Hearing loss and incident dementia

Adult-onset hearing loss and incident cognitive impairment and dementia - A systematic review and meta-analysis of cohort studies

BACKGROUND

We comprehensively summarized the cohort evidence to date on adult-onset hearing loss as risk factor for incident cognitive impairment and dementia, and examined the evidence for dose-response, risk for various dementia subtypes, and other moderators. Previous meta-analyses were less comprehensive.

METHODS

We included cohort studies with participants without dementia and with hearing assessments at baseline, minimum 2 years follow-up and incident cognitive outcomes. We used random-effect models and subgroup and meta-regression on moderator analyses.

RESULTS

We identified fifty studies (N=1,548,754). Hearing loss (yes/no) was associated with incident dementia risk (HR=1.35 [95% CI = 1.26 - 1.45), mild cognitive impairment (MCI HR=1.29 [95% CI = 1.11 - 1.50]), cognitive decline not specified as MCI or dementia (HR=1.29 [95% CI = 1.17 - 1.42]), and Alzheimer's disease dementia (ADD, HR=1.56 [95% CI = 1.30 - 1.87]), but not with vascular dementia (HR, 1.30 [95% CI = 0.83 - 2.05]). Each 10-decibel worsening of hearing was associated with a 16% increase in dementia risk (95% CI = 1.07 - 1.27). The effect of hearing loss did not vary across potential moderators.

CONCLUSIONS

Cohort studies consistently support that adult-onset hearing loss increases the risk of incident cognitive decline, dementia, MCI, and ADD.

Comparison of postural control and space perception outcomes between robotic and conventional cochlear implantation in adults

PURPOSE

The aim of the study is to capture the difference between the groups in direct relation to the type of electrode array insertion during cochlear implantation (CI). The robotic insertion is expected to be a more gently option. As recent studies have shown, there is a difference in perception of visual vertical (SVV) and postural control related to the CI. We assume that there can be differences in postural control and space perception outcomes depending on the type of the surgical method.

METHODS

In total, 37 (24 females, mean age ± SD was 42.9 ± 13.0) candidates for CI underwent an assessment. In 14 cases, the insertion of the electrode array was performed by a robotic system (RobOtol, Colin, France) and 23 were performed conventionally. In all of these patients, we performed the same examination before the surgery, the first day, and 3 weeks after the surgery. The protocol consists of static posturography and perception of visual vertical.

RESULTS

The both groups, RobOtol and conventional, responded to the procedure similarly despite the dissimilar electrode insertion. There was no difference between two groups in the dynamic of perception SVV and postural parameters. Patients in both groups were statistically significantly affected by the surgical procedure, SVV deviation appeared in the opposite direction from the implanted ear: 0.90° ± 1.25; - 1.67° ± 3.05 and - 0.19° ± 1.78 PRE and POST surgery (p < 0.001). And this deviation was spontaneously adjusted in FOLLOW-UP after 3 weeks (p < 0.01) in the both groups. We did not find a significant difference in postural parameters between the RobOtol and conventional group, even over time.

CONCLUSION

Although the robotic system RobOtol allows a substantial reduction in the speed of insertion of the electrode array into the inner ear, our data did not demonstrate a postoperative effect on vestibular functions (SVV and posturography), which have the same character and dynamics as in the group with standard manual insertion.

REGISTRATION NUMBER

The project is registered on clinicaltrials.gov (registration number: NCT05547113).

Longitudinal urinary neopterin is associated with hearing threshold change over time in independent older adults

Low-grade chronic inflammation is associated with many age-related conditions. Non-invasive methods to monitor low-grade chronic inflammation may improve the management of older people at risk of poorer outcomes. This longitudinal cohort study has determined baseline inflammation using neopterin volatility in monthly urine samples of 45 independent older adults (aged 65-75 years). Measurement of neopterin, an inflammatory metabolite, enabled stratification of individuals into risk categories based on how often in a 12-month period their neopterin level was raised. Hearing was measured (pure-tone audiometry) at baseline, 1 year and 3 years of the study. Results show that those in the highest risk category (neopterin raised greater than 50% of the time) saw greater deterioration, particularly in high-frequency, hearing. A one-way Welch's ANOVA showed a significant difference between the risk categories for change in high-frequency hearing (W (3, 19.6) = 9.164, p = 0.0005). Despite the study size and duration individuals in the highest risk category were more than twice as likely to have an additional age-related morbidity than those in the lowest risk category. We conclude that volatility of neopterin in urine may enable stratification of those at greatest risk of progression of hearing loss.

'The burden is very much on yourself': A qualitative study to understand the illness and treatment burden of hearing loss across the life course

INTRODUCTION

Hearing loss is a chronic health condition that rises sharply with age. The way people respond to and cope with health conditions is influenced by their capacity to perform illness and treatment-related work. The aim was to explore the cumulative burdens of living with hearing loss and the resources mobilised to ease the burdens.

METHODS

A qualitative design was used with semi-structured interviews (online or in-person) with participants recruited through audiology services and nonclinical services, such as lip-reading classes. Forty-six participants with hearing loss aged between 16 and 96 years were interviewed. An abductive approach, informed by May et al.'s burden of treatment theory, was used to analyse the data.

RESULTS

The illness burden involved participants working to make sense of their hearing loss, engaging in emotional work in response to changes in sound, social interactions and identity and coping with the daily frustrations required to communicate with others. Abandonment and uncertainty characterised the treatment burden; participants engaged in emotional work to adjust to hearing technology and deal with the uncertainty of how their hearing might progress. To ameliorate the burdens, participants drew on internal resources (psychological, health literacy, cognitive) and external resources (social support, financial, information, technology).

CONCLUSIONS

The workload of hearing loss appears largely devolved to the patient and is not always visible. Our work indicates the need to widen approaches in audiological care through the implementation of lifeworld-led care, family-centred care and peer support to build support for those with hearing loss.

PATIENT OR PUBLIC CONTRIBUTION

We developed the project in consultation with members of the public who have lived experience of hearing loss recruited through Aston University and volunteer links to audiology services. We also consulted people more likely to be affected by hearing loss adults including adults with learning disabilities, older adults in residential care and people from South Asia (Bangladeshi, Indian and Pakistani communities). These individuals commented on the study aims, interview schedule and participant recruitment practices. One of our co-authors (expert by experience) contributed to the development and interpretation of themes and preparation of the final manuscript.

Factors correlated with hearing aids adherence in older adults: a prospective controlled study

OBJECTIVE

To investigate which factors influence the adherence to hearing aid (HA) use in elderly patients with moderate-to-severe hearing loss.

METHODS

This observational, prospective, single-centre study enrolled patients with moderate-to-severe hearing loss. They were evaluated before and 1 year after having either one or two HAs fitted.

RESULTS

A total of 86 patients were enrolled in the study and of these 69.8% (60 of 86; USER group) continued to use their HA at 1 year after fitting; six patients had not continued their use (NON-USERS). The USER group was younger than the NON-USER group, but the difference was not significant. The USER group had a significantly better unaided auditory threshold at baseline than the NON-USER group. HA use resulted in improvements in speech audiometry and auditory threshold. There was also a maintenance of cognitive function in the USER group.

CONCLUSION

Use of HA for 1 year resulted in improved auditory performance and an absence of a deterioration of cognitive function.Trial registration: This research was retrospectively registered under no. NCT04333043 at ClinicalTrials.gov (http://www.clinicaltrials.gov/) on the 26 March 2020. This research has been registered with the Ethics Committee of the Area Vasta Emilia Nord under number 104, date of approval 17/07/2017.

Development and validation of the screening tool for age-related hearing loss in the community based on the information platform

INTRODUCTION

Currently, age-related hearing loss has become prevalent, awareness and screening rates remain dismally low. Duing to several barriers, as time, personnel training and equipment costs, available hearing screening tools do not adequately meet the need for large-scale hearing detection in community-dwelling older adults. Therefore, an accurate, convenient, and inexpensive hearing screening tool is needed to detect hearing loss, intervene early and reduce the negative consequences and burden of untreated hearing loss on individuals, families and society.

OBJECTIVES

The study harnessed "medical big data" and "intelligent medical management" to develop a multi-dimensional screening tool of age-related hearing loss based on WeChat platform.

METHODS

The assessment of risk factors was carried out by cross-sectional survey, logistic regression model and receiver operating characteristic (ROC) curve analysis. Combining risk factor assessment, Hearing handicap inventory for the elderly screening version and analog audiometry, the screening software was been developed by JavaScript language and been evaluated and verified.

RESULTS

A total of 401 older adults were included in the cross-sectional study. Logistic regression model (univariate, multivariate) and reference to literature mention rate of risk factors, 18 variables (male, overweight/obesity, living alone, widowed/divorced, history of noise, family history of deafness, non-light diet, no exercising habit, smoking, drinking, headset wearer habit, hypertension, diabetes, hyperlipidemia, cardiovascular and cerebrovascular diseases, hyperuricemia, hypothyroidism, history of ototoxic drug use) were defined as risk factors. The area under the ROC curve (AUC) of the cumulative score of risk factors for early prediction of age-related hearing loss was 0.777 [95% CI (0.721, 0.833)]. The cumulative score threshold of risk factors was defined as 4, to classify the older adults into low-risk (< 4) and high-risk (≥ 4) hearing loss groups. The sensitivity, specificity, positive predictive value, and negative predictive value of the screen tool were 100%, 65.5%, 71.8%, and 100.0%, respectively. The Kappa index was 0.6.

CONCLUSIONS

The screening software enabled the closed loop management of real-time data transmission, early warning, management, whole process supervision of the hearing loss and improve self-health belief in it. The software has huge prospects for application as a screening approach for age-related hearing loss.

Impact of Insertion Speed, Depth, and Robotic Assistance on Cochlear Implant Insertion Forces and Intracochlear Pressure: A Scoping Review

Cochlear implants are crucial for addressing severe-to-profound hearing loss, with the success of the procedure requiring careful electrode placement. This scoping review synthesizes the findings from 125 studies examining the factors influencing insertion forces (IFs) and intracochlear pressure (IP), which are crucial for optimizing implantation techniques and enhancing patient outcomes. The review highlights the impact of variables, including insertion depth, speed, and the use of robotic assistance on IFs and IP. Results indicate that higher insertion speeds generally increase IFs and IP in artificial models, a pattern not consistently observed in cadaveric studies due to variations in methodology and sample size. The study also explores the observed minimal impact of robotic assistance on reducing IFs compared to manual methods. Importantly, this review underscores the need for a standardized approach in cochlear implant research to address inconsistencies and improve clinical practices aimed at preserving hearing during implantation.

The lived experience of hearing loss - an individualised responsibility

OBJECTIVE

This study aimed to provide a conceptual model to understand what typifies the lived experience of hearing loss.

DESIGN

A grounded theory informed study of adults with hearing loss (n = 46) who participated in individual interviews. The data were analysed in line with the constant comparative approach of grounded theory. A substantial patient and public engagement (PPIE) strategy underpinned decisions and processes throughout.

STUDY SAMPLE

Adults were recruited from age bands (16-29; 30-49;50-79 and 80 upwards) to provide different lived experience. We recruited individuals from across the UK including urban, sub-urban and rural communities and included a typical constituency of each location including black and minority ethnic participants. Our PPIE groups included adults often marginalised in research including South Asian community groups, adults in residential care and those with additional disabilities.

RESULTS

We identified the consistent features of the lived experience with hearing loss, as the individualised responsibility that hearing loss confers. These are an individual auditory lifeworld; social comparison and social support; individual and patient-centred care and individual agency and capability.

CONCLUSIONS

This work provides new insights for those practising audiology and highlights the importance of building social support systems through implementation of family and peer support approaches.

Detecting language network alterations in mild cognitive impairment using task-based fMRI and resting-state fMRI: A comparative study

OBJECTIVE

The objective of this study was to investigate the functional changes associated with mild cognitive impairment (MCI) using independent component analysis (ICA) with the word generation task functional magnetic resonance imaging (fMRI) and resting-state fMRI.

METHODS

In this study 17 patients with MCI and age and education-matched 17 healthy individuals as control group are investigated. All participants underwent resting-state fMRI and task-based fMRI while performing the word generation task. ICA was used to identify the appropriate independent components (ICs) and their associated networks. The Dice Coefficient method was used to determine the relevance of the ICs to the networks of interest.

RESULTS

IC-14 was found relevant to language network in both resting-state and task-based fMRI, IC-4 to visual, and IC-28 to dorsal attention network (DAN) in word generation task-based fMRI by Sorento-Dice Coefficient. ICA showed increased activation in language network, which had a larger voxel size in resting-state functional MRI than word generation task-based fMRI in the bilateral lingual gyrus. Right temporo-occipital fusiform cortex, right hippocampus, and right thalamus were also activated in the task-based fMRI. Decreased activation was found in DAN and visual network MCI patients in word generation task-based fMRI.

CONCLUSION

Task-based fMRI and ICA are more sophisticated and reliable tools in evaluation cognitive impairments in language processing. Our findings support the neural mechanisms of the cognitive impairments in MCI.

Depression and Health-Related Quality of Life Among Older Adults With Hearing Loss in the ACHIEVE Study

Hearing loss is associated with cognitive/physical health; less is known about mental health. We investigated associations between hearing loss severity, depression, and health-related quality of life among older adults with unaided hearing loss. Data (N = 948) were from the Aging and Cognitive Health Evaluation in Elders Study. Hearing was measured by pure-tone average (PTA), Quick Speech-in-Noise (QuickSIN) test, and the Hearing Handicap Inventory for the Elderly (HHIE-S). Outcomes were validated measures of depression and health-related quality of life. Associations were assessed by negative binomial regression. More severe hearing loss was associated with worse physical health-related quality of life (ratio: .98, 95% CI: .96, 1.00). Better QuickSIN was associated with higher mental health-related quality of life (1.01 [1.00, 1.02]). Worse HHIE-S was associated with depression (1.24 [1.16, 1.33]) and worse mental (.97 [.96, .98]) and physical (.95 [ .93, .96]) health-related quality of life. Further work will test effects of hearing intervention on mental health.

Associations between dietary indices and hearing status among middle-older aged adults - results from the Baltimore Longitudinal Study of Aging

BACKGROUND

Hearing loss, a public health issue in older populations, is closely related to functional decline.

OBJECTIVE

To investigate the longitudinal associations between 4 dietary indices and hearing status.

METHODS

Data from the Baltimore Longitudinal Study of Aging were used and included 882 participants ≥45 y of age. Dietary intake was assessed using a validated food frequency questionnaire, and 4 dietary scores (Mediterranean-Dietary Approaches to Stop Hypertension Intervention for Neurodegenerative Delay diet [MIND], Mediterranean style diet score [MDS], Alternative Healthy Eating Index [AHEI], and Healthy Eating Index [HEI]) were calculated as averages over time. Hearing status was examined using pure-tone audiometry, and pure-tone average (PTA) of hearing thresholds were calculated at speech-level (PTA(500, 1000, 2000, 4000 Hz)), low (PTA(500, 1000 Hz)), and high (PTA(4000, 8000 Hz)) frequencies, with lower thresholds indicating better hearing. Multivariable linear mixed-effect models were used to examine associations between dietary indices and hearing threshold change over time adjusted for confounders.

RESULTS

At baseline, the mean age of participants was 67 y and 55% were female. Over a median of 8 y of follow-up, MDS ≥7 was associated with 3.5 (95% CI: -6.5, -0.4) and 5.0 (95% CI: -9.1, -1.0) dB lower PTA(500, 1000, 2000, 4000 Hz) and PTA(4000, 8000 Hz), respectively, compared with MDS ≤3; the highest tertile of the AHEI was associated with 2.3 (95% CI: -4.6, -0.1) and 5.0 (95% CI: -8.0, -2.0) dB lower PTA(500, 1000, 2000, 4000 Hz) and PTA(4000, 8000 Hz); and each standard deviation increment in HEI was associated with 1.6 dB (95% CI: -2.7, -0.6), 1.1 dB (95% CI: -2.1, -0.1), and 2.1 dB (95% CI: -3.5, -0.6) lower PTA(500, 1000, 2000, 4000 Hz), PTA(500, 1000 Hz), and PTA(4000, 8000 Hz), respectively.

CONCLUSIONS

Adherence to healthy dietary patterns was associated with better hearing status, with stronger associations at high frequencies. Am J Clin Nutr 20xx;x:xx.

Hearing Loss and Dementia: Where to From Here?

Victorian era psychologists were the first to comment on associations between sensory and cognitive function. More recently, hearing loss has been shown as a marker of risk for dementia. However, it is not known whether this association represents a causal impact of hearing loss, nor whether treating hearing loss may help prevent dementia. Most studies on relationships between hearing loss and cognitive outcomes are observational, are at risk of confounding, and cannot reach conclusions about causation. A recent high quality randomized controlled trial, relatively uncommon in audiology, reported no impact of a comprehensive hearing intervention in mitigating cognitive decline in older adults. Although secondary analysis revealed potential benefits in a sub-sample of adults, this finding may be spurious. Encouraging policymakers, patients, and other health care practitioners to address hearing loss in terms of dementia prevention may be inappropriate on the grounds of both relevance at individual level and lack of clear evidence of benefit. In addition, advocating need to address hearing loss in terms of mitigating dementia risk may reduce the importance of addressing hearing loss in its own right. Linking hearing loss to dementia risk may also exacerbate the stigma of hearing loss, inadvertently discouraging people from seeking help for hearing. We suggest that treating hearing loss may have important benefits in preventing or delaying diagnosis of dementia via improving orientation and functioning in daily life, without changing the underlying pathology. Rather than linking hearing loss to dementia risk, we suggest a positive message focusing on the known benefits of addressing hearing loss in terms of improved communication, quality of life, and healthy aging.

Interactive effects of hearing aid use and cognitive function in patients with hearing loss

BACKGROUND

There has been a significant increase in scientific investigations of the hearing-dementia association among the research on potentially modifiable risk factors for cognitive impairment. We tested two clinical questions. Analysis 1: does persistent hearing aid (HA) use decrease the decline in cognitive function caused by ageing? Analysis 2: does cognitive function at the time of HA fitting predict future persistent HA use?

METHODS

This case-control study performed at two referral centres reported data obtained over a 4.5-year period. We recruited a group of patients with cognitive decline, aged 65 or older with or without hearing loss. The intervention consisted of the use of HAs. The primary outcome measures were adherence to continuous HA use and cognitive function measured using the Japanese version of the Mini-Mental State Examination Test and the Reading Cognitive Test Kyoto.

RESULTS

Eighteen HA users and 18 controls were included in the first analysis. HA use was associated with a deceleration of cognitive decline 12 months later. In the second analysis, 11 participants with good adherence to HA use were compared with 12 participants who showed poor adherence to HA use. Among the variables employed in this study, cognitive function measured using the Reading Cognitive Test Kyoto was significantly lower in participants with poor adherence to HA.

CONCLUSIONS

HA use in cognitively impaired individuals with hearing loss can slow age-related cognitive decline. Cognitively impaired people with hearing loss who fail to commit to HA use tend to have lower cognitive measurement scores before HA fitting. HA use is generally more challenging as people age and their cognitive abilities decline. Therefore, it is desirable that HAs be used when hearing loss and dementia are in their early stages.

The emerging roles and therapeutic implications of immunosenescence-mediated inflammaging in age-related hearing loss

Age-related hearing loss (ARHL) represents one of the most prevalent chronic sensory deficits experienced by the elderly, significantly diminishing their quality of life and correlating with various medical and psychological morbidities. This condition arises from the cumulative effects of aging on the auditory system, implicating intricate interactions between genetic predispositions and environmental factors. Aging entails a progressive decline in immune system functionality, termed immunosenescence, leading to a chronic low-grade inflammation known as inflammaging. This phenomenon potentially serves as a common mechanism underlying ARHL and other age-related pathologies. Recent research suggests that rejuvenating immunosenescence could mitigate inflammaging and ameliorate age-related functional declines, offering promising insights into anti-aging therapies. Consequently, this review endeavors to elucidate the role of immunosenescence-mediated inflammaging in ARHL progression and discuss its therapeutic implications.

Relationship of Hearing Loss to Parkinson's Disease, Dementia, and APOE Genotype in Adults

Background: Hearing loss has been recognized as a risk factor for dementia and non-motor features of Parkinson's disease (PD). The apolipoprotein E (APOE) protein contributes to maintenance and repair of neuronal cell membranes, causing age-related disorders. This study aimed to analyze the impact of hearing loss on cognitive impairment, PD severity, and APOE gene expression in these patients. Methods: A total of 72 out-patients diagnosed with either PD or hearing loss were enrolled in this study. The hearing assessment included pure-tone audiometry, speech reception thresholds, and speech discrimination ability. Dementia was assessed by filling out the Clinical Dementia Rating and Mini-Mental State Examination questionnaires. The severity of PD was assessed using the Modified Hoehn and Yahr scale. Blood samples were tested for the gene expression of APOE. Results: Out of the 72 cases, there were 44 males and 28 females, with an average age of 64.4 ± 9.1 years. A total of 41 out of 72 cases had dementia and had a worse hearing threshold than those without dementia (47.1 ± 24.4 vs. 31.7 ± 22.1 dB, p = 0.006). A total of 58 patients were diagnosed with PD, with 14 of them classified as having severe symptoms (Modified Hoehn and Yahr scale > 2). Patients with severe PD were found to have a worse hearing threshold (49.6 ± 28.3 vs. 30.3 ± 17.8 dB, p = 0.028) and higher prevalence of dementia (12/14 vs. 18/44, p = 0.006). Among 10 individuals with the APOE ε4 gene, the prevalence of dementia was higher than those without the ε4 allele (9/10 vs. 32/62, p = 0.036). Conclusions: Hearing loss is common in severe PD and in dementia patients. Severe PD has a negative impact on the hearing threshold and cognitive dysfunction. Patients with APOE ε4 have a higher prevalence of dementia.

Cross-sectional associations between multisensory impairment and brain volumes in older adults: Baltimore Longitudinal Study of Aging

Sensory impairment and brain atrophy is common among older adults, increasing the risk of dementia. Yet, the degree to which multiple co-occurring sensory impairments (MSI across vision, proprioception, vestibular function, olfactory, and hearing) are associated with brain morphometry remain unexplored. Data were from 208 cognitively unimpaired participants (mean age 72 ± 10 years; 59% women) enrolled in the Baltimore Longitudinal Study of Aging. Multiple linear regression models were used to estimate cross-sectional associations between MSI and regional brain imaging volumes. For each additional sensory impairment, there were associated lower orbitofrontal gyrus and entorhinal cortex volumes but higher caudate and putamen volumes. Participants with MSI had lower mean volumes in the superior frontal gyrus, orbitofrontal gyrus, superior parietal lobe, and precuneus compared to participants with < 2 impairments. While MSI was largely associated with lower brain volumes, our results suggest the possibility that MSI was associated with higher basal ganglia volumes. Longitudinal analyses are needed to evaluate the temporality and directionality of these associations.

Hearing Difficulties Among Farmworkers in the México-US Southwest Border Region

Migrant and seasonal farmworkers are a vulnerable population with a potentially high risk for hearing loss due to farm-related noise exposures. Occupational noise-induced hearing loss (NIHL) is permanent, and it is associated with an increased risk for injuries on the job, as well as communication difficulties, isolation, and depression. The México/US border region is one of the most productive agricultural regions in the country, however, no known studies have explored hearing loss among farmworkers in this area. This pilot study was a first step toward measuring and addressing hearing loss and noise exposure among this region's farmworkers. We conducted a cross-sectional survey to estimate the prevalence of subjective hearing difficulties among Yuma County, Arizona farmworkers. Survey interviews took place during a late-night farmworker health fair from 2 am to 6 am to accommodate local farms' labor schedules. Multivariable regression adjusted for demographic and work covariates estimated subjective hearing loss prevalence ratios. Among 132 farmworker participants, 36% reported they have or might have hearing loss, and 62% reported no hearing loss. Subjective hearing loss prevalence was lower in farmworkers who report not working in noise compared to prevalence in farmworkers who work in noise [prevalence ratio, 0.44 (95% CI 0.23-0.82)]. This report contributes to understanding the perception of hearing-related health and occupational exposures among farmworkers in the México-US Southwest border region. The information from this line of research will inform appropriate safety measures known to lower the risk of experiencing occupational NIHL.

The Association between Untreated and Treated Hearing Loss and Cognitive Performance in Men and Women Aged 60-96 Years: Data from the Swedish "Good Aging in Skåne" Population Study

Background/Objectives: Recent decades have witnessed a sharp increase in research investigating the association between hearing loss and cognitive impairment. Few previous studies have stratified for sex when investigating this issue, where results were inconsistent and require further clarification. Thus, the objective was to investigate the association between self-reported hearing loss and levels of cognitive impairment, stratified for sex. Methods: In this cross-sectional study, data were collected from 2001 to 2016. The study sample consisted of 5075 individuals, 2325 (45.8%) men, mean age 68.3 years, and 2750 (54.2%) women, mean age 70.0 years. Multiple variate ordinal regression models were constructed and adjusted for age, marital status, education, physical activity, depressive mood, hypertension, stroke, diabetes, and use of sedatives to investigate associations between groups of self-reported untreated and treated hearing loss and those reporting no hearing loss in relation to levels of cognitive impairment assessed by the Mini-Mental State Examination scale. Results: In men, treated hearing loss was associated with levels of cognitive impairment, odds ratio (OR) = 1.64, 95% confidence interval (CI) = 1.14-2.36. In women, both untreated hearing loss, (OR = 1.45, CI 1.07-1.98) and treated hearing loss (OR= 1.46, CI 1.06-2.04) were associated with levels of cognitive impairment. Conclusions: Hearing loss was found to be associated with cognitive impairment despite hearing aid use as well as awareness amongst physicians. The introduction of screening programs for hearing loss in older adults could be a crucial step for earlier identification of individuals at higher risk of developing cognitive impairment and dementia.

Age-related hearing loss is not linked to cerebrospinal fluid levels of β-amyloid or p-tau181

INTRODUCTION

As Hearing loss and dementia affect people with the same profile, several epidemiological studies have evaluated their relationship. However, the link between age-related hearing loss and Alzheimer's disease is still unclear.

METHODS

We selected subjects with no history of exposure to loud noises, blasts, head trauma with hearing loss, or sudden sensorineural hearing loss from a cohort intended to study preclinical phases of Alzheimer's disease. Participants are volunteers over 55 years without cognitive impairment. We correlated the results of an objective auditory evaluation with brain amyloid and p-tau181 levels and with the outcomes of a comprehensive neuropsychological assessment.

RESULTS

Fifty-five subjects at different stages of the Alzheimer's disease continuum were evaluated. There were no statistically significant correlations between amyloid-β and p-tau levels and any of the objective auditory measures. A weak but significant correlation was found between amyloid-β values and the Hearing Handicap Inventory for the Elderly. The neuropsychological domains more correlated to hearing loss were executive function and processing speed.

DISCUSSION

Age-related hearing loss is not linked to any pathological markers of Alzheimer's disease nor to neuropsychological domains typically affected in this disease. The Hearing Handicap Inventory for the Elderly has an important component of subjectivity and further studies are needed to explore its relationship with amyloid-β levels.

Sensory and motor deficits as contributors to early cognitive impairment

INTRODUCTION

Age-related sensory and motor impairment are associated with risk of dementia. No study has examined the joint associations of multiple sensory and motor measures on prevalence of early cognitive impairment (ECI).

METHODS

Six hundred fifty participants in the Baltimore Longitudinal Study of Aging completed sensory and motor function tests. The association between sensory and motor function and ECI was examined using structural equation modeling with three latent factors corresponding to multisensory, fine motor, and gross motor function.

RESULTS

The multisensory, fine, and gross motor factors were all correlated (r = 0.74 to 0.81). The odds of ECI were lower for each additional unit improvement in the multisensory (32%), fine motor (30%), and gross motor factors (12%).

DISCUSSION

The relationship between sensory and motor impairment and emerging cognitive impairment may guide future intervention studies aimed at preventing and/or treating ECI.

HIGHLIGHTS

Sensorimotor function and early cognitive impairment (ECI) prevalence were assessed via structural equation modeling. The degree of fine and gross motor function is associated with indicators of ECI. The degree of multisensory impairment is also associated with indicators of ECI.

GDF1 ameliorates cognitive impairment induced by hearing loss

Hearing loss is associated with an increased risk of Alzheimer disease (AD). However, the mechanisms of hearing loss promoting the onset of AD are poorly understood. Here we show that hearing loss aggravates cognitive impairment in both wild-type mice and mouse models of AD. Embryonic growth/differentiation factor 1 (GDF1) is downregulated in the hippocampus of deaf mice. Knockdown of GDF1 mimics the detrimental effect of hearing loss on cognition, while overexpression of GDF1 in the hippocampus attenuates the cognitive impairment induced by deafness. Strikingly, overexpression of GDF1 also attenuates cognitive impairment in APP/PS1 transgenic mice. GDF1 activates Akt, which phosphorylates asparagine endopeptidase and inhibits asparagine endopeptidase-induced synaptic degeneration and amyloid-β production. The expression of GDF1 is downregulated by the transcription factor CCAAT-enhancer binding protein-β. These findings indicate that hearing loss could promote AD pathological changes by inhibiting the GDF1 signaling pathway; thus, GDF1 may represent a therapeutic target for AD.

Longitudinal Policy Surveillance of Private Insurance Hearing Aid Mandates in the United States: 1997-2022

Objectives. To produce a database of private insurance hearing aid mandates in the United States and quantify the share of privately insured individuals covered by a mandate. Methods. We used health-related policy surveillance methods to create a database of private insurance hearing aid mandates through January 2023. We coded salient features of mandates and combined policy data with American Community Survey and Medicare Expenditure Panel Survey-Insurance Component data to estimate the share of privately insured US residents covered by a mandate from 2008 to 2022. Results. A total of 26 states and 1 territory had private insurance hearing aid mandates. We found variability for mandate exceptions, maximum age eligibility, allowable frequency of benefit use, and coverage amounts. Between 2008 and 2022 the proportion of privately insured youths (aged ≤ 18 years) living where there was a private insurance hearing aid mandate increased from 3.4% to 18.7% and the proportion of privately insured adults (19-64 years) increased from 0.3% to 4.6%. Conclusions. Hearing aid mandates cover a small share of US residents. Mandate exceptions in several states limit coverage, particularly for adults. Public Health Implications. A federal mandate would improve hearing aid access. States can also improve access by adopting exception-free mandates with limited utilization management and no age restrictions. (Am J Public Health. 2024;114(4):407-414. https://doi.org/10.2105/AJPH.2023.307551).

Sound-localization-related activation and functional connectivity of dorsal auditory pathway in relation to demographic, cognitive, and behavioral characteristics in age-related hearing loss

Background

Patients with age-related hearing loss (ARHL) often struggle with tracking and locating sound sources, but the neural signature associated with these impairments remains unclear.

Materials and methods

Using a passive listening task with stimuli from five different horizontal directions in functional magnetic resonance imaging, we defined functional regions of interest (ROIs) of the auditory "where" pathway based on the data of previous literatures and young normal hearing listeners (n = 20). Then, we investigated associations of the demographic, cognitive, and behavioral features of sound localization with task-based activation and connectivity of the ROIs in ARHL patients (n = 22).

Results

We found that the increased high-level region activation, such as the premotor cortex and inferior parietal lobule, was associated with increased localization accuracy and cognitive function. Moreover, increased connectivity between the left planum temporale and left superior frontal gyrus was associated with increased localization accuracy in ARHL. Increased connectivity between right primary auditory cortex and right middle temporal gyrus, right premotor cortex and left anterior cingulate cortex, and right planum temporale and left lingual gyrus in ARHL was associated with decreased localization accuracy. Among the ARHL patients, the task-dependent brain activation and connectivity of certain ROIs were associated with education, hearing loss duration, and cognitive function.

Conclusion

Consistent with the sensory deprivation hypothesis, in ARHL, sound source identification, which requires advanced processing in the high-level cortex, is impaired, whereas the right-left discrimination, which relies on the primary sensory cortex, is compensated with a tendency to recruit more resources concerning cognition and attention to the auditory sensory cortex. Overall, this study expanded our understanding of the neural mechanisms contributing to sound localization deficits associated with ARHL and may serve as a potential imaging biomarker for investigating and predicting anomalous sound localization.

Improving rehabilitation of deaf patients by advanced imaging before cochlear implantation

INTRODUCTION

Cochlear implants have advanced the management of severe to profound deafness. However, there is a strong disparity in hearing performance after implantation from one patient to another. Moreover, there are several advanced kinds of imaging assessment before cochlear implantation. Microstructural white fiber degeneration can be studied with Diffusion weighted MRI (DWI) or tractography of the central auditory pathways. Functional MRI (fMRI) allows us to evaluate brain function, and CT or MRI segmentation to better detect inner ear anomalies.

OBJECTIVE

This literature review aims to evaluate how helpful pre-implantation anatomic imaging can be to predict hearing rehabilitation outcomes in deaf patients. These techniques include DWI and fMRI of the central auditory pathways, and automated labyrinth segmentation by CT scan, cone beam CT and MRI.

DESIGN

This systematic review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Studies were selected by searching in PubMed and by checking the reference lists of relevant articles. Inclusion criteria were adults over 18, with unilateral or bilateral hearing loss, who had DWI acquisition or fMRI or CT/ Cone Beam CT/ MRI image segmentation.

RESULTS

After reviewing 172 articles, we finally included 51. Studies on DWI showed changes in the central auditory pathways affecting the white matter, extending to the primary and non-primary auditory cortices, even in sudden and mild hearing impairment. Hearing loss patients show a reorganization of brain activity in various areas, such as the auditory and visual cortices, as well as regions involved in language and emotions, according to fMRI studies. Deep Learning's automatic segmentation produces the best CT segmentation in just a few seconds. MRI segmentation is mainly used to evaluate fluid space of the inner ear and determine the presence of an endolymphatic hydrops.

CONCLUSION

Before cochlear implantation, a DWI with tractography can evaluate the central auditory pathways up to the primary and non-primary auditory cortices. This data is then used to generate predictions on the auditory rehabilitation of patients. A CT segmentation with systematic 3D reconstruction allow a better evaluation of cochlear malformations and predictable difficulties during surgery.

Cochlear implantation in older adults: 15 years' experience of a tertiary centre in a developing country

INTRODUCTION

Cochlear implant (CI) is a viable option of treatment for older patients with severe to profound deafness in resource-rich countries. Implantation is limited in developing countries.

OBJECTIVE

To review factors and outcomes of elderly patients that underwent CI in a pioneer centre in a developing country.

MATERIAL AND METHODS

An observational retrospective review of patients older than 60, implanted between 2005 to 2020.

RESULTS

Eleven patients were included. Patient were aged 60-74 years old with median of 66 years old. Average duration of deafness prior to implantation is 22 years. All implantation was unilateral except for one case that was implanted sequentially after 5 years Three patients were privately funded. Analysis of the hearing aided level with CI and hearing aid showed substantial improvement provided by the CI. The Categories of Auditory performance (CAP-II) scale were in the range of 6-9.

DISCUSSION

Cochlear implant is safe and stable intervention in providing improvement of hearing and self-esteem in the elderly patients. Social isolation and depression also improved with better hearing and communication.

CONCLUSION

Awareness of the CI in elderly patients must be advocated among policy- makers, clinicians, and patients to mitigate the clinical and public health burden of hearing loss among older patients.

Hearing loss and dementia in older adults: A narrative review

The prevalence of hearing loss is high among older adults; globally, 65% of adults over 60 years have hearing loss. Over the past decade, evidence from epidemiologic studies has linked hearing loss to nearly two times greater risk of dementia. The hypothesized mechanistic pathways through which hearing loss could contribute to increased dementia risk include the effects of hearing on greater cognitive load, changes in brain structure and function, and decreased social engagement. These mechanistic pathways may be modified by management of hearing loss using existing intervention (eg, hearing aids). Hearing treatment may be an effective intervention for slowing cognitive decline in some older adults. In this review, we update existing reviews of the current epidemiologic research on the association between hearing loss and dementia risk and discuss hypothesized mechanisms of this association. We also discuss management of hearing loss as a potential intervention for slowing cognitive decline and reducing dementia risk.

Associations of hearing loss and structural changes in specific cortical regions: a Mendelian randomization study

INTRODUCTION

Previous studies have suggested a correlation between hearing loss (HL) and cortical alterations, but the specific brain regions that may be affected are unknown.

METHODS

Genome-wide association study (GWAS) data for 3 subtypes of HL phenotypes, sensorineural hearing loss (SNHL), conductive hearing loss, and mixed hearing loss, were selected as exposures, and GWAS data for brain structure-related traits were selected as outcomes. The inverse variance weighted method was used as the main estimation method.

RESULTS

Negative associations were identified between genetically predicted SNHL and brain morphometric indicators (cortical surface area, cortical thickness, or volume of subcortical structures) in specific brain regions, including the bankssts (β = -0.006 mm, P = 0.016), entorhinal cortex (β = -4.856 mm2, P = 0.029), and hippocampus (β = -24.819 cm3, P = 0.045), as well as in brain regions functionally associated with visual perception, including the pericalcarine (β = -10.009 cm3, P = 0.013).

CONCLUSION

Adaptive changes and functional remodeling of brain structures occur in patients with genetically predicted HL. Brain regions functionally associated with auditory perception, visual perception, and memory function are the main brain regions vulnerable in HL.

Neuroimaging Characteristics of Hearing Loss in the Mayo Clinic Study of Aging

OBJECTIVE

To investigate the association between standard pure tone and speech audiometry with neuroimaging characteristics reflective of aging and dementia in older adults.

STUDY DESIGN

Prospective population-based study.

SETTING

Single tertiary care referral center.

METHODS

Participants from the Mayo Clinic Study of aging 60 years old or older with normal cognition or mild cognitive impairment, baseline neuroimaging, and a behavioral audiogram associated with neuroimaging were eligible for study. Imaging modalities included structural MRI (sMRI) and fluid-attenuated inversion recovery MRI (FLAIR-MRI; N = 605), diffusion tensor imaging MRI (DTI-MRI; N = 444), and fluorodeoxyglucose-positron emission tomography (FDG-PET; N = 413). Multivariable logistic and linear regression models were used to evaluate associations with neuroimaging outcomes.

RESULTS

Mean (SD) pure tone average (PTA) was 33 (15) dB HL and mean (SD) word recognition score (WRS) was 91% (14). There were no significant associations between audiometric performance and cortical thinning assessed by sMRI. Each 10-dB increase in PTA was associated with increased likelihood of abnormal white-matter hyperintensity (WMH) from FLAIR-MRI (odds ratio 1.26, P = .02). From DTI-MRI, participants with <100% WRSs had significantly lower fractional anisotropy in the genu of the corpus callosum (parameter estimate [PE] -0.012, P = .008) compared to those with perfect WRSs. From FDG-PET, each 10% decrease in WRSs was associated with decreased uptake in the anterior cingulate cortex (PE -0.013, P = .001).

CONCLUSION

Poorer audiometric performance was not significantly associated with cortical thinning but was associated with white matter damage relevant to cerebrovascular disease (increased abnormal WMH, decreased corpus callosum diffusion). These neuroimaging results suggest a pathophysiologic link between hearing loss and cerebrovascular disease.

Association of Thallium with Diabetes Risk among Patients with Hearing Loss: Result from NHANES 2013 to 2018

To evaluate the correlation between thallium and diabetes risk among participants with hearing loss. This retrospective cohort study extracted related data such as demographic characteristics, lifestyle factors, and laboratory findings from the National Health and Nutrition Examination Survey (NHANES) database (2013-2018). Logistic regression analysis and interaction analysis were adopted to analyze the correlation between thallium and diabetes risk among patients with hearing loss. Then, the restricted cubic spline was employed to assess the nonlinear relationship between thallium and diabetes risk. The receiver operating characteristic curve and decision curve analysis were used to assess the predictive values of 3 multivariate models with or without thallium for diabetes risk. The Delong test was adopted to assess the significant change of the area under the curves (AUCs) upon thallium addition. A total of 425 participants with hearing loss were enrolled in the study: without diabetes group (n = 316) and diabetes group (n = 109). Patients with hearing loss in the diabetes group had significantly lower thallium (P < .05). The thallium was an independent predictor for diabetes risk after adjusting various covariates (P < .05). The restricted cubic spline (RCS) result showed that there was a linear correlation between thallium and diabetes risk (P nonlinear > .05). Finally, the receiver operating characteristic and decision curve analysis results revealed that adding thallium to the models slightly increased the performance in predicting diabetes risk but without significance in AUC change. Thallium was an independent predictor of diabetes risk among patients with hearing loss. The addition of thallium might help improve the predictive ability of models for risk reclassification. However, the conclusions should be verified in our cohort in the future due to the limitations inherent in the NHANES database.

Elderly Individuals Residing in Nursing Homes in Western Romania Who Have Been Diagnosed with Hearing Loss are at a Higher Risk of Experiencing Cognitive Impairment

Purpose

The objective of this research was to determine if there is any correlation between the severity of neurocognitive disorder and hearing impairment in the elderly.

Patients and Methods

This is a population-based observational study that included subjects aged ≥ 65 years. They were evaluated for the existence of cardiovascular risk factors, diabetes, stroke, alcohol abuse, and smoking. Hearing impairment was diagnosed by an audiologist, using behavioral audiometric examination. These evaluations might have been performed in response to concerns about hearing loss, or they could have been a routine component of yearly comprehensive health screenings that included a Mini-Mental State Examination 2nd Edition (MMSE-2) test. According to the results of the MMSE-2 scale, we divided the individuals into two groups, Group I for those who had cognitive impairment and severe neurocognitive disorder, and Group II for those who did not have cognitive impairment.

Results

The study enrolled 203 patients with a mean age of 77 ± 7.5 years (range 65-98), 99 (48%) were males. When comparing the two groups, group I patients presented more often cardiovascular risk factors, stroke, diabetes, and impaired hearing. The univariable logistic regression found that cognitive impairment was significantly more frequent in the elderly with cardiovascular disease, diabetes, and stroke (p<0.0001). The multivariate regression analysis found that stroke (p<0.0001) diabetes (p=0.0008), cardiovascular disease (p=0.0004), and impaired hearing (p=0.0011) were significantly linked to cognitive impairment. The occurrence of hearing impairment in the elderly was related to having an MMSE-2 score of 14 or below.

Conclusion

According to the findings of this research, the elderly who have trouble hearing in addition to other conditions might have an increased risk for severe neurocognitive disorder.

Brain Dynamics Complexity as a Signature of Cognitive Decline in Parkinson's Disease

BACKGROUND

Higuchi's fractal dimension (FD) captures brain dynamics complexity and may be a promising method to analyze resting-state functional magnetic resonance imaging (fMRI) data and detect the neuronal interaction complexity underlying Parkinson's disease (PD) cognitive decline.

OBJECTIVES

The aim was to compare FD with a more established index of spontaneous neural activity, the fractional amplitude of low-frequency fluctuations (fALFF), and identify through machine learning (ML) models which method could best distinguish across PD-cognitive states, ranging from normal cognition (PD-NC), mild cognitive impairment (PD-MCI) to dementia (PDD). Finally, the aim was to explore correlations between fALFF and FD with clinical and cognitive PD features.

METHODS

Among 118 PD patients age-, sex-, and education matched with 35 healthy controls, 52 were classified with PD-NC, 46 with PD-MCI, and 20 with PDD based on an extensive cognitive and clinical evaluation. fALFF and FD metrics were computed on rs-fMRI data and used to train ML models.

RESULTS

FD outperformed fALFF metrics in differentiating between PD-cognitive states, reaching an overall accuracy of 78% (vs. 62%). PD showed increased neuronal dynamics complexity within the sensorimotor network, central executive network (CEN), and default mode network (DMN), paralleled by a reduction in spontaneous neuronal activity within the CEN and DMN, whose increased complexity was strongly linked to the presence of dementia. Further, we found that some DMN critical hubs correlated with worse cognitive performance and disease severity.

CONCLUSIONS

Our study indicates that PD-cognitive decline is characterized by an altered spontaneous neuronal activity and increased temporal complexity, involving the CEN and DMN, possibly reflecting an increased segregation of these networks. Therefore, we propose FD as a prognostic biomarker of PD-cognitive decline. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

New Age Hearing Testing at your Fingertips: Shravana Mitra App

INTRODUCTION

WHO estimated the prevalence of disabling hearing loss is 5% of the world population (430 million). People with a risk of hearing loss from noise exposure, ototoxic drugs, and comorbidities need regular hearing assessments. It is done by pure tone audiometry (PTA), requiring a skilled audiologist, special equipment, and a soundproof room. Modern technologies can help in overcoming these barriers. This study aimed to fill the lacuna by developing a new android-based application "Shravana Mitra" (Hearing companion) with features of both air conduction (AC) and bone conduction (BC) testing.

OBJECTIVES

To develop, corroborate and compare smartphone application-based audiometry with PTA.

METHODOLOGY

This study was done in three phases -(i) development of a mobile application, (ii) app validation in healthy individuals (iii) testing and comparison of results with PTA in individuals visiting OPD. The third phase was done as a cross-sectional observational study including 780 individuals visiting OPD of 10-60 years of age.

RESULTS

The mean age of the study population was 32.89 years with female preponderance (57%). In AC testing, 83% of the pure tone average of the mobile application was within 5 dB of PTA thresholds and 99% was within 10 dB and for BC testing, 81% was within 5 dB of PTA thresholds and 98% within 10 dB.

CONCLUSION

Our user-friendly mobile application- Shravana Mitra is the first Indian application available in the google play store with both AC & BC testing, multiple language options and accuracy similar to PTA. Thus, it can be used as the best hearing screening tool in camps, high-risk individuals, or any healthcare setup requiring initial hearing assessment.

Associations between multimorbidity burden and Alzheimer's pathology in older adults without dementia: the CABLE study

Studies have shown that multimorbidity may be associated with the Alzheimer's disease (AD) stages, but it has not been fully characterized in patients without dementia. A total of 1402 Han Chinese older adults without dementia from Chinese Alzheimer's Biomarker and LifestylE (CABLE) study were included and grouped according to their multimorbidity patterns, defined by the number of chronic disorders and cluster analysis. Multivariable linear regression models were used to detect the associations with AD-related cerebrospinal fluid (CSF) biomarkers. Multimorbidity and severe multimorbidity (≥4 chronic conditions) were significantly associated with CSF amyloid and tau levels (pFDR < 0.05). Metabolic patterns were significantly associated with higher levels of CSF Aβ40 (β = 0.159, pFDR = 0.036) and tau (P-tau: β = 0.132, pFDR = 0.035; T-tau: β = 0.126, pFDR = 0.035). The above associations were only significant in the cognitively normal (CN) group. Multimorbidity was associated with brain AD pathology before any symptomatic evidence of cognitive impairment. Identifying such high-risk groups might allow tailored interventions for AD prevention.

Hearing Loss, Hearing Aid Use, and Risk of Dementia in Older Adults

Importance

Hearing loss has been suggested as a risk factor for dementia, but there is still a need for high-quality research to better understand the association between these 2 conditions and the underlying causal mechanisms and treatment benefits using larger cohorts and detailed data.

Objective

To investigate the association between hearing loss and incident dementia, as well as how hearing aid use contributes to this association.

Design, Setting, and Participants

This population-based cohort study was conducted in Southern Denmark between January 2003 and December 2017 and included all residents 50 years and older. We excluded all persons with dementia before baseline as well as those who did not live in the region 5 years before baseline, with incomplete address history, or who had missing covariate information.

Exposures

Individual hearing status based on the Hearing Examinations in Southern Denmark database, which contains data on all pure-tone audiometry examinations performed at public hearing rehabilitation clinics in Southern Denmark.

Main Outcomes and Measures

Incident cases of dementia and Alzheimer disease as identified from national registries.

Results

The study population comprised 573 088 persons (298 006 women [52%]; mean [SD] age, 60.8 [11.3] years) with 23 023 cases of dementia and mean (SD) follow-up of 8.6 (4.3) years. Having a hearing loss was associated with an increased risk of dementia, with an adjusted hazard ratio (HR) of 1.07 (95% CI, 1.04-1.11) compared with having no hearing loss. Severe hearing loss in the better and worse ear was associated with a higher dementia risk, with an HR of 1.20 (95% CI, 1.09-1.32) and 1.13 (95% CI, 1.06-1.20), respectively, compared with having no hearing loss in the corresponding ear. Compared with people without hearing loss, the risk of dementia was higher among people with hearing loss who were not using hearing aids than those who had hearing loss and were using hearing aids, with HRs of 1.20 (95% CI, 1.13-1.27) and 1.06 (95% CI, 1.01-1.10), respectively.

Conclusions and Relevance

The results of this cohort study suggest that hearing loss was associated with increased dementia risk, especially among people not using hearing aids, suggesting that hearing aids might prevent or delay the onset and progression of dementia. The risk estimates were lower than in previous studies, highlighting the need for more high-quality longitudinal studies.

Hearing Aids and Quality of Life: A Psychological Perspective

Objective

This research assessed the relationship between hearing aid usage and quality of life in individuals with hearing impairment, exploring associated demographic and clinical factors.

Methodology

Data from 500 individuals at a tertiary care facility were collected over a year through medical records and an online questionnaire. Quality of life was gauged using WHOQOL-BREF and HHIE. Multiple linear regression analysed the correlation between hearing aid usage and quality of life, adjusting for age, gender, hearing loss severity, and socioeconomic factors.

Results

Descriptive statistics showed varying degrees of hearing impairment, socioeconomic status, hearing aid usage, and quality-of-life scores. Bivariate analyses found significant correlations between hearing impairment level, socioeconomic status, hearing aid usage, and quality of life. Linear regression highlighted a positive relationship between daily hearing aid usage duration and quality-of-life scores, even after adjusting for covariates. Variations in quality-of-life ratings were observed between hearing aid users and non-users, spanning different hearing loss levels and socioeconomic statuses. Subgroup analysis showed a positive correlation between hearing aid use and quality of life across age groups.

Conclusion

The study confirms the positive influence of hearing aids on the quality of life in hearing-impaired individuals, emphasizing the benefits of consistent use. Further studies should probe the specific domains and long-term adherence impacts.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12070-023-04297-w.

ENHANCE: a comparative prospective longitudinal study of cognitive outcomes after 3 years of hearing aid use in older adults

Background

With an aging population, the prevalence of hearing loss and dementia are increasing rapidly. Hearing loss is currently considered the largest potentially modifiable risk factor for dementia. The effect of hearing interventions on cognitive function should therefore be investigated, as if effective, these may be successfully implemented to modify cognitive outcomes for older adults with hearing loss.

Methods

This prospective longitudinal observational cohort study compared outcomes of a convenience sample of prospectively recruited first-time hearing aid users without dementia from an audiology center with those of community-living older adults participating in a large prospective longitudinal cohort study with/without hearing loss and/or hearing aids. All participants were assessed at baseline, 18 months, and 36 months using the same measures.

Results

Participants were 160 audiology clinic patients (48.8% female patient; mean age 73.5 years) with mild-severe hearing loss, fitted with hearing aids at baseline, and 102 participants of the Australian Imaging, Biomarkers and Lifestyle Flagship Study of Aging (AIBL) (55.9% female patient; mean age 74.5 years). 18- and 36-month outcomes of subsets of the first participants to reach these points and complete the cognition assessment to date are compared. Primary comparative analysis showed cognitive stability for the hearing aid group while the AIBL group declined on working memory, visual attention, and psychomotor function. There was a non-significant trend for decline in visual learning for the AIBL group versus no decline for the hearing aid group. The hearing aid group showed significant decline on only 1 subtest and at a significantly slower rate than for the AIBL participants (p < 0.05). When education effects on cognitive trajectory were controlled, the HA group still performed significantly better on visual attention and psychomotor function (lower educated participants only) compared to the AIBL group but not on working memory or visual learning. Physical activity had no effect on cognitive performance trajectory.

Conclusion

Hearing aid users demonstrated significantly better cognitive performance to 3 years post-fitting, suggesting that hearing intervention may delay cognitive decline/dementia onset in older adults. Further studies using appropriate measures of cognition, hearing, and device use, with longer follow-up, are required.

Evaluating the Impact of Virtual Reality on the Behavioral and Psychological Symptoms of Dementia and Quality of Life of Inpatients With Dementia in Acute Care: Randomized Controlled Trial (VRCT)

BACKGROUND

Virtual reality (VR) is increasingly considered a valuable therapeutic tool for people with dementia. However, rigorous studies are still needed to evaluate its impact on behavioral and psychological symptoms of dementia (BPSDs) and quality of life (QoL) across care settings.

OBJECTIVE

The primary aim of this study was to evaluate the impact of VR therapy on managing BPSDs, falls, length of stay, and QoL in inpatients with dementia admitted to an acute care hospital. The secondary aim was to evaluate the intervention's feasibility in terms of acceptability, safety, and patient experience.

METHODS

A prospective, open-label, mixed methods, randomized controlled clinical trial was conducted between April 2019 and March 2020. A total of 69 participants (aged ≥65 years with a diagnosis of dementia and who did not meet the exclusion criteria) were randomly assigned to either the control (n=35, 51%) or VR (n=34, 49%) arm. Participants in the experimental (VR) arm were visited by a researcher and watched 360° VR films on a head-mounted display for up to 20 minutes every 1 to 3 days, whereas individuals in the control arm received standard of care. Instances of daily BPSDs and falls were collected from nurses' daily notes. QoL was measured through semistructured interviews and the Quality of Life in Late-Stage Dementia scale. Structured observations and semistructured interviews were used to measure treatment feasibility. The primary outcomes were analyzed at a 95% significance level based on the intention-to-treat method.

RESULTS

VR therapy had a statistically significant effect on reducing aggressiveness (ie, physical aggression and loud vociferation; P=.01). Substantial impact of VR therapy was not found for other BPSDs (eg, apathy), falls, length of stay, or QoL as measured using the Quality of Life in Late-Stage Dementia scale. The average VR therapy session lasted 6.8 (SD 6.6; range 0-20) minutes, and the intervention was overall an acceptable and enjoyable experience for participants. No adverse events occurred as a result of VR therapy.

CONCLUSIONS

Immersive VR therapy appears to have an effect on aggressive behaviors in patients with dementia in acute care. Although the randomized controlled trial was stopped before reaching the intended sample size owing to COVID-19 restrictions, trends in the results are promising. We suggest conducting future trials with larger samples and, in some cases, more sensitive data collection instruments.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03941119; https://clinicaltrials.gov/study/NCT03941119.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

RR2-10.2196/22406.

Does social isolation mediate the association between hearing loss and cognition in adults? A systematic review and meta-analysis of longitudinal studies

Background

There has been extensive research on the relationship between hearing and cognitive impairment in older adults but little examination of the role of mediating factors. Social isolation is a potential mediator, occurring because of hearing loss, and contributing to accelerated cognitive decline. Previous systematic reviews on this topic area have not considered the temporal nature of hearing loss and cognitive impairment exclusively or examined potential mediators within a longitudinal study design.

Methods

A systematic review was conducted. Electronic searches were performed in Web of Science, PubMed (Medline), Scopus, EMBASE, PsychInfo, and ProQuest (PsychArticles and ProQuest Dissertation and Theses) based on a search string of keywords relating to hearing loss, social isolation, and cognitive impairment/dementia in June 2023. Papers were critically appraised using the CASP checklists for cohort studies. Risk of bias in the selected studies was assessed using the Item Bank for Assessment of Risk of Bias and Precision for Observational Studies of Interventions or Exposures.

Results

Eleven of the 15 included studies provide evidence of a dose-dependent association between hearing threshold (40 dB HL or greater) and later cognitive impairment or incident dementia. Only one study included social isolation as a mediator, which was found to not be a significant contributing factor. The meta-analysis of 5 studies pooled hazard ratio for cognitive impairment due to hearing loss is 1.11 (95% CI: 1.06 to 1.15, p < 0.001). The pooled hazard ratio for incident dementia due to hearing loss was HR 1.21 (95% CI: 1.11 to 1.31, p = 0.002).

Conclusion

The analysis of included studies indicate that hearing threshold level affects later cognitive status or dementia diagnosis. There is not enough evidence to determine the role of social isolation as a mediator. Future epidemiology studies need to measure different elements of social isolation and ensure that hearing and cognition are measured at multiple time points.

Auditory discrimination in aging bilinguals vs. monolinguals with and without hearing loss

Demands for effective assessments of speech perception specific to the aging brain are increasing, as the impacts of hearing loss on an individual's functional health, socialization, and cognition have become more widely recognized. Understanding the mechanisms behind the optimal function of the aging brain in relation to speech and language is challenging, especially in the bilingual population where the language learning and language interference processes could be mistaken for perceptual difficulty. Age-related presbycusis is unavoidable, and the contributions of this sensorineural hearing loss (SNHL) process on impaired speech recognition are not completely understood. This lack of understanding of the effects of aging and bilingual language competency on speech perception can act as a barrier to successful auditory rehabilitation. The present study investigated the effects of aging on vowel sound discrimination in adult listeners (age 50+) with the following characteristics: American English (AE) monolinguals with normal hearing, simultaneous or early sequential Spanish-English (SE) bilinguals with normal hearing, and AE monolinguals with SNHL (AE-SNHL). The goal was to identify the differences in vowel sound discrimination performance between the monolingual and bilingual aging populations to guide future language assessments and intervention processes. English vowel discrimination was assessed using an AXB discrimination task in quiet and using the Quick Speech in Noise (QuickSIN) test. SE bilinguals were outperformed by AE and AE-SNHL monolinguals, suggesting SE bilinguals primarily use their L1 acoustic properties to discriminate speech segments. No significant difference was found in QuickSIN performance between the bilingual and the monolingual groups, but there was a significant difference between AE and AE-SNHL. In conclusion, vowel discrimination was affected by interference with the native language, while performance in the noise condition was affected by hearing loss. The results of this study contribute to our understanding of the age-related speech processing deficits from three different aging groups regarding the cognitive control system.

Interaural and sex differences in the natural evolution of hearing levels in pre-symptomatic and symptomatic carriers of the p.Pro51Ser variant in the COCH gene

Hearing impairment constitutes a significant health problem in developed countries. If hearing loss is slowly progressive, the first signs may not be noticed in time, or remain untreated until the moment the auditory dysfunction becomes more apparent. The present study will focus on DFNA9, an autosomal dominant disorder caused by pathogenic variants in the COCH gene. Although several cross-sectional studies on this topic have been conducted, a crucial need for longitudinal research has been reported by many authors. Longitudinal trajectories of individual hearing thresholds were established as function of age and superimposed lowess curves were generated for 101 female and male carriers of the p.Pro51Ser variant. The average number of times patients have been tested was 2.49 years with a minimum of 1 year and a maximum of 4 years. In addition, interaural and sex differences were studied, as they could modify the natural evolution of the hearing function. The current study demonstrates that, both in female carriers and male carriers, the first signs of hearing decline, i.e. hearing thresholds of 20 dB HL, become apparent as early as the 3rd decade in the highest frequencies. In addition, a rapid progression of SNHL occurs between 40 and 50 years of age. Differences between male and female carriers in the progression of hearing loss are most obvious between the age of 50 and 65 years. Furthermore, interaural discrepancies also manifest from the age of 50 years onwards. High-quality prospective data on the long-term natural evolution of hearing levels offer the opportunity to identify different disease stages in each cochlea and different types of evolution. This will provide more insights in the window of opportunity for future therapeutic intervention trials.

A Pragmatic Clinical Trial of Hearing Screening in Primary Care Clinics: Effect of Setting and Provider Encouragement

OBJECTIVES

The prevalence of hearing loss increases with age. Untreated hearing loss is associated with poorer communication abilities and negative health consequences, such as increased risk of dementia, increased odds of falling, and depression. Nonetheless, evidence is insufficient to support the benefits of universal hearing screening in asymptomatic older adults. The primary goal of the present study was to compare three hearing screening protocols that differed in their level of support by the primary care (PC) clinic and provider. The protocols varied in setting (in-clinic versus at-home screening) and in primary care provider (PCP) encouragement for hearing screening (yes versus no).

DESIGN

We conducted a multisite, pragmatic clinical trial. A total of 660 adults aged 65 to 75 years; 64.1% female; 35.3% African American/Black completed the trial. Three hearing screening protocols were studied, with 220 patients enrolled in each protocol. All protocols included written educational materials about hearing loss and instructions on how to complete the self-administered telephone-based hearing screening but varied in the level of support provided in the clinic setting and by the provider. The protocols were as follows: (1) no provider encouragement to complete the hearing screening at home, (2) provider encouragement to complete the hearing screening at home, and (3) provider encouragement and clinical support to complete the hearing screening after the provider visit while in the clinic. Our primary outcome was the percentage of patients who completed the hearing screening within 60 days of a routine PC visit. Secondary outcomes following patient access of hearing healthcare were also considered and consisted of the percentage of patients who completed and failed the screening and who (1) scheduled, and (2) completed a diagnostic evaluation. For patients who completed the diagnostic evaluation, we also examined the percentage of those who received a hearing loss intervention plan by a hearing healthcare provider.

RESULTS

All patients who had provider encouragement and support to complete the screening in the clinic completed the screening (100%) versus 26.8% with encouragement to complete the screening at home. For patients who were offered hearing screening at home, completion rates were similar regardless of provider encouragement (26.8% with encouragement versus 22.7% without encouragement); adjusted odds ratio of 1.25 (95% confidence interval 0.80-1.94). Regarding the secondary outcomes, roughly half (38.9-57.1% depending on group) of all patients who failed the hearing screening scheduled and completed a formal diagnostic evaluation. The percentage of patients who completed a diagnostic evaluation and received a hearing loss intervention plan was 35.0% to 50.0% depending on the group. Rates of a hearing loss intervention plan by audiologists ranged from 28.6% to 47.5% and were higher compared with those by otolaryngology providers, which ranged from 15.0% to 20.8% among the groups.

CONCLUSIONS

The results of the pragmatic clinical trial showed that offering provider encouragement and screening facilities in the PC clinic led to a significantly higher rate of adherence with hearing screening associated with a single encounter. However, provider encouragement did not improve the significantly lower rate of adherence with home-based hearing screening.

Distinct changes in brain metabolism in patients with dementia and hearing loss

INTRODUCTION

Previous studies have reported that hearing loss (HL) is associated with dementia, although the mechanistic underpinnings remain elusive. This study aimed to evaluate the changes in brain metabolism in patients with HL and different types of dementia.

METHODS

Patients with cognitive impairment (CI) and HL treated at the university-based memory clinic from May 2016 to October 2021 were included. In total, 108 patients with CI and HL prospectively underwent audiometry, neuropsychological test, magnetic resonance imaging, and 18 F-fluorodeoxyglucose positron emission tomography. Twenty-seven individuals without cognitive impairment and hearing loss were enrolled as a control group. Multivariable regression was performed to evaluate brain regions correlated with each pathology type after adjusting for confounding factors.

RESULTS

Multivariable regression analyses revealed that Alzheimer's disease-related CI (ADCI) was associated with hypometabolic changes in the right superior temporal gyrus (STG), right middle temporal gyrus (MTG), and bilateral medial temporal lobe. Lewy body disease-related CI (LBDCI) and vascular CI were associated with hypermetabolic and hypometabolic changes in the ascending auditory pathway, respectively. In the pure ADCI group, the degree of HL was positively associated with abnormal increase of brain metabolism in the right MTG, whereas it was negatively associated with decreased brain metabolism in the right STG in the pure LBDCI group.

CONCLUSION

Each dementia type is associated with distinct changes in brain metabolism in patients with HL.

Trajectories and contributing factors of neural compensation in healthy and pathological aging

Neural degeneration is a hallmark of healthy aging and can be associated with specific cognitive impairments. However, neural degeneration per se is not matched by unremitting declines in cognitive abilities. Instead, middle-aged and older adults typically maintain surprisingly high levels of cognitive functioning, suggesting that the human brain can adapt to structural degeneration by neural compensation. Here, we summarize prevailing theories and recent empirical studies on neural compensation with a focus on often neglected contributing factors, such as lifestyle, metabolism and neural plasticity. We suggest that these factors moderate the relationship between structural integrity and neural compensation, maintaining psychological well-being and behavioral functioning. Finally, we discuss that a breakdown in neural compensation may pose a tipping point that distinguishes the trajectories of healthy vs pathological aging, but conjoint support from psychology and cognitive neuroscience for this alluring view is still scarce. Therefore, future experiments that target the concomitant processes of neural compensation and associated behavior will foster a comprehensive understanding of both healthy and pathological aging.

Functional connectome hierarchy dysfunction in Alzheimer's disease and its relationship with cognition and gene expression profiling

Numerous researches have shown that the human brain organizes as a continuum axis crossing from sensory motor to transmodal cortex. Functional network alterations were commonly found in Alzheimer's disease (AD). Whether the hierarchy of AD brain networks has changed and how these changes related to gene expression profiling and cognition is unclear. Using resting-state functional magnetic resonance imaging data from 233 subjects (185 AD patients and 48 healthy controls), we studied the changes in the functional network gradients in AD. Moreover, we investigated the relationships between gradient alterations and cognition, and gene expression profiling, respectively. We found that the second gradient organizes as a continuum axis crossing from the sensory motor to the transmodal cortex. Compared to the healthy controls, the secondary gradient scores of the visual and somatomotor network (SOM) increased significantly in AD, and the secondary gradient scores of default mode and frontoparietal network decreased significantly in AD. The secondary gradient scores of SOM and salience network (SAL) significantly positively correlated with memory function in AD. The secondary gradient in SAL also significantly positively correlated with language function. The AD-related second gradient alterations were spatially associated with the gene expression and the relevant genes enriched in neurobiology-related pathways, specially expressed in various tissues, cell types, and developmental stages. These findings suggested the changes in the functional network gradients in AD and deepened our understanding of the correlation between macroscopic gradient structure and microscopic gene expression profiling in AD.

Impact of Concurrent Visual and Hearing Impairment on Incident Alzheimer's Disease: The LIFE Study

Background

The prevalence of Alzheimer's disease (AD) is increasing in Japan due to population aging. The association between sensory impairment and incident AD remains unclear.

Objective

This study aimed to investigate the impact of sensory impairment on incident AD.

Methods

We analyzed residents of five municipalities participating in the Longevity Improvement & Fair Evidence (LIFE) Study. The participants comprised individuals who had newly applied for long-term care needs certification between 2017 and 2022 and had no cognitive impairment upon application or AD diagnosis within the preceding six months. Participants were classified according to sensory impairment status: visual impairment (VI), hearing impairment (HI), neither sensory impairment (NSI), and dual sensory impairment (DSI). The month succeeding the certification application was set as the index month, and the interval from that month until AD onset was assessed. Multivariable Cox proportional hazards analysis was performed to calculate the risk of AD onset according to sensory impairment status while adjusting for sex, age, dependence level, self-reliance level, and comorbidities.

Results

Among 14,186 participants, we identified 1,194 (8.4%) who developed AD over a median follow-up period of 22.6 months. VI and HI only were not associated with incident AD. However, DSI conferred a significantly higher risk (HR: 1.6, CI: 1.1-2.2, p = 0.008) of AD onset than NSI.

Conclusions

Individuals with concurrent DSI have a higher risk of developing AD than those with single or NSI. Preventing and treating sensory impairment may not only improve functional outcomes, but could also help to reduce the future risk of AD.

Adjunct Methods for Alzheimer's Disease Detection: A Review of Auditory Evoked Potentials

The auditory afferent pathway as a clinical marker of Alzheimer's disease (AD) has sparked interest in investigating the relationship between age-related hearing loss (ARHL) and AD. Given the earlier onset of ARHL compared to cognitive impairment caused by AD, there is a growing emphasis on early diagnosis and intervention to postpone or prevent the progression from ARHL to AD. In this context, auditory evoked potentials (AEPs) have emerged as a widely used objective auditory electrophysiological technique for both the clinical diagnosis and animal experimentation in ARHL due to their non-invasive and repeatable nature. This review focuses on the application of AEPs in AD detection and the auditory nerve system corresponding to different latencies of AEPs. Our objective was to establish AEPs as a systematic and non-invasive adjunct method for enhancing the diagnostic accuracy of AD. The success of AEPs in the early detection and prediction of AD in research settings underscores the need for further clinical application and study.

Correlations between Dementia and Loneliness

This review describes associations between dementia and loneliness on the neurobiological and epidemiological levels according to the recent body of literature. The aim of this study was to highlight major lines of research in this field. Sociocognitive skills and social interactions present complex interdependencies with dementia which may be explained by two theories. According to the first one, not sufficiently engaging in social or cognitive activities results in brain atrophy. The second one claims that brain neurogenesis and synaptic density are being increased by social connections. The relationship between loneliness and dementia could be mediated by sensory loss, including hearing and visual impairment, as well as depression and psychotic symptoms. Loneliness itself might cause a depletion in sensory and cognitive stimulation which results in a decrease in neural reserve. Certain changes in the structures of the brain caused by loneliness were found in imaging examination. Loneliness appears to be a crucial risk factor for dementia in recent times due to the modern lifestyle and consequences of the outbreak of COVID-19. Additional studies are required to understand more completely the key tenets of this topic and therefore to improve the prevention and treatment of dementia.

Reorganization of the cortical connectome functional gradient in age-related hearing loss

Age-related hearing loss (ARHL), one of the most common sensory deficits in elderly individuals, is a risk factor for dementia; however, it is unclear how ARHL affects the decline in cognitive function. To address this issue, a connectome gradient framework was used to identify critical features of information integration between sensory and cognitive processing centers using resting-state functional magnetic resonance imaging (rs-fMRI) data from 40 individuals with ARHL and 36 healthy controls (HCs). The first three functional gradient alterations associated with ARHL were investigated at the global, network and regional levels. Using a support vector machine (SVM) model, our analysis distinguished individuals with ARHL with normal cognitive function from those with cognitive decline. Compared to HCs, individuals with ARHL had a contracted principal primary-to-transmodal gradient axis, especially in the visual and default mode networks, with an altered gradient explained ratio and variance. Among individuals with ARHL, cognitive decline was detected in the visual network in the principal gradient as well as in the limbic, salience and default mode networks in the third gradient (salience to frontoparietal/default mode). These results suggest that ARHL is associated with disrupted information processing from the primary sensory networks to higher-order cognitive networks and highlight the key nodes closely associated with cognitive decline during cognitive processing in ARHL, providing new insights into the mechanism of cognitive impairment and suggesting potential treatments related to ARHL.

Clinical Assessment Tools for the Detection of Cognitive Impairment and Hearing Loss in the Ageing Population: A Scoping Review

Objective

There is a strong association between cognitive impairment and hearing loss, both highly prevalent in the ageing population. Early detection of both hearing loss and cognitive impairment is essential in the management of these conditions to ensure effective and informed decisions on healthcare. The main objective was to identify existing and emerging cognitive and auditory assessment tools used in clinical settings (eg, memory clinics, audiology clinics), which manage the ageing population.

Methods

A scoping review of peer-reviewed publications and results were reported according to the PRISMA-ScR guidelines.

Results

A total of 289 articles were selected for data extraction. The majority of studies (76.1%) were conducted in 2017 or later. Tests of global cognitive function (ie, Mini-Mental State Exam, Montreal Cognitive Assessment) were the most commonly used method to detect cognitive impairment in hearing healthcare settings. Behavioral hearing testing (ie, pure-tone audiometry) was the most commonly used method to detect hearing loss in cognitive healthcare settings. Objective, physiological measures were seldom used across disciplines.

Conclusion

Preferences among clinicians for short, accessible tests likely explain the use of tests of global cognitive function and behavioral hearing tests. Rapidly evolving literature has identified inherent limitations of administering global cognitive function tests and pure-tone testing in an ageing population. Using electrophysiological measures as an adjunct to standard methods of assessment may provide more reliable information for clinical recommendations in those with cognitive and hearing impairment, and subsequently achieve better healthcare outcomes.

Risk factors associated with occupational noise-induced hearing loss in the Hispanic community health study/study of Latinos: A cross-sectional epidemiologic investigation

The purpose of this study was to estimate the prevalence of occupational noise exposure and risk factors of occupational noise-induced hearing loss (NIHL) in Hispanic/Latino adults included in the baseline wave of the Hispanic Community Health Study/Study of Latinos collected from 2008 to 2011. Sequential multiple linear regression modeled the relationship between occupational NIHL (defined as a 3-, 4-, 6-kHz pure-tone average [PTA]) and occupation type, self-reported noise exposure, cardiovascular disease (CVD) risk score, and hearing protective device (HPD) use. The final model controlled for sex, age, and recreational noise exposure. Among 12,851 included participants, approximately 40% (n = 5036) reported occupational noise exposure "Sometimes" (up to 50% of the time) or "Frequently" (75-100% of the time). In the final fitted model, longest-held occupation and CVD risk were associated with poorer hearing. Specifically, those in non-skilled, service, skilled, and military/police/other job categories had between 2.07- and 3.29-dB worse PTA than professional/office workers. Additionally, a shift in the CVD risk score category from low to medium was associated with a 2.25- and 8.20-dB worse PTA for medium and high CVD risk, respectively. Age and sex were also significantly associated with poorer hearing, such that men presented with 6.08 dB worse PTA than women, and for every one-year increase in age, PTA increased by 0.62 dB (ps < .001). No interactions were seen between noise*sometimes or frequent exposure to other ototoxic agents and PTA (ps = .33 & .92, respectively). The prevalence of occupational noise exposure was high in this cross-sectional investigation of adults from Hispanic/Latino backgrounds. Findings contribute to the extant literature by demonstrating that risk factors for occupational NIHL in adults from varying Hispanic/Latino backgrounds are consistent with those of other previously studied groups.