Table 1 The characteristics of the included studies (Page 9; line 139)

Liu, 2022 [20]

Cross-sectional study, China, 331

Ultrasonography, non-invasive fibrosis score

N/A

The degree of fibrosis in MAFLD is closely related to the prevalence of colorectal adenomatous polyp and high-risk adenoma.

Age, sex, and BMI

9

Seo, 2021 [31]

Cross-sectional study, Korea, 1127

Ultrasonography, non-invasive fibrosis score

79.6, 33.7%-male; 31.3%-female

MAFLD with advanced fibrosis was associated with an increased risk of colorectal adenoma.

Sex, smoking, and visceral fat area

9

Chuan, 2020 [21]

Cross-sectional study, China, 78

Fibro Touch, Fibro Touch

67.9% (severe MAFLD group 73.1%, mild or moderate MAFLD group 65.4%), N/A

The prevalence of adenomas was similar when comparing patients with CAP≥295 dB/m vs. 240 dB/m ≤ CAP< 295 dB/m.

N/A

8

Blackett, 2020 [20]

Cross-sectional study, the United States, 123

Biopsy, biopsy

49.6, 50.8%-male; 30.7%-female

The prevalence of adenomas was similar when comparing patients with no NASH versus NASH.

Age, sex, endoscopist, hyperlipidemia, diabetes, obesity, and colonoscopy indication

9

Cho, 2019 [22]

Cohort study, Korea, 379

Biopsy, biopsy

N/A

The prevalence of adenomas and advanced neoplasia was similar when comparing patients with NAFL versus NASH.

N/A

6

Kim, 2019 [23]

Cross-sectional study, Korea, 2395

Ultrasonography, non-invasive fibrosis score

71.3%

MAFLD patients with advanced fibrosis had a significantly higher risk for colorectal adenomas than those without advanced fibrosis.

Age, sex, obesity, smoking, hypertension, DM, hyperlipidemia, and metabolic syndrome

9

Kim, 2018 [24]

Cohort study, Korea, 8721

Ultrasonography, non-invasive fibrosis score

71.1%, 85.7 per 100,000 person-years -male; 30.3 per 100,000 person-years -female

The severity of MAFLD was not related to colorectal cancer

Age, sex, smoking status, diabetes, hypertension, GGT, HDL cholesterol, LDL cholesterol, and triglycerides

8

Ahn, 2017 [32]

Cross-sectional study, Korea, 9501

Ultrasonography, non-invasive fibrosis score

N/A

When compared to MAFLD patients with mild liver disease, the ORs for advanced colorectal neoplasia were higher for those with advanced fibrosis.

Age, sex, BMI, smoking, alcohol, aspirin use, fasting plasma glucose, first-degree family history of colorectal cancer, serum lipids, systolic blood pressure, drugs

9

Piyachaturawat, 2016 [25]

Cross-sectional study, Thailand, 161

TE-CAP, TE-CAP

N/A

The prevalence of adenomas and advanced adenomas was similar when comparing patients with fatty liver grade Severe vs. Mild to moderate.

N/A

7

Lee, 2016 [26]

Cross-sectional study, Korea, 14,655

Ultrasonography, ultrasonography

86.3% (severe MAFLD group 93.9%, mild or moderate MAFLD group 86.3%), N/A

The prevalence of adenomas and advanced neoplasia was similar when comparing patients with fatty liver grade Severe vs. Mild to moderate.

N/A

8

Yang, 2014 [27]

Cross-sectional study, China, 74

Ultrasonography, ultrasonography

90.5% (severe or moderate MAFLD group 90.6%, mild MAFLD group 90.5%), N/A

The prevalence of adenomas was similar when comparing patients with fatty liver grade Moderate to severe vs. Mild

N/A

8

Tantau, 2014 [28]

Case-control study, Romania, 50

Liver biopsy or abdominal ultrasounds,

liver biopsy or abdominal ultrasounds

N/A

NASH is independently related to the prevalence

of colorectal adenomas.

Demographic and metabolic factors

7

Wong, 2011 [29]

Cross-sectional study, China, 135

Biopsy, biopsy

54.8%, N/A

NASH is independently related to the prevalence

of colorectal adenomas and advanced neoplasia.

Demographic and metabolic factors

9

Touzin, 2011 [33]

Cohort study, the United States, 94

Biopsy, biopsy

62.8% (NASH 65.5%, non-NASH 61.5%), N/A

The prevalence of adenomas was similar when comparing patients with NASH vs. Non-NASH.

N/A

6