Clinical characteristics of colorectal polyps in patients with non-alcoholic fatty liver disease in high altitude areas

Table 1 Comparison of gender and age between two groups of non-alcoholic fatty liver disease patients, n (%)

	Qinghai NAFLD group (n = 585)	Tianjin NAFLD group (n = 91)	P value
Sex			0.153
Male	416 (71.1)	58 (63.7)
Female	169 (28.9)	33 (36.3)
Age
Youth	67 (11.5)	19 (20.9)	< 0.01
Middle age	326 (55.7)	47 (51.6)	0.467
Old age	192 (32.8)	25 (27.5)	0.309

NAFLD: Non-alcoholic fatty liver disease.

Table 2 General analysis of two groups of non-alcoholic fatty liver disease patients, n (%)

	Qinghai NAFLD group (n = 585)	Tianjin NAFLD group (n = 91)	P value
BMI	25.4 (23.7, 27.4)	27.48 (24.65, 29.07)	< 0.001
Drinking history	151 (25.8)	33 (36.3)	0.037
Smoking history	178 (30.4)	27 (29.7)	0.884
Hypertension disease	162 (27.7)	35 (38.5)	0.035
Diabetes	95 (16.2)	17 (18.7)	0.56
Coronary heart disease	19 (3.4)	6 (6.8)	0.08

NAFLD: Non-alcoholic fatty liver disease; BMI: Body mass index.

Table 3 Analysis of biochemical results for two groups of patients

	Qinghai NAFLD group (n = 585)	Tianjin NAFLD group (n = 91)	P value
ALT	27 (19, 41)	30.9 (16.9, 59.4)	0.462
AST	23 (19, 29)	26.4 (19.4, 43.1)	0.022
GGT	30 (21, 44)	46.6 (25.2, 83)	< 0.001
ALP	81 (70, 96.25)	72.7 (60.3, 92.3)	0.098
ALB	44 (40.075, 46.5)	44.6 (42.8, 46.8)	0.348
TBIL	17.55 (13.575, 25)	16.2 (13, 19.9)	< 0.002
DBIL	6 (4.4, 8)	2.2 (1.6, 2.7)	< 0.001
IBIL	11.6 (8.975, 16.8)	14 (10.4, 17.1)	0.061
Glu	5.31 (4.71, 6.25)	5.92 (5.42, 6.58)	< 0.001
TG	1.95 (1.39, 2.79)	1.61 (1.23, 2.38)	< 0.001
TC	4.725 (4.04, 5.27)	5.69 (5.05, 6.24)	< 0.001
TBA	3.245 (1.975, 5.513)	2.3 (1.4, 5.3)	0.044
BUN	5.275 (4.34, 6.27)	5 (3.8, 6)	0.006
CRE	67.25 (57.4, 76.8)	63.4 (56.8, 71)	0.459
UA	362 (305, 427.25)	354.1 (308.6, 457.7)	0.503
HDL	1.01 (0.85, 1.18)	1.31 (1.2, 1.55)	< 0.001
LDL	2.86 (2.42, 3.29)	3.24 (2.88, 3.84)	< 0.001
WBC	6.3 (5.4, 7.4)	6.34 (4.83, 7.23)	0.835
RBC	5.3 (4.9, 5.7)	4.72 (4.42, 5.08)	< 0.001
HGB	163 (151, 176)	146 (132, 154)	< 0.001
PLT	193 (150, 226)	244 (203, 274)	< 0.001

NAFLD: Non-alcoholic fatty liver disease; ALT: Alanine aminotransferase; AST: Aspartate aminotransferase; GGT: Γ-glutamyl transpeptidase; ALP: Alkaline phosphatase; ALB: Albumin; TBIL: Total bilirubin; DBIL: Direct bilirubin; IBIL: Indirect bilirubin; GLU: Glucose; TG: Triglycerides; TC: Total cholesterol; TBA: Total bile acids; BUN: Blood urea nitrogen; CRE: Creatinine; UA: Uric acid; HDL: High-density lipoprotein; LDL: Low-density lipoprotein; WBC: White blood cell count; RBC: Red blood cell count; HGB: Hemoglobin; PLT: Platelet count.

Table 4 Analysis of tumor marker results for two groups of patients

	Qinghai NAFLD group (n = 585)	Tianjin NAFLD group (n = 91)	P value
AFP	2.245 (1.61, 3.05)	3.36 (2.64, 4.42)	< 0.001
CA19-9	8.705 (6.258, 14.11)	16.53 (8.26, 26.17)	< 0.001
CEA	1.735 (1.128, 2.75)	1.86 (1.1, 2.79)	0.172

NAFLD: Non-alcoholic fatty liver disease; AFP: Alpha-fetoprotein; CA19-9: Carbohydrate antigen 19-9; CEA: Carcinoembryonic antigen.

Table 5 Comparative analysis of the number, size, and location of polyps found during colonoscopy for two groups of patients, n (%)

	Qinghai NAFLD group (n = 585)	Tianjin NAFLD group (n = 91)	P value
Polyps number
Single	174 (31.9)	29 (33.3)	0.794
Multiple	371 (68.1)	58 (66.7)
Polyp size			0.001
≤ 0.5 cm	226 (41.7)	42 (63.6)	< 0.01
> 0.5 cm and ≤ 1 cm	247 (45.6)	24 (36.4)	0.155
> 1 cm and ≤ 2 cm	51 (9.4)	0 (0)	0.004
≥ 2 cm	18 (3.3)	0 (0)	0.243
Polyp location			< 0.001
Proximal colon	27 (4.9)	12 (14.5)	< 0.001
Distal colon	106 (19.4)	8 (9.6)	0.031
Proximal colon+ distal colon	30 (5.5)	3 (3.6)	0.474

NAFLD: Non-alcoholic fatty liver disease.

Table 6 Comparative analysis of polyp pathology between two groups of patients, n (%)

	Qinghai NAFLD group (n = 409)	Tianjin NAFLD group (n = 77)	P value
Adenomatous polyps	365 (89.2)	19 (24.7)	< 0.001
Tubular adenomas, low-grade	345 (84.4)	16 (20.8)	< 0.001
Tubular adenomas, high-grade	3 (0.7)	3 (3.9)	0.021
Villous adenomas, low-grade	0 (0)	0 (0)	1
Villous adenomas, high-grade	0 (0)	0 (0)	1
Tubulovillous adenomas, low-grade	14 (3.4)	0 (0)	0.14
Tubulovillous adenomas, high-grade	3 (0.7)	0 (0)	1
Mixed hyperplastic-adenomatous polyps	2 (0.5)	13 (16.9)	< 0.001
Mixed hyperplastic-adenomas, low-grade	2 (0.5)	13 (16.9)	< 0.001
Mixed hyperplastic-adenomas, high-grade	0 (0)	0 (0)	1
Hyperplastic polyps	41 (10)	45 (58.4)	< 0.001
Hamartomas	0 (0)	0 (0)	1
Inflammatory polyps	1 (0.2)	0 (0)	1

¹Due to the zero number of cases, there are cells in the contingency table with excessively low expected frequencies (< 5), which means the assumptions of the χ² test are not met. Therefore, a valid P value could not be obtained.

NAFLD: Non-alcoholic fatty liver disease.

Table 7 Univariable analyses of risk factors for adenomatous polyps occurrence in patients in Qinghai region

	OR	95%CI	P value
Sex	1.371	0.956-1.968	0.087
Age	0.993	0.978-1.009	0.416
Drinking history	1.039	0.712-1.516	0.844
Smoking history	0.728	0.510-1.039	0.080
Hypertension disease	0.655	0.455-0.944	0.023
Diabetes	0.722	0.464-1.123	0.148
Coronary heart disease	1.505	0.564-4.017	0.414
BMI	0.963	0.914-1.015	0.164
ALT	1.002	0.997-1.008	0.449
AST	1.002	0.993-1.011	0.673
GGT	1.000	0.997-1.003	0.860
ALP	1.001	0.994-1.008	0.755
ALB	0.992	0.957-1.028	0.648
TBIL	0.991	0.975-1.008	0.284
DBIL	0.983	0.948-1.019	0.355
IBIL	0.984	0.960-1.008	0.188
GLU	1.014	0.938-1.096	0.725
TG	1.048	0.928-1.183	0.452
TC	1.013	0.957-1.073	0.657
TBA	0.997	0.959-1.036	0.880
BUN	0.975	0.880-1.079	0.621
CRE	1.004	0.994-1.014	0.465
UA	1.001	0.999-1.002	0.528
HDL	0.816	0.462-1.441	0.484
LDL	1.100	0.857-1.411	0.454
WBC	1.093	1.017-1.174	0.015
RBC	0.880	0.686-1.128	0.313
HGB	0.997	0.989-1.005	0.479
PLT	1.000	0.997-1.003	0.980
PT	0.988	0.942-1.036	0.618
AFP	0.974	0.844-1.124	0.716
CA19-9	1.002	0.977-1.007	0.392
CEA	1.054	0.988-1.126	0.112

BMI: Body mass index; ALT: Alanine aminotransferase; AST: Aspartate aminotransferase; GGT: Γ-glutamyl transpeptidase; ALP: Alkaline phosphatase; ALB: Albumin; TBIL: Total bilirubin; DBIL: Direct bilirubin; IBIL: Indirect bilirubin; GLU: Glucose; TG: Triglycerides; TC: Total cholesterol; TBA: Total bile acids; BUN: Blood urea nitrogen; CRE: Creatinine; UA: Uric acid; HDL: High-density lipoprotein; LDL: Low-density lipoprotein; WBC: White blood cell count; RBC: Red blood cell count; HGB: Hemoglobin; PLT: Platelet count; PT: Prothrombin time; AFP: Alpha-fetoprotein; CA19-9: Carbohydrate antigen 19-9; CEA: Carcinoembryonic antigen.

Table 8 Multivariable analyses of risk factors for adenomatous polyps occurrence in patients in Qinghai region

	OR	95%CI	P value
Sex	1.693	1.131-2.536	0.011
Smoking history	0.604	0.406-0.897	0.013
Hypertension disease	0.683	0.471-0.991	0.045
WBC	1.091	1.015-1.173	0.018

WBC: White blood cell count.