The Effects of Curcuma Longa on the Osteoarthritis: A Systematic Review of Placebo-Controlled Clinical Studies

Osteoarthritis (OA) is a joint disorder characterized by chronic, degenerative, and irreversible inflammation leading to pain and disability. The standard drugs are ineffective for many patients and are usually associated with numerous side effects such as gastrointestinal complaints. Curcuma longa and its bioactive compounds have been considered for OA. The objective of this study was to perform a systematic review of the effects of Curcuma longa and its derivatives on OA. Pubmed, Cochrane, and Embase were searched, and PRISMA guidelines were followed to build this review. Only Randomized Clinical Trials (RCTs) that performed placebo-comparison were included. Most included studies showed that Curcuma longa or formulations prepared with curcuminoids can benefit the OA scores such as Visual Analog Scale, Knee injury and Osteoarthritis Outcome Score, Western Ontario and McMaster Universities Osteoarthritis Index; and Lequesne's pain functional index. The use of Curcuma longa extracts or curcuminoids can benefit patients with OA. Nevertheless, the available RCTs show treatment time, doses, and formulations heterogeneity. Thus, the standardization of RCTs can guide researchers and physicians on the dosages and formulations that are most effective in addressing this condition, which is very prevalent in the world's populations.