The safety of endoscopic sphincterotomy in patients receiving antiplatelet agents: a case-control study.

OBJECTIVE: To determine whether antiplatelet agents are associated with endoscopic sphincterotomy-related haemorrhage as few well-controlled data exist on this controversial issue.
METHODS: A case-control study in a tertiary care setting included cases with bleeding following endoscopic sphincterotomy, matched with 2-3 controls selected according to age +/- 15 years, sex, and procedural date+/- 2 years. Cases and controls were compared for possible risk factors of postendoscopic sphincterotomy bleeding (presence of a coagulopathy and cholangitis). The main outcome measurement was the association between the use of antiplatelet medications and postendoscopic sphincterotomy bleeding after adjustment for possible confounding.
RESULTS: The 40 cases [mean age 68 +/- 17 (s.d.) years, 50% female] and 86 controls [68 +/- 16 years, 50% female] were comparable except for differences noted in International Normalized Ratio (INR) (>2 in four cases vs. two controls), and pre-endoscopic sphincterotomy cholangitis (45% vs. 20%). Amongst cases, 13% were on aspirin and 3% on clopidogrel; 17% of controls took aspirin, and 4% a non-steroidal anti-inflammatory drug. 53% of cases bled immediately; the remainder haemorrhaged at 2 +/- 3 days. After adjustment for an elevated INR and cholangitis, exposure to antiplatelet agents was not significantly associated with procedure-related bleeding (odds ratio = 0.41, 95% CI [ 0.13; 1.31]).
CONCLUSION: This case-control study provides controlled data suggesting that antiplatelet agents do not significantly increase the risk of clinically-important bleeding related to endoscopic sphincterotomy. The low prevalences of non-steroidal anti-inflammatory drugs and clopidogrel use limit any definite conclusion on their elective use before endoscopic sphincterotomy.