Take care of your senses
About one third of older adults have some form of vision problems or loss by age 65, and nearly 50% of people older than 75 have disabling hearing loss. Anosmia, which is the medical term for the decline or loss of smell, can also be a significant blow to quality of life. Still, for most older adults, these common signs of aging don’t affect cognitive health.
Too many older adults consider sensory decline to be something that they must learn to live with, yet there are treatment options available. Scientists are studying whether the risk of cognitive problems can be reduced when these conditions are treated — with glasses, eye surgery, hearing aids, or other health care approaches. Read on to learn how NIA-funded investigators are finding new insights into how the eyes, ears, and nose might be windows into our overall cognitive health.
Alison Abraham, Ph.D., M.S., M.H.S., associate professor of epidemiology and ophthalmology at the University of Colorado School of Public Health, has long studied the relationship between the eyes and the brain. She is a principal investigator with the NIA-funded Eye Determinants of Cognition (EyeDOC) Study.
Abraham has a family history of vision problems that has fueled her personal interest in how vision loss affects emotional well-being, physical functioning, social interaction, and brain health. In her work, she collaborates with community groups and care providers on strategies for increasing routine vison screening and broadening access to vision care for older adults.
Abraham’s research focuses on the retina, the area at the rear of the eyeball that relays visual information through the optic nerve to the brain. “In the womb, the development of the retina and the brain are closely linked,” said Abraham.
In the EyeDOC study, Abraham uses a noninvasive imaging method called optical coherence tomography (OCT) to examine the retina. OCT is currently used to diagnose and manage diseases, including diabetes-related retinopathy and glaucoma. Compared to more intrusive brain imaging tests such as MRIs or PET scans, OCT provides an easier, less expensive way to learn about the health, thickness, and architecture of retinal nerves and blood vessels. Initial studies with OCT have shown obvious differences in retinal nerve fiber thickness between cognitively healthy older adults and people with Alzheimer’s disease and related dementias.
Abraham is continuing studies in this area and is hopeful that OCT could be repurposed to develop retinal biomarkers for earlier screening of people at risk for cognitive impairment. Other researchers found that cataract extraction was significantly associated with a lower risk of dementia development.