Clinical Trial: Prevention of Noise-induced Hearing Loss

Study Status: Not yet recruiting
Recruit Status: Not yet recruiting
Study Type: Interventional

Official Title: Zonisamide and Methylprednisolone to Prevent Noise-induced Temporary Hearing Loss

Brief Summary:

Noise-induced hearing loss affects an estimated 5% of the worldwide population, with 30-40 million Americans exposed to hazardous sound or noise levels regularly. Sources of noise may be occupational, blast noise, or recreational. Trauma to the inner ear can occur through transient hearing loss or permanent hearing loss. Although hearing recovers after temporary transient hearing loss, growing evidence suggests that repeated temporary transient hearing loss may lead to a permanent hearing loss. Currently, there are no treatments and there are no known medications that can be used clinically to prevent noise-induced hearing loss in humans.

The long-term goal of this research is to find medications that can prevent noise-induced hearing loss. The purpose of the present pilot study is to evaluate zonisamide and methylprednisolone as medications to prevent temporary transient hearing loss in humans.

Detailed Summary:

Noise-induced hearing loss (NIHL) affects an estimated 5% of the worldwide population, with 30-40 million Americans exposed to hazardous sound or noise levels regularly. Sources of noise may be occupational (e.g., manufacturing, construction), blast noise (e.g., firearms or explosions), or recreational (e.g., loud music, power tools). Trauma to the inner ear can occur through transient hearing loss (temporary threshold shifts, TTS) or permanent hearing loss (permanent threshold shift, PTS). Although hearing recovers after a TTS in about 24-48 hours, growing evidence suggests that repeated TTS may lead to PTS. Both TTS and PTS lead to a decrease in hearing thresholds at 3000 to 6000 Hz.

Currently, there are no treatments for human NIHL although this is an area of active investigation. Protection against NIHL consists of limiting noise exposure through Occupational Safety and Health Administration (OSHA) limits to occupational noise and the wearing of hearing-protection devices (e.g., ear muffs or earplugs). There are no known medications that can be used clinically to prevent NIHL in humans.

LePrell and colleagues have successfully established a protocol for inducing TTS using digitally-modified pop or rock music. This model of experimentally-induced TTS was intended to provide an ethical way of testing medications that might prevent NIHL.

In a mouse model, Bao and colleagues were able to use zonisamide, an anti-epileptic medication approved for the treatment of partial seizures, and methylprednisolone, a glucocorticoid medication, to protect against noise-induced PTS. The long-term goal of this research is to find medications that can prevent NIHL. The goal of the present pilot study is to evaluate zonisamide and methylprednisolone as medications to prevent TTS in humans. Sponsor: Washington University School of Medicine

Current Primary Outcome: Pure Tone Thresholds [ Time Frame: 15 minutes post-music exposure ]

Original Primary Outcome: Same as current

Current Secondary Outcome:

• DPOAE [ Time Frame: visit 2, pre-music exposure; visit 3-one week after music exposure ]
  Distortion-product otoacoustic emissions (DPOAE) will be used as a secondary auditory outcome. A tinnitus questionnaire (Tinnitus Handicap Inventory) will be used to measure the secondary outcome of tinnitus, which frequently accompanies TTS.
• Pure tone thresholds [ Time Frame: 1 hr 15 min, 2 hr 15 min, and 3 hr 15 min post exposure. ]
  This outcome measures recovery of hearing after loud music exposure

Original Secondary Outcome: Same as current

Information By: Washington University School of Medicine

Dates:
Date Received: January 23, 2014
Date Started: June 2017
Date Completion: January 2020
Last Updated: November 1, 2016
Last Verified: November 2016