WASHINGTON — Large polyp size and the use of anticoagulants significantly raised the risk of delayed postpolypectomy hemorrhage, but aspirin and a history of hypertension did not, according to findings presented at the annual Digestive Disease Week.
The results are in contrast to studies finding that hypertension, polyp location, and sessile polyps were risk factors for delayed bleeding, wrote Dr. Nadim Salfiti and coinvestigators at the University of Minnesota, Minneapolis.
In the case-control, retrospective chart review, the investigators analyzed 41 cases of postpolypectomy bleeding and 132 control cases at the Minneapolis VA Medical Center from 1999 to 2006. The mean age of the 41 case patients was 64 years, all were male, and most were white.
Four a priori risk factors were analyzed for correlation with bleed risk: heparin or warfarin use within 1 week post polypectomy; at least one aspirin dose taken between 1 week before and 1 week after polypectomy; hypertension, defined as systolic pressure greater than 140 mm Hg, or diastolic pressure greater than 90 mm Hg, or the use of antihypertensive medication; and polyp diameter.
The mean polyp size for cases was 10.5 mm, compared with 6.7 mm for controls, a statistically significant difference; a total of 37% of cases and 11% of controls had a polyp size greater than 1 cm. Even more significant was the use of heparin or warfarin within 1 week after polypectomy in 34% of the patients with hemorrhage, versus 9% of controls.
In contrast, at least one dose of aspirin was administered to roughly 40% of both cases and controls within the time period from 1 week before to 1 week after polypectomy, and slightly more than 60% of both cases and controls were hypertensive.
In a post hoc analysis, the researchers also tested to see whether diabetes, lung disease, coronary artery disease, or polyp type (sessile versus pedunculated) were related to postprocedure hemorrhage. Diabetes was present in 44% of cases and 24% of controls, and lung disease was identified in 34% of cases versus 19% of controls; both conditions were found to be moderately significant risk factors. Coronary artery disease was present in 59% of cases and 32% of controls, another statistically significant difference. However, after adjustment for the use of anticoagulants, all three conditions lost some significance. Polyp type was not a significant factor.
“This is the first study evaluating the risk of [using] anticoagulant medications after polypectomy,” Dr. Salfiti said in an interview. “These results need to be confirmed in prospective studies, but they do provide some information that could facilitate the decision regarding the timing of resuming anticoagulation.” Dr. Salfiti cautioned, however, that each patient should be evaluated individually. The risks of postpolypectomy bleeding versus the risk of a thromboembolic event need to be assessed.