Hearing loss and dementia: The overlooked modifiable risk factor in ageing Kiwis

Hearing loss that is not managed is more than a quality-of-life issue - it’s now recognised as one of the most significant modifiable risk factors for dementia in elderlies. With nearly 1 in 3 New Zealanders over 65 experiencing hearing loss, early intervention is not just helpful, it's critical.

Why this matters now

As Aotearoa’s population ages, dementia diagnoses are on the rise. At the same time, many older adults in retirement communities live with untreated hearing loss - often unaware of the broader cognitive risks this poses. A growing body of research from around the world, including recent large-scale studies, confirms hearing loss as a modifiable risk factor for dementia.

The research is clear: Hearing loss doubles dementia risk

• A 2024 Danish study of over 570,000 adults found severe hearing loss increases dementia risk by 20%, while those using hearing aids saw significantly reduced risk.

• A 2022 global review spanning 50 studies and 1.5 million people found a 35% increased risk of dementia and 56% higher risk of Alzheimer’s disease linked to hearing loss.

• Every 10-decibel decrease in hearing raises dementia risk by 16%.

How hearing loss affects the brain

Researchers have identified several biological and social mechanisms that help explain the connection [1]:

• Increased cognitive load: When hearing is difficult, the brain works overtime to understand sounds - leaving less capacity for memory and thinking.

• Sensory deprivation: A lack of auditory input may shrink parts of the brain, including areas linked to memory and language

• Social withdrawal: Hearing loss often leads to isolation, which could increase rates of cognitive decline.

• Delayed diagnosis of dementia: Communication difficulties may mask early signs of dementia, preventing timely care.

The good news: This is a modifiable risk

The most powerful part of the evidence? Hearing loss may be a potentially modifiable risk factor to reduce cognitive decline - and managing hearing loss early makes a measurable difference [2]

• Hearing aid use has been shown to reduce cognitive decline by nearly 50% in older adults at risk of dementia.

• Treating hearing loss can also restore social confidence, improve mood, and help seniors stay engaged longer.

Reaching retirement villages to help preserve memories

At the Deaf and hard of hearing Foundation, we believe no one should face ageing or memory loss alone - especially not due to a preventable condition like hearing loss. That’s why working on expanding our Retirement Villages Outreach Programme which offers:

• Free 15-minute on-site hearing checks

• Educational workshops on hearing and brain health

• Guidance on next steps for treatment and support

Help us reach 140 villages in 2026

This holiday season, we’re on a mission to raise $40,000 to bring our Retirement Village Outreach programme to 140 retirement villages across Aotearoa.

With your support, we can detect hearing loss early, reduce feelings of isolation, help address a modifiable risk for cognitive decline, and improve quality of life for thousands of ageing New Zealanders.

Donate to our appeal

Let’s protect both hearing and memory - for a healthier, more connected ageing journey.

Get involved

• Share this blog with your retirement village community.

• Help us spread the word about the link between hearing loss and dementia.

• Donate today to support early intervention for older adults.