Diacerein superior to glucosamine plus chondroitin for mild knee osteoarthritis
Diacerein appears to be more effective than glucosamine plus chondroitin (GC) for patients with mild-to-moderate knee osteoarthritis (OA), according to a study presented at the 2018 Annual European Congress of Rheumatology (EULAR 2018).
“In the first placebo-controlled trial assessing the effect of diacerein versus GC, improvements occurred for all three criteria: general health, clinical and biochemical,” said researchers.
The trial included 322 Pakistani adults with mild-to-medium knee OA (Kellgren-Lawrence grading 2 or 3; aged 40–65 years), of whom 226 and 191 had complete data by the end of year 1 and 2, respectively. [EULAR 2018, abstract SAT0568]
Significantly more patients in the diacerein than in the GC or placebo groups showed improvements from baseline to year 1 in limitations due to physical health (89.6 percent vs 75.3 percent vs 75 percent; p=0.04). The same was true for improvements by year 2 (91.8 percent vs 75 percent vs 80.3 percent; p=0.04).
Social functioning was likewise significantly improved in the diacerein vs GC patients by the end of year 2 (67.2 percent vs 45.3 percent). Notably, participants who were given placebo also showed greater 2-year improvements relative to GC patients (60.6 percent vs 45.3 percent; p=0.04 for all).
In addition, slightly more patients who received diacerein reported lower pain scores by the end of year 1 than their counterparts who received GC (58.4 percent vs 71.2 percent; p=0.08). No such differences were observed by the end of year 2 or when comparing against patients who received placebo.
In contrast, diacerein conferred relatively smaller fatigue benefits. By the end of year 1, significantly more patients who received GC or placebo showed reduced fatigue than those who received diacerein (80.8 percent vs 86.8 percent vs 66.2 percent; p=0.007).
“A larger proportion of diacerein participants improved their physical role limitation and social functioning in comparison to the other group,” said researchers, adding that this may explain the relatively smaller drop in fatigue measures.
“[I]mprovement in pain, stiffness and physical functioning occurred in all the groups, indicating that perhaps the role of nonpharmacological interventions such as diet, exercise and pain management needs to be further explored,” they added.
For the present randomized, double-blind, placebo-controlled trial, researchers randomized participants to receive twice-daily doses of diacerein (50 mg), GC (1,200 mg) or placebo over 2 years. Only those with knee pain histories of >6 months were eligible for inclusion. All participants received exercise, pain management and diet counselling.
Participant general health (subscales: pain, social functioning, fatigue and role limitation due to physical health) was assessed using the Short Form Health Survey. The Western Ontario and McMaster Universities Arthritis Index (subscales: pain, stiffness and physical functioning) was used to evaluate clinical knee condition.