The Protective Effects of D-Methionine in Noise-Induced Hearing Loss / 听力学及言语疾病杂志

ABSTRACT

Objective To evaluate the protective effects of oral administration of D-methionine tablets on noise-induced hearing loss.Methods A total of 203 volunteers were recruited and randomly divided into two groupsexperimental group (n=113)and control group (n=90).The subjects in the experimental group received oral administration of D-methionine tablets(1 500 mg/day)and those in the control group received placebo for 3 days before impulse noise exposure.The routine audiometric evaluation and ABR testing were performed and recor-ded 1 day and 7 days post- noise exposure.The statistical analysis was carried out with SPSS 11.0.ResuIts The changes of hearing in all participators were observed after noise exposure.The results were as followThe hearing thresh-olds at three time points were 40.5±9.3,51.7±12.3,44.1±11.4 dB nHL in experimental group and 41.5±8.9,62.4± 13.7,47.6±12.5 dB nHL in control group,respectlvely;the ABR I-V IPLs at three time points were 3.72±0.21 ms, 3.99±0.36 ms,3.82±0.25 ms in experimental group,while 3.71±0.22 ms,4.45±0.37 ms,3.85±0.34 ms in control group,respectively.There were statistically significant differences between the two groups.ConcIusion The oral adminis-tration of D-methionine tablets pre noise exposure can protect against noise-induced hearing loss.