Background Globally, the incidence of knee osteoarthritis (KOA) is increasing. The treatments available for many years have included both pharmacological and non-pharmacological modalities.

Objectives To examine whether Diacerein is more effective than glucosamine-chondroitin or a placebo in slowing disease progression, physical functioning and/or pain in patients with mild-moderate knee osteoarthritis

Methods In a double-blind RCT, 322 Pakistani patients between 40–65 years with mild to medium KOA (Kellgren-Lawrence Grading 2 or 3) and a history of knee pain >6 months were randomised to receive Diacerein (50 mg twice daily) or Glucosamine-chondroitin (1200 mg twice daily) or a placebo (twice daily) for 2 years. All groups received exercise, diet and pain management counselling. Participant’s general health and knee condition was assessed at baseline, 6-, 12-, 18- and 24 months using Short Form³⁵ Health Survey (SF 36) and WOMAC Index respectively. The Cartilage Oligomeric Matrix Protein (COMP) test was carried out at baseline, 12- and 24 months to assess progression of Knee OA. Improvement was considered at least a 10 point increase in SF36 score from baseline; a 10 point decrease in WOMAC and a 1 unit decrease in COMP.

Results Participants with complete data at the end of year 1 (n=226) and year 2 (n=191) were analysed. At baseline, no significant differences were found in the distribution of gender, age, BMI, COMP levels, SF36, WOMAC scores as well as KL grade levels. Compared to baseline, at year 1 and 2 follow-up, participants in the Diacerein group had statistically significant improvement in their ability to work and other physical activities in comparison with those in the other 2 groups. By the end of year 2, social functioning improved in the Diacerein group as compared to those in the Glucosamine-Chondroitin (GC) group. Compared to placebo group, social functioning improved in the Diacerein group. A greater proportion of GC and placebo group participants reported reduction in their fatigue levels than those in the Diacerein group (p value=0.007). Using the SF36 scale, in comparison to baseline, improvements were made in all the groups albeit with no between group differences for physical functioning, emotional well-being, and general health. Using the WOMAC index, improvement occurred in all its domains of pain, stiffness and physical functioning, but statistically larger proportion of stiffness reduction took place in the GC group.

Conclusions In the first placebo-controlled trial assessing the effect of Diacerein versus GC, improvements occurred for all 3 criteria: general health, clinical and biochemical. A larger proportion of Diacerein participants improved their physical role limitation and social functioning in comparison to the other groups. Fatigue reduction was not the highest in the Diacerein group but that could be attributed to their increased physical and social functioning. Using the WOMAC scale, improvement in pain, stiffness and physical functioning occurred in all the groups indicating that perhaps the role of non-pharmacological interventions such as diet, exercise and pain management needs to be further explored. Biochemical COMP levels decreased in half the participants in comparison to baseline in all groups.

Disclosure of Interest None declared