Impact of perioperative transfusion in patients undergoing resection of colorectal cancer liver metastases: A population-based study

Table 1 Characteristics of the study population (unweighted n = 2018, weighted n = 9991)

	Total	No transfusion	Perioperative transfusion	P-value1
	n = 2018	n = 1538	n = 480
Demographic data
Age
<70 yr	1532 (76.04)	1195 (77.88)	337 (70.12)	0.0004a
≥70 yr	486 (23.96)	343 (22.12)	143 (29.88)
Sex
Male	1112 (55.10)	870 (56.59)	242 (50.32)	0.01a
Female	903 (44.90)	665 (43.41)	238 (49.68)
Race
White	1251 (76.29)	955 (76.94)	296 (74.22)	0.10
Black	175 (10.53)	121 (9.63)	54 (13.32)
Hispanic	115 (7.07)	86 (7.04)	29 (7.16)
Asian/Pacific	55 (3.32)	40 (3.21)	15 (3.62)
Others	46 (2.80)	39 (3.16)	7 (1.68)
Household income
Q1	484 (24.34)	355 (23.59)	129 (26.90)	0.14
Q2	473 (23.79)	369 (24.34)	104 (22.06)
Q3	471 (23.93)	372 (24.89)	99 (20.87)
Q4	541 (27.93)	400 (27.22)	141 (30.16)
Type of admission
Elective	1676 (83.35)	1311 (85.59)	365 (76.12)	<0.0001a
Emergency	338 (16.65)	224 (14.41)	114 (23.88)
Insurance status
Medicare/Medicaid	877 (43.31)	628 (40.62)	249 (51.97)	<0.0001a
Private including HMO	1027 (51.05)	816 (53.25)	211 (43.95)
Self-pay/no charge/other	114 (5.65)	94 (6.13)	20 (4.07)
Clinical data
Hepatic precondition
No	1967 (97.41)	1494 (97.07)	473 (98.52)	0.24
Steatosis/fibrosis	44 (2.23)	38 (2.52)	6 (1.29)
Cirrhosis	7 (0.36)	6 (0.41)	1 (0.19)
Primary tumor site
Colon	1595 (79.04)	1194 (77.64)	401 (83.59)	0.003a
Rectum	423 (20.95)	344 (22.36)	79 (16.40)
Extent of liver resection
Partial hepatectomy	1541 (76.46)	1204 (78.39)	337 (70.19)	<0.0001a
Hepatic lobectomy	477 (23.54)	334 (21.60)	143 (29.81)
Laparoscopic procedure
No	1971 (97.64)	1498 (9737.)	473 (98.52)	0.15
Yes	47 (2.36)	40 (2.63)	7 (1.48)
Robotic-assisted
No	2010 (99..59)	14532 (99.59)	478 (99.56)	0.91
Yes	8 (0.41)	6 (0.40)	2 (0.43)
Comorbidity
Chronic anemia	422 (20.71)	247 (15.87)	175 (36.37)	<0.0001a
Congestive heart failure	59 (2.95)	35 (2.31)	24 (5.02)	0.002a
Chronic pulmonary disease	188 (9.26)	135 (8.72)	53 (11.02)	0.12
Diabetes	293 (14.32)	221 (14.16)	72 (14.84)	0.70
Hypertension	848 (41.82)	625 (40.43)	223 (46.32)	0.02a
Obesity	118 (5.85)	89 (5.80)	29 (6.02)	0.86
Renal failure	39 (1.89)	30 (1.936)	9 (1.79)	0.86
Hospital data
Hospital bed size
Small	212 (10.21)	162 (10.28)	50 (9.97)	0.007a
Medium	327 (16.58)	227 (15.15)	100 (21.12)
Large	1453 (73.22)	1125 (74.56)	328 (68.91)
Location of hospital
Rural	77 (3.71)	62 (3.89)	15 (3.14)	0.34
Urban	1915 (96.29)	1452 (96.10)	463 (96.87)
Teaching status of hospital
Non-teaching	419 (20.65)	284 (18.46)	135 (27.64)	<0.0001a
Teaching	1573 (79.35)	1230 (81.54)	343 (72.36)
Region of hospital
Northeast	437 (22.65)	351 (23.79)	86 (18.97)	0.11
Midwest	480 (23.71)	360 (23.27)	120 (25.11)
South	737 (35.65)	566 (35.99)	171 (34.53)
West	364 (17.98)	261 (16.94)	103 (21.39)

Data are presented as unweighted counts (weighted proportion). Percentages may not add up to 100% due to missing data. Q1: 0-25^th percentile; Q2: 26^th to 50^th percentile; Q3: 51^st to 75^th percentile; Q4: 76^th to 100^th percentile.

¹χ² test.

^aP < 0.05, non-transfusion group vs transfusion group.