insights

Hearing loss is one of the most common conditions affecting adults as they age. In the United States, nearly one in three people between the ages of 65 and 74 has difficulty hearing, and the prevalence increases for those over the age of 75.¹ The World Health Organization estimates that approximately 20% of the global population (1.5 billion people) lives with hearing loss.² As the pace of population aging continues to accelerate,^3,4 more than 2.5 billion people worldwide could be living with hearing loss by 2050.⁵

Studies associate hearing loss with increased reports of depression, loneliness, and social isolation as well as an overall reduced quality of life.^6-8 Recent research also emphasizes the connection to cognitive health. A growing number of people are affected by cognitive decline and dementia,^9,10 and hearing loss has not only been associated with mild cognitive impairment,¹¹ it has also been identified as a modifiable risk factor in the development of Alzheimer’s disease and related dementias.^12-14 Talking with your patients about hearing protection and potential hearing loss is an important preventative component for healthy aging. With the recent increased availability and accessibility of hearing aids, discussing hearing assessments with patients, explaining the importance of optimal hearing, and presenting options for intervention may help to reduce the enormous burden of cognitive decline and dementia in older populations.

Hearing Aids as Cognitive Health Aids

A 2021 meta-analysis of 14 cohort studies (n=726,900 adults) found that hearing loss was independently associated with a 59% increased risk of dementia (HR=1.59; 95% CI: 1.37-1.86) and significantly linked to a 124% higher risk of Alzheimer’s disease (HR=2.24; 95% CI: 1.32-3.79).¹³ A 2022 systematic review and analysis of 34 studies (n=48,017) found that individuals with peripheral hearing loss had a 106% increased risk of mild cognitive impairment compared to those without.¹¹ And based on 2019 data, a US report indicated that among the most common modifiable risk factors for Alzheimer’s disease and other dementias, such as high blood pressure (49.9% risk factor prevalence), reduced aerobic physical activity (49.7%), obesity (35.3%), diabetes (18.6%), depression (18.0%), cigarette smoking (14.9%), and binge drinking (10.3%), hearing loss had a 10.5% modifiable risk factor prevalence.¹⁴

These modifiable risk factors are huge opportunities for health promotion. Even more encouraging, recent studies have reported that the use of hearing aids reduces dementia risk¹⁵ and helps to mitigate hearing loss–related cognitive decline.¹⁶ In a 2022 cohort study, hearing aid users were less likely to develop mild cognitive impairment compared to hearing-impaired individuals who did not use a hearing aid (HR=0.47; 95% CI: 0.29-0.74).¹⁶ In a 2019 retrospective cohort study (n=114,862 adults aged >65 with a hearing loss diagnosis), those who obtained a hearing aid had an 18% decreased risk of dementia or Alzheimer’s disease diagnosis and an 11% decreased risk for anxiety and depression.¹⁵ Further, the risk of fall-related injuries dropped by 13%. In this study, researchers also reported that approximately 11.3% of women and 13.3% of men used hearing aids, as well as approximately 13.6% of white participants, 9.8% of Black participants, and 6.5% of Hispanic participants.¹⁵

In addition to disease risk reduction, hearing aid use continues to be studied for intervention benefits. For older adults with dementia, hearing loss treatments that include hearing aids have shown promise in improving symptoms related to dementia as well as communication difficulties.¹⁷ Studies also continue to clarify the mechanisms at work in the hearing loss/cognitive decline relationship¹⁸ and to better understand if cognition may be negatively impacted even during subclinical hearing loss.¹⁹

HEARING AID ACCESSIBILITY: OVER-THE-COUNTER

Even with the suggested benefits of hearing aids, only an estimated 12% of adults in the US diagnosed with hearing loss actually obtain hearing aids.¹⁵ Availability and financial barriers may have prevented many from pursuing this line of treatment. Until recently, hearing aids were only available by prescription and were often expensive. However, recent federal directives published in 2022 have mandated that hearing aids be available for purchase over-the-counter, without a prescription, exam, or audiologist fitting.²⁰ This effort to increase accessibility may also substantially reduce the financial burden. Prescription hearing aid prices have ranged considerably from $1,000 up to $3,500 per device. With over-the-counter accessibility, hearing aid costs could be lowered by as much as $3,000 per pair.²⁰

Protecting Patients From Hearing Loss

Many older adults who report hearing loss experience a combination of noise-induced hearing loss and age-related hearing loss. Protection from excessively loud and sustained noises can help reduce damage to the sensory hair cells in the ear. In addition, a healthy lifestyle may offer protection, as high blood pressure or diabetes can also contribute to hearing loss.¹ For younger patients who have a family history of cognitive decline and/or hearing loss, emerging research suggests that nutrition may play a critical protective role.²¹ In one study of women, adhering to a healthier dietary pattern (specifically, the Mediterranean diet or the Dietary Approaches to Stop Hypertension (DASH) diet) reduced the chance of self-reported hearing loss by approximately 30%.²² The mechanisms by which nutrition may impact hearing are likely many and varied, including insulin resistance, adiponectin decline, dyslipidemia, and more.²³

Conclusion

For the many patients with hearing loss who have not yet taken the important step of hearing loss treatment, clear explanation from a clinician of the benefits of this treatment may make all the difference. The patient-practitioner relationship is a cornerstone of functional medicine, and loss of hearing can compromise that relationship, as well as a patient’s other personal relationships, which makes addressing their hearing loss all the more important. Attending to each patient’s sensory needs has the potential to benefit all of our patients.

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References

1. National Institute on Deafness and Other Communication Disorders. Age-related hearing loss. National Institutes of Health. Updated March 16, 2022. Accessed November 4, 2022. https://www.nidcd.nih.gov/health/age-related-hearing-loss
2. World Health Organization. Deafness and hearing loss. Accessed November 4, 2022. https://www.who.int/health-topics/hearing-loss#tab=tab_2
3. World Health Organization. Ageing and health. Published October 1, 2022. Accessed November 4, 2022. https://www.who.int/news-room/fact-sheets/detail/ageing-and-health
4. The Administration for Community Living, Administration on Aging. 2020 profile of older Americans. US Department of Health and Human Services. Published May 2021. Accessed November 4, 2022. https://acl.gov/sites/default/files/aging%20and%20Disability%20In%20America/2020Profileolderamericans.final_.pdf
5. GBD 2019 Hearing Loss Collaborators. Hearing loss prevalence and years lived with disability, 1990-2019: findings from the Global Burden of Disease Study 2019. Lancet. 2021;397(10278):996-1009. doi:1016/S0140-6736(21)00516-X
6. Dixon PR, Feeny D, Tomlinson G, Cushing S, Chen JM, Krahn MD. Health-related quality of life changes associated with hearing loss. JAMA Otolaryngol Head Neck Surg. 2020;146(7):630-638. doi:1001/jamaoto.2020.0674
7. Lawrence BJ, Jayakody DMP, Bennett RJ, Eikelboom RH, Gasson N, Friedland PL. Hearing loss and depression in older adults: a systematic review and meta-analysis. Gerontologist. 2020;60(3):e137-e154. doi:1093/geront/gnz009
8. Shukla A, Harper M, Pedersen E, et al. Hearing loss, loneliness, and social isolation: a systematic review. Otolaryngol Head Neck Surg. 2020;162(5):622-633. doi:1177/0194599820910377
9. World Health Organization. Dementia. Published September 20, 2022. Accessed October 25, 2022. https://www.who.int/news-room/fact-sheets/detail/dementia
10.  Rajan KB, Weuve J, Barnes LL, McAninch EA, Wilson RS, Evans DA. Population estimate of people with clinical Alzheimer’s disease and mild cognitive impairment in the United States (2020-2060). Alzheimers Dement. 2021;17(12):1966-1975. doi:1002/alz.12362
11.  Lau K, Dimitriadis PA, Mitchell C, Martyn-St-James M, Hind D, Ray J. Age-related hearing loss and mild cognitive impairment: a meta-analysis and systematic review of population-based studies. J Laryngol Otol. 2022;136(2):103-118. doi:1017/S0022215121004114
12.  Office of the Assistant Secretary for Planning and Evaluation. National plan to address Alzheimer’s disease: 2021 update. US Department of Health and Human Services. Published December 27, 2021. Accessed November 7, 2022. https://aspe.hhs.gov/reports/national-plan-2021-update
13.  Liang Z, Li A, Xu Y, Qian X, Gao X. Hearing loss and dementia: a meta-analysis of prospective cohort studies. Front Aging Neurosci. 2021;13:695117. doi:3389/fnagi.2021.695117
14.  Omura JD, McGuire LC, Patel R, et al. Modifiable risk factors for Alzheimer disease and related dementias among adults aged ≥45 years – United States, 2019. MMWR Morb Mortal Wkly Rep. 2022;71(20):680-685. doi:15585/mmwr.mm7120a2
15.  Mahmoudi E, Basu T, Langa K, et al. Can hearing aids delay time to diagnosis of dementia, depression, or falls in older adults? J Am Geriatr Soc. 2019;67(11):2362-2369. doi:1111/jgs.16109
16.  Bucholc M, Bauermeister S, Kaur D, McClean PL, Todd S. The impact of hearing impairment and hearing aid use on progression to mild cognitive impairment in cognitively healthy adults: an observational cohort study. Alzheimers Dement (N Y). 2022;8(1):e12248. doi:1002/trc2.12248
17.  Mamo SK, Reed NS, Price C, et al. Hearing loss treatment in older adults with cognitive impairment: a systematic review. J Speech Lang Hear Res. 2018;61(10):2589-2603. doi:1044/2018_JSLHR-H-18-0077
18.  Zheng M, Yan J, Hao W, et al. Worsening hearing was associated with higher β-amyloid and tau burden in age-related hearing loss. Sci Rep. 2022;12(1):10493. doi:1038/s41598-022-14466-6
19.  Babajanian EE, Gurgel RK. Cognitive and behavioral effects of hearing loss. Curr Opin Otolaryngol Head Neck Surg. 2022;30(5):339-343. doi:1097/MOO.0000000000000825
20.  Fact sheet: cheaper hearing aids now in stores thanks to Biden-Harris Administration competition agenda. White House. Published October 17, 2022. Accessed November 7, 2022. https://www.whitehouse.gov/briefing-room/statements-releases/2022/10/17/fact-sheet-cheaper-hearing-aids-now-in-stores-thanks-to-biden-harris-administration-competition-agenda/
21.  Rodrigo L, Campos-Asensio C, Rodríguez MÁ, Crespo I, Olmedillas H. Role of nutrition in the development and prevention of age-related hearing loss: a scoping review. J Formos Med Assoc. 2021;120(1 Pt 1):107-120. doi:1016/j.jfma.2020.05.011
22.  Curhan SG, Wang M, Eavey RD, Stampfer MJ, Curhan GC. Adherence to healthful dietary patterns is associated with lower risk of hearing loss in women. J Nutr. 2018;148(6):944-951. doi:1093/jn/nxy058
23.  Tang TH, Hwang JH, Yang TH, Hsu CJ, Wu CC, Liu TC. Can nutritional intervention for obesity and comorbidities slow down age-related hearing impairment? Nutrients. 2019;11(7):E1668. doi:3390/nu11071668