P0274 - Colonoscopy-Related Adverse Events in Patients With Abnormal Stool-Based Tests: A Systematic Review of Literature and Meta-Analysis of Outcomes

Saurabh Chandan, MD¹, Antonio Facciorusso, MD, PhD², Pradeep Yarra, MD³, Shahab R. Khan, MBBS⁴, Daryl Ramai, MD⁵, Babu Mohan, MD⁶, Mohammad Bilal, MD⁷, Aasma Shaukat, MD^7
1Creighton University School of Medicine, Omaha, NE; ²University of Foggia, Foggia, Puglia, Italy; ³University of Kentucky, Lexington, KY; ⁴Brigham & Women's Hospital, Harvard Medical School, Boston, MA; ⁵Brooklyn Hospital Center, Brooklyn, NY; ⁶University of Utah School of Medicine, Salt Lake City, UT; ⁷Minneapolis VA Health Care System, Minneapolis, MN

Introduction: Colorectal cancer (CRC) screening programs based on the fecal immunochemical test (FIT) and guaiac-based fecal occult blood (gFOBT) are associated with a substantial reduction in CRC incidence and mortality. The US Preventative Services Task Force (USPSTF) now recommends screening for colorectal cancer in adults aged 45 to 49 years with high sensitivity gFOBT or FIT every year. We conducted a systematic review and comprehensive meta-analysis to evaluate colonoscopy related adverse events in individuals with a positive FIT or gFOBT.

Methods: A systematic and detailed search was run in January 2021 with the assistance of a medical librarian for studies reporting on colonoscopy related adverse events as part of organized colorectal cancer screening programs. Meta-analysis was performed using random-effects model and results were expressed in terms of pooled proportions along with relevant 95% confidence intervals (CI).

Results: A total of 771,730 colonoscopies were performed in patients undergoing CRC screening using either gFOBT or FIT across 31 studies. Overall pooled incidence of severe adverse events (those requiring hospitalization and/or surgical intervention) in the entire patient cohort was 0.4% (CI 0.2—0.6); I²=38.76%. In patients with abnormal gFOBT, the incidence was 0.2% (CI 0.1-0.3); I²=24.6% and in those with a positive FIT, it was 0.4% (CI 0.2-0.7); I²=48.89%.

Overall pooled incidence of perforation events was 0.1% (CI 0.1-0.2); I²=22.84%. In patients with abnormal gFOBT, the incidence was 0.1% (CI 0.1-0.1); I²=28.15% and in patients with a positive FIT, it was 0.1% (CI 0.1-0.2); I²=46.38%. Overall pooled incidence of bleeding was 0.3% (CI 0.2-0.4); I²=35.58%. In patients with abnormal gFOBT, the incidence was 0.3% (CI 0.1-0.4); I²=31.94% and in patients with a positive FIT, it was 0.3% (CI 0.2-0.5); I²=48.96%. Overall pooled incidence of death was 0.0% (CI 0.00- 0.00); I²=33.21% . In patients with abnormal gFOBT, the incidence was 0.0% (CI 0.00- 0.00); I2= 0% and in patients with a positive FIT, it was 0.0% (CI 0.00-0.00); I²=22.56%. Pooled incidence of post polypectomy syndrome in gFOBT and FIT cohort patients undergoing therapeutic colonoscopy was 0.1% (CI 0.0-0.1); I²=42% and 0.1% (CI 0.0-0.2); I²=33% respectively.

Discussion: Our analysis shows that in colonoscopies performed following abnormal stool-based testing, the overall risk of severe adverse events, perforation, bleeding, and death is minimal. These risks parallel those of routine screening colonoscopy.


Figure: Overall Severe Adverse Events

Outcome	Overall
Severe Adverse Events	0.4% (CI 0.2—0.6); I2=38.76%
Perforation	0.1% (CI 0.1-0.2); I2= 22.84%
Bleeding	0.3% (CI 0.2-0.4); I2= 35.58%
Death	0.0% (CI 0.00-0.00); I2= 33.21%
	FOBT Cohort	FIT Cohort
Severe Adverse Events	0.2% (CI 0.1-0.3); I2= 24.6%	0.4% (CI 0.2-0.7); I2= 48.89%
Perforation	0.1% (CI 0.1-0.1); I2= 28.15%	0.1% (CI 0.1-0.2); I2= 46.38%
Bleeding	0.3% (CI 0.1-0.4); I2= 31.94%	0.3% (CI 0.2-0.5); I2= 48.96%
Death	0.0% (CI 0.0-0.0); I2= 0%	0.0% (CI 0.0-0.0); I2= 22.56%
Diagnostic Colonoscopy	FOBT Cohort	FIT Cohort
Perforation	0.0% (CI 0.0-0.0); I2= 15%	0.0% (CI 0.0-0.1); I2= 21%
Bleeding	0.0% (CI 0.0-0.0); I2= 15%	0.3% (CI 0.1-0.6); I2= 18%
Therapeutic Colonoscopy	FOBT Cohort	FIT Cohort
Perforation	0.2% (CI 0.1-0.2); I2= 34%	0.1% (CI 0.0-0.2); I2= 22%
Bleeding	0.4% (CI 0.1-0.6); I2= 30%	0.7% (CI 0.2-1.1); I2= 25%
Post-polypectomy Syndrome	0.1% (CI 0.0-0.1); I2=42%	0.1% (CI 0.0-0.2); I2=33%

Table: Summary of pooled outcomes


Disclosures:
Saurabh Chandan indicated no relevant financial relationships.
Antonio Facciorusso indicated no relevant financial relationships.
Pradeep Yarra indicated no relevant financial relationships.
Shahab Khan indicated no relevant financial relationships.
Daryl Ramai indicated no relevant financial relationships.
Babu Mohan indicated no relevant financial relationships.
Mohammad Bilal indicated no relevant financial relationships.
Aasma Shaukat indicated no relevant financial relationships.


Saurabh Chandan, MD¹, Antonio Facciorusso, MD, PhD², Pradeep Yarra, MD³, Shahab R. Khan, MBBS⁴, Daryl Ramai, MD⁵, Babu Mohan, MD⁶, Mohammad Bilal, MD⁷, Aasma Shaukat, MD⁷. P0274 - Colonoscopy-Related Adverse Events in Patients With Abnormal Stool-Based Tests: A Systematic Review of Literature and Meta-Analysis of Outcomes, ACG 2021 Annual Scientific Meeting Abstracts. Las Vegas, Nevada: American College of Gastroenterology.