Clinical Evidence of Chinese Herbal Medicine for Treatment of Idiopathic Sudden Sensorineural Hearing Loss from Chinese Literature

摘要

Purpose: To provide a comprehensive summary of all clinicalevidence on Chinese herbal medicine (CHM) for idiopathicsudden sensorineural hearing loss (ISSHL) published in Chineseliterature.Methods: We systematically searched randomized clinicaltrials (RCTs), clinical controlled trials (CCTs), case series(CSs) and case reports (CRs) which reported CHM for ISSHLthrough four main Chinese electronic databases from theirinception to March 2014. We bibliometrically analyzed thestudies and assessed the methodological quality of RCTs usingthe Cochrane risk of bias tool.Results: A total of 299 clinical studies with involving 22,237participants were identified including 150 RCTs, 42 CCTs,80 CSs and 27 CRs. The number of publications increasedobviously per year from 1995, with the peak in 2011. Among145 different herbal formulae tested, the most popular prescribedherbal formulae were Longdan Xiegan decoction andTongqiao Huoxue decoction, and the top three frequently usedChinese herbs were Rhizoma Chuanxiong, Radix Bupleuri andRadix Puerariae Lobatae. The most frequently reported outcomewas improvement of hearing in 286 (95.7%), followed byimprovement of tinnitus (139, 46.5%), improvement of dizziness(99, 33.1%). Among the 150 RCTs, randomization methodswere described in only 12 trials (8.0%). No trial reported allocationconcealment and only four mentioned blinding. Among146 RCTs (97.3%) and 37 CCTs (88.1%) reporting improvementof hearing as the outcome measurement, all showed significantdifference favoring CHM. Of 16 trials reporting adverseevents, only five trials reported mild adverse events related toCHM and the remaining stated that none had occurred.Conclusion: The quantity of clinical research on CHM forISSHL is substantial, but methodological quality of RCTs isgenerally suboptimal. Future clinical studies would need toreport structurally and based on the CONSORT and TRENDStatements. Quality of life, adverse events, depression andanxiety should be addressed as outcome measures.