Efficacy of curcumin and Boswellia for knee osteoarthritis: Systematic review and meta-analysis

Bannuru RR, Osani MC, Al-Eid F, Wang C · Seminars in Arthritis and Rheumatism

Against placebo, curcuminoids reduced pain (SMD -0.81; 95% CI -1.25 to -0.37; 5 trials, N=331) and boswellia more so (SMD -2.04; -2.81 to -1.27; 4 trials, N=216), with function improving on both. Against ibuprofen, curcuminoids showed no difference in pain (SMD -0.05; -0.41 to 0.31) across the two trials that made the comparison, which the authors grade Very Low quality for risk of bias, heterogeneity and imprecision, and no difference in function in the single trial reporting it. Patients on curcuminoids were less likely to have a gastrointestinal adverse event (RR 0.74; 0.60 to 0.91) and less likely to withdraw for one (RR 0.22; 0.05 to 0.99), and reached for rescue medication more often on an interval spanning 1 (RR 2.46; 0.48 to 12.52). No trial compared boswellia against an approved NSAID. The authors conclude the evidence base is not adequate in size or quality to support any clinical practice recommendation.

Population

11 RCTs of curcuminoid or boswellia formulations in knee osteoarthritis

Intervention

Curcuminoid or boswellia formulations

Comparator

Placebo or NSAIDs

Limitations

Study quality was low overall and most included trials enrolled fewer than 100 people. All four boswellia-versus-placebo trials were manufacturer-funded or carried a manufacturer employee as co-author; so were two of the five curcuminoid trials, a third took its study medication from the manufacturer, and a fourth is an unpublished abstract whose funding could not be established. The review itself is NIH-supported and independent of the supplement industry.