31	0.241	0.005	22.51 ± 3.20	22.67 ± 3.08	0.052	0.689
Smoking			0.230	0.004			0.119	0.118
No	217 (73.6)	176 (62.4)			82 (67.2)	93 (76.2)
Yes	78 (26.4)	106 (37.6)			40 (32.8)	29 (23.8)
History of abdominal surgery			0.065	0.443			0.076	0.560
No	207 (70.2)	206 (73.1)			88 (72.1)	92 (75.4)
Yes	88 (29.8)	76 (26.9)			34 (27.9)	30 (24.6)
Nonsteroidal drug use			0.022	0.795			0.063	0.641
No	267 (90.5)	257 (91.1)			111 (91.0)	113 (92.6)
Yes	28 (9.5)	25 (8.9)			11 (9.0)	9 (7.4)
Lung disease			0.214	0.010			0.117	0.364
No	177 (60.0)	139 (49.3)			67 (54.9)	74 (60.7)
Yes	118 (40.0)	143 (50.7)			55 (45.1)	48 (39.3)
Hypertension			0.047	0.573			0.018	0.891
No	198 (67.1)	183 (64.9)			82 (67.2)	83 (68.0)
Yes	97 (32.9)	99 (35.1)			40 (32.8)	39 (32.0)
Diabetes mellitus			0.100	0.207			0.022	0.864
No	254 (86.1)	232 (82.3)			101 (82.8)	102 (83.6)
Yes	41 (13.9)	50 (17.7)			21 (17.2)	20 (16.4)
Neoadjuvant chemotherapy			0.128	0.376			0.065	1.000
No	288 (97.6)	279 (98.9)			119 (97.5)	120 (98.4)
Yes	7 (2.4)	3 (1.1)			3 (2.5)	2 (1.6)
Tumor location			0.210	< 0.001			0.045	0.211
Right hemicolon	126 (42.7)	150 (53.2)			59 (48.4)	59 (48.4)
Transverse colon	8 (2.7)	21 (7.5)			2 (1.6)	8 (6.6)
Left hemicolon	30 (10.2)	34 (12.1)			17 (13.9)	19 (15.5)
Sigmoid colon	131 (44.4)	77 (27.2)			44 (36.1)	36 (29.5)
ASA classification			0.118	0.147			0.096	0.272
1	6 (2.0)	3 (1.1)			0 (0.0)	3 (2.5)
2	227 (77.0)	202 (71.6)			98 (80.3)	93 (76.2)
3	62 (21.0)	77 (27.3)			24 (19.7)	26 (21.3)
Surgical approach			0.279	< 0.001			0.099	0.330
Open	65 (22.0)	106 (37.6)			37 (30.3)	36 (29.5)
Laparoscopic	201 (68.2)	153 (54.3)			76 (62.3)	70 (57.4)
Robotic	29 (9.8)	23 (8.1)			9 (7.4)	16 (13.1)
Anastomosis			0.194	0.078			0.091	0.786
End-to-end anastomosis	114 (38.6)	84 (29.8)			40 (32.8)	35 (28.7)
End-lateral anastomosis	117 (39.7)	131 (46.5)			52 (42.6)	55 (45.1)
Lateral anastomosis	64 (21.7)	67 (23.7)			30 (24.6)	32 (26.2)
Blood transfusion intraoperatively and within 2 d postoperatively			0.318	< 0.001			0.000	1.000
No	240 (81.3)	187 (66.3)			91 (74.6)	91 (74.6)
Yes	55 (18.7)	95 (33.7)			31 (25.4)	31 (25.4)
T stage			0.339	< 0.001			0.066	0.944
1	27 (9.2)	9 (3.2)			6 (4.9)	8 (6.6)
2	36 (12.2)	24 (8.5)			11 (9.0)	12 (9.8)
3	197 (66.8)	174 (61.7)			85 (69.7)	82 (67.2)
4	35 (11.8)	75 (26.6)			20 (16.4)	20 (16.4)
N stage			0.147	0.191			0.116	0.655
0	192 (65.1)	163 (57.8)			75 (61.5)	68 (55.7)
1	63 (21.4)	75 (26.6)			29 (23.8)	34 (27.9)
2	40 (13.5)	44 (15.6)			18 (14.7)	20 (16.4)
Tumor diameter (cm)	4.00 (2.00)	5.00 (2.50)	0.427	< 0.001	4.00 (3.0)	4.75 (3.0)	0.051	0.824
CEA (ng/mL)	3.33 (4.74)	4.32 (6.97)	0.107	0.008	3.52 (5.57)	4.21 (5.59)	0.118	0.560
Preoperative hemoglobin (g/L)	126.00 (39.00)	109.50 (37.00)	0.332	< 0.001	119.5 (43.5)	117.5 (43.5)	0.035	0.711
Preoperative albumin (g/L)	39.00 ± 4.16	37.42 ± 5.06	0.311	< 0.001	38.34 ± 4.29	38.29 ± 4.77	0.009	0.944
Preoperative PNI	48.02 ± 5.22	43.04 ± 5.58	0.892	< 0.001	45.31 ± 4.99	45.16 ± 5.26	0.030	0.812

SMD: Standardized mean difference; BMI: Body mass index; ASA: American Society of Anesthesiologists; CEA: Carcinoembryonic antigen; NLR: Neutrophil-to-lymphocyte ratio; PNI: Prognostic nutritional index.