Risk of upper gastrointestinal bleeding in patients taking low-dose aspirin for the prevention of cardiovascular diseases

Background: Most patients with vascular-occlusive diseases benefit from low-dose aspirin (75-325 mg/day). However, they have an increased risk of upper gastrointestinal bleeding (UGIB). Aims: To analyse the incidence and factors influencing the occurrence of UGIB in patients taking low-dose aspirin for the prevention of cardiovascular diseases outside clinical trials. Methods: We studied 903 consecutive patients discharged on low-dose aspirin from the Cardiology Department of a general hospital. Data were collected from medical charts and structured telephone interviews. Results: Forty-one patients (4.5%) presented with UGIB requiring hospitalization during follow-up (45 +/- 22 months). The incidence of UGIB was uniform during follow-up (1.2 UGIB per 100 patient years). Multivariate analysis showed that a history of peptic ulcer or UGIB [risk ratio: 3.1, 95% CI: (1.5-6.5)] and aspirin dose (per 100 mg/day) [1.8 (1.5-2.9)] was associated with higher risk of UGIB. On the other hand, antisecretory [0.22 (0.07-0.75)] and nitrovasodilator drugs [0.73 (0.55-0.96)] were associated with a decreased risk. Conclusions: Cardiovascular patients on long-term low-dose aspirin have a stable risk of major UGIB, which is higher than published controlled clinical trials. Antisecretory and nitrovasodilator drugs protect from UGIB, whereas previous peptic ulcer or UGIB and higher doses of aspirin increase the risk.