Curcuminoid Treatment for Knee Osteoarthritis: A Randomized Double‐Blind Placebo‐Controlled Trial

Abstract

Treatment of osteoarthritis (OA) is challenging owing to the inefficacy and long-term adverse events of currently available medications including non-steroidal anti-inflammatory drugs. Curcuminoids are polyphenolic phytochemicals with established anti-inflammatory properties and protective effects on chondrocytes. The aim of this study is to investigate the clinical efficacy of curcuminoids in patients suffering from knee OA. A pilot randomized double-blind placebo-control parallel-group clinical trial was conducted among patients with mild-to-moderate knee OA. Patients were assigned to curcuminoids (1500 mg/day in 3 divided doses; n = 19) or matched placebo (n = 21) for 6 weeks. Efficacy measures were changes in Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), visual analogue scale (VAS) and Lequesne's pain functional index (LPFI) scores during the study. There was no significant difference in age, gender, body mass index, and VAS, WOMAC and LPFI scores between the study groups at baseline (p > 0.05). Treatment with curcuminoids was associated with significantly greater reductions in WOMAC (p = 0.001), VAS (p < 0.001) and LPFI (p = 0.013) scores compared with placebo. With respect to WOMAC subscales, there were significant improvements in the pain and physical function scores (p < 0.001) but not stiffness score (p > 0.05). There was no considerable adverse effect in both groups. To conclude, curcuminoids represent an effective and safe alternative treatment for OA.

Effectiveness of curcuminoids in the treatment of knee osteoarthritis: a systematic review and meta‐analysis of randomized clinical trials

“…37 We also excluded one study because there was no relevant outcome 38 and one (abstract) because it was a duplicate of another excluded study. 39 Finally, we included seven studies [40][41][42][43][44][45][46] with a total of 797 participants. Key details of the included studies are shown in Table 1.…”

“…In four studies the proportion of participants with bilateral knee OA ranged from 37% 44 to 100%. 45 Three studies 42,43,46 did not report the proportion of participants with bilateral knee OA. The mean age of the participants ranged from 57 to 69 years, and the duration of intervention was between 4 and 16 weeks.…”

“…The duration of symptoms was approximately 20 months in one study 40 and 12 months in another 41 ; a third study 42 included participants with at least 6 months duration of symptoms. Four studies [43][44][45][46] did not report the duration of OA symptoms for their study participants. There were no significant differences in baseline characteristics of participants between the intervention and control groups (Table S1).…”

“…Three studies 40,41,46 used similar methods to extract curcuminoids; however, the concentration of pure curcumin was between 75% and 85% in two studies, 40,41 while the concentration was reported as ≥ 95% in the third. 46 One study 42 used polysaccharide to enhance the bioavailability of curcuminoids, another 45 combined curcuminoids with Bioperineâ to enhance bioavailability, while another 44 used surface-controlled water-dispersible curcumin to increase the bioavailability. The method used to extract curcuminoids in one study 43 was unclear.…”

“…Five studies [42][43][44][45][46] used a placebo as comparator, while ibuprofen was used as the comparator in two studies. 40,41 Rescue medications used were tramadol, 41 acetaminophen, 42 celecoxib or pain relief patches 44 and naproxen.…”