Association Between Intra-Articular Hyaluronic Acid Injections and Reduction in Analgesic Prescriptions in Knee...

Background/Objectives: Intra-articular hyaluronic acid (HA) injections are widely used to treat pain and functional limitations in knee osteoarthritis (KOA). However, evidence on their real-world effectiveness in routine clinical practice and their impact on analgesic medication use remains limited. This study assessed changes in analgesic prescribing following HA injections in a large real-world outpatient population. Methods: This retrospective cohort study used data from the IQVIA™ Disease Analyzer database in Germany. Patients with knee osteoarthritis who received a first 20 mg hyaluronic acid injection between 2011 and 2024 and had at least three months of observation before and after treatment were included. Outcomes were (1) the proportion of patients with any analgesic prescription (EPHMRA ATC codes M01A, N02A, N02B) and (2) changes in the number of prescribed analgesic pills within three months before versus after injection. Multivariable logistic regression models evaluated factors associated with post-treatment analgesic prescriptions and reductions in pill counts. Results: A total of 4696 patients were included (mean age 64.5 years; 53.9% women), including 524 treated with Recosyn and 4172 treated with other HA products. The proportion of patients with analgesic prescriptions decreased from 28.6% before injection to 26.2% after injection (p = 0.004). Among Recosyn-treated patients, the proportion declined from 25.0% to 20.0% (p = 0.028). Overall, 70.8% of patients with baseline analgesic use achieved a ≥10% reduction in pill counts and 70.0% achieved a ≥20% reduction. In multivariable analyses, treatment with Recosyn was associated with lower odds of receiving an analgesic prescription after injection (OR 0.67; 95% CI 0.53-0.85) and higher odds of achieving a ≥10% reduction in analgesic pill count (OR 1.64; 95% CI 1.05-2.58). Conclusions: In routine outpatient practice, HA injections were accompanied by modest reductions in analgesic prescribing among patients with KOA. Numerically greater reductions were observed among patients treated with Recosyn compared with other HA products; however, these findings should be interpreted with caution given the observational design, potential residual confounding, and the absence of a non-treated comparator group. These results should be considered hypothesis-generating.