The Longitudinal Association of Subclinical Hearing Loss With Cognition in the Health, Aging and Body Composition Study

Design and Methods of the Early Age-Related Hearing Loss Investigation Randomized Controlled Trial

OBJECTIVE

Hearing loss has been identified as a major modifiable risk factor for cognitive decline. The Early Age-Related Hearing Loss Investigation (EARHLI) study will assess the mechanisms linking early age-related hearing loss (ARHL) and cognitive impairment.

STUDY DESIGN

Randomized, controlled, single-site, early phase II, superiority trial.

SETTING

Tertiary academic medical center.

PARTICIPANTS

One hundred fifty participants aged 55 to 75 years with early ARHL (severity defined as borderline to moderate) and amnestic mild cognitive impairment will be included.

INTERVENTIONS

Participants will be randomized 1:1 to a best practice hearing intervention or a health education control.

MAIN OUTCOME MEASURES

The primary study outcome is cognition measured by the Alzheimer Disease Cooperative Study-Preclinical Alzheimer Cognitive Composite. Secondary outcomes include additional measures of cognition, social engagement, and brain organization/connectivity.

RESULTS

Trial enrollment will begin in early 2024.

CONCLUSIONS

After its completion in 2028, the EARHLI trial should offer evidence on the effect of hearing treatment versus a health education control on cognitive performance, social engagement, and brain organization/connectivity in 55- to 75-year-old community-dwelling adults with early ARHL and amnestic mild cognitive impairment.

Hearing help-seeking, hearing device uptake and hearing health outcomes in individuals with subclinical hearing loss: a systematic review

OBJECTIVE

This systematic review aims to examine the current literature on help-seeking, hearing device uptake, and hearing health outcomes in individuals with subclinical hearing loss.

DESIGN

Systematic review.

STUDY SAMPLE

Searches of three databases (CINAHL, MEDLINE (PubMed), and Scopus) yielded nine studies meeting the inclusion criteria. The quality of the included studies was determined using the National Institute of Health quality assessment tool. The studies' level of evidence was determined according to the Centre for Evidence-Based Medicine.

RESULTS

All included studies involved adult participants. Three studies examined help-seeking. Self-reported difficulty, poor speech-in-noise performance, and emotional responses to the hearing difficulty were identified as factors influencing help-seeking. Six studies examined the use of hearing devices as an intervention, including hearing aids (n = 4), hearables (n = 1), and FM systems (n = 1). Using hearing devices improved self-perceived hearing difficulty, speech-in-noise understanding, and motivation to address hearing difficulties. No studies focused on hearing device uptake. The quality assessment indicated limited methodological rigour across the studies, with varying levels of evidence.

CONCLUSIONS

Current evidence supports the use of hearing devices as an intervention for individuals with subclinical hearing loss. However, more research is essential, particularly focusing on help-seeking, diagnosis, treatment, and long-term outcomes using well-controlled study designs.

Moderating Role of Neighborhood Environment in the Associations Between Hearing Loss and Cognitive Challenges Among Older Adults: Evidence From US National Study

This study examined the associations between hearing loss and cognitive challenges among community-dwelling older adults and whether neighborhood characteristics (physical disorder and low social cohesion) moderated the associations. Cross-sectional national data from Round 11 of the National Health and Aging Trends Study were adopted (N = 2,515). Multinomial logistic regressions were used to examine associations among variables and interactive analyses were conducted to examine moderating effects. Results indicated significant relationships between the experience of hearing loss and possible dementia and between severe or profound hearing loss and probable dementia. Interactive models suggested that residing in neighborhoods with physical disorder and low social cohesion were negatively associated with possible dementia among older adults with moderate and severe or profound hearing loss, respectively, compared to those without hearing loss. Findings underscore the necessity of environmental and social interventions to enhance cognitive health among older adults with varying degrees of hearing challenges.

Cochlear dysfunction as an early biomarker of cognitive decline in normal hearing and mild hearing loss

INTRODUCTION

Age-related hearing loss is an important risk factor for cognitive decline. However, audiogram thresholds are not good estimators of dementia risk in subjects with normal hearing or mild hearing loss. Here we propose to use distortion product otoacoustic emissions (DPOAEs) as an objective and sensitive tool to estimate the risk of cognitive decline in older adults with normal hearing or mild hearing loss.

METHODS

We assessed neuropsychological, brain magnetic resonance imaging, and auditory analyses on 94 subjects > 64 years of age.

RESULTS

We found that cochlear dysfunction, measured by DPOAEs-and not by conventional audiometry-was associated with Clinical Dementia Rating Sum of Boxes (CDR-SoB) classification and brain atrophy in the group with mild hearing loss (25 to 40 dB) and normal hearing (<25 dB).

DISCUSSION

Our findings suggest that DPOAEs may be a non-invasive tool for detecting neurodegeneration and cognitive decline in the older adults, potentially allowing for early intervention.

Prevalence of Subclinical Hearing Loss in the United States

OBJECTIVE

Current definitions of hearing loss (HL) may be insufficiently strict, as subclinical hearing loss (SCHL; >0 and ≤25 dB hearing level) has been associated with deleterious age-related conditions. SCHL prevalence and mean age of HL onset in the United States has not been characterized.

STUDY DESIGN

A cross-sectional epidemiologic prevalence study.

SETTING

US Community.

METHODS

We analyzed cross-sectional audiometric data in the US National Health and Nutrition Examination Survey (2005-2012, 2015-2018, n = 15,649). Results were scaled to the current population using weighting.

RESULTS

79.6% of participants (227.32 million Americans) had SCHL. The mean age of HL onset at thresholds of 25, 20, and 15 dB was 74, 66, and 55 years, respectively, for the 4-frequency pure-tone average, and 48, 44, and 35 years for the high-frequency pure-tone average.

CONCLUSION

We present SCHL prevalence and define HL onset by various sensitive definitions. These results inform ongoing public health efforts to increase hearing aid utilization, particularly given the arrival of over-the-counter hearing aids.

Association Between Hearing Loss and Multiple Negative Emotional States in the US Hispanic Population

OBJECTIVE

Hearing loss (HL) has been linked to commonly studied detrimental mood states, such as loneliness and depression. However, its relationship with other negative emotions remained largely unstudied. We explore the association between HL and anxiety, anger, hostility, poor self-esteem, and pessimism in a national cohort of US Hispanic adults.

STUDY DESIGN

Cross-sectional study.

SETTING

Multicentered US national epidemiologic study (Hispanic Community Health Study).

METHODS

Subjects were ages 18 to 75 with completed audiometric and emotional survey data. Multivariable regressions controlling for age, gender, and education were conducted to analyze the association between HL, measured by 4-frequency pure-tone average (PTA), and emotional states. States included anxiety (Spielberger Trait Anxiety Scale-10), anger (Spielberger Trait Anger Scale), hostility (Cook Medley Cynicism Scale-13), poor self-esteem (Self-Esteem Scale-10), and pessimism (Revised Life Orientation Test).

RESULTS

A total of 4120 to 4341 participants met inclusion criteria, depending on the specific survey; the average age was 46.7 years (standard deviation [SD] = 13.7), and the average PTA was 13.8 dB (SD = 10.1). Controlling for age, gender, and education, HL was associated with all outcomes. Specifically, for every 10 dB worsening in HL, the anxiety score worsened by 0.41 (0.23-0.60), the anger score worsened by 0.40 (0.22-0.58), the hostility score worsened by 0.16 (0.04-0.27), the self-esteem score worsened by 0.25 (0.12-0.38), and the pessimism score worsened by 0.17 (0.04-0.30) (all p < .01).

CONCLUSION

HL is related to numerous negative mood states beyond loneliness and depression. This includes worse anxiety, anger, hostility, self-esteem, and pessimism. Future studies should investigate whether treating HL improves negative emotional states.

Probability Distributions for Associations Between Cognitive Screening and Pure-tone Thresholds in Older Adults

OBJECTIVES

Lower general cognitive function is frequently reported in older adults with elevated pure-tone thresholds. Here, we examined reason(s) for this association, including whether this relationship is dependent on the frequency range or extent of hearing loss and cognitive screening performance.

DESIGN

Linear regression was used to examine associations between better-ear pure-tone thresholds and Mini-Mental Status Exam (MMSE) performance in a cross-sectional sample of relatively healthy older adults (N = 508; 68% women, 60-89+ years; M age = 72). Quantile regression was also used to identify the ranges of 0.5 and 4.0 kHz thresholds and MMSE scores where these variables exhibited significant associations.

RESULTS

MMSE scores and pure-tone thresholds exhibited small but significant associations, particularly for better-ear 0.5 kHz thresholds. This hearing threshold and cognitive screening association was present among participants with better hearing, including the oldest older adults. There was limited evidence for mediating health condition effects on this association. An item analysis of the MMSE revealed that the MMSE and pure-tone threshold associations were largely due to the delayed recall item of the MMSE.

CONCLUSIONS

Together, the small effect results are consistent with the extant literature and suggest that there are multiple reasons for modest pure-tone threshold and cognitive screening performance associations.

Cognitive and behavioral effects of hearing loss

PURPOSE OF REVIEW

Hearing loss is one of the largest modifiable risk factors for developing dementia, accounting for up to 9% of the overall modifiable risk. The neuropsychologic and psychosocial impacts of hearing loss are becoming increasingly appreciated. The objective of this review is to explore the recent literature regarding the cognitive and behavioral effects of hearing loss and the role of hearing rehabilitation, particularly in older adults.

RECENT FINDINGS

Cognitive decline may begin while patients have subclinical hearing loss, earlier than previously thought. Hearing rehabilitation, either via hearing amplification, middle ear surgery, or cochlear implantation, likely plays a role in preventing or slowing the rate of cognitive decline in patients with hearing loss. Hearing loss can increase the likelihood of social isolation, loneliness and depression in older adults, but it is unclear at this time what effect hearing rehabilitation has on these domains.

SUMMARY

Hearing loss is one of the largest modifiable risk factors for cognitive decline, and hearing rehabilitation can play a significant role in preserving cognitive function. Understanding the cognitive and psychosocial impact of hearing loss can help facilitate the development of approaches for prevention and treatment.