Glucosamine Combined With Chondroitin Sulfate For Knee Osteoarthritis:A Systematic Review

Objective. To evaluate the efficacy and safety of glucosamine(GS) combined with chondroitin sulfate(CS) for knee osteoarthritis(OA).Methods.We included randomized controlled trials(RCT) of GS combined with CS for knee OA. The participants were those patients with knee OA. The primary outcome were Western Ontario and Mc Master Universities Osteoarthritis Index(WOMAC,0-100). We searched the CENTRAL, PUBMED, EMBASE and CBM(search date Janurary, 2016). Two reviewers independently identified the included trials, evaluated their methodological quality and extracted data. The Cocharane collaboration's Review manager 5.3 software was used for data analysis.Results. The search retrieved 867 titles, of which 4 RCTs were included in this systematic review. The overall risk of bias was low in 3 trials and high in 1. There were 4 RCTs comparing combination group with GS group. The sample size ranged from 72 to 634 with a total number of 1145 patients. There were 3 RCTs comparing combination group with CS group. The sample size ranged from 130 to 635 with a total number of 1067 patients. The outcomes analysis showed:(1) Among those 4 RCTs comparing the combination with GS, three RCTs reported WOMAC score. One is short-term(< 6 months) study(n=72), the other two were long-term(?6 months) study(n=937). Only the short-term study showed that the combination group was significantly better than GS group in the WOMAC score(including pain, stiffness and function, 0-100). Summarized results of these 3 RCTs showed no significant difference between combination group and GS group. MDs of WOMAC score in pain, stiffness and function were-6.60(95% CI-18.79, 5.59),-15.90(-43.09, 11.29) and-6.44(-16.46, 3.59).(2) Two long-term(?6 months) study(n=937) compared the combination with CS group and showed no significant difference. Pooled MD of WOMAC score in pain and function were-0.80(-4.96, 3.36) and-1.76(-4.46, 0.94)respectively.(3) Subgroup analysis in 1 RCT showed that in moderate-to-severe knee pain group(n=142) combination obviously improve the WOMAC score in pain, stiffness and function compared with GS group, but the differences were not statistically significant. MD were-7.08(-14.54, 0.38),-4.40(-13.05, 4.25) and-5.00(-12.41, 2.41). However, the differences of WOMAC score(pain, stiffness and function) between the combination and CS group(n=142) were statistically significant. MD were-10.46(-17.98,-2.94),-9.70(-18.48,-0.92) and 9.39(-17.33,-1.45). In the mild knee pain group, the combination was not significantly better than either GS(n=492) or CS(n=493).Conclusions. There is no evidence to support that the combination of GS and CS for knee OA can significantly improve the WOMAC score compared with either GS or CS. For patients with moderate-to-severe knee pain, combination might be superior to either GS or CS. More studies of high quality are needed to verify the combination of GS and CS for knee OA.