Efficacy and safety of ginger in osteoarthritis patients: a meta-analysis of randomized placebo-controlled trials

Bartels EM, Folmer VN, Bliddal H, Altman RD, Juhl C, Tarp S, Zhang W, Christensen R · Osteoarthritis and Cartilage

Pain fell in ginger's favour by a standardized mean difference of −0.30 (95% CI −0.50 to −0.09, p = 0.005) with low inconsistency between trials (I² = 27%), and disability by −0.22 (95% CI −0.39 to −0.04, p = 0.01, I² = 0%). Against that, patients given ginger were more than twice as likely to stop treatment because of adverse events (RR 2.33, 95% CI 1.04-5.22, p = 0.04). The authors call ginger modestly efficacious and reasonably safe, and rate the evidence moderate quality.

Population

593 patients across 5 randomized placebo-controlled trials of oral ginger in osteoarthritis, from 122 references screened

Intervention

Oral ginger

Comparator

Placebo

Limitations

Five trials and 593 patients is a small base, and the authors flag inadequate intention-to-treat analyses in the majority of them. An SMD of −0.30 is a small effect. The 593 is itself the number left after a large drop-out. Funded by The Oak Foundation, which the paper records as having no role in the design, the data collection or the reporting, and the authors state that none of them is affiliated with or funded by any manufacturer of ginger. PROSPERO CRD42011001777.