Osteoarthritis (OA) is the most common articular disease. Common OA treatments are either not effective or associated with side effects. Calcium-containing crystals are quite common in primary OA and they worsen or may cause OA through induction of inflammation by neutrophils. Colchicine inhibits urate-crystal and calcium-pyrophosphate (CPP) crystal induced inflammation and elastase, a matrix-metalloproteinase (MMP) that play a pivotal role in degenerative joint processes. Hence, it was hypothesized that it may have symptom-modifying effects on OA.
Sixty-one postmenopausal patients with primary knee OA were enrolled. None of them had joint involvement atypical for OA or evidences of chondrocalcinosis in radiographic studies suggesting the presence of calcium-pyrophosphatedeposition-disease (CPPD). Participants were allocated to two groups receiving 0.5mg colchicines BID or placebo. Both groups received common OA treatments. Acetaminophen less than 2gr/day was used as rescue-analgesic. The efficacy end points were: patients' global assessment and physician's global assessment, recorded on a VAS (visual analogue scale). Statistical analysis was performed 3 months later.
Thirty-one patients were assigned to the colchicine group. Fifty-eight patients were present for the last survey. Only 1 patient in colchicine group encountered adverse effect of colchicine without significant difference between the two groups. Acetaminophen consumption was significantly less in the colchicine (879.3±369.7) compared to placebo group (1620.7±393.1, p=0.000). Improvement rate at the end of 3 months was significantly higher in the colchicine group for both patients' global assessment and physician's global assessment measures compared to placebo group, (11.14±4.06 vs. 3.14±2.18, p=0.000) and (9.83±3.799 vs. 3.72±3.35, p=0.000), respectively.
The efficacy and safety of colchicine for pain reduction in OA was affirmed by our double-blind randomised controlled trial.