Trial Outcomes & Findings for Does Sound Conditioning Protect Against Temporary Hearing Damage (NCT NCT03878875)

NCT ID: NCT03878875

Last Updated: 2024-12-12

Results Overview

Extended Frequency (EF) PTA with results measured in dBHL where higher values mean worse hearing thresholds. Hearing thresholds were measured in the two sessions (unfortunately session three was not completed). A single dB HL value was calculated by averaging results across participants in each session (Extended frequency audiometry (EFA) comprised of averaging 2-16 kHz).

• Recruitment status: COMPLETED
• Target enrollment: 32 participants
• Primary outcome timeframe: 35 minutes per session
• Results posted on: 2024-12-12

Participant Flow

Participant milestones

Measure	High Noise Exposure One group with previous exposure i.e. nightclubs ++ Session One Test Battery: Prior to noise exposure: Test battery - High-frequency audiometry, Distortion Product Otoacoustic Emissions, Middle Ear Muscle Reflex, Speech-in-Noise test, Tinnitus Functional Index (Around 35 minutes with breaks if required) Session Two Test Battery: Exposure at single loud music event (Important that this is part of participants' normal recreational routine, and specifically require that attendance is not prompted by participation in this study): Participants to use sound level meter provided from the Audiology Department at Charing Cross Hospital to measure sound levels inside the loud event. Morning after exposure: Repeat test battery from session one - Ideally as soon as event is over. Session Three Test Battery: 1 week later (recovery): Repeat test battery.	Low Noise Exposure Group with less exposure measured through NESI Session One Test Battery: Prior to noise exposure: Test battery - High-frequency audiometry, Distortion Product Otoacoustic Emissions, Middle Ear Muscle Reflex, Speech-in-Noise test, Tinnitus Functional Index (Around 35 minutes with breaks if required) Session Two Test Battery: Exposure at single loud music event (Important that this is part of participants' normal recreational routine, and specifically require that attendance is not prompted by participation in this study): Participants to use sound level meter provided from the Audiology Department at Charing Cross Hospital to measure sound levels inside the loud event. Morning after exposure: Repeat test battery from session one - Ideally as soon as event is over. Session Three Test Battery: 1 week later (recovery): Repeat test battery.
Overall Study STARTED	16	16
Overall Study COMPLETED	16	16
Overall Study NOT COMPLETED	0	0

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

Race and Ethnicity were not collected from any participant.

Baseline characteristics by cohort

Measure	High Noise Exposure n=16 Participants Session 1 Test Battery: Prior to noise exposure: Test battery - High-frequency audiometry, Distortion Product Otoacoustic Emissions, Middle Ear Muscle Reflex, Speech-in-Noise test (\~35min with breaks if req) EFA (\~8min), 0.25-16 kHz: Participants will be asked to press the button when they hear a sound through the headphones in a soundproof booth. DPOAE (\~5min), 0.5-10 kHz: Small tip will be placed in participants' ear and they will hear a sound. The tip measures a response from hair cells in the cochlea and they will not need to do anything. MEMR (\~8min), 4 kHz: A small tip placed in both ears and again a sound heard, however, this sound will gradually get louder until an involuntary muscle reflex is noted. Speech-in-Noise Test (\~5min): Participants asked to repeat back a list of words as best as they can. Tinnitus: Participants were also asked if they experience any tinnitus i.e. bilateral, lasting \>5min. Reported as Y/N Session 2: Exposure at single loud music event (Important that this is part of participants' normal recreational routine, and specifically require that attendance is not prompted by participation in this study): Participants to use sound level meter provided from the Audiology Department at Charing Cross Hospital or sound level meter applications to measure sound levels inside the loud event. Morning after exposure: Repeat test battery from session 1 - Ideally as soon as event is over. Session 3: 1 week later (recovery): Repeat test battery.	Low Noise Exposure n=16 Participants Session 1 Test Battery: Prior to noise exposure: Test battery - High-frequency audiometry, Distortion Product Otoacoustic Emissions, Middle Ear Muscle Reflex, Speech-in-Noise test (\~35min with breaks if req) EFA (\~8min), 0.25-16 kHz: Participants will be asked to press the button when they hear a sound through the headphones in a soundproof booth. DPOAE (\~5min), 0.5-10 kHz: Small tip will be placed in participants' ear and they will hear a sound. The tip measures a response from hair cells in the cochlea and they will not need to do anything. MEMR (\~8min), 4 kHz: A small tip placed in both ears and again a sound heard, however, this sound will gradually get louder until an involuntary muscle reflex is noted. Speech-in-Noise Test (\~5min): Participants asked to repeat back a list of words as best as they can. Tinnitus: Participants were also asked if they experience any tinnitus i.e. bilateral, lasting \>5min. Reported as Y/N Session 2: Exposure at single loud music event (Important that this is part of participants' normal recreational routine, and specifically require that attendance is not prompted by participation in this study): Participants to use sound level meter provided from the Audiology Department at Charing Cross Hospital or sound level meter applications to measure sound levels inside the loud event. Morning after exposure: Repeat test battery from session 1 - Ideally as soon as event is over. Session 3: 1 week later (recovery): Repeat test battery.	Total n=32 Participants Total of all reporting groups
Age, Categorical <=18 years	0 Participants n=16 Participants	0 Participants n=16 Participants	0 Participants n=32 Participants
Age, Categorical Between 18 and 65 years	16 Participants n=16 Participants	16 Participants n=16 Participants	32 Participants n=32 Participants
Age, Categorical >=65 years	0 Participants n=16 Participants	0 Participants n=16 Participants	0 Participants n=32 Participants
Sex: Female, Male Female	8 Participants n=16 Participants	8 Participants n=16 Participants	16 Participants n=32 Participants
Sex: Female, Male Male	8 Participants n=16 Participants	8 Participants n=16 Participants	16 Participants n=32 Participants
Race and Ethnicity Not Collected	—	—	0 Participants Race and Ethnicity were not collected from any participant.

PRIMARY outcome

Timeframe: 35 minutes per session

Population: For all parametric measures, participants were grouped into exposure and regression analysis assessed the group effect on the dependent variable. A range of categorical and continuous independent variables were controlled for against the dependent variable. Session three was excluded and not collected due to COVID-19.

Extended Frequency (EF) PTA with results measured in dBHL where higher values mean worse hearing thresholds.

Hearing thresholds were measured in the two sessions (unfortunately session three was not completed). A single dB HL value was calculated by averaging results across participants in each session (Extended frequency audiometry (EFA) comprised of averaging 2-16 kHz).

Outcome measures

Measure	High Noise Exposure n=16 Participants Session 1 Test Battery: Prior to noise exposure: Test battery - High-frequency audiometry, Distortion Product Otoacoustic Emissions, Middle Ear Muscle Reflex, Speech-in-Noise test (\~35min with breaks if req) EFA (\~8min), 0.25-16 kHz: Participants will be asked to press the button when they hear a sound through the headphones in a soundproof booth. Session 2: Exposure at single loud music event where participants used a sound level meter or sound level meter applications to measure sound levels inside the loud event. Morning after exposure: Repeat test battery from session 1 - Ideally as soon as event is over.	Low Noise Exposure n=16 Participants Session 1 Test Battery: Prior to noise exposure: Test battery - High-frequency audiometry, Distortion Product Otoacoustic Emissions, Middle Ear Muscle Reflex, Speech-in-Noise test (\~35min with breaks if req) EFA (\~8min), 0.25-16 kHz: Participants will be asked to press the button when they hear a sound through the headphones in a soundproof booth. Session 2: Exposure at single loud music event where participants used a sound level meter or sound level meter applications to measure sound levels inside the loud event. Morning after exposure: Repeat test battery from session 1 - Ideally as soon as event is over.
PTA (EF) Session 1	7.06 dB HL Standard Deviation 8.15	8.94 dB HL Standard Deviation 5.46
PTA (EF) Session 2	7.94 dB HL Standard Deviation 8.35	12.19 dB HL Standard Deviation 6.45

PRIMARY outcome

Timeframe: 35 minutes per session

Population: For all parametric measures, participants were grouped into exposure and regression analysis assessed the group effect on the dependent variable. A range of categorical and continuous independent variables were controlled for against the dependent variable. Session three was excluded and not collected due to COVID-19.

Distortion Product Otoacousic Emissions (DPOAE), DPOAEs were recorded bilaterally (at 0.5, 1, 1.5, 2, 3, 4, 5, 6, 8 and 10 kHz) using the Otometrics Madsen Capella2. A daily check was performed in a 2 cc test cavity and tester's own ear to verify suitable recordings and ensure the probe was providing true responses. Measure results in the two sessions (unfortunately session three was not completed). DPOAE measurements were separated into distortion product (DP - dB SPL) and signal-to-noise ratio (SNR - dB) and averaged from 2-10 kHz. A single value was calculated by averaging results across participants in each session.

Outcome measures

Measure	High Noise Exposure n=16 Participants Session 1 Test Battery: Prior to noise exposure: Test battery - High-frequency audiometry, Distortion Product Otoacoustic Emissions, Middle Ear Muscle Reflex, Speech-in-Noise test (\~35min with breaks if req) EFA (\~8min), 0.25-16 kHz: Participants will be asked to press the button when they hear a sound through the headphones in a soundproof booth. Session 2: Exposure at single loud music event where participants used a sound level meter or sound level meter applications to measure sound levels inside the loud event. Morning after exposure: Repeat test battery from session 1 - Ideally as soon as event is over.	Low Noise Exposure n=16 Participants Session 1 Test Battery: Prior to noise exposure: Test battery - High-frequency audiometry, Distortion Product Otoacoustic Emissions, Middle Ear Muscle Reflex, Speech-in-Noise test (\~35min with breaks if req) EFA (\~8min), 0.25-16 kHz: Participants will be asked to press the button when they hear a sound through the headphones in a soundproof booth. Session 2: Exposure at single loud music event where participants used a sound level meter or sound level meter applications to measure sound levels inside the loud event. Morning after exposure: Repeat test battery from session 1 - Ideally as soon as event is over.
DPOAE (DP) DP (2-10 kHz), Session 1	1.25 dB SPL Standard Deviation 5.03	-0.06 dB SPL Standard Deviation 4.86
DPOAE (DP) DP (2-10 kHz), Session 2	1.75 dB SPL Standard Deviation 5.04	-0.88 dB SPL Standard Deviation 4.53

PRIMARY outcome

Timeframe: 35 minutes per session

Population: For all parametric measures, participants were grouped into exposure and regression analysis assessed the group effect on the dependent variable. A range of categorical and continuous independent variables were controlled for against the dependent variable. Session three was excluded and not collected due to COVID-19.

Distortion Product Otoacousic Emissions (DPOAE), DPOAEs were recorded bilaterally (at 0.5, 1, 1.5, 2, 3, 4, 5, 6, 8 and 10 kHz) using the Otometrics Madsen Capella2. A daily check was performed in a 2 cc test cavity and tester's own ear to verify suitable recordings and ensure the probe was providing true responses. Measure results in the two sessions (unfortunately session three was not completed). DPOAE measurements were separated into distortion product (DP - dB SPL) and signal-to-noise ratio (SNR - dB) and averaged from 2-10 kHz. A single value was calculated by averaging results across participants in each session.

Outcome measures

Measure	High Noise Exposure n=16 Participants Session 1 Test Battery: Prior to noise exposure: Test battery - High-frequency audiometry, Distortion Product Otoacoustic Emissions, Middle Ear Muscle Reflex, Speech-in-Noise test (\~35min with breaks if req) EFA (\~8min), 0.25-16 kHz: Participants will be asked to press the button when they hear a sound through the headphones in a soundproof booth. Session 2: Exposure at single loud music event where participants used a sound level meter or sound level meter applications to measure sound levels inside the loud event. Morning after exposure: Repeat test battery from session 1 - Ideally as soon as event is over.	Low Noise Exposure n=16 Participants Session 1 Test Battery: Prior to noise exposure: Test battery - High-frequency audiometry, Distortion Product Otoacoustic Emissions, Middle Ear Muscle Reflex, Speech-in-Noise test (\~35min with breaks if req) EFA (\~8min), 0.25-16 kHz: Participants will be asked to press the button when they hear a sound through the headphones in a soundproof booth. Session 2: Exposure at single loud music event where participants used a sound level meter or sound level meter applications to measure sound levels inside the loud event. Morning after exposure: Repeat test battery from session 1 - Ideally as soon as event is over.
DPOAE (SNR) SNR (2-10 kHz), Session 1	12.94 dB Standard Deviation 4.33	11.63 dB Standard Deviation 4.15
DPOAE (SNR) SNR (2-10 kHz), Session 2	13.13 dB Standard Deviation 4.63	11.19 dB Standard Deviation 3.85

PRIMARY outcome

Timeframe: 35 minutes per session

Population: For all parametric measures, participants were grouped into exposure and regression analysis assessed the group effect on the dependent variable. A range of categorical and continuous independent variables were controlled for against the dependent variable. Session three was excluded and not collected due to COVID-19.

Middle Ear Muscle Reflex (MEMR) measured at 4 kHz bilaterally in dB SPL. A reflex was defined as > 0.02 ml compliance with appropriate morphology free from artefacts. Measure if MEMR is present/raised in the sessions. Averages between ears were also calculated for MEMR to give one result per participant for each session. A single value was then calculated by averaging results across participants in each session.

Outcome measures

Measure	High Noise Exposure n=16 Participants Session 1 Test Battery: Prior to noise exposure: Test battery - High-frequency audiometry, Distortion Product Otoacoustic Emissions, Middle Ear Muscle Reflex, Speech-in-Noise test (\~35min with breaks if req) EFA (\~8min), 0.25-16 kHz: Participants will be asked to press the button when they hear a sound through the headphones in a soundproof booth. Session 2: Exposure at single loud music event where participants used a sound level meter or sound level meter applications to measure sound levels inside the loud event. Morning after exposure: Repeat test battery from session 1 - Ideally as soon as event is over.	Low Noise Exposure n=16 Participants Session 1 Test Battery: Prior to noise exposure: Test battery - High-frequency audiometry, Distortion Product Otoacoustic Emissions, Middle Ear Muscle Reflex, Speech-in-Noise test (\~35min with breaks if req) EFA (\~8min), 0.25-16 kHz: Participants will be asked to press the button when they hear a sound through the headphones in a soundproof booth. Session 2: Exposure at single loud music event where participants used a sound level meter or sound level meter applications to measure sound levels inside the loud event. Morning after exposure: Repeat test battery from session 1 - Ideally as soon as event is over.
MEMR Session 1	88.91 dB SPL Standard Deviation 7.41	88.44 dB SPL Standard Deviation 8.56
MEMR Session 2	91.25 dB SPL Standard Deviation 6.71	90.31 dB SPL Standard Deviation 10.20

PRIMARY outcome

Timeframe: 35 minutes per session

Population: For all parametric measures, participants were grouped into exposure and regression analysis assessed the group effect on the dependent variable. A range of categorical and continuous independent variables were controlled for against the dependent variable. Session three was excluded and not collected due to COVID-19.

Speech in Noise (SiN) Test, Score. The sound field JBL Control One speakers and the Kamplex KM4 sound level meter (SLM) were calibrated via Guymark. Daily checks were conducted to assess speaker reliability when administering QuickSIN (Etymotic Research, 2001) with the signal and noise presented from the same speaker at 0° azimuths. The SLM confirmed speaker calibration and sound levels presented were within tolerances. Measure SiN in the sessions and a single value was calculated by averaging results across participants in each session.

Outcome measures

Measure	High Noise Exposure n=16 Participants Session 1 Test Battery: Prior to noise exposure: Test battery - High-frequency audiometry, Distortion Product Otoacoustic Emissions, Middle Ear Muscle Reflex, Speech-in-Noise test (\~35min with breaks if req) EFA (\~8min), 0.25-16 kHz: Participants will be asked to press the button when they hear a sound through the headphones in a soundproof booth. Session 2: Exposure at single loud music event where participants used a sound level meter or sound level meter applications to measure sound levels inside the loud event. Morning after exposure: Repeat test battery from session 1 - Ideally as soon as event is over.	Low Noise Exposure n=16 Participants Session 1 Test Battery: Prior to noise exposure: Test battery - High-frequency audiometry, Distortion Product Otoacoustic Emissions, Middle Ear Muscle Reflex, Speech-in-Noise test (\~35min with breaks if req) EFA (\~8min), 0.25-16 kHz: Participants will be asked to press the button when they hear a sound through the headphones in a soundproof booth. Session 2: Exposure at single loud music event where participants used a sound level meter or sound level meter applications to measure sound levels inside the loud event. Morning after exposure: Repeat test battery from session 1 - Ideally as soon as event is over.
SiN Session 1	2.38 dB Standard Deviation 2.53	2.94 dB Standard Deviation 2.77
SiN Session 2	1.38 dB Standard Deviation 2.73	2.44 dB Standard Deviation 2.76

PRIMARY outcome

Timeframe: 35 minutes per session

Population: Session three was excluded and not collected due to COVID-19.

Participants were also asked if they experience any tinnitus i.e. bilateral, lasting > 5 minutes. This was reported as Y/N. An increase in underlying tinnitus, no change in underlying tinnitus and newly reported tinnitus was counted for each group in the second session. We aimed to assess the effect of conditioning on tinnitus change (i.e. increasing or not) at session 2, adjusting for tinnitus reported at session 1, age, gender, and event exposure. Session 1: existing underlying tinnitus reported. Session 2: Newly reported tinnitus and increase in underlying tinnitus.

Outcome measures

Measure	High Noise Exposure n=16 Participants Session 1 Test Battery: Prior to noise exposure: Test battery - High-frequency audiometry, Distortion Product Otoacoustic Emissions, Middle Ear Muscle Reflex, Speech-in-Noise test (\~35min with breaks if req) EFA (\~8min), 0.25-16 kHz: Participants will be asked to press the button when they hear a sound through the headphones in a soundproof booth. Session 2: Exposure at single loud music event where participants used a sound level meter or sound level meter applications to measure sound levels inside the loud event. Morning after exposure: Repeat test battery from session 1 - Ideally as soon as event is over.	Low Noise Exposure n=16 Participants Session 1 Test Battery: Prior to noise exposure: Test battery - High-frequency audiometry, Distortion Product Otoacoustic Emissions, Middle Ear Muscle Reflex, Speech-in-Noise test (\~35min with breaks if req) EFA (\~8min), 0.25-16 kHz: Participants will be asked to press the button when they hear a sound through the headphones in a soundproof booth. Session 2: Exposure at single loud music event where participants used a sound level meter or sound level meter applications to measure sound levels inside the loud event. Morning after exposure: Repeat test battery from session 1 - Ideally as soon as event is over.
Tinnitus Session 2	5 participants	7 participants
Tinnitus Session 1	5 participants	1 participants

Adverse Events

High Noise Exposure (16, 8f:8m)

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

Low Noise Exposure (16, 8f:8m)

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Adverse event data not reported

Additional Information

Hemna Santilale

Imperial

Phone: 020

Email: hemna.santilale@nhs.net

Results disclosure agreements

• Principal investigator is a sponsor employee
• Publication restrictions are in place