Analysis of the Health and Budgetary Impact of Chondroitin Sulfate Prescription in the Treatment of Knee Osteoarthritis Compared to NSAIDs and COXIBs

BACKGROUND: Chondroitin sulfate, alone or associated with glucosamine (CS), is an effective treatment of osteoarthritis, better tolerated than non-steroidal anti-inflammatory drugs (NSAIDs) and cyclooxygenase 2 inhibitors (COXIBs) at gastrointestinal, cardiovascular and renal levels. OBJECTIVE: To estimate the health impact (toxicity by NSAIDs/COXIBs avoided with CS with or without glucosamine) and economic impact (savings due to avoided toxicities) of treatment of knee osteoarthritis with CS compared to NSAIDs/COXIBs, as a consequence of the avoidance of mild-moderate or severe gastrointestinal adverse effects (GIAE), ischaemic heart disease (IHD), acute kidney insufficiency (AKI) and chronic kidney failure (CKF). METHODS: We compared the current situation (available reimbursed prescription with CS) with a hypothetical situation without CS (treatment only with NSAIDs/COXIBs). The frequency of GIAE, IHD, AKI and CKF with CS and NSAIDs/COXIBs was obtained from published ad hoc studies. The cost of AE management and of the drugs (180 days of treatment) was obtained from Spanish sources. A probabilistic economic model was made for a 3-year period, both at national (NHS) and regional levels. Sensitivity analyses were performed for different durations of treatment (90 and 240 days). RESULTS: In Spain, it is estimated that 519,130, 513,616 and 507,377 patients with knee osteoarthritis will be treated with NSAIDs/COXIBs and 112,775, 114,963 and 117,262 with CS in 2020, 2021 and 2022, respectively. Due to better CS tolerability, 55,098 mild-moderate GIAE, 3060 severe GIAE, 204 IHD, 1089 AKI and 733 CKF would be avoided in 3 years. Discounting the cost of the drugs, the three-year savings for the NHS would be 21.8 (12.7–29.5) million euros. CONCLUSION: Due to its better tolerability profile, CS treatment is expected to prevent thousands of AEs over the next 3 years, some of which may be life-threatening for patients, while generating considerable savings for the NHS.