(WISH) — More than 55 million people in the world live with dementia.

As researchers try to identify the onset of the disease, they’ve found that people’s sense of sight and hearing may play a key role.

Dr. Cecelia Lee, an ophthalmologist for the University of Washington School of Medicine, and her colleagues studied data on more than 3,900 people. They found that people with diabetic retinopathy, glaucoma, and macular degeneration had about a 40% higher risk of developing Alzheimer’s disease.

Another recent study published in the journal JAMA Ophthalmology found that people with untreated visual impairments were significantly more likely to develop dementia.

Another study suggests a link between hearing loss and dementia risk, and notes hearing aids could cut cognitive decline in half.

News 8’s Brittany Noble has the details in Tuesday’s Health Spotlight.

This story was created from a script aired on WISH-TV. Health Spotlight is presented by Community Health Network.