Objective: To reexamine the cost-effectiveness of misoprostol, using data from a recently published placebo-controlled trial of misoprostol in > 8,000 patients with rheumatoid arthritis (RA) taking nonsteroidal antiinflammatory drugs (the Misoprostol Ulcer Complications Outcome Safety Assessment [MUCOSA] study).
Methods: Actual clinical events and the rates of endoscopies and upper gastrointestinal (GI) radiographic series, hospitalizations, and surgery for these events were derived from the MUCOSA study and used in a decision analysis. Estimates of costs for the management of these events were derived from the Ontario Case Cost Project database and published economic evaluations; costs were adjusted to 1994 Canadian dollars. Incremental cost-effectiveness (from the viewpoint of the provincial health care plan in Canada) was calculated for the original trial population (risk of a serious GI complication 1%) and for the subsets of patients with medium (3%) and high (6%) risk.
Results: For the original study population, averting 1 serious GI complication by prescribing misoprostol would cost an additional $94,766 (Canadian; range $60,286-137,146). For patients with previous peptic ulcer disease (medium risk), the cost would be $14,943 (range $10,912-32,157), and for patients with previous peptic ulcer disease and age > 75 (high risk), the cost would be $4,101 (range $-220 to $18,146).
Conclusion: Prescribing misoprostol for all patients with RA who are > or =52 years old costs $94,766 for each additional GI event averted. However, when patients at higher risk are specifically selected, the cost per averted GI complication is markedly reduced. These results, based on actual serious event rates and actual data on endoscopies and upper GI series, hospitalizations, and surgeries, provide a better estimate of the true cost-effectiveness of misoprostol than previous analyses based on endoscopic data and modeling of all resource utilizations.