Investigational Medicinal Products for the Inner Ear: Review of Clinical Trial Characteristics in ClinicalTrials.gov.

BACKGROUND: The previous 30 years have provided information on the mechanisms of cell death in the inner ear after noise exposure, ototoxic drug injury, and during aging, and clinical trials have emerged for all of these acquired forms of hearing loss. Sudden hearing loss is less well understood, but restoration of hearing after sudden hearing loss is also a long-standing drug target, typically using steroids as an intervention but with other agents of interest as well. PURPOSE: The purpose of this review was to describe the state of the science regarding clinical testing of investigational medicinal products for the inner ear with respect to treatment or prevention of acquired hearing loss. DATA COLLECTION AND ANALYSIS: Comprehensive search and summary of clinical trials listed in the National Library of Medicine (www. CLINICALTRIALS: gov) database identified 61 clinical trials. RESULTS: Study phase, status, intervention, and primary, secondary, and other outcomes are summarized for studies assessing prevention of noise-induced hearing loss, prevention of drug-induced hearing loss, treatment of stable sensorineural hearing loss, and treatment of sudden sensorineural hearing loss. CONCLUSION: This review provides a comprehensive summary of the state of the science with respect to investigational medicinal products for the inner ear evaluated in human clinical trials, and the current challenges for the field.

Metformin decreases the risk of sudden sensorineural hearing loss in patients with diabetes mellitus: A 14-year follow-up study.

BACKGROUND: The risk of sudden sensorineural hearing loss associated with metformin use in patients with diabetes mellitus has not been fully examined. STUDY DESIGN: It is a retrospective matched-cohort study. SUBJECTS AND METHODS: We examined the medical records of patients with diabetes mellitus over 18 years old in Taiwan's National Health Insurance Research Database for the period between 1 January 2000 and 31 December 2013, to establish matched cohorts (14,109 with and 42,327 without metformin use) at a ratio of 1:3 by sex, age and index year. RESULTS: We used a Cox regression hazard model to identify risk factors of sudden sensorineural hearing loss during 14 years of follow-up, and the results indicate that a significantly lower percentage of diabetes mellitus patients with metformin use (p = 0.033) developed sudden sensorineural hearing loss compared with those without metformin use (0.21%, 29/14,109 vs 0.32%, 136/42,327). After adjustment for age and other variables [adjusted hazard ratio: 0.630 (95% confidence interval: 0.422-0.941, p = 0.024)], this study also demonstrated that metformin use appeared to reduce the risk of developing sudden sensorineural hearing loss. CONCLUSION: This study demonstrated an association between metformin use and lower incidence of sudden sensorineural hearing loss among patients with diabetes mellitus.

[Acute hearing impairment by extremely high sound pressure levels]. / Akute Gehörschäden durch extrem hohe Schalldruckpegel.

The bulletin for occupational disease no. 2301 in the annex of the Occupational Disease Act, noise-induced hearing impairment, ("Merkblatt zu der Berufskrankheit Nr. 2301 der Anlage zur Berufskrankheiten-Verordnung: Lärmschwerhörigkeit") states that sound events with an intensity exceeding 137 dB (C) may cause immediate mechanical damage to the inner ear. Up to now a distinction has been made between prevention and actual damage potential for the risks caused by sounds with extremely high peak levels. In the field of prevention the unweighted sound pressure peak level of 140 dB, which is now 137 dB(C,peak) according to the LärmVibrationsArbSchV, was applied as the trigger threshold for measures; in contrast actual hearing impairment was not found until 150-160 dB. This article compiles the current state of knowledge and demonstrates that in the area of the reasons mentioned here for acute hearing impairment, no scientifically based new findings exist especially with reference to publications listed in the bulletin.

[Evaluation of the clinical studies of prevention and treatment of sudden deafness in China].

OBJECTIVE: To summarize and evaluate the current situation on sudden deafness in China by retrospective review of the articles appeared in Chinese journals in the past 3 years. METHODS: The terms of sudden deafness and therapy were used to search all of the articles on the therapy of sudden deafness through the Chinese bio-medicine literature data base and Chinese journal net from 2000 - 2002. All of the articles were analyzed according to the standards of evidence-based medicine. RESULTS: One hundred and seventy-six articles were collected. 126 were on the curative effect of medicine, of which 26 (20.6%) based on the diagnosis and therapy standards settled by the otolaryngology branch of Chinese medical association in 1996, 89 (70.6%) were controlled clinical trials and 36 (28.5%) were randomized controlled trials. Most of the articles mentioned the 5 items diagnosis based and not detailed weather hypertension, diabetes and hyperlipemia were excluded. CONCLUSIONS: There are many articles on the therapy of sudden deafness. However, the inconsistent understanding of the prognosis and evaluation and unstuck trial design limited the therapy, research and the standards of literature on sudden deafness to progress further.

[Criteria for the further employment of persons with hearing damage in noise areas (author's transl)]. / Kriterien für den weiteran beruflichen Einsatz gehörgeschädigter Personen im Lämbereich.

The possibility of further employment of workers in noise areas must be judged by the specific criteria of "Principle No. 20" of the Professional Associations. However, in many cases of already existing hearing damage it is possible to avoid a change of working place for the time being and to rate "No objection on health reasons under certain conditions". In cases of noise-induced, already existing hearing loss, a change of working place is generally not necessary if the worker uses ear protectors. There should also be no general objection in cases of pure disturbance of sound conduction. In combined hearing losses and pure labyrinthine deafness not created by noise, it must be supposed as a general rule that the worker is not fit for further working in noise areas. However, in special cases carefully analysed as to anamnesis and development, even a worker with such types of hearing loss might under special precautions be retained in the noise area.