CHICAGO – New data shine a light on the trade-offs involved in resuming low-dose aspirin therapy for secondary cardiovascular prevention following a lower gastrointestinal bleeding event.
Going back onto daily low-dose aspirin was associated with a 2.7-fold greater risk of recurrent lower GI bleeding than no use of aspirin during 5 years of follow-up. However, the risk of a major cardiovascular event – nonfatal myocardial infarction or stroke or death due to a vascular cause – was reduced by 38%. Moreover, the rate of death due to nonvascular causes was 3.2-fold lower among the aspirin-using group, Dr. Francis K.L. Chan reported at the annual Digestive Disease Week.
He presented a single-center retrospective cohort study involving 295 patients who developed endoscopically confirmed lower GI bleeding while on low-dose aspirin for secondary cardiovascular prevention. A total of 174 subjects in this observational study resumed aspirin and 121 did not.
The two groups were similar in terms of their cardiovascular risk profiles based upon conventional risk factors. However, the aspirin nonusers, with a mean age of 76 years, were on average 3 years older than those who resumed aspirin. The nonusers were also more likely to have had a severe index lower GI bleed requiring transfusion of more than 2 units of blood products, by a margin of 55%-40%. An upper GI bleeding source was excluded by endoscopy in all participants, noted Dr. Chan of the Chinese University of Hong Kong.
The 5-year cumulative incidence of recurrent lower GI bleeding was 18.9% among the aspirin users, compared with 6.9% in the nonusers. The incidence of a major cardiovascular event was 22.8% in the aspirin group versus 36.5% among aspirin nonusers. And the 5-year incidence of death due to nonvascular causes was 8.2% in the aspirin users, compared with 26.7% in nonusers.
The nature of the Hong Kong health care system is such that all outcomes of interest were reliably captured. Eighty-four percent of patients in the aspirin user group received prescriptions for aspirin during at least 75% of the follow-up period, while 87% of the nonuser group received aspirin during 10% or less of the study period.
Audience members praised Dr. Chan for providing "clear-cut" and "very significant" findings addressing the previously unanswered but clinically important question of the risks and benefits of aspirin resumption versus nonuse following a lower GI bleed occurring while on therapy.
The study was carried out with institutional funds. Dr. Chan is on speakers bureaus for AstraZeneca, Pfizer, Takeda, and Eisai.