Observational Study
Copyright ©The Author(s) 2015.
World J Gastroenterol. May 28, 2015; 21(20): 6287-6295
Published online May 28, 2015. doi: 10.3748/wjg.v21.i20.6287
Table 1 Baseline characteristics of control and nonalcoholic fatty liver disease subjects
Control (P = 12275)NAFLD (P = 5337)P value
Age (yr)47.4 ± 11.450.9 ± 10.5< 0.001
Male4839 (39.4)3843 (72.0)< 0.001
Waist circumference (cm)80.3 ± 7.289.2 ± 6.9< 0.001
Body mass index (kg/m2)22.0 ± 2.625.4 ± 2.7< 0.001
Systolic blood pressure (mmHg)111.3 ± 14.3119.3 ± 13.2< 0.001
Diastolic blood pressure (mmHg)71.4 ± 11.078.1 ± 10.5< 0.001
Hypertension1570 (12.8)1451 (27.2)< 0.001
Diabetes373 (3.0)498 (9.3)< 0.001
Gamma-glutamyl transpeptidase (IU/L)24.7 ± 31.342.7 ± 39.8< 0.001
Alanine aminotransferase (IU/L)19.1 ± 16.133.0 ± 23.5< 0.001
Aspartate aminotransferase (IU/L)20.7 ± 11.525.6 ± 12.8< 0.001
Total cholesterol (mg/dL)191.6 ± 32.9200.5 ± 34.9< 0.001
Triglycerides (mg/dL)85.9 ± 50.0144.8 ± 84.1< 0.001
HDL-cholesterol (mg/dL)57.6 ± 12.348.9 ± 9.6< 0.001
Fasting glucose (mg/dL)92.4 ± 12.7102.5 ± 19.8< 0.001
HbA1c (%)5.7 ± 0.46.0 ± 0.7< 0.001
Fasting insulin, μIU/mL (n = 8622)5.8 ± 3.49.6 ± 5.5< 0.001
HOMA-IR index (n = 8622)1.4 ± 1.02.5 ± 1.6< 0.001
Gallstones421 (3.4)292 (5.5)< 0.001
Cholecystectomy207 (1.7)149 (2.8)< 0.001
Gallstone disease628 (5.1)441 (8.3)< 0.001
Smoking
Never-smoker8300 (67.6)2365 (44.3)< 0.001
Current smoker1419 (11.6)1114 (20.9)
Ex-smoker2556 (20.8)1858 (34.8)
Regular physical activity8112 (66.1)3496 (65.5)0.455
Table 2 Baseline characteristics of the subjects according to gallstone disease status
Control (n = 16543)Gallstone disease (n = 1069)Gallstone disease (n = 1069)
Gallstones (n = 713)Cholecystectomy (n = 356)
Age (yr)48.1 ± 11.154.5 ± 11.4a53.8 ± 11.2b55.8 ± 11.5c
Male8122 (49.1)560 (52.4)a377 (52.9)b183 (51.4)
Waist circumference (cm)82.8 ± 8.286.4 ± 8.5a86.3 ± 8.2b86.3 ± 7.7c
Body mass index (kg/m2)23.0 ± 3.124.1 ± 3.2a24.0 ± 3.1b23.9 ± 2.9c
Systolic blood pressure (mmHg)113.5 ± 14.4116.3 ± 15.2a117.0 ± 15.0b118.4 ± 14.5c
Diastolic blood pressure (mmHg)73.3 ± 11.375.2 ± 11.4a75.2 ± 11.2b75.2 ± 10.6c
Hypertension2710 (16.4)311 (29.1)a205 (28.8)b106 (29.8)c
Diabetes771 (4.7)100 (9.4)a67 (9.4)b33 (9.3)c
Gamma-glutamyl transpeptidase (IU/L)29.8 ± 32.934.6 ± 48.8a35.7 ± 58.8b38.0 ± 75.0c
Alanine aminotransferase (IU/L)23.1 ± 19.825.9 ± 18.6a26.0 ± 17.9b26.1 ± 16.4c
Aspartate aminotransferase (IU/L)22.1 ± 12.223.2 ± 11.1a23.6 ± 10.7b24.5 ± 9.9c
Total cholesterol (mg/dL)194.4 ± 33.7193.4 ± 33.7192.5 ± 33.6190.6 ± 33.4c
Triglycerides (mg/dL)103.2 ± 68.0111.1 ± 62.3a112.9 ± 65.9b116.4 ± 72.5c
HDL-cholesterol (mg/dL)55.1 ± 12.253.2 ± 12.1a53.3 ± 12.2b53.7 ± 12.6c
Fasting glucose (mg/dL)95.2 ± 15.599.6 ± 20.4a99.6 ± 20.8b99.5 ± 17.0c
HbA1c (%)5.8 ± 0.55.9 ± 0.7a5.9 ± 0.6b6.0 ± 0.5c
Fasting insulin, μIU/mL (n = 8622)6.9 ± 4.48.3 ± 6.2a8.3 ± 6.0b8.3 ± 5.7c
HOMA- IR index (n = 8622)1.7 ± 1.32.1 ± 1.7a2.1 ± 1.7b2.2 ± 1.7c
NAFLD4896 (29.6)441 (41.3)a292 (41.0)b149 (41.9)c
Smoking
Never-smoker10042 (60.7)623 (58.3)a419 (58.8)204 (57.3)c
Current smoker2398 (14.5)135 (12.6)a95 (13.3)40 (11.2)c
Ex-smoker4103 (24.8)311 (29.1)a199 (27.9)112 (31.5)c
Regular physical activity10835 (65.5)773 (72.3)a521 (73.1)b252 (70.8)c
Table 3 Univariate and multivariate analyses for the presence of nonalcoholic fatty liver disease according to gallstone disease status
VariableUnivariate model
Age, sex-adjusted model
Multivariate model1
OR (95%CI)P valueOR (95%CI)P valueOR (95%CI)P value
Gallstone disease
Control (n = 16543)111
Gallstone disease (n = 1069)1.67 (1.47-1.90)< 0.0011.47 (1.28-1.68)< 0.0011.22 (1.04-1.43)0.016
Cholecystectomy
Control111
Cholecystectomy (n = 356)1.67 (1.35-2.07)< 0.0011.46 (1.16-1.83)0.0011.35 (1.03-1.77)0.028
Gallstones
Control111
Gallstones (n = 713)1.65 (1.42-1.92)< 0.0011.46 (1.24-1.72)< 0.0011.15 (0.95-1.39)0.153
Table 4 Comparison of characteristics between subjects who underwent fasting insulin testing and those who did not
Fasting insulin absent (n = 8990)Fasting insulin available (n = 8622)P value
Age (yr)45.8 ± 11.851.2 ± 9.9< 0.001
Male4808 (46.5)4748 (55.1)< 0.001
Waist circumference (cm)82.8 ± 8.383.3 ± 8.1< 0.001
Body mass index (kg/m2)23.0 ± 3.123.1 ± 3.00.167
Systolic blood pressure (mmHg)113.2 ± 14.2114.3 ± 14.6< 0.001
Diastolic blood pressure (mmHg)73.3 ± 11.373.9 ± 11.30.020
Hypertension1300 (14.5)1721 (20.0)< 0.001
Diabetes356 (4.0)515 (6.0)< 0.001
Gamma-glutamyl transpeptidase (IU/L)30.1 ± 30.730.3 ± 39.00.732
Alanine aminotransferase (IU/L)23.1 ± 19.423.5 ± 20.00.142
Aspartate aminotransferase (IU/L)21.8 ± 12.422.6 ± 11.8< 0.001
Total cholesterol (mg/dL)193.0 ± 33.3195.6 ± 34.1< 0.001
Triglycerides (mg/dL)105.0 ± 70.2102.5 ± 65.50.017
HDL-cholesterol (mg/dL)55.0 ± 12.055.0 ± 12.50.693
Fasting glucose (mg/dL)95.4 ± 14.995.6 ± 16.90.606
HbA1c (%)5.77 ± 0.515.84 ± 0.56< 0.001
NAFLD2619 (29.1)2718 (31.5)0.001
Gallstone336 (3.7)377 (4.4)0.033
Cholecystectomy160 (1.8)196 (2.3)0.020
Gallstone disease496 (5.5)573 (6.6)0.002
Smoking< 0.001
Never-smoker5300 (59.0)5365 (62.2)
Current smoker1440 (16.0)1093 (12.7)
Ex-smoker2250 (25.0)2164 (25.1)
Regular physical activity5559 (61.8)6049 (70.2)< 0.001
Table 5 Univariate and multivariate analyses for the presence of nonalcoholic fatty liver disease according to gallstone disease status in subjects in whom fasting insulin testing was performed
VariableUnivariate model
Age, sex-adjusted model
Multivariate model 11
Multivariate model 22
OR (95%CI)P valueOR (95%CI)P valueOR (95%CI)P valueOR (95%CI)P value
Gallstone disease
Control (n = 8049)1111
Gallstone disease (n = 573)1.67 (1.41-1.99)< 0.0011.51 (1.26-1.82)< 0.0011.27 (1.03-1.58)0.0291.25 (1.00-1.55)0.052
Cholecystectomy
Control1111
Cholecystectomy (n = 196)1.76 (1.32-2.35)< 0.0011.59 (1.17-2.16)0.0031.45 (1.01-2.07)0.0441.45 (1.01-2.08)0.045
Gallstones
Control1111
Gallstones (n = 377)1.63 (1.32-2.01)< 0.0011.48 (1.18-1.85)0.0011.18 (0.91-1.54)0.211.14 (0.87-1.50)0.336