Willow bark extract STW 33-I is safe and effective in the long term-treatment of outpatients with rheumatic pain esp. osteoarthritis or back pain – a subgroup analysis

Objectives:

Degenerative musculoskeletal diseases are of increasing relevance in an ageing population. The efficacy and safety of willow bark extract in the therapy of painful musculoskeletal disorders has been shown in a large number of clinical studies. This 6 months pragmatic surveillance study with STW 33-I (Proaktiv®, extraction solvent water; drug-extract ratio 16 – 23:1) included 436 patients with rheumatic pain mainly due to osteoarthritis and back pain. The patients were treated with STW 33-I monotherapy or in combination with NSAIDs and opioids.

Method:

An extensive case report form including pain questionnaires and patient diary was used for outcome evaluation.

Results:

All patients started treatment with STW 33-I. 61.5% of the patients (N = 268) took no analgetic comedication. 28.9% (N = 126) took a dual therapy with NSAIDs (mostly diclofenac or ibuprofen) and only 3.9% received a triple therapy (STW 33-I + NSAID + opioid). Only 5.7% (N = 25) used other analgesics like gabapentin. The mean change from baseline of the pain intensity score (VAS) was -22.4 (baseline 58,7) in the subgroup of the patients receiving STW 33-I only, -18.0 (baseline 56.0) in the STW 33-I and NSAIDs subgroup and -20.5 (baseline 67.4) in the STW 33-I, NSAIDs and opioids subgroup. These results were comparable to other scales (Likert-Scales, patients' diary) concerning pain intensity at rest and in motion and pain duration.

The tolerability of STW 33-I was distinctly better compared to the other investigated subgroups. No relevant drug interactions were reported.

Conclusions:

These data suggest that the phytomedicinal approach, and especially STW 33-I (Proaktiv®), can be used as a basic treatment in the long term therapy of degenerative joint diseases and that it can be combined with NSAIDs and opioids if necessary.