WASHINGTON — Low-dose aspirin alone may be the most cost-effective antiplatelet therapy despite the risk of adverse gastrointestinal outcomes, according to an analysis presented at the annual Digestive Disease Week.
“In average-risk patients, aspirin alone optimized the economic balance between cardiovascular and GI outcomes,” said Dr. Martin Van Oijen of Radboud University, Nijmegen Medical Centre, the Netherlands.
Aspirin and clopidogrel, the two most commonly used antiplatelet therapies, increase the risk of GI bleeding, peptic ulcers, and dyspepsia. Concurrent use of proton pump inhibitors (PPIs) can reduce the risk of GI events, but at increased cost.
Dr. Van Oijen and his colleagues assessed the cost-effectiveness of various combinations of aspirin, clopidogrel, and PPIs. The base case for this analysis was a 60-year-old man with a 5-year MI risk of more than 3%. Six strategies were considered: aspirin alone, aspirin plus a PPI, clopidogrel alone, clopidogrel plus a PPI, aspirin in combination with clopidogrel, and the combination of aspirin, clopidogrel, and a PPI.
They derived probability estimates from a review of the literature. Costs were evaluated from the perspective of a third-party payer. Medicare reimbursement schemes and wholesale average drug prices were used in the calculations. The primary outcome was the cost increment per quality-adjusted life year (QALY).
Aspirin alone optimized the economic balance between cardiovascular and GI outcomes. In contrast, clopidogrel-based strategies appeared to be cost ineffective.
The researchers hypothesized that the cost of PPIs would have an important effect on outcome. When the cost of a PPI became $2.50 per tablet, the aspirin plus a PPI strategy became viable.