Treating Hearing Loss Could 'Delay a Dementia Diagnosis'

People at risk of cognitive decline could cut their risk in half by getting hearing aids. That's according to a new study that has experts questioning whether governments should prioritize hearing health as a means to reducing dementia risk, per CNN. Previous research has shown hearing loss is a risk factor for dementia. Researchers set out to determine whether a simple intervention—hearing aids—could reduce that risk. They looked at nearly 1,000 people from two populations: healthy community volunteers and older adults who had lower cognition scores and more risk factors for cognitive decline. All participants were randomly assigned to receive counselling in chronic disease prevention or treatment from an audiologist, which included hearing aids.

After three years, the participants were given a comprehensive neurocognitive test. According to the study published Tuesday in the Lancet, "the hearing intervention did not reduce 3-year cognitive decline in the primary analysis of the total cohort." But researchers did see a difference within the group at higher risk. According to the Independent, "three-year cognitive change was 48% lower" among older adults given hearing aids, compared with those who weren't. As study author Dr. Frank Lin of Johns Hopkins University explains, "these results provide compelling evidence that treating hearing loss is a powerful tool to protect cognitive function in later life, and possibly, over the long term, delay a dementia diagnosis."

There are several links between hearing health and cognitive function. As cochlear function declines with age, the brain has to work harder to understand sounds. Hearing loss may also cause parts of the brain to shrink and discourage people from participating in social activities, which are shown to boost cognitive health. "But any cognitive benefits of treating age-related hearing loss are likely to vary depending on an individuals' risk of cognitive decline," Lin notes. Dr. Charles Marshall of Queen Mary University, who was not involved in the study, notes the results "don't yet tell us whether hearing aids are actually preventing dementia or just improving people's ability to perform cognitive testing," per the Independent. (Hearing aids are now available over the counter.)