[Cost-analysis of viscosupplementation treatment with hyaluronic acid in candidate knee replacement patients with osteoarhritis].

A high percentage of knee osteoarthritis finally need a knee replacement. Previous treatments used including viscosupplementation with hyaluronic acid can delay the knee replacement. The objective of this study was to estimate the economic impact in the short, medium and long term of the knee replacement delay, by conducting a budget impact analysis of the incorporation of viscosupplementation to the treatment of knee osteoarthritis. From the data of patients treated at a specialized Knee Osteoarthritis Unit we built a discrete event simulation model that reproduced the progress of patients, as it could represent changes in the health status of an individual and their interaction with the system. The model allowed the number of prostheses and replacements performed each year to be calculated in a population including 1,000 patients each year according to the use of viscosupplementation. The budget impact analysis was estimated for 10 years by adding the cost of each treatment. A total of 224 patient candidates to receive a knee replacement were studied. The viscosupplementation use delayed the need to perform the knee replacement by 2.67 years The budgetary impact would lead to net savings during the 10 years. However, it is much greater in the earlier years. The sum of the savings in the first three years would be 36 million euros. The study concludes that the use of viscosupplementation reduced the economic burden of knee osteoarthritis in the health system as a result of delayed knee replacement. The simulation model enabled the economic impact in both the short and long term to be analysed.