The level of evidence is downgraded by study quality and imprecise results.
A Cochrane review [Abstract] 1 included 33 studies with a total of 5980 subjects. Due to differing interventions, meta-analyses were restricted to Boswellia serrata (monoherbal) and avocado-soyabean unsaponifiables (ASU) (two herb combination) products.
Five studies of three different extracts from Boswellia serrata were included. 90 days treatment with 100 mg of enriched Boswellia serrata extract improved symptoms compared to placebo (2 studies, 85 patients). Mean pain was 40 points on a 0 to 100 point VAS scale with placebo, enriched Boswellia serrata reduced pain by a mean of 17 points (95% CI 8 to 26); NNTB 2; the 95% CIs did not exclude a clinically significant reduction of 15 points in pain. Physical function was 33 points on the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) 0 to 100 point subscale with placebo, enriched Boswellia serrata improved function by 8 points (95% CI 2 to 14); NNTB 4. Assuming a minimal clinically important difference of 10 points, a clinically important benefit in some people cannot be excluded.
Six studies examined the ASU product Piasclidine® . Moderate-quality evidence from four studies (651 participants) indicated that ASU 300 mg produced a small and clinically questionable improvement in symptoms, and probably no increased adverse events compared to placebo after three to 12 months treatment. Mean pain with placebo was 40.5 points on a VAS 0 to 100 scale (0 is no pain), ASU 300 mg reduced pain by a mean of 8.5 points (95% CI 1 to 16 points); NNTB 8. ASU 300 mg improved function (standardised mean difference (SMD) -0.42, 95% CI -0.73 to -0.11). Function was estimated as 47 mm (0 to 100 mm scale with placebo, ASU 300 mg improved function by a mean of 7 mm (95% CI 2 to 12 mm); NNTB 5 (3 to 19). No serious side effects related to any plant product were reported.
Date of latest search: 2013-08-13
Primary/Secondary Keywords