New research finds link between impaired vision, hearing, and cognition

Experts at a prestigious medical conference hosted by the American Geriatrics Society (AGS) and funded by the National Institute on Aging (NIA) hope their work--reported today in the Journal of the American Geriatrics Society--will have colleagues seeing eye-to-eye on an important but under-researched area of health care: The link between impaired vision, hearing, and cognition (the medical term for our memory and thinking capabilities, which are impacted as we age by health concerns like dementia and Alzheimer's disease). With vision and hearing loss already affecting up to 40 percent of older adults--and with one-in-ten older people already living with Alzheimer's disease--the conference reviewed the current state of science regarding how these common health challenges might be connected, why the answer might matter, and what can be done to reduce sensory and cognitive impairments to preserve our health for as long as possible.

"As we live longer, we know that sensory and cognitive impairments will become more prevalent," said Heather Whitson, MD, MHS, Associate Professor of Medicine & Ophthalmology at Duke University Medical Center and one of the lead researchers for the AGS-NIA conference convened in 2017. "While we know a great deal about these impairments individually, we know less about how they are related--which is surprising, since impaired hearing and vision often go hand-in-hand and are associated with an increased risk for cognitive trouble."

One obstacle to optimizing sensory and cognitive health is our poor understanding of the two-way street connecting both. For example, we know the brain relies on sensory input to understand our environment and make decisions. Researchers also know that cognitive processes--such as connections in the brain that allow us to locate visual targets--guide our visual and auditory attention. Yet we have a limited understanding of how these inter-related processes are affected by age-related changes in the brain, eyes, and ears.

Is the connection between sensory impairment and cognitive decline linear, with one health concern leading to the other, or is it cyclical, reflecting a more complex connection? AGS-NIA conference attendees think answers to these questions are critical, which is why their conference report maps the state of sensory and cognitive impairment research while also outlining important priorities for future scholarship and clinical practice. These include answering questions tied to the mechanics, measurement, and management of impairments: