Cost-Utility Analysis of High Molecular Weight Hyaluronic Acid for Knee Osteoarthritis in Everyday Clinical Care in Patients at a Working Age: An Economic Evaluation of a Randomized Clinical Trial.

OBJECTIVE: Knee osteoarthritis (OA) is associated with high medical costs and especially with high productivity costs, in particular in patients in their working years. High molecular weight (HMW) hyaluronic acid (HA) is an alternative treatment for nonsteroidal antiinflammatory drugs, which are known for their serious side-effects. The cost-utility of intraarticular HMW-HA treatment in these patients is unknown, however, and was assessed in this study. METHODS: Secondary care patients ages 18-65 years with knee OA were randomized to usual care plus HMW-HA (intervention group) or to usual care only (control group). A cost-utility analysis over 52 weeks from the societal and health care perspective was performed. Uncertainty for costs, effects, and cost-utility ratio was analyzed by nonparametric bootstrapping. Baseline imbalance adjustment was done by inverse probability of treatment weighting. RESULTS: In total, 156 subjects were included (intervention group n = 77, control group n = 79). The total of productivity and medical costs was €475 higher in the intervention group at €7,754 (95% confidence interval [95% CI] 5,426, 10,436) versus €7,270 (95% CI 5,453, 9,262). The amount of quality-adjusted life years (QALYs) gained during followup was also higher in the intervention group (0.779 versus 0.727). This variation resulted in an incremental cost-effectiveness ratio of €9,100/QALY from a societal perspective and €8,700/QALY from a health care perspective. When the maximum willingness to pay for conditions similar to knee OA is considered, the probability on cost-effectiveness is 64% and 86%, respectively. CONCLUSION: Intraarticular HMW-HA added to usual care for knee OA is probably cost-effective in the treatment of knee OA.