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 searched the CENTRAL (Issue 1, 2016), PUBMED (1946 to 2016. 1. 20), EMBASE (1947 to 2016. 1. 20), CBM (1978 to 2016. 1. 20), CNKI (1994 to 2016. 1. 20), WanFang Data (1980 to 2016. 1. 20) and VIP (1989 to 2016. 1. 20) and we searched randomized controlled trials (RCT) of GS combined with CS for knee OA. Two reviewers independently identified the included trials, evaluated the quality of methodology and extracted data. The Review manager 5.3 software was used for data analysis. Results Four RCTs were included in this systematic review. The combination group compared with GS group, a total number of 1 145 patients, and the combination group compared with CS group, a total number of 1 067 patients. The outcomes showed: ① Among those 4 RCTs that comparing the combination with GS, three RCTs reported western ontario and mcmaster universities osteoarthritis index (WOMAC) score. Summarized results of these 3 RCTs showed no significant difference between combination group and GS group (all P values >0.05). MDs of WOMAC score in pain, stiffnessand 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 (all P values >0.05). Pooled MD of WOMAC score in pain and function were -0.80(-4.96, 3.36) and -1.76(-4.46, 0.94) respec-tively. 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, stiffnessand function compared with CS groupand the differences werestatistically significant (all P values <0.05). MDs were -10.46(-17.98, -2.94), -9.70(-18.48, 0.92) and 9.39(-17.33, -1.45). Conclusion There is no evidence to support that the combination of GS and CS for knee OA cansignificantlyimprovethe WOMAC score compared with either GS or CS. For patients with-moderate-to-severe knee pain, combination might be superior toeither GS or CS. Key words: Osteoarthritis, knee; Glucosamine; Chondroitin sulfate; Systematic review