Hepatitis B virus infection, diabetes mellitus, and their synergism for cholangiocarcinoma development: A case-control study in Korea

Table 2 Comparison of risk factors in patients with extrahepatic cholangiocarcinoma and matched controls n (%)

Variable	ECC patient (n = 193)	Control (n = 386)	Univariable analysis		Multivariable analysis
			OR (95%CI)	P value	AOR (95%CI)	P value
Cigarette smoking	53 (27.5)	91 (23.6)	1.32 (0.83-2.10)	0.240	-	-
< 20 pack-years	20 (10.4)	30 (7.8)	1.51 (0.79-2.87)	0.212	-	-
≥ 20 pack-years	33 (17.1)	61 (15.8)	1.23 (0.73-2.08)	0.444	-	-
Heavy alcohol consumption	18 (9.3)	24 (6.2)	1.62 (0.83-3.17)	0.161	-	-
Obesity	42 (21.8)	90 (23.3)	0.91 (0.59-1.40)	0.658	-	-
Cholecystolithiasis	33 (17.1)	28 (7.3)	2.49 (1.48-4.20)	0.001	2.01 (1.12-3.58)	0.019
Choledocholithiasis	24 (12.4)	2 (0.5)	24.00 (5.67-101.55)	< 0.001	18.08 (4.18-78.19)	< 0.001
Hepatolithiasis	9 (4.7)	1 (0.3)	18.00 (2.28-142.08)	0.006	14.87 (1.79-123.74)	0.013
Cholecystectomy	13 (6.7)	19 (4.9)	1.38 (0.67-2.84)	0.376	-	-
Ulcerative colitis	2 (1.0)	1 (0.3)	4.00 (0.36-44.11)	0.258	-	-
Alcoholic liver disease	7 (3.6)	13 (3.4)	1.08 (0.42-2.78)	0.871	-	-
Thyroid disease	5 (2.6)	15 (3.9)	0.64 (0.22-1.84)	0.408	-	-
Chronic pancreatitis	1 (0.5)	5 (1.3)	0.40 (0.05-3.42)	0.403	-	-
Hypertension	84 (43.5)	185 (47.9)	0.83 (0.58-1.19)	0.301	-	-
Diabetes mellitus	44 (22.8)	54 (14.0)	1.88 (1.19-2.98)	0.007	1.99 (1.22-3.27)	0.006
Without complications	27 (14.0)	38 (9.8)	1.64 (0.95-2.85)	0.077	1.78 (0.99-3.19)	0.055
With complications	17 (8.8)	16 (4.1)	2.43 (1.18-5.00)	0.016	2.48 (1.16-5.32)	0.020
HBV infection	9 (4.7)	9 (2.3)	2.10 (0.80-5.49)	0.131	-	-
HCV infection	6 (3.1)	10 (2.6)	1.20 (0.44-3.30)	0.724	-	-
Liver fluke infestation	3 (1.6)	2 (0.5)	3.00 (0.50-17.95)	0.229	-	-

HBV: Hepatitis B virus; HCV: Hepatitis C virus; ECC: Extrahepatic cholangiocarcinoma.