Hearing aids may mitigate dementia risk in adults with hearing loss

Editor’s note: The Lancet Public Health retracted this study on Dec. 12, 2023, due to an error in the output format setting of the researchers’ SAS codes, resulting in errors in the analysis that render the findings “false and misleading,” according to the journal.

Key takeaways:

• People with hearing loss had a 42% increased risk for dementia compared with those without hearing loss.
• Those with hearing loss who used hearing aids had a similar dementia risk as those without hearing loss.

People with hearing loss who did not use hearing aids had an increased risk for dementia compared with those without hearing loss, data show. However, researchers found no increased risk in people with hearing loss who used aids.

Previous research has suggested that mild to severe hearing loss alone is associated with a higher prevalence of dementia in older adults, Fan Jiang, PhD, from the Center for Health Management and Policy Research at Shandong University in China, and colleagues wrote in The Lancet Public Health. Remedies for hearing loss, like hearing aids, could potentially reduce risks for cognitive impairment, they added.

Although hearing aids have been linked to both improved cognitive function and diminished cognitive decline, their association with dementia prevalence “in a real-world context remains unclear” amid inconsistent findings, the researchers wrote.

Thus, Jiang and colleagues conducted a population cohort study to determine potential associations between hearing aid use and dementia risk. Their analysis included data from 437,704 people enrolled in the U.K. Biobank from 2006 to 2010. The participants had a mean age of 56 years, and 53.7% were women.

Of the participants, 25.6% had hearing loss, and 11.7% of them used hearing aids.

Compared with participants without hearing loss, those with hearing loss who did not use hearing aids had a 42% (95% CI, 1.29-1.56) increased risk for all-cause dementia. The researchers observed no increased risk in those with hearing loss who used hearing aids.

Jiang and colleagues estimated that the attributable risk proportion for hearing loss without the use of hearing aids was 29.08%. They also reported that the attributable risk proportions of hearing loss and no hearing aids were higher in women than men for:

• all-cause dementia (35.9% vs. 25.93%);
• Alzheimer’s disease (28.06% vs. 21.88%);
• vascular dementia (43.82% vs. 31.03%); and
• non-Alzheimer’s disease non-vascular dementia (43.5% vs. 25.93%).

When evaluating the roles of mediators like self-reported isolation and loneliness, Jiang and colleagues found that 1.5% of the total association between hearing aid use and all-cause dementia was mediated by improving social isolation, while 2.3% and 7.1% were mediated by reducing loneliness and depressed moods, respectively.

The researchers highlighted several potential causes behind the increased risk for dementia, which “include the reallocation of cognitive resources to auditory perceptual processing, cognitive deterioration due to long-term deprivation of auditory input, a common neurodegenerative process in the aging brain that drives both cognitive decline and hearing loss, and social isolation caused by both hearing and cognitive loss.”

“However, whether hearing aid use reduces the risk of dementia via reduction of the adverse effects of hearing loss on loneliness, social isolation, and depression is unclear,” they added.

Ultimately, the findings underlined the importance of implementing measures directed at hearing loss to reduce cognitive decline, Jiang and colleagues wrote.

“Public health strategies are necessary to raise awareness of hearing loss and the potential harm of untreated hearing impairment, increase accessibility to hearing aids by reducing cost, encouraging screening, and delivering potential interventions such as fitting hearing aids,” they wrote.

References:

• Jiang F, et al. Lancet Public Health. 2023;doi:10.1016/S2468-2667(23)00048-8
• The Lancet Public Health editors. Lancet Public Health. 2023;doi:10.1016/S2468-2667(22)00314-0.