The cost effectiveness of diclofenac plus misoprostol compared with diclofenac monotherapy in patients with rheumatoid arthritis

The objective of our study was to estimate the cost effectiveness of treatment with a fixed-dose combination of diclofenac and misoprostol compared with diclofenac monotherapy in the prevention of nonsteroidal anti-inflammatory drug (NSAID)-induced ulcers in rheumatoid arthritis (RA) patients. A model was used to incorporate estimates of costs, incidence of ulcers and their complications, death rates and the efficacy of misoprostol. The costs per ulcer-free period gained and costs per additional survivor were calculated. Cost effectiveness was calculated for the treatment of all RA patients, and of risk groups only. All costs were measured in 1995 Netherlands guilders (NLG; exchange rate at the time of the study: NLG1 = $US0.60). The analysis showed that if 100 RA patients receive 3 months of treatment with diclofenac plus misoprostol, instead of diclofenac alone, this will lead to overall additional costs of NLG773, while 0.82 symptomatic ulcers and 0.019 deaths will be prevented. If misoprostol is given only to patients at high risk for NSAID-induced ulcer, cost savings will occur instead of additional costs. Univaririte sensitivity analysis showed that the outcomes are sensitive to changes in: (i) the percentage of ulcers treated in the ambulatory setting; (ii) the price difference between diclofenac and the fixed-dose diclofenac-misoprostol combination; (iii) the percentage of ulcers with complications; and (iv) the efficacy of misoprostol. In conclusion, it can be stated that treatment with diclofenac-misoprostol is cost saving in RA patients at high risk for NSAID-induced ulcers. For RA patients in general, the cost-effectiveness of this intervention compares favourably with that of other prophylactic treatments.