Age-Related Hearing Loss, Late-Life Depression, and Risk for Incident Dementia in Older Adults

Identification of therapeutic target genes for age-related hearing loss through systematic genome-wide mendelian randomization of druggable genes

BACKGROUND

Age-related hearing loss (ARHL) is a common sensory disorder with significant public health implications. However, few effective treatment options are available. Mendelian randomization (MR) has been used to repurpose existing drugs and identify new therapeutic targets. Therefore, we performed a systematic genome-wide MR of drug-eligible individuals to explore potential therapeutic targets for ARHL.

METHODS

We obtained data on the expression quantitative trait locis (eQTLs) of druggable genes, which were then subjected to two-sample MR analyses and co-localisation analyses with data from the ARHL genome-wide association study to identify genes highly associated with ARHL. Additionally, we conducted phenome-wide research, enrichment analysis, protein network construction, drug prediction, and molecular docking to help develop more effective and targeted therapeutic treatments.

RESULTS

Overall, the MR analysis of eQTL data showed that 14 drug targets were significantly associated with ARHL. GO analysis of 14 potential targets revealed their primary involvement in biological processes such as the endoplasmic reticulum unfolded protein response, ER-nucleus signaling pathway, and fibroblast apoptotic process. Additionally, important cellular components include the Bcl-2 family of proteins and the endoplasmic reticulum lumen. After filtering using methods such as phenome-wide research, enrichment analysis, protein network construction, drug prediction, and molecular docking, six potentially druggable genes (BAK1, AMFR, LAMP3, STK17B, ACP5, and CD9) and six drugs (beclomethasone, propyl pyrazole triol, momelotinib, monoisoamyl-2,3-dimercaptosuccinate, pterostilbene, and naftidrofuryl) that may affect ARHL outcomes were finally identified.

CONCLUSIONS

Our findings identified 14 potential drug targets for ARHL. These findings offer promising leads for more effective treatments for ARHL and help determine the priority of drug development, potentially reducing costs.

The Association Between Hearing Loss and Depression in a Large Electronic Health Record System

OBJECTIVE

Hearing loss (HL) is associated with depression, but existing datasets are limited by the type of data available for both hearing and mental health conditions. The purpose of this study is to determine if there is an association between HL and depressive disorders within a large bi-institutional electronic health record (EHR) system containing more granular diagnostic information.

STUDY DESIGN

Cross-sectional epidemiologic study.

SETTING

Two academic medical centers.

METHODS

Audiometric data was collected from patients ≥18 years old between 2020 to mid-2023 (n = 29,772). The exposure was HL defined as the 4-frequency pure-tone average (PTA), speech reception threshold (SRT), and word recognition score (WRS). The outcomes were depression, categorized as either: (1) major depressive disorder, defined by International Classification of Diseases, 10th Revision (ICD-10) code; (2) persistent mood disorder, defined by ICD-10 code; or (3) antidepressant medication use, defined by medication lists. Odds ratios were computed from logistic regressions between HL and each of the outcome variables, controlling for age, sex, cardiovascular risks, and site.

RESULTS

The mean age (standard deviation) was 60.5 (18.2) years, and 17,736 participants (59.6%) were female. Controlling for covariates, for every 10-dB worsening in hearing by PTA, the odds of major depressive disorder increased by 1.04 times (95% confidence interval [CI] = 1.01-1.07, P = .015). Similarly, for every 10 dB worsening in hearing by PTA or SRT, the odds of antidepressant medication use increased by 1.04 times (95% CI = 1.01-1.06, P = .004). Odds ratios for persistent mood disorder were nonsignificant.

CONCLUSION

In a large academic EHR, HL is associated with major depressive disorder and antidepressant medication use.

Association between age-related hearing loss and depression: A systematic review and meta-analysis

INTRODUCTION

This meta-analysis examined the relationship between age-related hearing loss (ARHL) and depression in older adults, and further explored whether this relationship is moderated by age and gender.

METHODS

We searched in 4 English databases: PubMed, Embase, Web of Science, and Cochrane Library. Ultimately, we identified 9 studies, involving 3 cohort studies and 6 cross-sectional studies. We used Hedges' g as the effect size, and all pooled analyses were performed using random-effects models.

RESULTS

ARHL patients had higher depressive symptom scores than non-ARHL older adults (g = 0.52). When divided into subgroups based on study type, a large effect size was demonstrated in the cross-sectional study group (g = 0.68) and was not statistically different in the cohort study group (g = 0.06). Meta-regression results showed that the effect size of depression in older adults with ARHL was significantly associated with the percentage of females (t = 5.97, p = 0.000) and not significantly associated with age (t = 0.94, p = 0.364).

CONCLUSIONS

Patients with ARHL are more likely to be depressed than older adults with normal hearing, and this relationship is influenced by the gender of the patients.

Correlation between pure tone audiometry at all frequencies and distortion product otoacoustic emission of patients with hidden hearing loss

To explore the correlation between pure tone audiometry at all frequencies and distortion product otoacoustic emission (DPOAE) of hidden hearing loss (HHL). The workers exposed to noise from a factory in Zhangjiakou (noise exposure group, n = 73) and normal young and middle-aged people recruited by society (control group, n = 77) from August 2021 to April 2022 were study subjects, and all of them underwent audiometry in clinic. Compared with the control group, the noise exposure group had significantly higher threshold by extended high-frequency audiometry at all frequencies and higher signal-to-noise ratio threshold (SNR50) (all P < 0.001), and higher amplitude ratio of SP to AP of the waveform induced by short sound at 96, 90, 80 and 70 dB nHL and lower SNR at 6 kHz and above (all P < 0.05).         The pure tone audiometry was correlated with DPOAE test results at the frequencies of 6, 8, 9 and 10 kHz (P < 0.001). The results of speech audiometry in noise were related to the average SNR of DPOAE test at each frequency (P = 0.026,r = -0.265). The ratio of SP to AP in electrocochleogram recorded at the intensity of 96 dB nHL was correlated with the average SNR at 6 kHz and above in DPOAE test (P = 0.018,r = -0.461), and with the average auditory threshold at each frequency in extended high-frequency audiometry (P = 0.032, r = 0.421). DPOAE has certain value in detecting HHL.

Hearing loss, social isolation and depression in participants aged 50 years or over in Tasmania, Australia

OBJECTIVE

Acquired hearing loss (HL) in adult life is one of the most prevalent health conditions and is associated with several chronic diseases. Hearing loss can lead to reduced social activity and individuals' perceptions of supportiveness within social networks. This study explored the effects of corrected vs. uncorrected hearing loss on social support, social isolation, anxiety and depression.

METHODS

We undertook a cross-sectional study. An online survey was completed by 7442 Australian residents aged 50 years or older as part of the Island Study Linking Ageing and Neurodegenerative Disease (ISLAND). Respondents were grouped into those with no reported acquired HL, those with corrected HL (managed with hearing aids and other listening devices) and those with uncorrected HL.

RESULTS

Hearing loss was reported by 1274 participants (17%). Compared to male participants, there was a higher proportion of female participants in the No-HL group (25% male, 75% female). Compared to participants with corrected or no-HL, those with HL (n = 548, 7%) reported significantly smaller (p = .007) and less supportive social networks (p = .001), higher self-reported anxiety (p < .001) and depression (p < .001) symptoms. Depression scores were significantly higher in those with HL-corrected than No-HL (SMD = .10, p = .04).

CONCLUSIONS

Uncorrected HL was associated with poor mental health and social isolation, compounding the risk of dementia. Correcting for HL appeared to mitigate these outcomes, except for depression. Longitudinal studies are needed to track the effects of HL correction over time. Hearing status needs to be assessed when people present with mental health concerns, so health professionals can make appropriate referrals and provide relevant advice and support.

Investigating the causal relationship between inflammation and multiple types of hearing loss: a multi-omics approach combining Mendelian randomization and molecular docking

Background

Hearing loss affects over 10% of the global population. Inflammation is a key factor in hearing loss caused by noise, infection, and aging, damaging various hearing-related tissues (e.g., spiral ligament, stria vascularis). Mendelian randomization (MR) can help identify potential causal relationships and therapeutic targets.

Methods

We conducted MR analyses on 91 inflammatory proteins (n = 14,824) and genome-wide association study results for various hearing loss types in European ancestry populations, including sensorineural hearing loss (SNHL; ncases = 15,952, ncontrols = 196,592), sudden idiopathic hearing loss (SIHL; ncases = 1,491, ncontrols = 196,592), and other hearing loss (OHL; ncases = 4,157, ncontrols = 196,592). Additionally, hearing loss with difficulty in hearing (ncases = 14,654, ncontrols = 474,839) served as a validation set. To predict inflammatory protein-enriched pathways and tissues, we performed enrichment analysis, functional annotation, and tissue analyses using "OmicsNet2.0" and "FUMA" platforms. We also combined "CoreMine" and molecular docking to explore potential drugs targeting inflammatory proteins and investigate binding efficacy.

Results

CCL19 was identified as a common risk factor for SNHL and OHL, which was validated in the hearing loss with difficulty in hearing dataset. Tissue analysis revealed that SIHL-related inflammatory proteins were enriched in the amygdala. Multi-omics research indicated associations between inflammatory proteins and neurodegenerative diseases. Molecular docking studies suggested that Chuanxiong Rhizoma and Uncariae Ramulus Cumuncis are potential drugs for targeting CCL19.

Conclusion

This study identified CCL19 as a common risk factor for various types of hearing loss through MR analysis, highlighting the crucial role of inflammatory proteins in hearing loss. The enrichment of related inflammatory proteins in the amygdala and their association with neurodegenerative diseases provide new insights into the mechanisms of hearing loss.

A comprehensive evaluation on the associations between hearing and vision impairments and risk of all-cause and cause-specific dementia: results from cohort study, meta-analysis and Mendelian randomization study

BACKGROUND

Epidemiological studies show inconsistent links between hearing/vision impairment and dementia risk. Using multisource data, we investigated how single or combined sensory impairments relate to risks of all-cause and specific types of dementia.

METHODS

We employed a triangulation approach combining three methodologies. We analyzed 90,893 UK Biobank (UKB) adults to explore single and joint effects of hearing and vision impairments on all-cause and Alzheimer's disease (AD), vascular dementia (VD) and non-AD non-VD (NAVD). A meta-analysis of prospective studies involving 937,908 participants provided stronger evidence. Finally, we conducted Mendelian randomization (MR) analysis using genome-wide association studies from UKB (361,194 participants) and FinnGen (412,181 participants) to validate relationships between sensory impairments and dementia occurrence.

RESULTS

In the UKB cohort study, compared to participants with normal hearing, those in the mild and severe hearing impairment groups had progressively and significantly higher risk of all-cause dementia (mild: HR1.52, 95%CI 1.31-1.77; severe: HR1.80, 95%CI 1.36-2.38), AD (mild: HR1.63, 95%CI 1.30-2.04; severe: HR2.18, 95%CI 1.45-3.27), VD (mild: HR1.68, 95%CI 1.19-2.37; severe: HR1.47, 95%CI 1.22-1.78), and NAVD (mild: HR1.47, 95%CI 1.22-1.78; severe: HR1.98, 95%CI 1.43-2.75). Besides, vision impairment was associated with an increased risk of all-cause dementia (HR1.55, 95%CI 1.18-2.04) and NAVD (HR1.51, 95%CI 1.07-2.13). Furthermore, dual sensory impairment was associated with stepwise increased risks of all-cause and cause-specific dementia than single hearing or vision impairment. In the meta-analysis of 31 prospective cohort studies, risks of all-cause dementia and AD were elevated in participants with single hearing impairment (all-cause dementia: HR1.30, 95%CI 1.21-1.40; AD: HR1.30, 95%CI 1.21-1.40) and dual sensory impairment (all-cause dementia: HR1.63, 95%CI1.14-2.12; AD: HR 2.55, 95%CI 1.19-3.91), while single vision impairment only associated with higher risk of all-cause dementia (HR1.43, 95%CI 1.16-1.71) but not AD. Finally, the MR analysis revealed a significant association between hearing impairment and all-cause dementia (OR1.74, 95%CI 1.01-2.99), AD (OR1.56, 95%CI 1.09-2.23), and NAVD (OR1.14, 1.02-1.26), as well as vision impairment and NAVD (OR1.62, 95%CI 1.13-2.33).

CONCLUSIONS

Our findings showed significant associations between hearing and vision impairments and increased risks of all-cause and cause-specific dementia. Standardized hearing and vision assessment and intervention should be emphasized in dementia prevention strategies.

Risk factors for mild cognitive impairment in patients with age-related hearing loss: a meta-analysis

OBJECTIVES

One of the most common sensory impairments in the elderly is age-related hearing loss, and individuals with this condition have a higher risk of mild cognitive impairment than the overall aged population. The purpose of this study was to conduct a systematic review of the literature in order to evaluate the evidence supporting the hypothesis that mild cognitive impairment may be developed in patients with age-related hearing loss.

METHODS

The PRISMA principles were followed when searching the databases of the China Knowledge Network, Wanfang, China Biomedical Literature Database, Pub Med, Cochrane Library, Embase, and Web of Science. Two investigators independently carried out the quality assessment, data extraction, and literature review of the eligible studies. Stata 17.0 was used to finish the statistical analysis and descriptive results.

RESULTS

A total of 13 articles containing 2,222,036 individuals who were evaluated for demographic traits, factors associated with age-related hearing loss, vascular neurologic factors, and psychological factors were included after 2166 search records were found in the database. In patients with age-related hearing loss, eleven factors were found to be risk factors for the development of mild cognitive impairment: age (OR = 1.63; 95% CI 1.09-2.43), male (OR = 1.29; 95% CI 1.14-1.47), degree of hearing loss (OR = 1.35; 95% CI 1.03-1.75), not wearing hearing aids (OR = 1.56; 95% CI 1.37-1.79), cerebrovascular disease (OR = 1.41; 95% CI 1.17-1.69), cardiovascular disease (OR = 1.29; 95% CI 1.07-1.55), diabetes mellitus (OR = 1.28; 95% CI 1.20-1.35), head injury (OR = 1.22; 95% CI 1.13-1.33), alcohol consumption (OR = 1.28; 95% CI 1.14-1.43), and tobacco use (OR = 1.19; 95% CI 1.14-1.25), and depression (OR = 1.63; 95% CI 1.47-1.81).

CONCLUSION

Caregivers can customize care strategies to decrease the occurrence of mild cognitive impairment in elderly deaf patients by considering demographic traits, factors associated with age-related hearing loss, vascular-neurologic factors, and psychological factors.

Self-reported hearing loss is associated with faster cognitive and functional decline but not diagnostic conversion in the ADNI cohort

INTRODUCTION

Hearing loss is identified as one of the largest modifiable risk factors for cognitive impairment and dementia. Studies evaluating this relationship have yielded mixed results.

METHODS

We investigated the longitudinal relationship between self-reported hearing loss and cognitive/functional performance in 695 cognitively normal (CN) and 941 participants with mild cognitive impairment (MCI) enrolled in the Alzheimer's Disease Neuroimaging Initiative.

RESULTS

Within CN participants with hearing loss, there was a significantly greater rate of cognitive decline per modified preclinical Alzheimer's cognitive composite. Within both CN and MCI participants with hearing loss, there was a significantly greater rate of functional decline per the functional activities questionnaire (FAQ). In CN and MCI participants, hearing loss did not significantly contribute to the risk of progression to a more impaired diagnosis.

DISCUSSION

These results confirm previous studies demonstrating a significant longitudinal association between self-reported hearing loss and cognition/function but do not demonstrate an increased risk of conversion to a more impaired diagnosis.

CLINICAL TRIAL REGISTRATION INFORMATION

NCT00106899 (ADNI: Alzheimer's Disease Neuroimaging Initiative, clinicaltrials.gov), NCT01078636 (ADNI-GO: Alzheimer's Disease Neuroimaging Initiative Grand Opportunity, clinicaltrials.gov), NCT01231971 (ADNI2: Alzheimer's Disease Neuroimaging Initiative 2, clinicaltrials.gov), NCT02854033 (ADNI3: Alzheimer's Disease Neuroimaging Initiative 3, clinicaltrials.gov).

HIGHLIGHTS

Hearing loss is a potential modifiable risk factor for dementia. We assessed the effect of self-reported hearing loss on cognition and function in the ADNI cohort. Hearing loss contributes to significantly faster cognitive and functional decline. Hearing loss was not associated with conversion to a more impaired diagnosis.

Association of Spouses' Sensory Loss with Depressive Symptoms, Self-Reported Health, and Functional Disability Among Middle-Aged and Older Adults in China: A Cross-Sectional Study

OBJECTIVE

To investigate cross-sectional associations between spouses' sensory loss and depressive symptoms, self-rated health, and functional disability.

METHODS

We included 10,410 individuals from the China Health and Retirement Longitudinal Study. We used the cross-sectional design and determined hearing loss, vision loss, and dual sensory loss by self-reports. We assessed depressive symptoms using the Center for Epidemiological Studies Depression Scale. We assessed self-reported health status using one item. Functional disability was defined as having difficulties in activities of daily living (ADL) and instrumental activities of daily living (IADL).

RESULTS

Individuals with spouses' dual sensory loss had a higher prevalence of depressive symptoms (45.19%), ADL (17.31%), and IADL impairments (21.97%) and a lower rate of self-rated good health (20.78%) than those with no or single loss. Spouse's sensory loss was associated with depressive symptoms, self-rated health, ADL, and IADL impairments (p < .05). Husbands' ADL impairments were associated with wives' vision loss (p < .05). Wives' IADL impairments were associated with husbands' hearing loss (p < .05).

CONCLUSIONS

Spouses' sensory loss was related to depressive symptoms, self-rated health, ADL, and IADL impairments. There was a gender specificity in the effect of spousal vision loss or hearing loss on ADL and IADL impairments.

Dual sensory impairments in companion dogs: Prevalence and relationship to cognitive impairment

PURPOSE

Many older dogs (Canis lupus familiaris) develop cognitive impairment. Dog owners often describe impairments in multiple sensory functions, yet the relationships between sensory and cognitive function in older dogs is not well understood.

METHODS

We performed assessments of dog vision and hearing, both clinically (n = 91, electroretinography and brainstem auditory evoked potential) and via validated questionnaire (n = 238). We determined prevalence of sole and dual hearing/vision impairments in younger (<8 years) and older (≥8 years) dogs. Impairment cutoffs were determined using data from young dogs. We assessed the relationships between questionnaire-assessed vision and/or hearing impairments and cognitive impairment using logistic regression.

RESULTS

Younger and older dog groups had similar distributions of sex and purebred/mixed breed status. Sex had no relationship to prevalence of sensory impairments. Older dogs had higher prevalence of hearing, vision, and dual sensory impairments, assessed both clinically and by questionnaire (P<0.001), and cognitive impairment assessed by questionnaire (P<0.001). Dogs had higher prevalence of reported cognitive impairment when owners reported dual vision and hearing impairments (79-94%, versus 25-27% in dogs with no sensory impairments), which was most consistent in dogs aged ≥8 years. In these older dogs, dual vision/hearing impairments were associated with a significantly increased risk of cognitive impairment (1.8-2.0 odds ratio).

CONCLUSION

Dogs aged ≥8 years are at higher risk for dual hearing/vision impairments and associated cognitive impairments. The causal relationship between these impairments is not defined, but clinical consideration of these multimorbidity risks should be made in older dogs.

Single cell RNA sequencing provides novel cellular transcriptional profiles and underlying pathogenesis of presbycusis

Age-related hearing loss (ARHL) or presbycusis is associated with irreversible progressive damage in the inner ear, where the sound is transduced into electrical signal; but the detailed mechanism remains unclear. Here, we sought to determine the potential molecular mechanism involved in the pathogeneses of ARHL with bioinformatics methods. A single-cell transcriptome sequencing study was performed on the cochlear samples from young and aged mice. Detection of identified cell type marker allowed us to screen 18 transcriptional clusters, including myeloid cells, epithelial cells, B cells, endothelial cells, fibroblasts, T cells, inner pillar cells, neurons, inner phalangeal cells, and red blood cells. Cell-cell communications were analyzed between young and aged cochlear tissue samples by using the latest integration algorithms Cellchat. A total of 56 differentially expressed genes were screened between the two groups. Functional enrichment analysis showed these genes were mainly involved in immune, oxidative stress, apoptosis, and metabolic processes. The expression levels of crucial genes in cochlear tissues were further verified by immunohistochemistry. Overall, this study provides new theoretical support for the development of clinical therapeutic drugs.

Voice Disorders and Hearing Loss May Be Additive Risk Factors for Depression in a National Cohort

OBJECTIVES

Hearing loss (HL) (receptive communication impairment) is a known risk factor for depression. However, dysphonia (expressive communication impairment), has received little study. We study HL, self-reported voice disorder, and combined impairment as risk factors for depression in a large national cohort.

METHODS

This was a cross-sectional epidemiologic study. Data were analyzed from the Korean National Health and Nutrition Examination Survey (KNHANES) cycles 2008-2012 and 2019-2020. KNHANES uniquely contains both audiometry and voice disorder data. HL (yes/no) was defined as ≥25 dB pure tone average. Voice disorder (yes/no) was defined by self-report. Depression (yes/no) was defined by physician diagnosis. Odds ratios for depression were calculated using multivariable logistic regressions with HL and voice disorder.

RESULTS

8,524 individuals aged 19 to 80 years old had complete data. The mean age was 57.3 years (SD = 13.4) and 64% were women. All regressions were controlled for age and sex. Those with HL, versus those without, had 1.27 times the odds (95% CI = 1.07-1.52, p = 0.007) of depression. Those with self-reported voice disorder, versus those without, had 1.48 times the odds (1.22-1.78, p < 0.001) of depression. Those with HL and self-reported voice disorder, versus those with neither, had 1.79 times the odds (1.27-2.48, p < 0.001) of depression.

CONCLUSIONS

This study demonstrates independent relationships between HL and depression and self-reported voice disorder and depression. Combined HL and self-reported voice disorder had nearly 1.8 times the odds of depression. This is likely due to the grossly additive effect of difficulty with incoming and outgoing communication streams.

LEVEL OF EVIDENCE

II Laryngoscope, 134:4060-4065, 2024.

Neurovascular coupling dysfunction associated with cognitive impairment in presbycusis

The neuropathological mechanism underlying presbycusis remains unclear. This study aimed to illustrate the mechanism of neurovascular coupling associated with cognitive impairment in patients with presbycusis. We assessed the coupling of cerebral blood perfusion with spontaneous neuronal activity by calculating the correlation coefficients between cerebral blood flow and blood oxygen level-dependent-derived quantitative maps (amplitude of low-frequency fluctuation, fractional amplitude of low-frequency fluctuation, regional homogeneity, degree centrality). Four neurovascular coupling metrics (cerebral blood flow-amplitude of low-frequency fluctuation, cerebral blood flow-fractional amplitude of low-frequency fluctuation, cerebral blood flow-regional homogeneity and cerebral blood flow-degree centrality) were compared at the global and regional levels between the presbycusis group and the healthy control group, and the intrinsic association between the altered neurovascular coupling metrics and the neuropsychological scale was further analysed in the presbycusis group. At the global level, neurovascular coupling was significantly lower in the presbycusis group than in the control group and partially related to cognitive level. At the regional level, neurovascular biomarkers were significantly elevated in three brain regions and significantly decreased in one brain region, all of which involved the Papez circuit. Regional neurovascular coupling provides more information than global neurovascular coupling, and neurovascular coupling dysfunction within the Papez circuit has been shown to reveal the causes of poor cognitive and emotional responses in age-related hearing loss patients.

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.

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.

Dynamic associations between vision and hearing impairment and depressive symptoms among older Chinese adults

BACKGROUND

Whether the impact of vision impairment (VI)/hearing impairment (HI) on depressive symptoms changes over time has not been investigated. This study aimed to examine the complex dynamic associations between VI/HI and depressive symptoms to design effective prevention strategies for older Chinese adults.

METHODS

Data were from the China Health and Retirement Longitudinal Study (CHARLS). The study identified self-reported VI, HI, depressive symptoms, and other covariates (including social isolation). Logistic regression models were used to analyze the dynamic associations across three waves, with the assessment of multiplicative and additive interactions.

RESULTS

Of the 8519 participants in wave 1 (mean [SD] age, 62.0 [8.0] years, 49.5 % male), 38.5 % had depressive symptoms. After adjusting for covariates including social isolation, VI and HI were significantly associated with depressive symptoms across all three waves. Specifically, the adjusted odds ratio (AOR) of VI increased from 2.08 (95 % CI: 1.89 to 2.29) in wave 1 to 2.15 (95 % CI: 1.90 to 2.44) in wave 3; while the AOR of HI increased from 1.80 (95 % CI: 1.58 to 2.04) in wave 1 to 2.11 (95 % CI: 1.75 to 2.51) in wave 3. The additive interactions between VI and HI on depressive symptoms in each wave (e.g., RERI [95 % CI]: 7.90 [2.51 to 12.30] in wave 1) were significant without adjusting for social isolation.

CONCLUSION

The study suggests that VI and HI are consistently associated with depressive symptoms among older adults in China over a four-year period, and their influences on mental health deserve more attention.

Social participation in older people with hearing impairment in Chinese community: A latent profile analysis

OBJECTIVES

Hearing impairment may lead to increased communication difficulties for older people, making their social participation less optimistic. However, there is little research on the social participation of older people with hearing impairment, especially based on the characteristics of their social participation. This study aimed to identify different social participation profiles in older people with hearing impairment and to explore sociodemographic characteristics, disease-related characteristics and psychosocial factors with different social participation profiles.

METHODS

A cross-sectional study of 300 older people with hearing impairment using the sociodemographic questionnaire, the Impact on Participation and Autonomy Questionnaire, the Lubben Social Network Scale-6, Medical Outcomes Study Social Support Survey and Geriatric Depression Scale-15 from May to August 2023 in a community of Beijing, China. Latent profile analysis was used to analyse the latent profiles of social participation in elderly with hearing impairment. Multiple logistic regression was used to explore the predictors of different profiles.

RESULTS

The social participation of older people with hearing impairment in the community can be classified into three potential profiles: Profile 1 - high social participation group (76.05 %), Profile 2 - moderate social participation group (17.34 %), Profile 3 - low social participation group (6.61 %). Age, types of chronic diseases, self-reported health, severity of hearing impairment, social network, social support and depression were predictors of different profiles.

CONCLUSIONS

Nurses should pay attention to the characteristics, depression, social network and support of older people with different hearing impairment to improve social participation in different profiles.

IMPLICATIONS AND RECOMMENDATIONS

This was the first study exploring latent profiles of social participation in older people with hearing impairment. Insights from this study are useful for gerontological nursing to distinguish different profiles and further identify the characteristics of different profiles in older people with hearing impairment by characterizing the level of social participation in the community and better implement interventions according to profiles.

Depression as a Risk Factor for Dementia: A Meta-Analysis

Dementia is a syndrome characterized by the deterioration of cognitive function beyond what is expected. The increased risk of developing this syndrome resulting from established modifiable risk factors, such as depressive episodes, is currently a subject of interest. The aim of this study was to review the scientific evidence that addresses the relationship between depression and dementia. A bibliographic search of the PubMed and PsycInfo databases for articles published over the past 20 years was conducted with the following medical subject heading terms: depression or depressive, dementia, and incidence or cohort studies. After articles meeting the inclusion criteria were selected, relevant moderating variables were grouped as sample characteristics, methodological characteristics, extrinsic characteristics, and outcome variables. The 26 selected studies resulted in a sample comprising 1,760,262 individuals. Statistical analysis revealed a pooled relative risk for the development of dementia of 1.82 (95% CI=1.62-2.06). The primary variables evaluated were the diagnostic methods for depression and dementia and the presence of depression. Other variables, such as mean age, methodological quality of each study, follow-up time, and publication year, were also evaluated. Age was statistically but not clinically significant. No relevant publication bias or alterations in the results were found when accounting for the quality of the studies. It is recommended that new moderating variables be evaluated or that existing variables be reformulated in future studies.

Dementia and Hearing Aid Use and Cessation: A National Study

PURPOSE

The current standard for management of hearing loss in the United States involves the use of a hearing aid. Anecdotal evidence suggests that the use of a hearing aid may be less effective in the context of dementia, though national data on use and cessation are not described.

METHOD

This longitudinal analysis of the National Health and Aging Trends Study followed participants who self-reported hearing aid use to estimate risk of hearing aid cessation over 9 years. We examine whether hearing aid cessation differs by dementia status using generalized estimating equations logistic regression accounting for loss to follow-up. Supplemental analyses were undertaken to examine the contribution of caregiving and environmental factors on hearing aid cessation.

RESULTS

Of 1,310 older adults who reported hearing loss (25% 80-84 years, 51% women, 74% White), 22% with dementia and 57% baseline hearing aid use. Dementia increased likelihood of ceasing hearing aid use during the first year after adoption (OR = 2.07, 95% CI [1.33, 3.23], p interaction = .11). In later years, older adults with either a previous or recent diagnosis of dementia had a 95% higher odds of hearing aid cessation (OR = 1.95, 95% CI [1.31, 2.90]), a decrease in odds with respect to the first year after adoption, when compared to participants without dementia, after adjusting for demographic, health, and economic factors. Economic and social factors that may influence care demands (more caregivers, income-to-poverty ratio, and additional insurance) increased likelihood for cessation for those with dementia.

CONCLUSIONS

Older adults with (vs. without) dementia are more likely to cease hearing aid use over time, most notably during the first year after adoption. Strategies to support hearing ability, such as self-management or care partner education, may improve communication for those living with co-occurring hearing loss and dementia.

Hearing loss, depression, and cognition in younger and older adult CI candidates

Background and Aim

Hearing loss in old age is associated with cognitive decline and with depression. Our study aimed to investigate the relationship between hearing loss, cognitive decline, and secondary depressive symptoms in a sample of younger and older cochlear implant candidates with profound to severe hearing loss.

Methods

This study is part of a larger cohort study designated to provide information on baseline data before CI. Sixty-one cochlear implant candidates with hearing loss from adulthood onwards (>18 years) were enrolled in this study. All had symmetrical sensorineural hearing loss in both ears (four-frequency hearing threshold difference of no more than 20 dB, PTA). Individuals with primary affective disorders, psychosis, below-average intelligence, poor German language skills, visual impairment, and a medical diagnosis with potential impact on cognition (e.g., neurodegenerative diseases,) were excluded. Four-frequency hearing thresholds (dB, PTA, better ear) were collected. Using the Abbreviated Profile of Hearing Aid Benefit, we assessed subjective hearing in noise. Clinical and subclinical depressive symptoms were assessed with the Beck Depression Inventory (BDI II). Cognitive status was assessed with a neurocognitive test battery.

Results

Our findings revealed a significant negative association between subjective hearing in noise (APHAB subscale "Background Noise") and BDII. However, we did not observe any link between hearing thresholds, depression, and cognition. Additionally, no differences emerged between younger (25-54 years) and older subjects (55-75 years). Unexpectedly, further unplanned analyses unveiled correlations between subjective hearing in quiet environments (APHAB) and cognitive performance [phonemic fluency (Regensburg Word Fluency), cognitive flexibility (TMTB), and nonverbal episodic memory (Nonverbal Learning Test), as well as subjective hearing of aversive/loud sounds (APHAB)], cognitive performance [semantic word fluency (RWT), and inhibition (Go/Nogo) and depression]. Duration of hearing loss and speech recognition at quiet (Freiburg Monosyllables) were not related to depression and cognitive performance.

Conclusion

Impact of hearing loss on mood and cognition appears to be independent, suggesting a relationship with distinct aspects of hearing loss. These results underscore the importance of considering not only conventional audiometric measures like hearing thresholds but also variables related to hearing abilities during verbal communication in everyday life, both in quiet and noisy settings.

Temporal associations between treated and untreated hearing loss and mild behavioral impairment in older adults without dementia

INTRODUCTION

Hearing loss (HL) and mild behavioral impairment (MBI) are non-cognitive markers of dementia. This study investigated the relationship between hearing and MBI and explored the influence of hearing aid use on the treatment of hearing loss, both cross-sectionally and longitudinally.

METHODS

Data were analyzed from National Alzheimer's Coordinating Center participants, age ≥50, dementia-free at baseline, collected between 2005 and 2022. Three self-report questions were used to generate a three-level categorical hearing variable: No-HL, Untreated-HL, and Treated-HL. MBI status was derived from the informant-rated Neuropsychiatric Inventory Questionnaire (NPI-Q) using a published algorithm. At baseline (n = 7080), logistic regression was used to examine the association between hearing status (predictor) and the presence of global and domain-specific MBI (outcome), adjusting for age, sex, cognitive diagnosis, and apolipoprotein E4 (APOE4). Cox proportional hazard models with time-dependent covariates were used to examine the effect of (1) hearing status as exposure on the rate of incident MBI (n = 5889); and (2) MBI as exposure on the rate of incident HL in those with no HL at baseline (n = 6252).

RESULTS

Cross-sectionally, participants with Untreated-HL were more likely to exhibit global MBI (adjusted odds ratio (aOR) = 1.66, 95% CI: 1.24-2.21) and individual MBI domains of social inappropriateness (aOR = 1.95, 95% CI: 1.06-3.39), affective dysregulation (aOR = 1.71, 95% CI: 1.21-2.38), and impulse dyscontrol (aOR = 1.71, 95% CI: 1.21-2.38), compared to those with No-HL. Participants with Treated-HL (i.e., hearing aid use) did not differ from No-HL for odds of global or most MBI domains, except for impulse dyscontrol (aOR = 1.38, 95% CI: 1.05-1.81). Longitudinally, we found relationships between Treated-HL and incident MBI (adjusted hazard ratio (aHR) = 1.29, 95% CI: 1.01-1.63) and between MBI and incident Untreated-HL (aHR = 1.51, 95% CI: 1.19-1.94).

DISCUSSION

Our cross-sectional results support that hearing aid use is associated with lower odds of concurrent global MBI in dementia-free participants. Longitudinally, relationships were found between MBI and HL. The severity of HL was not assessed, however, and may require further exploration.

Highlights

Hearing Loss (HL) and mild behavioral impairment (MBI) are markers of dementiaCross-sectionally: Untreated-HL was associated with global MBI burden, butHL treated with hearing aids was notWe found associations between MBI and incident Untreated-HL.

Protecting cognitive function in older adults with age-related hearing loss: Insights from The Irish Longitudinal Study on Ageing (TILDA) and the role of hearing aids

BACKGROUND

Age-related hearing loss (ARHL) is prevalent in adults over 70, impairing hearing sensitivity and speech perception. ARHL has been linked to an increased risk of cognitive decline and dementia. However, most affected adults are not receiving adequate treatment, including hearing aids.

OBJECTIVE

This study aimed to evaluate the impact of ARHL on cognitive decline in older adults participating in the Irish Longitudinal Study on Aging (TILDA).

DESIGN

METHODS: Data from four TILDA waves, a 6-year follow-up, was collected and analyzed using zero-inflated Poisson regression. The primary outcome, cognitive function, was assessed using Mini-Mental State Examination (MMSE) total score and error counts.

RESULTS

Our analysis revealed that age, education, use of aids to help with hearing, and history of stroke were significantly associated with error counts at baseline. Additionally, poor hearing was associated with a negative change in MMSE score from wave 4, indicating the potential role of ARHL in cognitive decline. When further adjusted for age, sex, history of stroke, hypertension, any emotional, nervous, or psychiatric problem, polypharmacy, and hearing aids, the zero-inflated Poisson model indicated that poor hearing, use of hearing aids, stroke, hypertension, and polypharmacy all predicted MMSE error counts in follow-up assessments. Moreover, the use of hearing aids was associated with a decreased likelihood of cognitive decline.

CONCLUSION

ARHL was independently associated with cognitive decline, underscoring the importance of addressing hearing loss in older adults. Future research should explore the potential of hearing aids to protect cognitive functioning in older adults.

The effect of hearing impairment and social participation on depressive symptoms in older adults: a cross-lagged analysis

Objective

This study aimed to investigate the relationship between hearing impairment, depressive symptoms, and social participation in older adults.

Methods

The study used data from the China Health and Retirement Longitudinal Study (CHARLS) in 2013 and 2018, which included 3,980 samples. The analysis was conducted using cross-lagged structural equation modeling with SPSS 23.0 and Mplus 7.4.

Results

The findings show that from 2013 to 2018, older people had significantly more hearing impairment and depressive symptoms and significantly less social participation. Hearing impairment was a significant negative predictor of social participation, and older adults with hearing impairment were less likely to participate in social activities. In addition, there may be a bidirectional relationship between hearing impairment and depressive symptoms, with both being positive predictors of each other. Finally, the study found that social participation played an important mediating role in the relationship between hearing impairment and depressive symptoms.

Conclusion

The study's findings highlight the complex interplay between hearing impairment, social participation, and depressive symptoms in older adults. Therefore, it is important to intervene promptly when hearing impairment is detected in the elderly; pay attention to patient guidance and comfort for the elderly with hearing impairment, give them positive psychological support, encourage them to get out of the house and participate in more social activities to avoid depressive symptoms. The study's results may inform the development of targeted interventions to address the mental health needs of older adults with hearing impairment.

Biological factors influencing depression in later life: role of aging processes and treatment implications

Late-life depression occurring in older adults is common, recurrent, and malignant. It is characterized by affective symptoms, but also cognitive decline, medical comorbidity, and physical disability. This behavioral and cognitive presentation results from altered function of discrete functional brain networks and circuits. A wide range of factors across the lifespan contributes to fragility and vulnerability of those networks to dysfunction. In many cases, these factors occur earlier in life and contribute to adolescent or earlier adulthood depressive episodes, where the onset was related to adverse childhood events, maladaptive personality traits, reproductive events, or other factors. Other individuals exhibit a later-life onset characterized by medical comorbidity, pro-inflammatory processes, cerebrovascular disease, or developing neurodegenerative processes. These later-life processes may not only lead to vulnerability to the affective symptoms, but also contribute to the comorbid cognitive and physical symptoms. Importantly, repeated depressive episodes themselves may accelerate the aging process by shifting allostatic processes to dysfunctional states and increasing allostatic load through the hypothalamic-pituitary-adrenal axis and inflammatory processes. Over time, this may accelerate the path of biological aging, leading to greater brain atrophy, cognitive decline, and the development of physical decline and frailty. It is unclear whether successful treatment of depression and avoidance of recurrent episodes would shift biological aging processes back towards a more normative trajectory. However, current antidepressant treatments exhibit good efficacy for older adults, including pharmacotherapy, neuromodulation, and psychotherapy, with recent work in these areas providing new guidance on optimal treatment approaches. Moreover, there is a host of nonpharmacological treatment approaches being examined that take advantage of resiliency factors and decrease vulnerability to depression. Thus, while late-life depression is a recurrent yet highly heterogeneous disorder, better phenotypic characterization provides opportunities to better utilize a range of nonspecific and targeted interventions that can promote recovery, resilience, and maintenance of remission.

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.

Investigation of the effect of age-related hearing loss on visual memory

Aim: To investigate the effect of age-related hearing loss on visual memory. Material and Method: 20 participants with normal hearing loss and 38 participants with hearing loss were included in the study. All of the patients were older than 65 years. Pure tone audiometry, speech audiometry and Benton visual retention test were applied to all participants. Results: Mean Benton test score of the hearing-normal and the hearing loss group were 13.10±1.48 and 8.81±3.27 respectively. Patients were divided into three groups as hearing-normal, hearing loss with WRS greater than 80% and hearing loss with WRS lower than 80%. In terms of Benton scores there was statistically significant difference between groups (p

Role of endocrine PACAP in age-related diseases

Pituitary adenylate cyclase activating polypeptide (PACAP) is a conserved neuropeptide, which confers diverse anti-aging endocrine and paracrine/autocrine effects, including anti-apoptotic, anti-inflammatory and antioxidant action. The results of the in vivo and in vitro experiments show that increasing emphasis is being placed on the diagnostic/prognostic biomarker potential of this neuropeptide in a wide array of age-related diseases. After the initial findings regarding the presence and alteration of PACAP in different body fluids in physiological processes, an increasing number of studies have focused on the changes of its levels in various pathological conditions associated with advanced aging. Until 2016 - when the results of previous human studies were reviewed - a vast majority of the studies had dealt with age-related neurological diseases, like cerebrovascular and neurodegenerative diseases, multiple sclerosis, as well as some other common diseases in elderly such as migraine, traumatic brain injury and post-traumatic stress disorder, chronic hepatitis and nephrotic syndrome. The aim of this review is to summarize the old and the new results and highlight those 'classical' and emerging clinical fields in which PACAP may become subject to further investigation as a diagnostic and/or prognostic biomarker in age-related diseases.

Hearing Health Outcomes as a Function of Age, Gender, and Diversity

The United States does not ensure equitable access to hearing health care for all age groups, largely because these services are costly and even unobtainable in some places. Barriers to care are discussed within a context of the social determinants of health, under-representativeness of hearing-care professionals from historically marginalized communities, older adults and age-related hearing loss, and associated health conditions. The MarkeTrak 2022 study generated a sample of 15,138 respondents with information on 43,597 individuals. Data analysis revealed that self-reported hearing difficulty appears to increase with age with a rate of 12.4% for adults 18 years of age and older. A substantial proportion of individuals with hearing difficulty assumed that their problem was age-related, followed by exposure to loud sound and noise. Individuals with hearing difficulty were nearly three to four times more likely to have tinnitus, cognitive problems, and issues with balance and falling than those with no hearing problems. Self-reported hearing difficulty was lower for historically marginalized groups (7%) than for the White population (12%). Recommendations are presented to reduce the burden of hearing difficulty and hearing aid deserts for rural and urban populations.

Hearing Aid Usage and Reported Hearing Difficulty in Americans With Subclinical Hearing Loss

OBJECTIVE

Subclinical hearing loss (SCHL) (previously defined by our group as a four-frequency pure tone average [PTA4] >0 to ≤25 dB) has recently been associated with depressive symptoms and cognitive decline. This suggests that the common 25 dB adult cutpoint in the United States for normal hearing may not be sensitive enough. We aim to characterize real-world hearing difficulties, as measured by hearing aid use and self-reported hearing difficulty, among individuals with SCHL.

STUDY DESIGN

Analysis of biennial cross-sectional epidemiologic survey (National Health and Nutrition Examination Survey, 1999-2012, 2015-2016).

SETTING

Community, multicentered, national.

SUBJECTS

Noninstitutionalized US citizens ≥12 years old, n = 19,246.

MEASURES

PTA4 (500, 1,000, 2,000, 4,000 Hz), high-frequency pure tone average (PTAhf) (6,000, 8,000 Hz), reported hearing aid use, subjective difficulty hearing.

RESULTS

There were 806,705 Americans with SCHL who wore hearing aids (or 0.35% of the 227,324,096 Americans with SCHL; 95% confidence interval = 0.23%-0.54%). Among those with SCHL, 14.6% (33.1 million Americans) perceived a little trouble hearing and 2.29% (5.21 million Americans) perceived moderate/a lot of trouble hearing. When restricted to the borderline subcategory (>20 to ≤25 dB), 42.43% (6.64 million Americans) had at least a little trouble hearing. Among those with SCHL who wore hearing aids, 81% had a PTAhf >25 dB.

CONCLUSION

Despite hearing loss traditionally being defined by PTA4 ≤ 25 dB in the United States, nearly 1 million adults and adolescents with SCHL wore hearing aids, and nearly half with borderline HL had subjective difficulty hearing. To better reflect real-world difficulties, stricter definitions of hearing loss should be explored, including a lower cutpoint for the PTA4 or by using the more sensitive PTAhf.

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.

The impact of age-related hearing loss on structural neuroanatomy: A meta-analysis

This meta-analysis investigated the association between age-related hearing loss and structural neuroanatomy, specifically changes to gray matter volume. Hearing loss is associated with increased risk of cognitive decline. Hence, understanding the effects of hearing loss in older age on brain health is essential. We reviewed studies which compared older participants with hearing loss (age-related hearing loss: ARHL) to older adults without clinical hearing loss (no-ARHL), on neuroanatomical outcomes, specifically gray matter (GM) volume as measured by magnetic resonance imaging. A total of five studies met the inclusion criteria, three of which were included in an analysis of whole-brain gray matter volume (ARHL group n = 113; no-ARHL group n = 138), and three were included in analyses of lobe-wise gray matter volume (ARHL group n = 139; no-ARHL group n = 162). Effect-size seed-based d mapping software was employed for whole-brain and lobe-wise analysis of gray matter volume. The analysis indicated there was no significant difference between adults with ARHL compared to those with no-ARHL in whole-brain gray matter volume. Due to lacking stereotactic coordinates, the level of gray matter in specific neuroanatomical locations could only be observed at lobe-level. These data indicate that adults with ARHL show increased gray matter atrophy in the temporal lobe only (not in occipital, parietal, or frontal), compared to adults with no-ARHL. The implications for theoretical frameworks of the hearing loss and cognitive decline relationship are discussed in relation to the results. This meta-analysis was pre-registered on PROSPERO (CRD42021265375). Systematic Review Registration: https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=265375, PROSPERO CRD42021265375.

Hearing loss and depressive symptoms in older Chinese: whether social isolation plays a role

Background

Existing evidence links hearing loss to depressive symptoms, with the extent of association and underlying mechanisms remaining inconclusive. We conducted a cross-sectional study to examine the association of hearing loss with depressive symptoms and explored whether social isolation mediated the association.

Methods

Eight thousand nine hundred sixty-two participants from Guangzhou Biobank Cohort Study were included. Data on self-reported hearing status, the 15-item Geriatric Depression Scale (GDS-15), social isolation and potential confounders were collected by face-to-face interview.

Results

The mean (standard deviation) age of participants was 60.2 (7.8) years. The prevalence of poor and fair hearing was 6.8% and 60.8%, respectively. After adjusting for age, sex, household income, education, occupation, smoking, alcohol use, self-rated health, comorbidities, compared with participants who had normal hearing, those with poor hearing (β = 0.74, 95% confidence interval (CI) 0.54, 0.94) and fair hearing (β = 0.59, 95% CI 0.48, 0.69) had higher scores of GDS-15. After similar adjustment, those with poor hearing (odds ratio (OR) = 2.13, 95% CI 1.65, 2.74) or fair hearing (OR = 1.68, 95% CI 1.43, 1.99) also showed higher odds of depressive symptoms. The association of poor and fair hearing with depressive symptoms attenuated slightly but not substantially after additionally adjusting for social isolation. In the mediation analysis, the adjusted proportion of the association mediated through social isolation was 9% (95% CI: 6%, 22%).

Conclusion

Poor hearing was associated with a higher risk of depressive symptoms, which was only partly mediated by social isolation. Further investigation of the underlying mechanisms is warranted.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-022-03311-0.

A precision medicine tool to understand who responds best to hearing aids in late-life depression

OBJECTIVES

Accumulating evidence suggests that hearing loss (HL) treatment may benefit depressive symptoms among older adults with Major Depressive Disorder (MDD), but the specific individual characteristics of those who stand to improve most are unknown.

METHODS

N = 37 patients ≥60 years with HL and MDD received either active or sham hearing aids in this 12-week double-blind randomized controlled trial. A combined moderator approach was utilized in the analysis in order to examine multiple different pretreatment individual characteristics to determine the specific qualities that predicted the best depressive symptom response to hearing aids. Pretreatment characteristics included: Hearing Handicap Inventory for the Elderly (HHIE-S), pure tone average (PTA), speech reception threshold (SRT), Short Physical Performance Battery (SPPB), cognition (Repeatable Battery for the Assessment of Neuropsychological Status).

RESULTS

The analysis revealed a combined moderator, predicting greater improvement with active versus sham hearing aids, that had a larger effect size than any individual moderator (combined effect size [ES] = 0.49 [95% CI: 0.36, 0.76]). Individuals with worse hearing-related disability (HHIE-S: individual ES = -0.16), speech recognition (SRT: individual ES = -0.14), physical performance (SPPB: individual ES = 0.41), and language functioning (individual ES = 0.19) but with relatively less severe audiometric thresholds (PTA: individual ES = 0.17) experienced greater depressive symptom improvement with active hearing aids.

CONCLUSIONS

Older adults with relatively worse HL-related, physical, and cognitive functioning may stand to benefit most from hearing aids. Given the large number of older adults experiencing HL and MDD, a non-invasive and scalable means of targeting those most likely to respond to interventions would be valuable.

Examining the Combined Estimated Effects of Hearing Loss and Depressive Symptoms on Risk of Cognitive Decline and Incident Dementia

OBJECTIVES

Late-life depression is a comorbidity that may co-occur in older adults with hearing loss-each has prevalent and independent modifiable risk factors for dementia.

METHODS

Using data from 1,820 Health, Aging and Body Composition study participants (74 ± 2.8 years, 38% Black race), we compared the hearing loss-dementia/cognitive decline relationship between those with normal hearing/mild hearing loss and those with moderate or greater hearing loss. Using linear mixed-effects and Cox proportional hazard models, we investigated if the associations between hearing loss and cognitive decline or dementia (Modified Mini-Mental State [3MS] Examination and Digit Symbol Substitution Test [DSST]) differed by the presence or absence of depressive symptoms. Depressive symptoms were defined as Center for Epidemiologic Study-Depression scale 10 ≥10 at one or more visits from Years 1-5. Algorithmic incident dementia was defined using medication use, hospitalizations, and cognitive test scores. Audiometric hearing loss was measured at Year 5 and categorized as normal/mild versus moderate or greater hearing loss.

RESULTS

Having both hearing loss and depressive symptoms (vs. having neither) was associated with faster rates of decline in 3MS Examination (β = -0.30; 95% confidence interval [CI]: -0.78, -0.19) and DSST (β = -0.35; 95% CI: -0.67, -0.03) over 10 years of follow-up. Having both hearing loss and depressive symptoms (vs. neither) was associated with increased risk (hazard ratio [HR]: 2.91; 95% CI: 1.59, 5.33 vs. HR: 1.54; 95% CI: 1.10, 2.15 hearing loss only and HR: 2.35; 95% CI: 1.56, 3.53 depressive symptoms only) of incident dementia in multivariable-adjusted Cox proportional hazards models.

DISCUSSION

Comorbid conditions among hearing-impaired older adults should be considered and may aid in dementia prevention and management strategies.

Hearing Rehabilitative Treatment for Older Adults With Comorbid Hearing Loss and Depression: Effects on Depressive Symptoms and Executive Function

OBJECTIVES

Recent research has revealed important neural and psychiatric consequences of hearing loss (HL) in older adults. This pilot study examined the neural effects of HL and the impact of hearing aids on neuropsychiatric outcomes in major depressive disorder (MDD).

DESIGN

Twelve-week, double-blind, randomized controlled trial.

PARTICIPANTS/INTERVENTION

N = 25 (≥60 years) with MDD and moderate-profound HL were randomized to receive hearing aids (100% gain targets) or sham hearing aids (flat 30 dB HL) in addition to psychiatric treatment-as-usual.

MEASUREMENTS

Depressive symptoms (Hamilton Rating Scale for Depression [HRSD]), executive functioning (NIH Toolbox Flanker), integrity of auditory brain areas (structural MRI, diffusion tensor imaging).

RESULTS

At baseline, worse speech discrimination was associated with auditory cortical thinning (Left anterior transverse temporal gyrus: r = 0.755, p = 0.012) and lower integrity of the superior longitudinal fasciculus (FA: Left r = 0.772, p = 0.025, Right r = 0.782, p = 0.022). After 12-weeks, hearing aids were effective at improving hearing functioning (Hearing Handicap for the Elderly: active -12.47 versus sham -4.19, t = -2.64, df = 18, p = 0.016) and immediate memory (active +14.9 versus sham +5.7, t = 2.28, df = 16, p = 0.037). Moderate improvement was observed for hearing aids on executive functioning but did not reach statistical significance (Flanker: active +4.8 versus sham -2.4, t = 1.95, df = 15, p = 0.071). No significant effect on depression was found (HRSD: active -5.50 versus sham -7.32, t = 0.75, df = 19, p = 0.46).

CONCLUSIONS

HL can affect brain regions important for auditory and cognitive processing, and hearing remediation may have beneficial effects on executive functioning in MDD. Future studies may evaluate whether impairment in cognitive control consequent to HL may be an important risk mechanism for MDD.

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

Objectives

To examine the longitudinal association between subclinical hearing loss (SCHL) and neurocognitive performance.

Design

Longitudinal analyses were conducted among 2,110 subjects who underwent audiometric testing in a US multi-centered epidemiologic cohort study. The primary exposure was better ear hearing (pure tone average). SCHL was defined as hearing ≤ 25 dB. The primary outcome was neurocognitive performance, measured by Digit Symbol Substitution Test (DSST), Modified Mini Mental State Examination (3MS), and CLOX1. Linear mixed models were performed to assess the longitudinal association between hearing and cognitive performance, adjusting for covariates. Models were fit among all individuals and among individuals with SCHL only.

Results

Among 2,110 participants, mean (SD) age was 73.5 (2.9) years; 52.3% were women. Mean (SD) better ear pure tone average was 30.0 (13.1) dB. Mean follow-up was 9.1 years (range 3–16). Among all participants, worse hearing was associated with significantly steeper cognitive decline measured by the DSST [0.054-point/year steeper decrease per 10 dB worse hearing, 95% confidence interval (CI): 0.026–0.082] and 3MS (0.044-point/year steeper decrease per 10 dB worse hearing, CI: 0.026–0.062), but not CLOX1. Among those with SCHL, worse hearing was associated with significantly steeper cognitive performance decline as measured by DSST (0.121-point/year steeper decrease per 10 dB worse hearing, CI: 0.013–0.228), but not CLOX1 or 3MS.

Conclusion

Among those with SCHL, worse hearing was associated with steeper cognitive performance declines over time as measured by DSST. The relationship between hearing loss and cognition may begin at earlier levels of hearing loss than previously recognized.

Speech-in-noise hearing impairment is associated with an increased risk of incident dementia in 82,039 UK Biobank participants

INTRODUCTION

Little is known about the association between speech-in-noise (SiN) hearing impairment and dementia.

METHODS

In 82,039 dementia-free participants aged ≥60 years were selected from the UK Biobank. Cox proportional-hazards models were used to investigate whether SiN hearing impairment is associated with an increased risk of incident dementia.

RESULTS

Over 11 years of follow-up (median = 10.1), 1285 participants developed dementia. Insufficient and poor SiN hearing were associated with a 61% (hazard ratio [HR] = 1.61, 95% confidence [CI] 1.41-1.84) and 91% (HR = 1.91, 95% CI 1.55-2.36) increased risk of developing dementia, respectively, compared to normal SiN hearing. The association remained similar when restricting to follow-up intervals of ≤3, >3 to  <6, >6 to <9, and >9 years. There was limited evidence for mediation through depressive symptoms and social isolation.

DISCUSSION

SiN hearing impairment is independently associated with incident dementia, providing further evidence for hearing impairment as a potential modifiable dementia risk factor.

The Relationship Between Hearing and Mild Behavioral Impairment and the Influence of Sex: A Study of Older Adults Without Dementia from the COMPASS-ND Study

Background

Hearing loss and mild behavioral impairment (MBI), both non-cognitive markers of dementia, can be early warning signs of incident cognitive decline.

Objective

We investigated the relationship between these markers and reported the influence of sex, using non-dementia participants (n = 219; 107 females) from the Canadian Comprehensive Assessment of Neurodegeneration and Dementia (COMPASS-ND).

Methods

Hearing was assessed with the 10-item Hearing Handicap for the Elderly-Screening (HHIE-S) questionnaire, a speech-in-noise test, screening audiometry, and hearing aid use. MBI symptoms were assessed using the Neuropsychiatric Inventory Questionnaire (NPI-Q). Multivariable linear regressions examined the association between hearing and MBI symptom severity and multiple logistic regressions examined the association between hearing and MBI domains.

Results

HHIE-S score was significantly associated with greater global MBI symptom burden, and symptoms in the apathy and affective dysregulation domains. Objective measures of audiometric hearing loss and speech-in-noise testing as well as hearing aid use were not associated with global MBI symptom severity or the presence of MBI domain-specific symptoms. Males were older, had more audiometric and speech-in-noise hearing loss, higher rates of hearing-aid use, and showed more MBI symptoms than females, especially apathy.

Conclusion

The HHIE-S, a subjective self-report measure that captures emotional and social aspects of hearing disability, was associated with informant-reported global MBI symptom burden, and more specifically the domains of affective dysregulation and apathy. These domains can be potential drivers of depression and social isolation. Hearing and behavior change can be assessed with non-invasive measures, adding value to a comprehensive dementia risk assessment.

Otolaryngic sensory loss as a measure of frailty among older US adults

BACKGROUND

Frailty is a syndrome characterized by reduced physiologic reserve and increased vulnerability to poor health outcomes. Disruption of sensorineural function appears to serve as a novel biomarker of frailty. Using population-level data, we sought to characterize the association between otolaryngic sensory dysfunction and frailty.

METHODS

A cross-sectional analysis of the 2011-2012 US National Health and Nutrition Examination Survey was performed on adults ≥40 years of age (n = 2138). Participants were grouped by subjective gustatory dysfunction (sGD), olfactory dysfunction (sOD), hearing loss (sHL), and measured hearing loss (mHL) with pure tone averages (PTAs). Frailty was operationalized using a continuous 36-item frailty index (FI) scored from 0 to 1, stratified in 4 categories ("non-frail," "vulnerable," "frail," or "most frail").

RESULTS

All sensory loss groups had significantly higher FI scores than those without sensory loss (sGD = 0.15; sOD = 0.14; sHL = 0.15; low-frequency mHL = 0.16; high-frequency mHL = 0.14 vs control = 0.11; p < 0.007 for all). "Vulnerable" individuals had increased odds of sOD (adjusted odds ratio [aOR], 1.45; 95% confidence interval [CI], 1.05-2.00), whereas "frail" individuals had increased odds of sOD (aOR, 1.85; 95% CI, 1.26-2.71) and low-frequency mHL (aOR, 4.01; 95% CI, 1.27-12.63). The "most frail" individuals had increased odds of sHL (aOR, 11.72; 95% CI, 2.88-47.66) and high-frequency mHL (aOR 5.10; 95% CI, 1.72-15.12). PTAs were linearly associated with FI (low: β = 10.15; 95% CI, 1.78-18.51; high: β = 19.85; 95% CI, 5.19-34.53).

CONCLUSION

Otolaryngic sensory loss is associated with increased frailty. Independent association of frailty with measures of olfaction and hearing suggests that olfactory and hearing assessments may help identify at-risk individuals with modifiable risk factors.

Age-Related Hearing Loss, Neuropsychological Performance, and Incident Dementia in Older Adults

BACKGROUND

Age-related hearing loss (HL) has been associated with dementia, though the neurocognitive profile of individuals with HL is poorly understood.

OBJECTIVE

To characterize the neurocognitive profile of HL.

METHODS

N = 8,529 participants from the National Alzheimer's Coordinating Center ≥60 years and free of cognitive impairment who were characterized as Untreated-, Treated-, or No HL. Outcomes included executive function (Trail Making Test [TMT] Part B), episodic memory (Immediate/Delayed Recall), language fluency (Vegetables, Boston Naming Test), and conversion to dementia. Regression models were fit to examine associations between HL and neurocognitive performance at baseline. Cox proportional hazards models examined the links between HL, neurocognitive scores, and development of dementia over follow-up.

RESULTS

At baseline, those with Untreated HL (versus No HL) had worse neurocognitive performance per standardized difference on executive function (TMT Part B [mean difference = 0.05 (95% CI 0.00, 0.10)]) and language fluency (Vegetables [mean difference = -0.07 (95% CI -0.14, -0.01)], Boston Naming Test [mean difference = -0.07 (95% CI -0.13, -0.01)]). No differences in these neurocognitive performance scores were demonstrated between Treated HL and No HL groups other than MMSE [mean difference = -0.06 (95% CI -0.12, 0.00)]. Through follow-up, executive dysfunction differed by hearing group (χ2(2) = 46.08, p < 0.0001) and was present among 39.12% in No HL, 44.85% in Untreated HL, and 49.40% in Treated HL. Worse performance across all cognitive domains predicted incident dementia.

CONCLUSION

The observed association between Untreated HL and lower cognitive ability that improved when hearing aids were worn may reflect an inability to hear the test instructions. Future studies using cognitive assessments validated for use in HL are needed to evaluate the neuropsychological profile of HL and identify individuals at risk for dementia.

Hearing Loss and Dementia: A Meta-Analysis of Prospective Cohort Studies

Background: Consensus is lacking with regard to whether hearing loss is an independent risk factor for dementia. We therefore conducted a meta-analysis to clarify the relationship of hearing loss and dementia.

Methods: Prospective cohort studies investigating the association between hearing loss and the incidence of dementia in a community-derived population were included by searching electronic databases that included PubMed, Embase, and Cochrane's Library. A random-effects model was adopted to combine the results.

Results: Fourteen cohorts including 726,900 participants were analyzed. It was shown that hearing loss was independently associated with dementia [adjusted hazard ratio (HR): 1.59, 95% confidence interval (CI): 1.37 to 1.86, p < 0.001; I² = 86%]. Sensitivity analysis sequentially excluding any of the individual studies included showed similar results. Subgroup analysis according to the diagnostic methods for hearing loss, validation strategy for dementia, follow-up duration, and adjustment of apolipoprotein E genotype also showed consistent results (p-values for subgroup differences all > 0.05). Meta-analysis with five studies showed that hearing loss was also connected to higher risk of Alzheimer's disease (adjusted HR: 2.24, 95% CI: 1.32 to 3.79, p = 0.003; I² = 2%).

Conclusions: Hearing loss may increase the risk of dementia in the adult population. Whether effective treatment for hearing loss could reduce the incidence of dementia should be explored in the future.

Neural circuits and behavioral pathways linking hearing loss to affective dysregulation in older adults

Substantial evidence now links age-related hearing loss to incident major depressive disorder in older adults. However, research examining the neural circuits and behavioral mechanisms by which age-related hearing loss leads to depression is at an early phase. It is known that hearing loss has adverse structural and functional brain consequences, is associated with reduced social engagement and loneliness, and often results in tinnitus, which can independently affect cognitive control and emotion processing circuits. While pathways leading from these sequelae of hearing loss to affective dysregulation and depression are intuitive to hypothesize, few studies have yet been designed to provide conclusive evidence for specific pathophysiological mechanisms. Here we review the neurobiological and behavioral consequences of age-related hearing loss, present a model linking them to increased risk for major depressive disorder and suggest how future studies may facilitate the development of rationally designed therapeutic interventions for older adults with impaired hearing to reduce risk for depression and/or ameliorate depressive symptoms.