XbaI polymorphisms of apolipoprotein B gene: Another risk factor of gallstone formation after radical gastrectomy

Table 1 Demographic data of 186 gastric cancer patients who underwent gastrectomy with D2 dissection in the X⁺X^- and X^-X^- groups (mean ± SD) n (%)

	X+X- group	X-X- group	P value
	(n = 24)	(n = 162)
Age (yr)	52.4 ± 5.1	56.8 ± 7.4	0.998
Gender
Male	16 (66.7)	110 (67.9)	0.904
Female	8 (33.3)	52 (32.1)
BMI (kg/m2)	22.0 ± 1.2	21.7 ± 1.6	0.379
TNM stage1
IA	1 (4.2)	7 (4.3)	0.996
IB	4 (16.7)	31 (19.1)
II	8 (33.3)	52 (32.1)
IIIA	8 (33.3)	49 (30.3)
IIIB	3 (12.5)	23 (14.2)
Type of gastrectomy
Proximal gastrectomy	1 (4.2)	6 (3.7)	0.820
Distal gastrectomy	20 (83.3)	142 (87.7)
Total gastrectomy	3 (12.5)	14 (8.6)
Type of reconstruction
Without duodenal exclusion	14 (58.3)	96 (59.3)	0.991
With duodenal exclusion	10 (41.7)	66 (40.7)
Gallbladders motility after surgery
Normal	10 (41.7)	62 (38.3)	0.750
Abnormal	14 (58.3)	100 (61.7)

¹According to the Classification of IUCC. BMI: Body mass index.

Table 2 Gallstone formation after radical gastrectomy

	X+X- group	X-X- group	P value
	(n = 13)	(n = 15)
Incidence of gallstone	54.2% (13/24)	9.3% (15/162)	< 0.001
Time period from gastrectomy to detection of the gallstones (mo)	16.4 ± 8.4	21.7 ± 7.4	0.085
Gallbladders motility
GBEF before surgery	50.9% ± 12.5%	51.3% ± 10.3%	0.863
GBEF after surgery	30.3% ± 20.1%	29.6% ± 19.1%	0.868
Follow-up period after	28.3 ± 1.1	28.6 ± 1.2	0.249
gastrectomy (mo)

n: Number of patients with gallstone; GBEF: Gallbladder emptying fraction.

Table 3 Association of XbaI genotypes with gallstone after gastrectomy, stratified by gallbladder motility status

	Normal gallbladder motility1		Abnormal gallbladder motility1		Pinteraction
	Gallstone (+)	Gallstone (-)	Gallstone (+)	Gallstone (-)
X+X- group	3	7	10	4	0.701
X-X- group	1	61	14	86

¹According to the GBEF (gallbladder emptying fraction), estimated by logistic regression analysis.

Table 4 Serum levels of TC, LDL and APOB in X⁺X^- and X^-X^- groups (mean ± SD)

	X+X- group	X-X- group	P value
	(n = 24)	(n = 162)
Total cholesterol (mmol/L)
Before surgery	4.02 ± 1.12	3.48 ± 0.88	0.004
After surgery	3.88 ± 1.09	3.40 ± 0.86	0.008
Low-density lipoprotein (mmol/L)
Before surgery	2.21 ± 0.96	1.89 ± 0.84	0.042
After surgery	2.09 ± 0.95	1.72 ± 0.85	0.029
Apolipoprotein B (μg/L)
Before surgery	0.73 ± 0.15	0.70 ± 0.12	0.142
After surgery	0.72 ± 0.14	0.68 ± 0.12	0.072

TC: Total cholesterol; LDL: Low-density lipoprotein; APOB: Apolipoprotein B.