Krill oil for knee osteoarthritis: A meta-analysis of randomized controlled trials

Knee osteoarthritis, a prevalent musculoskeletal disorder, significantly impacts global health and quality of life. Unfortunately, there is no disease modifying osteoarthritis drugs until now. Krill oil is being explored as a potential alternative, however its efficacy in managing knee symptoms remains unclear. Therefore, the meta-analysis of krill oil in knee osteoarthritis would be interesting and useful.

We conducted a systematic search of PubMed, Cochrane Library, Embase, and Web of Science databases from their inception through November 28, 2024, employing predefined search terms, including "krill oil" and "knee osteoarthritis." We included all relevant randomized controlled trials to ensure a comprehensive analysis. Visual analog scale and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) of pain, stiffness and function were served as primary outcomes. Moreover, blood markers and adverse events were also included.

Five randomized controlled trials involving 730 participants were included. Relative to the usual care group, the krill oil group demonstrated no significant improvement in knee osteoarthritis as measured by visual analog scale; however, it exhibited significant benefits in terms of pain (standardized mean difference [SMD] -0.60; 95% confidence interval [CI] -0.99 to -0.21), stiffness (SMD -0.59; 95%CI -1.04 to -0.14), and functional outcomes (SMD -0.68; 95% CI -1.09 to -0.27) based on WOMAC assessments. Analysis of blood markers also revealed no significant effects of krill oil group compared to the usual care group. Moreover, adverse events in the krill oil group and usual care group also showed no statistical difference. The safety profiles were similar between the 2 groups.

Krill oil presents as a promising safe therapeutic option for knee osteoarthritis; however, its efficacy in pain relief requires further investigation.