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

Table 1 Patient clinical characteristics, n (%)

Variable	All patients (n = 577)	Non-AL patients (n = 541)	AL patients (n = 36)	Statistical value	P value
Gender				χ2 = 6.189	0.013
Female	276 (47.8)	266 (49.2)	10 (27.8)
Male	301 (52.2)	275 (50.8)	26 (72.2)
Age (yr)	71.0 (10.0)	71.0 (10.0)	72.0 (8.5)	Z = -1.005	0.315
BMI (kg/m2)	22.81 ± 3.43	22.79 ± 3.44	23.16 ± 3.25	t = -0.627	0.531
Smoking				χ2 = 0.866	0.352
No	393 (68.1)	371 (68.6)	22 (61.1)
Yes	184 (31.9)	170 (31.4)	14 (38.9)
History of abdominal surgery				χ2 = 0.086	0.770
No	413 (71.6)	388 (71.7)	25 (69.4)
Yes	164 (28.4)	153 (28.3)	11 (30.6)
Nonsteroidal drug use				χ2 = 0.000	1.000
No	524 (90.8)	491 (90.8)	33 (91.7)
Yes	53 (9.2)	50 (9.2)	3 (8.3)
Lung disease				χ2 = 0.061	0.804
No	316 (54.8)	297 (54.9)	19 (52.8)
Yes	261 (45.2)	244 (45.1)	17 (47.2)
Hypertension				χ2 = 2.362	0.124
No	381 (66.0)	353 (65.3)	28 (77.8)
Yes	196 (34.0)	188 (34.7)	8 (22.2)
Diabetes mellitus				χ2 = 1.203	0.273
No	486 (84.2)	458 (84.7)	28 (77.8)
Yes	91 (15.8)	83 (15.3)	8 (22.2)
Neoadjuvant chemotherapy				-1	0.124
No	567 (98.3)	533 (98.5)	34 (94.4)
Yes	10 (1.7)	8 (1.5)	2 (5.6)
Tumor location				-1	0.422
Right hemicolon	276 (47.8)	261 (48.2)	15 (41.7)
Transverse colon	29 (5.0)	28 (5.2)	1 (2.8)
Left hemicolon	64 (11.1)	57 (10.5)	7 (19.4)
Sigmoid colon	208 (36.1)	195 (36.1)	13 (36.1)
ASA classification				χ2 = 1.389	0.499
1	9 (1.6)	9 (1.7)	0 (0.0)
2	429 (74.4)	404 (74.7)	25 (69.4)
3	139 (24.0)	128 (23.6)	11 (30.6)
Surgical approach				χ2 = 4.110	0.128
Open	171 (29.6)	155 (28.7)	16 (44.4)
Laparoscopic	354 (61.4)	337 (62.2)	17 (47.2)
Robotic	52 (9.0)	49 (9.1)	3 (8.4)
Anastomosis				χ2 = 0.055	0.973
End-to-end anastomosis	198 (34.3)	185 (34.2)	13 (36.1)
End-lateral anastomosis	248 (43.0)	233 (43.1)	15 (41.7)
Lateral anastomosis	131 (22.7)	123 (22.7)	8 (22.2)
Blood transfusion intraoperatively and within 2 d postoperatively				χ2 = 20.869	< 0.001
No	427 (74.0)	412 (76.2)	15 (41.7)
Yes	150 (26.0)	129 (23.8)	21 (58.3)
T stage				-1	0.444
1	36 (6.2)	36 (6.7)	0 (0.0)
2	60 (10.4)	57 (10.5)	3 (8.3)
3	371 (64.3)	346 (64.0)	25 (69.4)
4	110 (19.1)	102 (18.8)	8 (22.3)
N stage				χ2 = 7.778	0.020
0	355 (61.5)	340 (62.9)	15 (41.7)
1	138 (23.9)	127 (23.5)	11 (30.6)
2	84 (14.6)	74 (13.7)	9 (27.7)
Tumor diameter (cm)	4.0 (3.0)	4.0 (3.0)	4.75 (2.6)	Z = -0.660	0.509
CEA (ng/mL)	3.78 (5.99)	3.66 (5.82)	5.11 (10.02)	Z = -1.468	0.142
Preoperative hemoglobin (g/L)	119.0 (40.0)	119.0 (40.0)	118.5 (32.75)	Z = -0.476	0.634
Preoperative albumin (g/L)	38.23 ± 4.69	38.40 ± 4.69	35.68 ± 3.81	t = 4.076	< 0.001
Preoperative NLR	2.62 (1.93)	2.55 (1.91)	3.36 (1.70)	Z = -3.688	< 0.001
Preoperative PNI	45.58 ± 5.94	45.86 ± 5.95	41.41 ± 3.94	t = 6.325	< 0.001

¹Variables were tested using Fisher’s exact probability method with no statistical values.

AL: Anastomotic leakage; BMI: Body mass index; ASA: American Society of Anesthesiologists; CEA: Carcinoembryonic antigen; NLR: Neutrophil-to-lymphocyte ratio; PNI: Prognostic nutritional index.