A double-blind randomized placebo controlled study assessing safety, tolerability and efficacy of palmitoylethanolamide for symptoms of knee osteoarthritis

摘要

BackgroundThe aim of the study was to assess the safety, tolerabilityand efficacy of palmitoylethanolamide (PEA) when dosed at 300mg and 600mg per day on symptoms of knee osteoarthritis.MethodsThis was a single site,comparative, double-blind placebo controlled study in adults with mild to moderate knee osteoarthritis with 111 participants randomized to receive 300mg PEA, 600mg PEA or placebo each day, in divided doses b.i.d, for 8weeks. The primary outcome was the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). The secondary outcomes were the Numerical Rating Scales (NRS)for pain, theDepression Anxiety Stress Scale (DASS), the Perceived Stress Scale (PSS), the Pittsburg Sleep Quality Index (PSQI), the Short Form Health Survey (SF-36), the use of rescue pain medication and clinical safety assessment.ResultsThere was a significant reduction in the total WOMAC score in the 300mg PEA (p=0.0372) and the 600mg PEA (p=0.0012) groups, the WOMAC pain score (300mg PEA, p=0.0074; 600mg PEA, p=<0.001), theWOMAC stiffness score (PEA 300mg, p<0.0490; 600mg PEA, p=0.001) and in theWOMAC function score in the 600mg PEA group (p=0.033) compared to placebo. The NRS pain evaluations for "worst pain" and "least pain" were significantly reduced in the 300mg PEA group (p<0.001, p=0.005) and the 600mg PEA group (p<0.001, p<0.001) compared to placebo. There was a significant reduction in anxiety (DASS) in both active treatment groups (300mg PEA, p=0.042; 600mg PEA group (p=0.043) compared to placebo. There were no changes in the clinical markers and the product was well tolerated.ConclusionsThe study demonstrated that palmitoylethanolamide may be a novel treatment for attenuating pain and reducing otherassociated symptoms ofknee osteoarthritis. Further studies on the pharmacological basis of this anti-inflammatory effect are now required.