Understanding the Consequences of Recreational Noise Exposure

Sponsor

University of Nottingham (Other)

Overall Status

Recruiting

CT.gov ID

NCT05076344

Collaborator

University of Manchester (Other), Nottingham University Hospitals NHS Trust (Other), National Institute for Health Research Nottingham Biomedical Research Centre (Other)

200

Enrollment

Locations

46.4

Anticipated Duration (Months)

100

Patients Per Site

2.2

Patients Per Site Per Month

Study Details

Study Description

Brief Summary

The aim of this study is to determine whether measures derived from Magnetic Resonance Imaging (MRI) scans, and clinical and behavioural measures of hearing loss, in the peripheral and central auditory system (ranging from the cochlear nerve through the auditory brainstem to the auditory cortex) are associated with age and history of noise exposure in otherwise healthy adult humans.

Condition or Disease	Intervention/Treatment	Phase
Hearing Loss Hearing Loss, Noise-Induced

Detailed Description

Noise exposure is the main cause of preventable hearing loss worldwide. Noise exposure occurs in the workplace, such as in noisy factories, and recreationally through the use of personal music players and attendance at nightclubs and live music events.

Hearing loss is usually diagnosed using pure tone audiometry, which measures the sensitivity of the ear to quiet sounds by determining the levels of tones that can just be heard at several test frequencies. Until recently, it had been assumed that hearing loss results mainly from damage to the sensory hair cells in the cochlea, the part of the ear that converts acoustic vibrations into electrical impulses in the cochlear nerve (CN). However, recent results from animal studies suggest that even moderate noise exposure can cause substantial damage to the CN, without any noticeable damage to the hair cells. Crucially, these results suggest that such damage does not immediately affect sensitivity to quiet sounds, but may exacerbate the effects of ageing.

Hearing loss is a huge problem. Substantial numbers of people, millions in the United Kingdom (UK) alone, are routinely exposed to significant levels of occupational and/or recreational noise. A large UK study found that one in seven adults aged 17-30 years reported "great difficulty" hearing speech in noisy backgrounds, while only one in fifty had impaired sensitivity as measured by pure tone audiometry. Hearing loss can lead to social isolation, depression, and is likely to be predictive of more severe hearing loss in old age. Recent studies suggest that hearing loss also reduces quality of life and is a risk factor for dementia.

This study is part of a programme grant conducted from April 2021 to March 2026 by The University of Manchester and The University of Nottingham. The overall aim of the programme is to understand the consequences of recreational noise exposure through improvement of the understanding of the contribution of CN damage to listening difficulties and audiometric losses.

The primary research questions are:

How does auditory pathway integrity vary with noise exposure, audiometric / outer hair cell (OHC) loss, and age?
How do auditory pathway integrity, audiometric loss, and OHC loss relate to listening difficulties? The secondary research question is to address how MRI measures relate to electrophysiological measures of auditory pathway integrity.

All participants will undergo the following non-invasive examinations:

Extended high frequency audiometry to 16 kHz.
Distortion Product Otoacoustic Emissions (DPOAEs): DPOAEs to 10.5 kHz.
Middle Ear Muscle Reflex (MEMR): using a broadband contralateral elicitor and a click probe.
Auditory Brainstem Response (ABR) to assess cochlear synaptopathy and central neural function. The ABR will be elicited with high-pass clicks.
Speech in noise: A masked speech test will comprise verbal stimuli presented through headphones. The signal-to-background ratio will be varied adaptively to determine reception threshold.
The Auditory Digit Span test to assess both forward and backward recall as a measurement of short term memory and working memory.
The Tinnitus Functional Index to assess the severity of tinnitus.
The Noise Exposure Structured Interview (NESI) to assess the lifetime noise exposure.
MR Neurography using structural Magnetic Resonance Imaging to visualise the cochlear nerve and measure the diameter/cross-sectional area.
High-resolution diffusion tensor imaging (DTI) to determine the apparent diffusion coefficient (ADC) and fractional anisotropy (FA) in the cochlear nerve.
Whole-brain DTI to measure the apparent diffusion coefficient (ADC) and fractional anisotropy (FA) in the ascending auditory pathway and auditory cortex.
High spatial resolution quantitative T1 mapping will be used to assess myelination in the ascending auditory pathway and auditory cortex.
High spatial resolution T1 weighted imaging will be used to assess morphometry in the ascending auditory pathway and auditory cortex.
Resting State Functional MRI, lasting 15 minutes, with eyes open and relaxed fixation, will be used to assess the functional connectivity in the ascending auditory pathway and auditory cortex.

Study Design

Study Type:

Observational

Anticipated Enrollment :

200 participants

Observational Model:

Case-Control

Time Perspective:

Cross-Sectional

Official Title:

Understanding the Consequences of Recreational Noise Exposure

Actual Study Start Date :

May 19, 2022

Anticipated Primary Completion Date :

May 18, 2025

Anticipated Study Completion Date :

Mar 31, 2026

Arms and Interventions

Arm	Intervention/Treatment
Group 1: young adults 50 adults aged 18-19 years, with low lifetime noise exposure and audiometric thresholds in the normal range for their age.
Group 2: older adults with low noise exposure 50 adults aged 30-50 years, with low lifetime noise exposure and audiometric thresholds in the normal range for their age.
Group 3: older adults with high noise exposure 50 adults aged 30-50 years, with high lifetime noise exposure and audiometric thresholds in the normal range for their age.
Group 4: older adults with suspected noise-induced hearing loss 50 adults aged 30-50 years, with high lifetime noise exposure and audiometric thresholds above the normal range for their age.

Outcome Measures

Primary Outcome Measures

Auditory nerve health [Baseline]
Auditory nerve diameter and/or surface area
Auditory nerve health [Baseline]
Diffusion measure in the auditory nerve (fractional anisotropy or apparent diffusion coefficient)

Secondary Outcome Measures

Anatomical measure of the ascending auditory pathway [Baseline]
Diffusion measure in the ascending auditory pathway (fractional anisotropy or apparent diffusion coefficient)
Anatomical measure of the ascending auditory pathway [Baseline]
Myelination measure in the ascending auditory pathway
Anatomical measure of the ascending auditory pathway [Baseline]
Morphometry measure in the ascending auditory pathway
Functional measure of the ascending auditory pathway [Baseline]
Resting state functional connectivity measure in the ascending auditory pathway

Eligibility Criteria

Criteria

Ages Eligible for Study:

18 Years to 50 Years

Sexes Eligible for Study:

All

Accepts Healthy Volunteers:

Yes

Inclusion Criteria:

Ability to give informed consent in English
In the age range stipulated for the group, i.e. 18-19 inclusive for group 1 and 30-50 inclusive for groups 2 - 4.
Audiometric thresholds in the range stipulated for the group, i.e. in the normal range for their age group for groups 1 - 3 and outside the normal range for their age group for group 4.
Noise exposure in the range stipulated for the group, as determined by the NESI, i.e. less than 15 units for groups 1 - 2 and 15 or more units for groups 3 - 4.

Exclusion Criteria:

Contraindications for MRI
Motor impairment (for example, cerebral palsy)
Cognitive impairment (for example, dementia or brain injury)
Health conditions indicative of peripheral neuropathy (e.g. Type 1 diabetes).

Contacts and Locations

Locations

	Site	City	State	Country	Postal Code
1	Hearing Theme, NIHR Nottingham Biomedical Research Centre, Ropewalk House, 113 The Ropewalk	Nottingham	Nottinghamshire	United Kingdom	NG1 5DU
2	Sir Peter Mansfield Imaging Centre, University of Nottingham	Nottingham	Nottinghamshire	United Kingdom	NG7 2RD