Hearing aids slow cognitive decline in seniors

As the world population ages, the number of people living with dementia and other types of cognitive impairment continues to rise. Studies show the connection between hearing loss and dementia in older adults, and suggest that using hearing aids may help slow the development of cognitive problems.

A research team from Johns Hopkins University, led by Dr. Frank Lin, enrolled nearly 1,000 adults ages 70 to 84 into a clinical trial from two different study populations. Out of all the participants, about 250 healthy older adults came from a long-term study of heart health. People recruited from the heart-health study had more risk factors for developing dementia, including being older and having faster rates of cognitive decline.

All the participants were randomly assigned to one of two interventions. About half received hearing aids and instruction in how to use them. The other half were assigned to a health education program focused on promoting healthy aging. Both groups received follow-up visits every six months to reinforce the training.

Before the start of the study and annually for three years, all participants took a battery of tests to measure cognitive functioning.

People who received the hearing aids reported substantial improvement in communica-tion abilities over the course of the study. Those in the health education group did not experience improvement in hearing and communication.

In the main analysis of all study participants, the researchers saw no difference in the rate of change in cognitive functioning between people who received the hearing aids and those who didn’t. However, when the analysis focused on people from the heart-health study who had a higher risk of dementia, the benefit of the hearing aids was substantial, showing almost 50% reduction in the rate of cognitive decline compared to people in the health education group.

The researchers are continuing to follow the study participants to see how changes in cognition develop over time. They’re also looking at brain scans and data on social engagement to better understand how protecting hearing may prevent cognitive decline in vulnerable older adults.

For more information, visit https://www.nia.nih.gov. —Sharon Reynolds National Institute on Aging

"Hearing loss is very treatable in later life, which makes it an important public health target to reduce risk of cognitive decline and dementia. It is recommended for older adults' general health to have their hearing checked regularly and issues properly addressed."

— Dr. Frank Lin, Johns Hopkins University