Review Article

Quality of Evidence Supporting the Role of Curcuma Longa Extract/Curcumin for the Treatment of Osteoarthritis: An Overview of Systematic Reviews

Table 2

Summary of evidence.

Author, year (country)OutcomesStudies (participants)Relative effect (95% CI)Heterogeneity

(a) (CLE/C vs placebo)
Raveendhara R. 2018 (USA) [26]Pain5 (331)SMD: −0.81 (−1.25, −0.37)I2 = 71%
Function3 (232)SMD: −0.48 (−0.74, −0.22)I2 = 0%
The use of rescue drugs3 (141)RR: 0.65(0.48, 1.05)I2 = 74%
Incidence of withdrawal from treatment due to adverse events4 (288)RR: 0.90 (0.21, 3.79)I2 = 14%
Adverse events3 (247)RR: 2.22 (0.94, 5.26)I2 = 0%
James W. Daily 2016 (South Korea) [34]VAS3 (104)MD: −2.04 (−2.85, −1.24)I2 = 27%
WOMAC scale3 (122)MD: −15.36 (−26.9, −3.77)I2 = 91%
An-Fang Hsiao 2021 (China) [28]VAS7 (501)SMD: −2.073 (−4.339, 0.194)I2 = 96.6%
Adverse events6 (527)Or: 1.115 (0.548, 2.271)I2 = 0%
Igho J. ONAKPOYA 2017 (UK) [32]VAS5 (366)SMD: −3.30(−4.99,−2.01)I2 = 97%
WOMAC scale3 (167)SMD: −4.42 (−6.66, −2.19)I2 = 93%
LPFI2 (107)MD: −2.69 (−3.48,−1.90)I2 = 0%
Zhiqiang Wang 2021 (Australia) [33]Pain12 (1,071)SMD = −0.82 (−1.17, −0.47)I2 = 86.23%
Function10 (973)SMD = −0.75 (−1.18, −0.33)I2 = 90.05%
Adverse events8 (791)RD: 0.00 (−0.06,0.06)I2 = 31.85%
The use of rescue drugs7 (300)RD: −0.13 (−0.24,−0.01)I2 = 54.36%
Analgesic discontinuation rate4 (154)RD: 0.36 (0.1, 0.61)I2 = 87.06%
Wenli Dai 2021 (China) [29]VAS8 (569)MD: −2.21 (−3.15, −1.28)I2 = 94%
WOMAC scale5 (377)MD: −11.93 (−16.63, −7.23)I2 = 81%
WOMAC (pain) scale5 (377)MD: −1.94 (−2.80, −1.09)I2 = 76%
WOMAC (physical) scale5 (377)MD: −6.45 (−9.10,−3.80)I2 = 83%
WOMAC (stiffness) scale5 (377)MD: −0.53 (−0.95, −0.11)I2 = 77%
Adverse events7 (623)RR: 1.08 (0.69, 1.70)I2 = 19%
Jian Wu 2019 (China) [30]WOMAC scale3 (146)SMD: −1.30 (−1.66, −0.94)I2 = 37%
VAS2 (98)SMD: −1.65 (−2.11, −1.19)I2 = 0%
Adverse events2 (113)RR:1.46 (0.57, 3.77)I2 = 0%
Liuting Zeng 2021 (China) [31]VAS6 (381)MD: −11.55 (−14.3, −9.06)I2 = 69%
WOMAC (pain) scale4 (315)SMD: −0.66 (−0.88, −0.43)I2 = 34%
WOMAC (physical) scale4 (315)SMD: −0.79 (−1.27, −0.31)I2 = 75%
WOMAC (stiffness) scale4 (315)SMD: −0.35 (−0.57, −0.12)I2 = 26%
Adverse events6 (629)RR: 1.18 (0.71, 1.94)I2 = 25%
Weiyan Gong 2017 (China) [27]VAS2 (82)SMD: −0.69 (−0.99, −0.40)I2 = 48.4%
WOMAC scale2 (82)SMD: −1.44 (−1.91, −0.96)I2 = 0%
Adverse events2 (152)Or: 1.5 (0.65, 3.44)I2 = 0%
Walking distance1 (48)MD: 202.0 (187.56, 216.44)NA

(b) (CLE/C vs CT)
Raveendhara R. 2018 (USA) [26]Pain (vs NSAIDs)2 (422)SMD: −0.05 (−0.41, 0.31)I2 = 60%
Function (vs NSAIDs)1 (331)SMD: −0.02 (−0.24, 0.19)NA
The use of rescue drugs (vs NSAIDs)2 (422)RR 2.46 (0.48, 12.52)I2 = 60%
Incidence of withdrawal from treatment due to adverse events (vs NSAIDs)2 (474)RR: 0.22 (0.05, 0.99)I2 = 0%
Adverse events (vs NSAIDs)2 (467)RR: 0.74 (0.60, 0.91)I2 = 0%
James W. Daily 2016 (South Korea) [34]WOMAC scale (vs painkillers)5 (625)MD: −1.89 (−4.13,0.35)I2 = 94%
An-Fang Hsiao 2021 (China) [28]VAS (vs NSAIDs)2 (256)SMD: −0.329 (−0.540, −0.117)I2 = 0%
Adverse events (vs NSAIDs)3 (623)Or: 0.524 (0.121, 2.279)I2 = 63.2%
Igho J. ONAKPOYA 2017 (UK) [32]WOMAC scale (vs NSAIDs)1 (331)MD: −0.03 (−0.03, 0.09)NA
Zhiqiang Wang 2021 (Australia) [33]Pain (vs NSAIDs)5 (648)SMD = −0.09 (−0.30, 0.12)I2 = 34.97%
Function (vs NSAIDs)3 (477)SMD = −0.14 (−0.36, 0.09)I2 = 20.02%
Adverse events (vs NSAIDs)3 (571)RD: −0.12 (−0.24, −0.01)I2 = 42.74%
The use of rescue drugs (vs NSAIDs)2 (443)RD: 0.02 (−0.01, 0.04)I2 = 0.01%
Jian Wu 2019 (China) [30]WOMAC scale (vs NSAIDs)1 (331)SMD: −0.06 (−0.28, 0.15)NA
Adverse events (vs NSAIDs)2 (159)RR:0.81 (0.63, 1.05)I2 = 0%
Liuting Zeng 2021 (China) [31]VAS (vs NSAIDs)2 (230)MD: −0.34 (−1.25, 0.57)I2 = 0%
WOMAC (pain) scale (vs NSAIDs)1 (331)SMD: 0.04 (−0.18, 0.25)NA
WOMAC (physical) scale (vs NSAIDs)1 (331)SMD: 0.07 (−0.14, 0.29)NA
WOMAC (stiffness) scale (vs NSAIDs)1 (331)SMD: 0.07 (−0.17, 0.27)NA
Adverse events (vs NSAIDs)3 (561)RR: 0.55 (0.34, 0.88)I2 = 70%
Weiyan Gong 2017 (China) [27]VAS (vs NSAIDs)1 (112)MD: 13.00 (8.162,17.838)NA
WOMAC scale (vs NSAIDs)1 (331)MD: 0.13 (−0.302, 0.562)NA
Walking distance (vs NSAIDs)2 (360)MD: −1.17 (−19.7, 17.37)I2 = 0%
Adverse events (vs NSAIDs)3 (491)Or: 0.55 (0.38, 0.81)I2 = 75.3%

Note.The 95% confidence interval does not cross the invalid line.