The Cost-Effectiveness of Cyclooxygenase-2 Selective Inhibitors in the Management of Chronic Arthritis

View larger version (19K): [in a new window]   Figure 1. Truncated decision model. The base-case patient has chronic arthritis, is at average risk for ulcer complications, and is not taking concurrent aspirin. The clinician may either treat with naproxen, 500 mg twice daily, or with a coxib, once daily. The extended tree (A) is shared by the coxib arm, with the exception of switching to coxibs if ulcer complications develop. See text for details about individual strategies and for assumptions about downstream costs and effects (not represented in the figure). EGD = esophagogastroduodenoscopy; GI = gastrointestinal; NUD = nonulcer dyspepsia; PPI = proton-pump inhibitor.

View larger version (40K): [in a new window]   Figure 2. Meta-analysis using the fixed-effects model of randomized, controlled trials that report upper gastrointestinal dyspeptic symptoms in patients receiving a coxib versus a nonselective nonsteroidal anti-inflammatory drug. The summary estimate is the relative risk (RR). CLASS = Celecoxib Long-term Arthritis Safety Study; SUCCESS = Successive Celecoxib Efficacy and Safety Study.

View larger version (21K): [in a new window]   Figure 3. Meta-analysis using the fixed-effects model of randomized, controlled trials that report clinically significant ulcer complications (symptomatic ulcer, ulcer hemorrhage, or ulcer perforation) in patients receiving a coxib versus a nonselective nonsteroidal anti-inflammatory drug. The summary estimate is the relative risk (RR).

View larger version (44K): [in a new window]   Figure 4. Probabilistic sensitivity analysis using 1000 trials. This analysis simultaneously varies all parameters over the full range of plausible values. Each point represents the incremental cost-effectiveness ratio generated by one trial through the simulation. The median incremental cost-effectiveness ratio of $268 000 per quality-adjusted life-year (QALY) gained is shown (solid line), and, by definition, 50% of the trials fall on either side. Points below and to the right of each line represent trials that generated an incremental cost-effectiveness ratio below the specified threshold. For example, if a third-party payer was willing to pay $150 000 per QALY gained for coxib therapy, then only 4.3% of the patients in this simulation would fall within the budget. WTP = willingness-to-pay thresholds.