Cholecystectomy is independently associated with nonalcoholic fatty liver disease in an Asian population

Table 1 Baseline characteristics of control and nonalcoholic fatty liver disease subjects

	Control (P = 12275)	NAFLD (P = 5337)	P value
Age (yr)	47.4 ± 11.4	50.9 ± 10.5	< 0.001
Male	4839 (39.4)	3843 (72.0)	< 0.001
Waist circumference (cm)	80.3 ± 7.2	89.2 ± 6.9	< 0.001
Body mass index (kg/m2)	22.0 ± 2.6	25.4 ± 2.7	< 0.001
Systolic blood pressure (mmHg)	111.3 ± 14.3	119.3 ± 13.2	< 0.001
Diastolic blood pressure (mmHg)	71.4 ± 11.0	78.1 ± 10.5	< 0.001
Hypertension	1570 (12.8)	1451 (27.2)	< 0.001
Diabetes	373 (3.0)	498 (9.3)	< 0.001
Gamma-glutamyl transpeptidase (IU/L)	24.7 ± 31.3	42.7 ± 39.8	< 0.001
Alanine aminotransferase (IU/L)	19.1 ± 16.1	33.0 ± 23.5	< 0.001
Aspartate aminotransferase (IU/L)	20.7 ± 11.5	25.6 ± 12.8	< 0.001
Total cholesterol (mg/dL)	191.6 ± 32.9	200.5 ± 34.9	< 0.001
Triglycerides (mg/dL)	85.9 ± 50.0	144.8 ± 84.1	< 0.001
HDL-cholesterol (mg/dL)	57.6 ± 12.3	48.9 ± 9.6	< 0.001
Fasting glucose (mg/dL)	92.4 ± 12.7	102.5 ± 19.8	< 0.001
HbA1c (%)	5.7 ± 0.4	6.0 ± 0.7	< 0.001
Fasting insulin, μIU/mL (n = 8622)	5.8 ± 3.4	9.6 ± 5.5	< 0.001
HOMA-IR index (n = 8622)	1.4 ± 1.0	2.5 ± 1.6	< 0.001
Gallstones	421 (3.4)	292 (5.5)	< 0.001
Cholecystectomy	207 (1.7)	149 (2.8)	< 0.001
Gallstone disease	628 (5.1)	441 (8.3)	< 0.001
Smoking
Never-smoker	8300 (67.6)	2365 (44.3)	< 0.001
Current smoker	1419 (11.6)	1114 (20.9)
Ex-smoker	2556 (20.8)	1858 (34.8)
Regular physical activity	8112 (66.1)	3496 (65.5)	0.455

Data are presented as the mean ± SD or n (%). NAFLD: Nonalcoholic fatty liver disease; IR: Insulin resistance.