Pre-operative hypoalbuminemia is a major risk factor for postoperative complications following rectal cancer surgery

Table 1 Demographic data on non-hypoalbuminemic and hypoalbuminemic patients

	Non-hypoalbuminemic	Hypoalbuminemic	P value
	(n = 188)	(n = 56)
Age (yr)	61.4 ± 11.9	64.5 ± 13.5	0.100
Male	111 (59)	28 (50)	0.230
BMI (kg/m2)	23.2 ± 3.8	21.9 ± 3.4a	0.021
Tumor size (cm)	4.3 ± 1.7	5.5 ± 2.3b	< 0.001
TNM stage			0.310
I	48 (26)	8 (14)
II	43 (23)	14 (25)
III	94 (50)	34 (61)
IV	3 (1)	0 (0)
Type of anesthesia			0.860
GA alone	73 (39)	21 (38)
GA + EB	115 (61)	35 (62)

GA: General anesthesia; EB: Epidural block. Values were given as number (percentage) or mean ± SD.

^aP≤ 0.05,

^bP≤ 0.01 vs Non-hypoalbuminemic.

Table 2 The relationship between the clinical characteristics of the patients and the development of postoperative complications analyzed using a univariate model

Variables	Category	n	Complication rate, n (%)	P value
Age	≥ 60	102	26 (25.5)	0.880
	< 60	142	35 (24.6)
Gender	Male	139	38 (27.3)	0.330
	Female	105	23 (21.9)
Obesity	Yes	10	3 (30.0)	0.710
	No	234	58 (24.8)
ASA status	I	65	11 (16.9)	0.041
	II	162	42 (25.9)
	III	17	8 (47.1)a
Anemia	Yes	18	6 (33.3)	0.390
	No	226	55 (24.3)
Hypoalbuminemia	Yes	56	21 (37.5)	0.014
	No	188	40 (21.3)a
Neoadjuvant therapy	Yes	23	5 (21.7)	0.900
	No	221	56 (25.3)
Tumor size	≥ 5 cm	105	27 (25.7)	0.820
	< 5 cm	139	34 (24.4)
Rectal tumor location	Upper	56	14 (25.0)	0.430
	Middle	134	30 (22.3)
	Lower	54	17 (31.4)
Sphincter-saving	Yes	179	44 (24.6)	0.800
procedure	No	65	17 (26.2)
Operation time	> 4 h	87	24 (27.6)	0.490
	< 4 h	157	37 (23.6)
Blood transfusion	Yes	32	9 (28.1)	0.660
	No	212	52 (24.5)

^aP≤ 0.05.

Table 3 Univariate analysis of clinical outcomes (mean ± SD)

	Non-hypoalbuminemic	Hypoalbuminemic	P value
	(n = 188)	(n = 56)
Postoperative complication (%)	21.3	37.5a	0.014
Time to first bowel movement (h)	2.3 ± 1.4	2.7 ± 1.6	0.090
Time to first defecation (d)	4.5 ± 1.7	4.6 ± 2.5	0.730
Time to resumption of normal diet (d)	4.8 ± 2.7	5.4 ± 2.9	0.180
Length of hospital stay (d)	10.4 ± 8.0	13.0 ± 8.9a	0.034

^aP≤ 0.05.