Topical formulation of Pistacia vera L. pericarp on knee osteoarthritis: A randomized placebo controlled clinical trial

Abstract

The pericarp of Pistacia vera L. is considered a rich source of natural phenolic compounds. Recent studies have examined the anti-inflammatory and painkiller properties of pistachio pericarp. In this randomized placebo-controlled clinical trial, the impact of a topical formulation of pistachio pericarp (TFPP) was investigated on knee osteoarthritis (OA). This was a randomized, double-blind clinical trial with three groups of 25 patients with OA. The diagnosis was made according to the American College of Rheumatology (ACR) criteria and approved by a rheumatologist. Subjects were randomly divided into three groups: piroxicam, TFPP, and placebo. Over eight weeks, patients were treated twice daily. Finally, knee pain and severe pain, stiffness, and physical function were assessed using the visual analogue scale (VAS) and Western Ontario and McMaster University Osteoarthritis Index (WOMAC) criteria at baseline, one and two months after the intervention, respectively. The patients (n=75) were middle-aged and older adults with a BMI>25 kg/m2. Compared to the placebo, the mean VAS (VAS two-months intervention = -1.7; 95%CI; -2.38,-1.08), total WOMAC (Total WOMAC two-months intervention =-2.2; 95%CI: -2.97,-1.55), pain intensity (Pain two-months intervention =-1.7; 95% CI: -2.42,-1.11), stiffness (Stiffness two-months intervention = -1.8; 95%CI: -2.47,-1.15), and physical performance (Physical performance two-months intervention =-1.8; 95%CI: -2.55,-1.21) significantly improved, indicating the potential efficacy of pistachio pericarp compounds in alleviating OA symptoms. The results of this study demonstrated that TFPP is effective at relieving pain and could be used as a safe supplement to treat OA-related pain. IRCT20210912052445N1