Hearing aids may help delay dementia, depression in elders

For older adults, hearing aids may delay some forms of mental and physical decline associated with hearing loss and aging, a U.S. study suggests.

Among people who’d been diagnosed with hearing loss, those who used hearing aids were up to 18% less likely to be diagnosed with dementia, depression or fall-related injuries over the next three years, compared to people not using the devices, researchers report in the Journal of the American Geriatrics Society.

More than 27 million older Americans live with hearing loss. But only 12.3% of those with a formal diagnosis get hearing aids, the authors note.

“Prevalence of hearing loss is estimated to increase as our population grows older, and we know there are strong associations between uncorrected hearing loss and conditions such as Alzheimer’s disease or dementia,” lead author Dr. Elham Mahmoudi of the University of Michigan in Ann Arbor told Reuters Health by email.

Past research has linked prolonged sensory deprivation - such as loss of hearing - with social isolation and cognitive decline, the study team notes. Hearing loss has also been tied to depression, anxiety and balance trouble with increased risk of falls.

Using insurance claims data, Mahmoudi’s team studied 114,862 people age 66 and older with hearing loss.

“For each patient, data was collected over four years - one year before they were diagnosed with hearing loss, and three years after,” Mahmoudi said. “This was done to ensure the patient had not been diagnosed with Alzheimer’s disease or dementia, depression or anxiety, and injuries from falls in the year before their diagnosis.”

Only 12.3% of the study subjects used hearing aids, the authors found. Hearing aid use was more common among men (13.3%) than women (11.3%), and among non-Hispanic whites (13.6%) compared to black (9.8%) or Hispanic (6.5%) people.

The gender and race differences are significant, the authors note, because the cognitive conditions being studied are more common among women than men, and among African-Americans compared to whites.

Hearing aid use was highest in north-central states at almost 37%, and lowest, at 6%, in the mountain states.

While everyone in the study had health insurance, hearing aids are typically not covered or only partly covered, and the cost falls on the individual, the study team points out. On average, hearing aids cost between $2,000 and $7,000.

“We not only need to advocate for insurance coverage for hearing aids, but also educate the public about the risks of uncorrected hearing loss,” Mahmoudi said.

The aging U.S. population makes this study significant, noted Dr. Linda McEvoy of the University of California, San Diego, who wasn’t involved in the research.

The study lacked data on patients’ education levels, socioeconomic status or lifestyle that could influence the risks for dementia and other study outcomes. This, McEvoy said, is an important limitation.

“If hearing aid users in the current study have higher levels of education than non-users, then some of the protective associations of using the aid may be the effect of education, not the hearing aids,” McEvoy said in an email.

The study wasn’t designed to determine how hearing aids might reduce risk for physical and mental decline, and randomized clinical trials to test if hearing aids have this protective effect are needed, the study team notes.

Until then, Mahmoudi believes, it would help to make hearing aids more affordable.

“Beyond the costs, low prevalence of hearing aid use has been linked to complexity of the hearing-care system in the U.S., stigma, and poor perceived benefit and need,” she said. “People also do not have a single point of contact.”

Although hearing aids are expensive, she noted, “the costs of the conditions they could prevent or delay are substantially more expensive.”

McEvoy agrees.

“The costs of caring for cognitively-impaired older adults are high. If hearing loss contributes to that risk, then hearing aids may be an easily implemented solution to reduce some of that burden on our healthcare system.”

SOURCE: Journal of the American Geriatrics Society, online September 4, 2019.