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

Abstract

Objective: To perform a modelled economic analysis of the efficacy and tolerability of aceclofenac in comparison with those of other nonsteroidal antiinflammatory drugs (NSAIDs) used in the treatment of common arthritic disorders including osteoarthritis, rheumatoid arthritis and ankylosing spondylitis.

Design: A decision analytical model was constructed to represent the clinical and economic consequences of NSAID treatment. Probabilities of noncompliance, lack of efficacy and incidence of adverse events were obtained from comparative randomised double-blind clinical trials. Local unit treatment costs were used and an expert panel was convened to estimate resource use. Both classical foldback analysis and bootstrap methods were used to compute point estimates and 95% confidence limits of costs for NSAID treatment.

Patients and interventions: Data were obtained from 12 randomised double-blind clinical trials included in an earlier meta-analysis.

Main outcome measures: Total costs to the healthcare provider, including NSAID treatment costs (drug acquisition costs and physician visits for prescription) and iatrogenic costs (substitution treatment costs for patients not achieving clinical efficacy and costs of medical visits, treatment, diagnostic tests and hospital stays associated with adverse events) and the iatrogenic cost factor (ICF) were used as the primary outcome measures.

Results: Means and 95% confidence intervals revealed no statistically significant differences in total costs between aceclofenac and other NSAIDs, with the exception of piroxicam, despite substantial differences in drug acquisition costs. The ICF for aceclofenac was lower than that for all other comparators, and differences in ICF between aceclofenac 200 mg/day and diclofenac 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.