Symptomatic Efficacy of Pharmacological Treatments for Knee Osteoarthritis: A Systematic Review and a Network Meta-Analysis with a 6-Month Time Horizon

Introduction Several pharmacological treatments aiming at a better symptomatic control of osteoarthritis (OA) are used in daily practice but their efficacy is often disputed. The purpose of this network meta-analysis (NMA) is to assess the efficacy on pain and function of the drugs that are most widely prescribed against knee OA. Methods Medline, Scopus, and Cochrane database of systematic reviews were searched for randomized controlled trials published up to August 2019 and assessing the efficacy of knee OA treatments using a 6-month time horizon. Pain and function changes from baseline were the primary outcomes. A Bayesian network meta-analysis was run and standardized mean differences (SMDs) with 95% credibility intervals (95% CrIs) were calculated. Results 9697 references were identified and 80 RCTs were concordant with our inclusion criteria (79 studies involving 15,609 individuals reported pain outcomes and 55 studies involving 13,655 individuals reported function outcomes). A significant decrease in pain was observed for the intra-articular (IA) combination of hyaluronic acid (HA) and triamcinolone (SMD - 0.49, 95% CrI - 0.78; - 0.19), vitamin D (SMD - 0.31, 95% CrI - 0.56; - 0.06), IA HA (SMD - 0.29, 95% CrI - 0.40; - 0.17), prescription-grade crystalline glucosamine sulfate (pCGS) (SMD - 0.29, 95% CrI - 0.58; - 0.004), and prescription-grade chondroitin sulfate (pCS) (SMD - 0.26, 95% CrI - 0.44; - 0.08). Significant improvements in physical function were found with pCGS (SMD - 0.44, 95% CrI - 0.66; - 0.21), vitamin D (SMD - 0.30, 95% CrIs - 0.49; - 0.11) and IA HA (SMD - 0.21, 95% CrIs - 0.31; - 0.11). Conclusion Six months of treatment with IA HA, pCGS, pCS, vitamin D and the combination of IA HA and triamcinolone improve pain and/or physical function in patients suffering from knee OA.