Metformin Use and Survival in Patients with Advanced Extrahepatic Cholangiocarcinoma: A Single-Center Cohort Study in Fuyang, China

Table 1

Baseline characteristics of the study and control groups [ (%)].

Characteristic	Study group	Control group		value
	Sex [ (%)]
Male	70 (52.6)	331 (56.2)	0.559	0.455
Female	63 (47.4)	258 (43.8)
Age [ (%)]
<60	59 (44.4)	249 (42.3)	0.193	0.660
≥60	74 (45.6)	340 (57.7)
Smoking history [ (%)]
Yes	23 (17.3)	96 (16.3)	0.078	0.780
No	110 (82.7)	493 (83.7)
Drinking history [ (%)]
Yes	22 (16.5)	90 (15.3)	0.132	0.717
No	111 (83.5)	499 (84.7)
Diabetes [ (%)]
Yes	6 (4.5)	29 (4.9)	0.040	0.842
No	127 (95.5)	560 (95.1)
Hepatitis B or C history [ (%)]
Yes	6 (4.5)	20 (3.4)	0.389	0.533
No	127 (95.5)	569 (96.6)
Family history of tumor [ (%)]
Yes	0 (0.0)	4 (0.07)	—	1.000
No	133 (100.0)	585 (99.93)
Residence [ (%)]
Town	59 (44.4)	291 (49.4)	1.106	0.293
Countryside	74 (45.6)	298 (50.6)
Tumor location [ (%)]
Perihilar CCA	39 (29.3)	181 (30.7)	0.045	0.833
Distal CCA	94 (70.7)	456 (69.3)
Cholelithiasis [ (%)]
Yes	0 (0.0)	11 (1.9)	1.431	0.232
No	133 (100.0)	578 (98.1)
PSC or PBC [ (%)]
Yes	0 (0.0)	1 (0.02)	—	1.000
No	133 (100.0)	588 (99.98)
Jaundice [ (%)]
Yes	126 (94.7)	532 (90.3)	2.617	0.106
No	7 (5.3)	57 (9.7)
Ascites [ (%)]
Yes	1 (0.08)	20 (3.4)	1.831	0.176
No	132 (99.92)	569 (96.6)
Radiotherapy [ (%)]
Yes	1 (0.08)	9 (1.5)	0.079	0.779
No	132 (99.92)	580 (98.5)
Other drugs that may affect tumor [ (%)]
Yes	0 (0.0)	16 (2.7)	—	0.053
No	133 (100.0)	573 (97.3)
Drainage treatment [ (%)]
Yes	113 (85.0)	496 (84.2)	0.046	0.829
No	20 (15.0)	93 (15.8)

PSC: primary sclerosing cholangitis; PBC: primary biliary cholangitis. Aspirin, immune regulation, antitumor, and Chinese herbal medicine, etc. ERBD: endoscopic retrograde biliary drainage (ERBD); PTCD: percutaneous transhepatic cholangial drainage.