title: Efficacy and safety of ginger in osteoarthritis patients: a meta-analysis of randomized placebo-controlled trials.
abstract: The aim of this study was to assess the clinical efficacy and safety of oral ginger for symptomatic treatment of osteoarthritis (OA) by carrying out a systematic literature search followed by meta-analyses on selected studies. Inclusion criteria were randomized controlled trials (RCTs) comparing oral ginger treatment with placebo in OA patients aged >18 years. Outcomes were reduction in pain and reduction in disability. Harm was assessed as withdrawals due to adverse events. The efficacy effect size was estimated using Hedges' standardized mean difference (SMD), and safety by risk ratio (RR). Standard random-effects meta-analysis was used, and inconsistency was evaluated by the I-squared index (I(2)). Out of 122 retrieved references, 117 were discarded, leaving five trials (593 patients) for meta-analyses. The majority reported relevant randomization procedures and blinding, but an inadequate intention-to-treat (ITT) analysis. Following ginger intake, a statistically significant pain reduction SMD = -0.30 ([95% CI: [(-0.50, -0.09)], P = 0.005]) with a low degree of inconsistency among trials (I(2) = 27%), and a statistically significant reduction in disability SMD = -0.22 ([95% CI: ([-0.39, -0.04)]; P = 0.01; I(2) = 0%]) were seen, both in favor of ginger. Patients given ginger were more than twice as likely to discontinue treatment compared to placebo ([RR = 2.33; 95% CI: (1.04, 5.22)]; P = 0.04; I(2) = 0%]). Ginger was modestly efficacious and reasonably safe for treatment of OA. We judged the evidence to be of moderate quality, based on the small number of participants and inadequate ITT populations. Prospero: CRD42011001777.
authors.affiliation: The Parker Institute, Department of Rheumatology, Copenhagen University Hospital, Bispebjerg and Frederiksberg, Denmark. Electronic address: Else.Marie.Bartels@regionh.dk.
authors.forename: E M
authors.initials: EM
authors.lastname: Bartels
authors.affiliation: The Parker Institute, Department of Rheumatology, Copenhagen University Hospital, Bispebjerg and Frederiksberg, Denmark.
authors.forename: V N
authors.initials: VN
authors.lastname: Folmer
authors.affiliation: The Parker Institute, Department of Rheumatology, Copenhagen University Hospital, Bispebjerg and Frederiksberg, Denmark.
authors.forename: H
authors.initials: H
authors.lastname: Bliddal
authors.affiliation: David Geffen School of Medicine, University of California, Los Angeles, CA 90024, USA.
authors.forename: R D
authors.initials: RD
authors.lastname: Altman
authors.affiliation: Institute of Sports Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark.
authors.forename: C
authors.initials: C
authors.lastname: Juhl
authors.affiliation: The Parker Institute, Department of Rheumatology, Copenhagen University Hospital, Bispebjerg and Frederiksberg, Denmark.
authors.forename: S
authors.initials: S
authors.lastname: Tarp
authors.affiliation: Division of Rheumatology, Orthopedics and Dermatology University of Nottingham, Clinical Sciences Building, City Hospital, Nottingham, UK.
authors.forename: W
authors.initials: W
authors.lastname: Zhang
authors.affiliation: The Parker Institute, Department of Rheumatology, Copenhagen University Hospital, Bispebjerg and Frederiksberg, Denmark; Institute of Sports Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark.
authors.forename: R
authors.initials: R
authors.lastname: Christensen
mesh_terms: D020939:Zingiber officinale; D006801:Humans; D010003:Osteoarthritis / Q000188:drug therapy*; D008517:Phytotherapy; D010919:Placebos; D010936:Plant Extracts / Q000009:adverse effects / Q000627:therapeutic use*; D016032:Randomized Controlled Trials as Topic; D016896:Treatment Outcome
chemical_list: D010919:Placebos; D010936:Plant Extracts
keywords: Ginger; Hip; Knee; Meta-analysis; Osteoarthritis; Pain