Turmeric extract eases knee pain in randomized trial
An extract made from Curcuma longa, commonly known as turmeric, outperformed placebo for the treatment of osteoarthritis-related knee pain in older adults but had no significant impact on knee effusion-synovitis or cartilage composition, data showed.
“The current pharmacological options for the treatment of [osteoarthritis] are only moderately effective and are contraindicated in patients with comorbidities and are often associated with adverse events,” Benny Antony, MD, PhD, a senior research fellow at the National Health and Medical Research Council of Australia, told Healio Primary Care.
According to Antony, previous studies have shown that various types of Curcuma longa extract effectively and safely treat osteoarthritis. However, the current study may be the first to ascertain the efficacy of Curcuma longa on osteoarthritis symptoms and effusion–synovitis volume on MRI in older adults, he said.
Researchers recruited 70 patients aged 40 years or older with knee pain of 40 mm or greater on a visual analogue scale (VAS). The patients — 39 of whom were women — were randomly assigned in an approximate 1:1 ratio to receive either two capsules containing 1,000 mg of Curcuma longa or placebo daily for 12 weeks.
Antony and colleagues reported that the Curcuma longa recipients had significantly improved VAS scores, by –9.1 mm (95% CI, –17.8 to –0.4 mm). The Curcuma longa cohort’s Western Ontario and McMaster Universities Osteoarthritis Index knee pain scores also significantly improved (–47.2 mm; 95% CI, –81.2 to –13.2). In addition, four patients in the Curcuma longa group stopped or reduced the number of NSAIDs, acetaminophen and/or paracetamol they were taking prior to the study.
However, the differences in effusion-synovitis volume (3.2 mL; 95% CI, –0.3 to 6.8) and lateral femoral cartilage T2 relaxation time (–0.4 milliseconds; 95% CI, –1.1 to 0.3) between the two groups was not significant.
According to the researchers, 14 patients in the Curcuma longa cohort and 18 in the placebo cohort reported at least one adverse event — most of them gastrointestinal or musculoskeletal — during the study. Severe adverse events were reported in two patients in the placebo group, but researchers did not consider them to be treatment related.
Antony noted that there are more than 300 million cases of knee osteoarthritis worldwide, and it is increasingly being recognized as a “serious disease.” He called for long-term studies to assess the safety and efficacy of turmeric extracts for the treatment of osteoarthritis.
“The maximum duration of the existing studies is only up to 16 weeks,” he said. “We are aiming to conduct a larger multicenter clinical trial with a longer duration of follow-up to demonstrate the potential of Curcuma longa extract as a disease-modifying treatment for knee osteoarthritis.”