Merck Manuals Answers Common Questions About Hearing Loss and Dementia

RAHWAY, N.J., May 21, 2026 /PRNewswire/ -- A growing body of evidence in recent years points to a connection between hearing loss and dementia later in life.

In a new editorial from MerckManuals.com, Dr. Larry Lustig, Columbia University Medical Center and New York Presbyterian Hospital Hearing Loss and Deafness, Inner Ear Disorders, answers some of the most common questions from patients about the connection, including what people can do to protect their hearing.

What does the research say about hearing loss and dementia?

Research has suggested that among aging populations, the connection between hearing loss and dementia is stronger than we would expect by random chance.

It's important to note that this connection does not necessarily mean that hearing loss causes dementia, says Lustig. However, researchers are finding that the presence of hearing loss appears to accelerate existing – or emerging – dementia.

Hearing loss, particularly severe hearing loss, can also lead to a person becoming more withdrawn and socially isolated, which can is known to also increase the risk for dementia.

What causes hearing loss?

Hearing loss falls into two broad categories: conductive hearing loss and sensorineural hearing loss, says Lustig. Conductive hearing loss occurs when something blocks sound from reaching the sensory structures in the inner ear, such as wax or fluid.

With sensorineural hearing loss, sound reaches the inner ear but cannot be effectively translated into nerve impulses. Conductive hearing loss can often be treated by removing whatever is blocking the sound, whereas sensory hearing loss generally cannot be reversed. Noise and aging are both common causes of sensorineural hearing loss, says Lustig.

How does someone know they have hearing loss?

Certain kinds of hearing loss are cause for immediate concern, says Lustig. Hearing loss in only one ear or hearing loss that comes with neurologic abnormalities like numbness, loss of balance, or difficulty chewing or speaking warrants seeing a doctor immediately.

For hearing loss that develops gradually, many people struggle to admit they are experiencing it. Their first response is often "other people need to speak up," says Lustig. Patients may first notice difficulty hearing when trying to follow a conversation in noisy situations.

How can people treat hearing loss?

Many causes of hearing loss have no cure, and treatment involves compensating for the hearing loss with hearing aids and various other assistive strategies and technologies, says Lustig.

At any time and at any age, people can stop behaviors that lead to hearing loss and can take hearing protection seriously, says Lustig. That means using earplugs at loud events or work environments. It also means keeping headphones at a safe volume.

How should people talk to their doctor about the connection between hearing loss and dementia?

Even though research points to a connection between hearing loss and dementia, each is a distinct condition requiring its own treatment and approaches, says Lustig. An audiologist can address hearing loss, but any cognitive decline requires a visit to a neurologist for a full evaluation.

Lustig emphasizes that addressing hearing loss can improve relationships with loved ones and enhance quality of life now and into the future.

To read more of Lustig's insights on hearing loss and dementia, visit this editorial on MerckManuals.com.

About The Merck Manuals and MSD Manuals

First published in 1899 as a pocket-sized reference for physicians and pharmacists, The Merck Manual has evolved into one of the world's most trusted and widely-used medical resources. Today, it serves professionals and consumers alike with expert-authored, regularly updated medical content. Available in 16 languages and reaching nearly 250 countries, The Manuals offer far more than text. The website and mobile apps feature an ever-growing collection of videos, podcasts, infographics, and interactive 3D models designed for medical professionals, students, veterinarians, and curious consumers. For over a century, The Merck Manual has been fully committed to making reliable medical knowledge accessible to everyone, everywhere. Access The Manuals online in the United States and Canada at MerckManuals.com, and worldwide at MSDManuals.com.

About Merck

At Merck, known as MSD outside of the United States and Canada, we are unified around our purpose: We use the power of leading-edge science to save and improve lives around the world. For more than 130 years, we have brought hope to humanity through the development of important medicines and vaccines. We aspire to be the premier research-intensive biopharmaceutical company in the world – and today, we are at the forefront of research to deliver innovative health solutions that advance the prevention and treatment of diseases in people and animals. We foster a diverse and inclusive global workforce and operate responsibly every day to enable a safe, sustainable and healthy future for all people and communities. For more information, visit www.merck.com and connect with us on X (formerly Twitter), Facebook, Instagram, YouTube and LinkedIn.

SOURCE The Merck Manuals