Will hearing aids help an adult with conductive hearing loss?

Hearing Aids for Conductive Hearing Loss

Yes, hearing aids are highly effective for conductive hearing loss and patients with conductive hearing loss derive more benefit from amplification than those with sensorineural hearing loss. 1, 2

Why Hearing Aids Work Well for Conductive Hearing Loss

Conventional air conduction hearing aids are the first-line treatment for mild to moderate conductive hearing loss (20-70 dB HL) and provide precise control for the patient's dynamic range. 1 The fundamental advantage is that conductive hearing loss involves a mechanical problem in sound transmission through the outer or middle ear, while the inner ear (cochlea) and auditory nerve remain intact and functional. 3

Evidence of Superior Benefit

• Patients with conductive hearing loss demonstrate greater improvement with hearing aids compared to those with sensorineural hearing loss when matched for age, sex, and hearing thresholds. 2
• When unaided, individuals with conductive impairment are more disabled than those with sensorineural impairment, but they derive substantially more benefit from amplification. 2
• Hearing aids improve communication ability, social function, and speech understanding while reducing listening effort, fatigue, depression risk, and social isolation. 1

Prescriptive Approach for Conductive Loss

The 75% air-bone gap (ABG) + bone conduction (BC) approach should be used for prescribing amplification, not the 25% ABG + air conduction approach. 4 This is critical because:

• The 75% ABG + BC method prescribes a compression ratio that accurately reflects the amount of sensorineural hearing loss (which is minimal or absent in pure conductive loss). 4
• The 25% ABG + AC approach inappropriately uses air conduction thresholds to determine compression ratio, which is incorrect for conductive hearing loss. 4
• This prescriptive difference has been the standard since 1999 with the NAL-NL1 method. 4

Device Selection Considerations

For conductive hearing loss requiring high output, receiver-in-aid (RIA) behind-the-ear (BTE) hearing aids generally have greater maximum power output (MPO) capabilities than receiver-in-canal (RIC) devices. 4 This becomes particularly important when:

• Large conductive components are present (>40 dB air-bone gap). 4
• Mixed hearing loss combines significant conductive and sensorineural components. 4
• Not all hearing aids have sufficient MPO to support the output requirements for large conductive losses. 4

Alternative Options When Conventional Aids Cannot Be Used

Bone-anchored hearing aids (BAHAs) or osseointegrated bone conductive devices are appropriate surgical options when conventional amplification cannot be used. 1, 5 These are indicated when:

• Reconstructive surgery is not possible (e.g., chronically draining ear, severe congenital malformation). 5
• Unilateral conductive hearing loss requires binaural hearing restoration. 5
• Sound localization and binaural advantage can be restored to levels comparable with normal-hearing individuals. 5

For transient conductive hearing loss (such as post-operative auditory canal tamponade), adhesive bone conduction systems provide safe and effective short-term rehabilitation. 6 These non-invasive devices improve:

• Speech perception in quiet by 46% on average. 6
• Functional hearing gain by 19 dB. 6
• Speech perception in noise by 2.7 dB signal-to-noise ratio. 6

Referral Pathway

Patients with conductive hearing loss should be referred to an audiologist for comprehensive audiometric testing to determine the type and severity of hearing loss before hearing aid fitting. 1 This ensures:

• Accurate differentiation between conductive, sensorineural, and mixed hearing loss. 1
• Appropriate prescriptive targets using the 75% ABG + BC approach. 4
• Selection of devices with adequate MPO capabilities. 4

Common Pitfall to Avoid

Do not delay hearing aid fitting while waiting for medical or surgical treatment of the underlying cause. 7 For example, otitis media with effusion (OME) further compounds conductive hearing loss and negatively affects prescriptive targets, but definitive resolution of OME should never delay amplification device fitting. 7 Prompt treatment of persistent OME should occur concurrently with hearing aid provision. 7