Lipoic Acid Combined with Epalrestat versus Lipoic Acid in Treating Diabetic Peripheral Neuropathy:A Meta-analysis

Objective To compare the clinical effectiveness of lipoic acid combined with epalrestat versus lipoic acid in treating diabetic peripheral neuropathy(DPN). Methods Randomized controlled trials(RCTs) and clinical controlled trials on lipoic acid versus epalrestat for DPN before February 2016 were searched through five databases:CNKI,CBM,VIP,Wanfang,and PubMed. The quality of the included trials were assessed using Cochrane software and Jadad scores. Data were analyzed with Review Manager 5.3 software. Results Nine studies were included in the analysis. Meta analysis showed that the lipoic aid monotherapy was significantly inferior to lipoic acid-epalerestat combination therapy [RR=0.58,95%Cl(0.47,0.71),P<0.00001]. Inferiority of the lipoic acid monotherapy was also shown in nerve conduction velocity with WMDs of-4.94 [95%Cl(-7.41,-2.46),P<0.0001] for median motor nerve conduction velocity(MNCV),-5.08 [95%Cl(-7.68,-2.49),P=0.0001] for peroneal MNCV,-4.24 [95%Cl(-6.20,-2.29),P<0.0001] for median sensory nerve conduction velocity(SNCV),and-3.66 [95%Cl(-5.02,-2.31),P<0.00001] for peroneal SNCV. Sensitivity analysis showed that the results were robust. However,the included trials were limited by simple design,few subjective indicators,and short follow-up time. Conclusions Lipoic acid combined with epalrestat is better than lipoic acid alone in the treatment of DPN,as well as the MNCV and SNCV of median or peroneal nerve. Due to the low quality of the included studies,high-quality RCTs are warranted to validate the results.