The efficacy of preoperative administration of gabapentin/pregabalin in improving pain after total hip arthroplasty: a meta-analysis

BACKGROUND: The purpose of this systematic review and meta-analysis of randomised controlled trials (RCTs) was to evaluate the pain control by gabapentin or pregabalin administration versus placebo after total hip arthroplasty (THA). METHODS: In January 2016, a systematic computer-based search was conducted in the Medline, Embase, PubMed, CENTRAL (Cochrane Controlled Trials Register), Web of Science and Google databases. This systematic review and meta-analysis were performed according to the PRISMA statement criteria. The primary endpoint was the cumulative morphine consumption and visual analogue scale (VAS) scores at 24 and 48 h with rest or mobilisation. The complications of vomiting, nausea, dizziness and pruritus were also compiled to assess the safety of gabapentin and pregabalin. Stata 12.0 software was used for the meta-analysis. After testing for publication bias and heterogeneity across studies, the data were aggregated for random-effects modelling when necessary. RESULTS: Seven studies involving 769 patients met the inclusion criteria. The meta-analysis revealed that treatment with gabapentin or pregabalin can decrease the cumulative morphine consumption at 24 h (mean difference (MD) = −7.82; 95 % CI −0.95 to −0.52; P < 0.001) and 48 h (MD = −6.90; 95 % CI −0.95 to −0.57; P = 0.118). Gabapentin or pregabalin produced no better outcome than placebo in terms of VAS score with rest at 24 h (SMD = 0.15; 95 % CI −0.17 to −0.48; P = 0.360) and with rest at 48 h (SMD = 0.22; 95 % CI −0.25 to 0.69; P = 0.363). There was no statistically significant difference between the groups with respect to the VAS score at 24 h postoperatively (SMD = 0.46; 95 % CI −0.19 to 1.11; P = 0.164) and at 48 h postoperatively (SMD = 1.15; 95 % CI −0.58 to 2.89; P = 0.193). Gabapentin decreased the occurrence of nausea (relative risk (RR), 0.49; 95 % CI 0.27–0.92, P = 0.025), but there was no significant difference in the incidence of vomiting, dizziness and pruritus. CONCLUSIONS: On the basis of the current meta-analysis, gabapentin or pregabalin can decrease the cumulative morphine consumption and decrease the occurrence of nausea; however, further trials are needed to assess the efficacy of pain control by gabapentin or pregabalin. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12891-016-1231-4) contains supplementary material, which is available to authorized users.