Sex-influenced association of non-alcoholic fatty liver disease with colorectal adenomatous and hyperplastic polyps

Table 1 Demographic and clinical characteristics of the subjects according to colonoscopic findings n (%)

	Colonoscopic findings of 3686 subjects
Characteristic	Polyp-free	Colorectal polyps	P value vs Polyp-free	Adenomatous polyps	P value vs Polyp-free	Hyperplastic polyps	P value vs Polyp-free
	2501 (67.9)	1185 (32.1)		498 (13.5)		288 (7.8)
Male	1487 (59.5)	943 (79.6)	< 0.001	393 (83.0)	< 0.001	239 (77.9)	< 0.001
Age (yr)	45.47 ± 9.99	50.48 ± 9.96	< 0.001	51.77 ± 9.78	< 0.001	48.16 ± 9.09	< 0.001
Weight (kg)	64.27 ± 11.29	68.33 ± 11.04	< 0.001	67.58 ± 11.13	< 0.001	69.57 ± 11.01	< 0.001
Height (cm)	164.64 ± 7.71	166.59 ± 7.26	< 0.001	165.95 ± 7.47	0.001	167.46 ± 7.01	< 0.001
BMI (kg/m2)	23.62 ± 3.22	24.54 ± 3.10	< 0.001	24.45 ± 3.10	< 0.001	24.75 ± 3.13	< 0.001
SBP (mmHg)	124.43 ± 17.78	129.99 ± 18.34	< 0.001	130.57 ± 18.75	< 0.001	127.72 ± 17.94	0.003
DBP (mmHg)	73.48 ± 12.27	76.96 ± 12.11	< 0.001	77.19 ± 12.13	< 0.001	76.72 ± 12.26	< 0.001
FPG (mmol/L)	4.78 ± 1.13	5.01 ± 1.41	< 0.001	4.99 ± 1.39	0.001	4.93 ± 1.36	0.032
TG (mmol/L)	1.79 ± 1.71	2.01 ± 1.81	< 0.001	1.98 ± 2.04	0.032	2.05 ± 1.23	0.013
TC (mmol/L)	5.35 ± 1.12	5.44 ± 1.12	0.020	5.44 ± 1.21	0.093	5.53 ± 1.10	0.009
HDL-C (mmol/L)	1.32 ± 0.33	1.26 ± 0.30	< 0.001	1.28 ± 0.31	0.003	1.24 ± 0.28	< 0.001
LDL-C (mmol/L)	3.19 ± 0.86	3.27 ± 0.86	0.011	3.25 ± 0.84	0.154	3.36 ± 0.92	0.002
ALT (IU/L)	29.25 ± 29.65	32.23 ± 27.51	0.004	31.86 ± 22.61	0.065	32.85 ± 25.87	0.051
AST (IU/L)	27.24 ± 16.19	28.89 ± 17.63	0.007	28.75 ± 11.80	0.049	28.57 ± 13.43	0.184
NAFLD	488 (17.9)	291 (24.6)	< 0.001	122 (27.4)	0.002	79 (22.6)	0.001
MS	246 (10.1)	180 (15.6)	< 0.001	73 (15.5)	0.005	44 (16.4)	0.016
Smoking	662 (26.6)	373 (31.7)	0.002	151 (30.5)	0.087	101 (35.2)	0.004
Alcohol	854 (34.4)	445 (37.8)	0.042	191 (38.6)	0.078	118 (41.1)	0.028

BMI: Body mass index; SBP: Systolic blood pressure; DBP: Diastolic blood pressure; FPG: Fasting plasma glucose; TG: Triglyceride; TC: Total cholesterol; HDL-C: High density lipoprotein-cholesterol; LDL-C: Low density lipoprotein-cholesterol; ALT: Alanine aminotransferase; AST: Aspartate aminotransferase; NAFLD: Non-alcoholic fatty liver disease; MS: Metabolic syndrome.

Table 2 Demographic and clinical characteristics of 2430 males and 1256 females according to colonoscopic findings n (%)

Characteristic of males	Polyp-free	Colorectal polyps	P value vs Polyp-free	Adenomatous polyps	P value vs Polyp-free	Hyperplastic polyps	P value vs Polyp-free
Colonoscopic findings of 2430 males
	1487 (61.2)	943 (38.8)		393 (16.2)		239 (9.8)
Age (yr)	44.61 ± 9.91	50.18 ± 9.67	< 0.001	51.71 ± 9.54	< 0.001	47.56 ± 8.90	< 0.001
Weight (kg)	69.46 ± 10.18	70.88 ± 10.20	0.001	70.27 ± 10.12	0.164	71.47 ± 10.74	0.005
Height (cm)	169.13 ± 5.56	168.88 ± 5.80	0.305	168.28 ± 6.04	0.012	169.44 ± 5.72	0.427
BMI (kg/m2)	24.28 ± 3.22	24.81 ± 3.06	< 0.001	24.77 ± 3.03	0.006	24.85 ± 3.22	0.011
SBP (mmHg)	127.29 ± 16.24	130.47 ± 17.83	< 0.001	131.97 ± 18.29	< 0.001	127.82 ± 16.88	0.639
DBP (mmHg)	76.44 ± 11.75	78.14 ± 12.03	0.001	78.77 ± 11.93	0.001	77.57 ± 12.11	0.173
FPG (mmol/L)	4.86 ± 1.26	5.06 ± 1.49	0.001	5.04 ± 1.46	0.012	4.96 ± 1.42	0.233
TG (mmol/L)	2.14 ± 2.04	2.15 ± 1.95	0.920	2.16 ± 2.24	0.878	2.14 ± 1.24	0.987
TC (mmol/L)	5.42 ± 1.16	5.42 ± 1.12	0.954	5.45 ± 1.24	0.686	5.49 ± 1.08	0.374
HDL-C (mmol/L)	1.22 ± 0.28	1.22 ± 0.29	0.892	1.24 ± 0.30	0.244	1.21 ± 0.27	0.597
LDL-C (mmol/L)	3.26 ± 0.86	3.26 ± 0.84	0.829	3.24 ± 0.83	0.632	3.34 ± 0.90	0.221
ALT (IU/L)	34.71 ± 33.63	35.31 ± 29.49	0.657	35.54 ± 23.59	0.649	35.2 ± 27.26	0.834
AST (IU/L)	29.00 ± 17.83	30.22 ± 19.06	0.115	30.37 ± 12.31	0.155	29.32 ± 13.41	0.796
NAFLD	355 (23.9)	268 (28.4)	0.014	116 (29.5)	0.028	72 (30.1)	0.038
MS	194 (13.3)	156 (17.0)	0.018	64 (15.8)	0.123	37 (18.3)	0.334
Smoking	465 (31.4)	327 (34.9)	0.076	127 (32.4)	0.717	91 (38.2)	0.045
Alcohol	577 (39.0)	377 (40.3)	0.536	153 (39.0)	0.995	100 (42.0)	0.379
Colonoscopic findings of 1256 females
	1014 (80.7)	242 (19.3)		105 (8.4)		49 (3.9)
Age (yr)	46.73 ± 9.97	51.68 ± 10.96	< 0.001	51.99 ± 10.68	< 0.001	51.10 ± 9.50	0.003
Weight (kg)	56.62 ± 8.03	58.41 ± 8.27	0.002	57.34 ± 8.61	0.385	60.42 ± 7.01	0.001
Height (cm)	158.04 ± 5.32	157.62 ± 5.16	0.268	157.08 ± 5.46	0.080	157.89 ± 4.21	0.840
BMI (kg/m2)	22.66 ± 2.96	23.50 ± 3.05	< 0.001	23.21 ± 3.06	0.073	24.24 ± 2.66	< 0.001
SBP (mmHg)	120.23 ± 19.07	128.13 ± 20.13	< 0.001	125.21 ± 19.59	0.012	127.25 ± 22.56	0.013
DBP (mmHg)	69.12 ± 11.70	72.40 ± 11.31	< 0.001	71.19 ± 11.03	0.086	72.63 ± 12.27	0.041
FPG (mmol/L)	4.66 ± 0.90	4.80 ± 0.99	0.037	4.80 ± 1.07	0.147	4.80 ± 1.06	0.318
TG (mmol/L)	1.27 ± 0.80	1.46 ± 0.92	0.002	1.30 ± 0.66	0.716	1.65 ± 1.11	0.002
TC (mmol/L)	5.25 ± 1.05	5.52 ± 1.10	< 0.001	5.43 ± 1.09	0.088	5.72 ± 1.17	0.002
HDL-C (mmol/L)	1.48 ± 0.33	1.42 ± 0.31	0.008	1.43 ± 0.31	0.114	1.41 ± 0.28	0.123
LDL-C (mmol/L)	3.09 ± 0.85	3.33 ± 0.91	< 0.001	3.30 ± 0.87	0.017	3.45 ± 1.00	0.004
ALT (IU/L)	21.15 ± 19.93	20.13 ± 11.46	0.451	17.74 ± 9.29	3.000	21.76 ± 13.28	0.835
AST (IU/L)	24.64 ± 12.98	23.71 ± 8.56	0.286	22.62 ± 6.73	0.121	25.00 ± 13.10	0.848
NAFLD	93 (9.2)	23 (9.5)	0.873	6 (5.7)	0.160	7 (14.3)	0.324
MS	52 (5.3)	24 (10.2)	0.021	9 (8.8)	0.227	7 (14.3)	0.084
Smoking	197 (19.6)	46 (19.2)	0.884	24 (23.3)	0.369	10 (20.4)	0.887
Alcohol	277 (27.5)	68 (28.3)	0.804	38 (36.9)	0.063	18 (36.7)	0.201

BMI: Body mass index; SBP: Systolic blood pressure; DBP: Diastolic blood pressure; FPG: Fasting plasma glucose; TG: Triglyceride; TC: Total cholesterol; HDL-C: High density lipoprotein-cholesterol; LDL-C: Low density lipoprotein-cholesterol; ALT: Alanine aminotransferase; AST: Aspartate aminotransferase; NAFLD: Non-alcoholic fatty liver disease; MS: Metabolic syndrome.

Table 3 Adjusted ORs and 95%CIs of clinical variables on the risk of colorectal polyps, adenomatous polyps and hyperplastic polyps based on multinomial logistic regression

Polyps	Model A	Model B	Model C
	OR (95%CI)	OR (95%CI)	OR (95%CI)
Colorectal polyps
NAFLD	1.49 (1.26-1.76)b	1.28 (1.07-1.52)a	1.26 (1.05-1.51)a
Gender		2.81 (2.37-3.34)b	2.76 (2.32-3.29)b
Age		1.06 (1.05-1.06)b	1.06 (1.05-1.06)b
Smoking		1.15 (0.98-1.35)	1.15 (0.97-1.38)
Alcohol			1.01 (0.86-1.20)
MS			1.12 (0.90-1.40)
Adenomatous polyps
NAFLD	1.49 (1.18-1.87)a	1.29 (1.02-1.64)a	1.28 (1.01-1.64)a
Gender		2.83 (2.22-3.61)b	2.78 (2.18-3.55)b
Age		1.07 (1.06-1.08)b	1.07 (1.06-1.08)b
Smoking		1.09 (0.88-1.36)	1.06 (0.84-1.35)
Alcohol			1.09 (0.87-1.37)
MS			1.02 (0.76-1.38)
Hyperplastic polyps
NAFLD	1.73 (1.31-2.29)b	1.40 (1.05-1.86)a	1.35 (1.01-1.82)a
Gender		3.23 (2.33-4.47)b	3.12 (2.25-4.33)b
Age		1.03 (1.02-1.05)b	1.03 (1.02-1.05)b
Smoking		1.30 (1.00-1.70)a	1.27 (0.95-1.70)
Alcohol			1.09 (0.82-1.44)
MS			1.13 (0.79-1.63)

Model A is univariate analysis; Model B is adjusted for gender, age and smoking; Model C is adjusted for gender, age, smoking, alcohol and MS.

^aP < 0.05;

^bP < 0.001. NAFLD: Non-alcoholic fatty liver disease; MS: Metabolic syndrome.

Table 4 Adjusted odds ratios and 95%CIs of clinical variables on the risk of colorectal polyps, adenomatous polyps and hyperplastic polyps according to different-sex groups based on multinomial logistic regression

Polyps	Model A		Model B		Model C
	Male	Female	Male	Female	Male	Female
	OR (95%CI)	OR (95%CI)	OR (95%CI)	OR (95%CI)	OR (95%CI)	OR (95%CI)
Colorectal polyps
NAFLD	1.27 (1.05-1.52)a	1.04 (0.64-1.68)	1.41 (1.16-1.71)a	0.80 (0.49-1.32)	1.40 (1.14-1.71)a	0.78 (0.47-1.28)
Age			1.06 (1.05-1.07)b	1.05 (1.03-1.06)b	1.06 (1.05-1.07)b	1.05 (1.03-1.06)b
Smoking			1.22 (1.02-1.46)a	0.95 (0.66-1.36)	1.23 (1.02-1.50)a	0.88 (0.57-1.36)
Alcohol					0.98 (0.81-1.19)	1.19 (0.81-1.74)
MS					1.07 (0.84-1.37)	1.37 (0.80-2.34)
Adenomatous polyps
NAFLD	1.34 (1.04-1.71)a	0.60 (0.26-1.41)	1.53 (1.19-1.98)a	0.45 (0.19-1.07)	1.53 (1.18-2.00)a	0.44 (0.18-1.04)
Age			1.08 (1.06-1.09)b	1.05 (1.03-1.07)b	1.08 (1.06-1.09)b	1.05 (1.03-1.07)b
Smoking			1.10 (0.86-1.40)	1.24 (0.76-2.02)	1.12 (0.85-1.46)	0.90 (0.50-1.61)
Alcohol					0.97 (0.75-1.25)	1.77 (1.06-2.96)a
MS					0.98 (0.71-1.36)	1.17 (0.53-2.56)
Hyperplastic polyps
NAFLD	1.38 (1.02-1.86)a	1.65 (0.72-3.78)	1.44 (1.06-1.95)a	1.30 (0.56-3.03)	1.42 (1.04-1.95)a	1.18 (0.50-2.78)
Age			1.04 (1.02-1.05)b	1.04 (1.01-1.07)a	1.04 (1.02-1.05)b	1.04 (1.01-1.07)a
Smoking			1.38 (1.03-1.83)a	1.01 (0.49-2.06)	1.38 (1.01-1.88)a	0.71 (0.31-1.65)
Alcohol					1.01 (0.74-1.36)	1.85 (0.92-3.72)
MS					1.02 (0.69-1.52)	2.01 (0.81-4.94)

Model A is univariate analysis; Model B is adjusted for age and smoking; Model C is adjusted for age, smoking, alcohol and MS.

^aP < 0.05,

^bP < 0.001. NAFLD: Non-alcoholic fatty liver disease; MS: Metabolic syndrome.

Table 5 Adjusted odds ratios and 95%CIs of non-alcoholic fatty liver disease for adenomatous polyps and hyperplastic polyps of the colon and rectum by morphological characteristics in males

	Adenomatous polyps		P value	Hyperplastic polyps		P value
	Cases	OR (95%CI)		Cases	OR (95%CI)
Number
Single	186	1.27 (0.88-1.82)	0.205	117	1.81 (1.19-2.74)	0.005
Multiple	207	1.82 (1.29-2.55)	0.001	121	1.13 (0.73-1.76)	0.583
Size
Small (< 1 cm)	332	1.44 (1.08-1.91)	0.013	229	1.45 (1.05-2.00)	0.023
Large (≥ 1 cm)	61	2.13 (1.21-3.76)	0.009	9	1.00 (0.20-5.07)	0.999
Location
Proximal lesions	129	1.15 (0.73-1.80)	0.539	38	2.62 (1.32-5.17)	0.006
Distal lesions	146	1.63 (1.11-2.39)	0.013	156	1.33 (0.91-1.95)	0.146
Bilateral lesions	118	1.89 (1.23-2.91)	0.004	44	1.05 (0.51-2.17)	0.894

ORs compared with non-alcoholic fatty liver disease and adjusted for age, smoking, alcohol and metabolic syndrome.