The cost-effectiveness of aspirin versus cyclooxygenase-2-selective inhibitors for colorectal carcinoma chemoprevention in healthy individuals.

BACKGROUND

Aspirin therapy is accepted widely for secondary prevention in patients with documented cardiovascular disease, but there is a growing trend among healthy individuals to use aspirin as primary chemoprevention for both cardiovascular and oncologic diseases. Accruing evidence suggests that cyclooxygenase-2-selective inhibitors (coxibs) may be effective for colorectal carcinoma (CRC) chemoprevention but would not provide the primary cardiac benefit of aspirin.

METHODS

A computer-based Markov model simulated hypothetical cohorts of healthy men age 50 years who took either 325 mg of enteric-coated aspirin daily or celecoxib at a dose of 400 mg twice a day. Patients in both cohorts could develop drug-related complications that would lead to its discontinuation. The aspirin group also was modeled to have a decreased rate of coronary ischemic events; however, decreased CRC mortality was not modeled in either group based on the assumption that the two treatments were effective equally in this regard. Data sources included published literature and the Centers for Medicare and Medicaid Services. Endpoints used to compare the two strategies included quality-adjusted life years (QALYs), mortality and complication rates, and cost. The analysis was from a societal perspective with a time horizon of 10 years from age 50 years. Extensive sensitivity analyses were performed.

RESULTS

Aspirin therapy resulted in 0.03 more QALYs and cost $23,000 less than coxib therapy over a 10-year period. Compared with the aspirin group, the coxib group had 3.877% more complications and 0.17% more deaths. Alternatively stated, coxib therapy resulted in 1 patient complication or death for every 26 or 588 patients treated with coxibs, respectively.

CONCLUSIONS

Assuming equal efficacy in CRC prevention over a 10-year period, aspirin was both more effective and less costly than coxib therapy when used for primary chemoprevention of CRC.