Does aspirin (acetylsalicylic acid) need to be held before a colonoscopy?

Management of Aspirin Therapy Before Colonoscopy

Aspirin should be continued without interruption before colonoscopy procedures, including those involving polypectomy. 1

Guideline Recommendations

The British Society of Gastroenterology (BSG) and European Society of Gastrointestinal Endoscopy (ESGE) provide clear guidance on aspirin management before endoscopic procedures:

• For all endoscopic procedures, including colonoscopy, they strongly recommend continuing aspirin therapy without interruption 1
• This recommendation applies to both diagnostic colonoscopy and therapeutic procedures including polypectomy 1
• The recommendation is based on evidence that aspirin monotherapy is safe in colonoscopic polypectomy 1

Risk Assessment

Bleeding Risk

• Aspirin monotherapy has been found to be safe in colonoscopic polypectomy with minimal increased bleeding risk 1
• Studies specifically examining aspirin use during colonoscopy with polypectomy have demonstrated its safety 1
• The bleeding risk from continuing aspirin is typically manageable with endoscopic techniques if it occurs 1

Thrombotic Risk

• Discontinuing aspirin in patients taking it for secondary prevention is associated with a three-fold increased risk of cardiovascular or cerebrovascular events 1
• 70% of these thrombotic events occur within 7-10 days after aspirin interruption 1
• In an RCT of patients on low-dose aspirin for secondary prevention undergoing non-cardiac surgery, major cardiac events occurred in 1.8% of the aspirin group compared to 9% in the placebo group (p=0.02) 1

Special Considerations

Polypectomy

• Aspirin monotherapy is safe to continue during colonoscopy with polypectomy 1
• For large polyps (>2 cm) or endoscopic mucosal resection (EMR), the risk of post-polypectomy bleeding may be higher, but aspirin can still be continued in most cases 1

Dual Antiplatelet Therapy

• If a patient is on dual antiplatelet therapy (aspirin plus P2Y12 inhibitor like clopidogrel):
  • Continue aspirin for all procedures 1
  • For high-risk procedures, consider discontinuing the P2Y12 inhibitor 7 days before the procedure after consulting with a cardiologist 1

Primary vs. Secondary Prevention

• For patients on aspirin for primary prevention, continuing aspirin is still recommended, though the thrombotic risk from discontinuation is lower 1
• For patients on aspirin for secondary prevention (previous cardiovascular events), continuing aspirin is strongly recommended due to significant thrombotic risk 1

Current Practice Patterns

Despite clear guidelines, practice patterns vary significantly:

• A survey of U.S. endoscopy units found that only 43.5% recommended continuing aspirin before colonoscopy 2
• 32.5% recommended stopping aspirin, and 24% requested patients contact their physician 2
• Common reasons for recommending discontinuation included concern about bleeding after polypectomy (62%) and perceived minimal downside to stopping aspirin (38%) 2

Conclusion

The evidence strongly supports continuing aspirin therapy before colonoscopy, including procedures involving polypectomy. The risk of thrombotic events from aspirin discontinuation outweighs the minimal increased risk of bleeding, particularly for patients taking aspirin for secondary prevention.