A new study published in JAMA Neurology has reported that among 353 older adults with mild cognitive impairment and coexisting hearing loss, a hearing aid intervention did not significantly reduce the incidence of dementia-level impairment at 24 months. Hearing loss has been identified as a key risk factor for dementia and there is observational evidence that hearing interventions might result in delayed dementia. The trial, which was conducted across six centres in Shanghai, China, screened 21,908 adults before randomizing eligible participants to either the hearing aid intervention (n=353) or the hearing care education control (n=350). Those in the hearing intervention arm received free binaural behind-the-ear hearing aids that were fitted by a certified audiologist, along with education on the proper use of hearing aids. People in the control arm received group-based, structured hearing care education that focused on five core topics: 1) the nature of hearing loss; 2) practical hearing care; 3) chronic disease management; 4) healthy lifestyle modifications; and 5) cognitive decline prevention strategies.
After a period of 24 months of follow-up, the researchers found that the hearing aid intervention did not result in a significant difference in the primary outcome – conversion rate from mild cognitive impairment to dementia level impairment. The latter was assessed via the Clinical Dementia Rating clinical interview - a validated instrument for staging global cognitive-functional severity. A pre-specified secondary endpoint, rate of cognitive improvement, was 15.34% in the intervention group compared to 2.36% in the control group. However, the authors advise caution in interpretation of this outcome as improved hearing may have enhanced understanding of verbal test instructions and thus influenced cognitive assessment results.
More information on this study is available here: https://jamanetwork.com/journals/jamaneurology/fullarticle/2854483
