A recent study has found that individuals who are at a higher risk of cognitive decline can significantly reduce their risk by using hearing aids.
Cognitive decline refers to a range of decreased cognitive abilities, from mild impairment to dementia, which is a global concern, according to the US Centers for Disease Control and Prevention.
Dr. Frank Lin, a professor at Johns Hopkins University School of Medicine and the Bloomberg School of Public Health, stated that as people live longer, the number of individuals with dementia is increasing.
Previous research over the past decade has identified hearing loss as one of the major risk factors for developing dementia.
However, it remained uncertain whether the use of hearing aids could mitigate this risk, explained Dr. Lin. The study published in the Lancet was the first randomized control study to address this question.
The study involved over 3,000 participants from two groups: healthy community volunteers and older adults from the Atherosclerosis Risk in Communities (ARIC) study, which examines cardiovascular health.
The participants were randomly assigned to either a control group that received counseling for chronic disease prevention or an intervention group that received treatment from an audiologist and were provided with hearing aids.
The researchers followed up with both groups every six months for a duration of three years, and at the end, they conducted a comprehensive neurocognitive test to evaluate their cognitive function.
The study indicated that hearing aids did not appear to reduce cognitive decline in the entire group. However, when focusing on the older group at higher risk, a significant reduction in cognitive decline was observed.
Dr. Thomas Holland, a physician-scientist at the Rush Institute for Healthy Aging who was not involved in the study, described the 48% reduction in cognitive decline among the higher-risk individuals as impressive.
The smaller change observed in the total population could be attributed to the fact that the healthy participants, who were at lower risk, did not experience significant cognitive decline to begin with, suggesting that hearing aids may have a limited impact in such cases.
Dr. Lin added that the population at higher risk demonstrated rates of cognitive decline nearly three times higher than their counterparts. These results raise the question of whether hearing health should be prioritized by governments and individuals to reduce the risk of dementia.
Several mechanisms may explain the link between hearing loss and dementia.
Firstly, as people age, their hearing naturally declines, and this could lead to the inner ear sending distorted signals to the brain, requiring increased effort and brain resources to interpret sounds.
Secondly, hearing loss may have structural effects on the brain, causing certain areas to shrink or atrophy more rapidly, which is detrimental to brain health.
Lastly, individuals with hearing loss may be less likely to engage in social activities, which are known to be important for maintaining cognitive health.
Dr. Lin emphasized the importance of getting one’s hearing checked, regardless of the severity of hearing loss.
Dr. Benjamin Tan, Dean’s Fellow at the Yong Loo Lin School of Medicine at the National University of Singapore, who was not involved in the study, recommended using hearing aids, even for mild hearing loss, as a simple and risk-free method to preserve cognitive function.
Unfortunately, not everyone has access to regular consultations with ear, nose, and throat doctors or audiologists. In such cases, over-the-counter hearing aids, which can be obtained without a prescription and at a lower cost, may be a viable option, according to Dr. Tan.
The study also underscored the significance of maintaining physical health to prevent cognitive decline. Regular visits to a primary care provider, engaging in physical activity, consuming a diet rich in leafy greens, berries, and omega-type fatty acids, ensuring sufficient sleep, and engaging in cognitive stimulation through learning new things are essential for maintaining brain health.
These elements are particularly important for individuals with hearing loss, atherosclerosis, high blood pressure, heart disease, or neurovascular disease, as stated by Dr. Holland.
Taking proactive measures to prevent or build resilience against cognitive decline and dementia is crucial. Early intervention is key to either preventing the disease process or enhancing resilience when facing such conditions, concluded Dr. Holland.