P02.119
Purpose: To examine the effectiveness of a recently developed special extract from willow bark with an enhanced content of polyphenols under pragmatic conditions.
Methods: Open observational trial with patients suffering from chronic musculosceletal pain of different etiology (fibromyalgia, chronic back pain, osteoarthritis) in a multi-centre outpatient setting (university outpatient centre, pain centres, practices with family medicine). Duration 24 weeks, primary endpoint overall pain (VAS) measured at 6 visits, secondary endpoint pain as registered in diaries, and physicians' judgement on tolerability Pre-existing pain medication could be continued (esp. NSAID and opioids).
Results: 436 patients (ITT) from 74 study centres were included. Mean age was 59.3+12.1y, 108 (24.5%) male, leading etiologies (multiplicity possible): low back pain 61 (59.4%), osteoarthritis 245 (56.2%), fibromyalgia 67 (15.4%), others 77 (17.7%), 258 (59.2%) with more than 5y duration. 277 (63.5 %) patients (PP) completed the study after 24 weeks, 159 (36.5 %) terminated the study prematurely mainly due to lack of efficacy. Mean VAS (0–100) dropped continuously from baseline 58.4±22.6 to 31.8±22.5 after 24 weeks, reaching significance (p<0.05, WILCOXON test for related samples) at visit 2 after 3 weeks and any time thereafter. There was no significant difference between ITT and PP populations in VAS outcome. Decrease of pain by diaries followed a similar pattern to VAS at the 6 visits. Adverse events were reported more often at 3 weeks (4.8%) than at 24 weeks (0.3%). By using the conservative LOCF method, as well as a linear model fitted in the transformed domain to regress the wavelet coefficients to a set of interesting predictors, significant influences of the variables age, BMI, and concomitant treatment could be identified as predictors.
Conclusion: Phytotherapy with STW 33-I might be effective in long-term pain therapy of musculoskeletal etiolgies. It seems appealing, to do further studies of this type with consumption of NSAID and opioids as primary parameters.
Contact: Rainer Stange, r.stange@immanuel.de
