Irritable bowel syndrome and colon cancer: A meta-analysis

Table 1 Characteristics of the included studies, mean ± SD

Ref.	Age	CRC diagnosis	IBS diagnosis	Population description	Number of participants	Study design	Country
Akhtar et al[14], 2006	Range 19-91	Biopsy	Rome I/II, Manning criteria	Not clearly specified	169 cases, 186, and controls	Cross-sectional	United States
Canavan et al[15], 2014	42.9	GP diagnosis	GP diagnosis	Inclusion: Age 18-75; exclusion: CD, IBD, CRC	112854 cases, and 546903	Cohort	United Kingdom
Chang et al[10], 2015	60.9 ± 12.2	IFOBT, colonoscopy, and national cancer registry	ICD-9: 564.0, 564.1	Excluded patients with a colonic neoplasia or IBS diagnosis before screening	91160 cases, and 39224 controls	Cohort	Taiwan
Chey et al[16], 2010	41.1 ± 12.9	NA	Rome II criteria	Excluded IBS-C, alarm features, pregnancy, family history of CRC, prior GI disease/surgery	466 cases, and 451 controls	Cross-sectional	United States
Gu et al[17], 2011	34.1 ± 7.8	Biopsy	Rome III criteria	Excluded alarm features, family history of CRC, onset > 50 years	3332 cases, and 1588 controls	Cross-sectional	China
Ejtehadi et al[5], 2023	37.8 ± 12.4	Biopsy	Rome IV criteria	IBS patients undergoing colonoscopy compared with controls	96 IBS patients, and 101 controls	Comparative cross-sectional	Iran
Hsiao et al[11], 2014	44.6 ± 19.7	ICD-9: 153, 154	ICD-9: 564.1	Excluded cancer and missing demographic data	527077 cases, and 1014793 controls	Cohort	Taiwan
Ishihara et al[18], 2012	Median 57.9	Biopsy	Rome III criteria	Excluded emergency cases with melena	198 cases, and 3831 controls	Cross-sectional	China
Staller et al[19], 2021	44.7 ± 17.0	SNOMED	ICD-9: 564B; ICD-10: K58	Colonoscopy with biopsy < 6 months from IBS diagnosis; exclusion of CD, MC, CRP, CRC	21778 cases, and 1679334 controls	Cross-sectional	Sweden

CRC: Colorectal cancer; IBS: Irritable bowel syndrome; GP: General practitioner; IFOBT: Immunochemical fecal occult blood test; NA: Not available; ICD: International Classification of Diseases; SNOMED: Systematized nomenclature of medicine; CD: Crohn’s disease; IBS-C: Irritable bowel syndrome with constipation; GI: Gastrointestinal; MC: Microscopic colitis; CRP: C-reactive protein.