Effect and Safety of Herbal Medicine Foot Baths in Patients with Diabetic Peripheral Neuropathy:A Multicenter Double-Blind Randomized Controlled Trial

Objective:To evaluate the effect and safety of foot baths with Tangbi Waixi Decoction(TW)in treating patients with diabetic peripheral neuropathy(DPN).Methods:It is a multicenter double-blinded randomized controlled trial.Participants with DPN were recruited between November 18,2016 and May 30,2018 from 8 hospitals in China.All patients received basic treatments for glycemic management.Patients received foot baths with TW herbal granules either 66.9 g(intervention group)or 6.69 g(control group)for 30 min once a day for 2 weeks and followed by a 2-week rest,as a therapeutic course.If the Toronto Clinical Scoring System total score(TCSS-TS)6 points,the patients received a total of 3 therapeutic courses(for 12 weeks)and were followed up for 12 weeks.The primary outcome was change in TCSS-TS score at 12 and 24 weeks.Secondary outcomes included changes in bilateral motor nerve conduction velocity(MNCV)and sensory nerve conduction velocity(SNCV)of the median and common peroneal nerve.Safety was also assessed.Results:Totally 632 patients were enrolled,and 317 and 315 were randomized to the intervention and control groups,respectively.After the 12-week intervention,patients in both groups showed significant declines in TCSSTS scores,and significant increases in MNCV and SNCV of the median and common peroneal nerves compared with pre-treatment(P<0.05).The reduction of TCSS-TS score at 12 weeks and the increase of SNCV of median nerve at 24 weeks in the control group were greater than those in the intervention group(P<0.05).The number of adverse events did not differ significantly between groups(P>0.05),and no serious adverse event was related with treatment.Conclusion:Treatment of TW foot baths was safe and significantly benefitted patients with DPN.A low dose of TW appeared to be more effective than a high dose.(Registry No.Chi CTR-IOR-16009331)