(Reuters Health) - - Hearing aids may lessen the forgetfulness and mental confusion tied to moderate to severe hearing loss, suggests a new study.

“This study is important because it focuses on a risk factor that is amenable to intervention in later life and could potentially postpone cognitive decline,” said Jennifer Deal, the study’s lead author from the Bloomberg School of Public Health at Johns Hopkins University in Baltimore.

She and her colleagues write in the American Journal of Epidemiology that previous studies found a link to an increased risk between hearing loss and cognition problems. Though the underlying cause is still unknown, researchers speculate the two conditions may be linked through inflammation, social isolation or a number of other conditions.

Few studies have focused on whether wearing hearing aids lessen the risk of future cognitive problems, they write. For the new study, they used data from a past study to see if wearing hearing aids provided people with any possible protection against future problems.

The study included 253 people from Maryland with an average age of 77 years. Most of the people had mild, moderate or severe hearing loss.

Most participants were white and all were from one region, which the researchers point out are limitations of the study.

The participants were tested on memory, learning, language and processing speed/attention from 1990 to 1992, 1996 to 1998 and given an intensive cognitive test in 2013.

Overall, the test scores of participants with moderate to severe hearing loss declined over the 20 years. But those participants who reported not wearing a hearing aid experienced the largest decline.

Participants who wore a hearing aid had scores that were only slightly worse after 20 years than people with normal hearing, the researchers report.

Deal cautioned that the hearing aids may not directly protect against cognitive decline.

For example, the devices are not covered by traditional plans under Medicare, the government-run insurance in the U.S. for the elderly and disabled. The results may reflect that people who have hearing aids have larger incomes or take better care of themselves, she told Reuters Health.

“But we also know people who have hearing aids may have them because they have greater amounts of hearing loss,” Deal said.

There are a number of barriers to using hearing aids, she said. Those include the roughly $2,000 to $3,000 cost and the need to learn to use the devices.

“For the majority of older adults, as an out of pocket expense, it really is second to a mortgage or a car, one of the most expensive purchases you can make in your lifetime,” Deal said.

“This shows we really should be treating hearing loss,” said Dr. Alice Holmes, a professor of Audiology at the University of Florida in Gainesville.

Communication training or other audiologic rehabilitation could also offer the help that is critical for an improved quality of life, said Holmes, who was not involved with the new study.

“I think treating the hearing loss can really improve someone’s overall quality of life and not only does it improve that quality of life but also others’ around him,” Holmes told Reuters Health.

SOURCE: bit.ly/1NE8msq American Journal of Epidemiology, online April 4, 2015.