Background: Selective cyclo-oxygenase-2 inhibitors have been reported to cause fewer gastrointestinal complications when compared with conventional, non-selective, non-steroidal anti-inflammatory drugs (NSAIDs).
Aim: To analyse the cost of celecoxib (selective cyclo-oxygenase-2 inhibitor) and conventional NSAID regimens for the treatment of osteoarthritis and rheumatoid arthritis from the perspective of a public health organization in Hong Kong.
Methods: A decision tree was used to analyse the cost of celecoxib, NSAID alone, NSAID plus histamine2-receptor antagonist, NSAID plus misoprostol and NSAID plus proton pump inhibitor over 6 months. Model outcomes were no gastrointestinal toxicity, gastrointestinal discomfort, symptomatic ulcer, anaemia with occult bleeding and serious gastrointestinal complications. The clinical probabilities were estimated from clinical trials. Resource utilization for gastrointestinal events was determined locally. Sensitivity analysis was performed.
Results: The 6-month costs per base-case analysis were as follows: NSAID plus histamine2-receptor antagonist, 1404 HK dollars (1 US dollar = 7.8 HK dollars); celecoxib, 1545 HK dollars; NSAID alone, 1610 HK dollars; NSAID plus misoprostol, 2213 HK dollars; NSAID plus proton pump inhibitor, 2857 HK dollars. The model was sensitive to the patients' underlying gastrointestinal risk scores, daily cost of NSAID regimen, risk ratio of NSAID plus histamine2-receptor antagonist for symptomatic ulcer, daily cost of celecoxib and daily cost of histamine2-receptor antagonist.
Conclusions: Celecoxib appeared to be the least costly alternative in patients with intermediate to high gastrointestinal risk for the treatment of osteoarthritis and rheumatoid arthritis in Hong Kong.