Iatrogenic cost factors incorporating mild and moderate adverse events in the economic comparison of aceclofenac and other NSAIDs

Objective: To perform a modelled economic analysis of the efficacy and tole rability of aceclofenac in comparison with those of other nonsteroidal anti inflammatory drugs (NSAIDs) used in the treatment of common arthritic disor ders including osteoarthritis, rheumatoid arthritis and ankylosing spondyli tis. Design: A decision analytical model was constructed to represent the clinic al and economic consequences of NSAID treatment. Probabilities of noncompli ance, lack of efficacy and incidence of adverse events were obtained from c omparative randomised double-blind clinical trials. Local unit treatment co sts were used and an expert panel was convened to estimate resource use. Bo th classical foldback analysis and bootstrap methods were used to compute p oint estimates and 95% confidence limits of costs for NSAID treatment. Patients and interventions: Data were obtained from 12 randomised double-bl ind clinical trials included in an earlier meta-analysis. Main outcome measures: Total costs to the healthcare provider, including NS AID treatment costs (drug acquisition costs and physician visits for prescr iption) and iatrogenic costs (substitution treatment costs for patients not achieving clinical efficacy and costs of medical visits, treatment, diagno stic tests and hospital stays associated with adverse events) and the iatro genic cost factor (ICF) were used as the primary outcome measures. Results: Means and 95% confidence intervals revealed no statistically signi ficant differences in total costs between aceclofenac and other NSAIDs, wit h the exception of piroxicam, despite substantial differences in drug acqui sition costs. The ICF for aceclofenac was lower than that for all other com parators, and differences in ICF between aceclofenac 200 mg/day and diclofe nac 150 mg/day, indomethacin 100 mg/day, naproxen 1000 mg/day, tenoxicam 20 mg/day or ketoprofen 150 mg/day were statistically significant. Conclusion: These results show that the comparative overall costs of NSAIDs bears little relation to drug acquisition cost, and that the ICF is one of the most important determinants of overall costs.