Visual Impairment, Hearing Loss and Cognitive Function in an Older Population: Longitudinal Findings from the Blue Mountains Eye Study

Hearing loss and cognitive impairment among older adults: findings from the China health and retirement longitudinal study

BACKGROUND

With the rapid aging of populations, dementia has become a major health problem. Hearing loss is common among older adults and has been recognized as a contributing factor to cognitive impairment and dementia. We aimed to explore the association between hearing loss and cognitive impairment in older adults. We also sought to quantify the extent to which the impact of hearing loss on cognitive impairment could be mediated by depression and social isolation.

METHODS

We used nationally representative data from the China Health and Retirement Longitudinal Study (CHARLS), a population-based cohort study. The study population comprised adults aged 60 and older who participated in at least two waves of the CHARLS. Cognitive function was measured based on four dimensions: orientation, computation, memory, and drawing. Hearing loss was defined according to self-reported data. We used logistic regression models to analyze the cross-sectional association between hearing loss and cognitive impairment. Cox proportional hazards models were used to examine the longitudinal association between hearing loss and cognitive impairment. We also conducted an in-depth analysis of the severity of hearing loss and its associated risk of cognitive impairment. Additionally, we calculated the percentage of excess risk mediated (PERM) by depression and social isolation.

FINDINGS

In total, 7891 individuals were included in the cross-sectional analysis, and 5326 were included in the longitudinal analysis, with a mean follow-up of 6.38 years. In the cross-sectional analysis, hearing loss was associated with cognitive impairment after adjusting for all covariates (OR = 1.76, 95% CI: 1.49-2.08). In the longitudinal analysis, the hazard ratio for cognitive impairment with hearing loss compared with no hearing loss was 1.24 (95% CI: 1.06-1.46) after adjustment for demographics, socioeconomic factors, and health-related behaviors. Further analysis revealed that moderate or severe hearing loss had a strong relationship with cognitive impairment after adjusting for covariates (HR = 1.32, 95% CI: 1.07-1.62). Of the total association between hearing loss and cognitive impairment, 20.83% was mediated by depression and 4.17% by social isolation.

CONCLUSIONS

Hearing loss is independently associated with cognitive impairment, providing evidence that addressing hearing loss could help improve cognitive function.

The Associations of Sensory Impairment With 10-Year Risk of Dementia and Alzheimer's Disease: The Health and Retirement Study, 2010-2020

BACKGROUND

Studies have examined the association between dual sensory impairment and late-life cognitive outcomes in the U.S with inconsistent findings.

OBJECTIVE

To examine the associations between sensory impairment and 10-year risk of dementia or Alzheimer's disease among U.S. adults aged ≥ 50.

METHODS

A prospective cohort study based on the Health and Retirement Study from 2010 to 2020. Individuals aged ≥ 50 years without self-reported dementia and Alzheimer's disease in 2010 were included in the analysis. Self-reported visual and hearing impairments were measures in 2010. Main failure events included self-reported incident dementia and Alzheimer's disease over a 10-year follow-up period. Participants were categorized as having no visual or hearing impairment, visual impairment only, hearing impairment only, and dual sensory impairment. Fine-Gray competing risk regression model was applied to estimate the associations of sensory impairment with incident dementia and Alzheimer's disease, adjusted for demographic characteristics, health behaviors, and health conditions at baseline.

RESULTS

Of 20,248 identified individuals, 14.6% had visual impairment only, 11.2% had hearing impairment only, and 9.1% had dual impairment at baseline. After adjusting for all covariates, dual sensory impairment was associated with higher risk of dementia (HR = 1.46, 95% CI: 1.23-1.73) and Alzheimer's disease (HR = 1.35, 95% CI: 1.03-1.76). Visual impairment only was also associated with incident dementia and Alzheimer's disease among individuals <65 years.

CONCLUSION

Older adults in the U.S. with visual and hearing impairments simultaneously had a particularly greater risk of dementia and Alzheimer's disease, indicating the needs of targeted screening for timely treatment and further prevention of dementia and Alzheimer's disease.

Dual sensory loss and cognitive impairment: A study in elderly users of gerontological centers in a Galician urban area

SIGNIFICANCE

Several studies indicate that dual sensory loss (DSL) is related to cognitive impairment. However, there are still no conclusive data on the role of each individual deficit on cognitive performance when both co-occur in the same person.

PURPOSE

This study aimed to analyze the possible association between sensory deficit and cognitive impairment in a sample of older adults and whether this association differs in subjects with DSL compared with those with single or no sensory impairment.

METHODS

Participants of this study were older adult users of gerontological centers in an urban area of Galicia (Spain). All subjects underwent visual and auditory screening tests to detect the presence of DSL. The Spanish version of the Mini-Mental State Examination test was used to identify cognitive impairment. Hearing loss was defined according to Ventry and Weinstein's criteria. Visual impairment was defined as a binocular presenting visual acuity <0.5 (20/40). The presence of DSL was established on the basis of the definitions of the single deficits.

RESULTS

A total of 534 subjects were examined. Older adults with DSL had the worst results in the Mini-Mental test, and those without sensory impairment had the best. The likelihood of cognitive impairment was greater in older adults with DSL than in those without sensory impairment (odds ratio, 6.06 [3.14 to 11.65]). When only visual impairment was present, the likelihood of cognitive impairment was 3.73 times higher (0.95 to 3.09) than that of subjects with no sensory impairment. Hearing loss alone seems not to be significantly associated with a higher risk of cognitive impairment.

CONCLUSIONS

The results of this study highlight the importance of continuing research in DSL for the prevention of cognitive impairment, the design of intervention plans, and the optimization of health resources.

Dual sensory impairment: Global prevalence, future projections, and its association with cognitive decline

There is rising public health concern surrounding dual sensory impairment (DSI), or comorbid hearing and vision impairments. Its global prevalence and the magnitude of its association with cognitive decline (CD) is unclear. Three databases were searched for epidemiological studies examining DSI prevalence or its association with CD. Independent reviewers selected studies, extracted data, and evaluated bias. Random-effects meta-analyses were performed. Projections were estimated using United Nations data. The population attributable fraction of DSI-associated CD was calculated. Among 43 studies with 5,246,796 participants, clinically assessed DSI prevalence was 5.50% (95% confidence interval [CI] = 2.88%-10.26%), with regional/ethnic/age variations. DSI prevalence is projected to increase by 27.2% from 2025 to 2050. Approximately 59.83% (95%CI = 41.03-76.12) of DSI patients had cognitive impairment. Baseline DSI was associated with incident CD (odds ratio [OR] = 1.72, 95%CI = 1.37-2.15). Globally, 3.81% (95%CI = 1.05-10.55) of incident CD may be attributed to DSI. DSI is globally prevalent, growing, and associated with CD, highlighting the need for better health policy and resource allocation. HIGHLIGHTS: The global prevalence of DSI is 5.50%, with geographical, ethnical and age variations. The prevalence of DSI rises with age and is projected to increase by 27.2% by 2050. Approximately 60% of individuals with DSI may have measurable cognitive impairment. DSI was associated with a 72% greater longitudinal risk of incident CD. Globally, 3.81% of CD cases may be attributable to DSI.

A Prospective Association Between Sensory Impairment and Cognitive Performance Among Older Community-Dwelling Adults: The Role of Depressive Symptoms

We examined whether vision impairment (VI) and hearing impairment (HI) and dual sensory impairment (DSI) affect cognitive performance and whether depression mediates that effect. We examined 55,340 participants from the Survey of Health, Aging and Retirement in Europe, which assessed 32,325 participants in 2011 (baseline, Time 1), 2015 (follow-up, Time 2), sociodemographic data and health factors, self-reported VI, HI, and DSI at baseline, depression, and cognitive performance after four years. A multiple mediator model was tested using bootstrapping and resampling. At baseline, 22.9% had VI, 10.2% HI, and 10.4% had DSI. We found a significant negative association between VI (b = -0.023, p = .001) and DSI (b = -0.083, p = .001) and cognitive performance; both were also associated with depression, which was linked with poor cognition. VI or DSI among older adults are associated with poor cognitive function directly and indirectly by increasing depression symptoms.

Sensory impairments and depressive symptoms in Europe: a cross-national cohort study

OBJECTIVES

To investigate the associations between sensory impairments and the development of depressive symptoms across sex, age, and European regions, and to examine the mediating role of cognitive function, activities of daily living (ADL), and physical activity.

METHOD

A cohort study including 56,847 Europeans aged 50+ participating in at least two waves of the Survey of Health, Ageing and Retirement in Europe (SHARE). Associations were analyzed using mixed effects logistic regression models considering several confounders.

RESULTS

Overall, 17.8% developed depressive symptoms. Compared to participants with good vision and hearing, those with vision impairment (VI) (odds ratio (OR) = 1.35, 95% confidence interval (CI) 1.27-1.44), hearing impairment (HI) OR = 1.32, 95% CI 1.21-1.43, and dual sensory impairment (DSI, i.e. VI and HI) (OR = 1.93, 95% CI 1.75-2.13) had increased odds of depressive symptoms. The associations were consistent across sex and European regions but became stronger with advancing age among men. Dose-response relationships were found for all associations. Mediation analyses revealed that preventing cognitive decline, ADL limitations, and physical inactivity would eliminate 15.0%, 11.5%, and 21.4% of the total effect for VI, HI, and DSI, respectively.

CONCLUSION

Our findings emphasize the importance of preventing sensory impairments to avoid depressive symptoms.

Association of hearing, vision, and dual sensory impairment and risk of Alzheimer's disease: a nested case-control study

BACKGROUND

Hearing impairment is a known risk factor for Alzheimer's disease (AD), although less is known about vision impairment or dual sensory impairment (DSI) as risk factors for AD. We studied the association between diagnosed hearing impairment, visual impairment, or DSI, and the risk of AD.

METHOD

The Medication use and Alzheimer's disease study (MEDALZ) is a register-based nested case-control study including 70,718 community-dwelling persons diagnosed with incident AD in 2005-2011 in Finland and their 282,845 matched controls. Sensory impairment diagnoses (limited to those that cause irreversible sensory loss designated by medical specialists) at least five years prior to AD diagnosis (or matching date) were obtained from national healthcare registers, including specialized outpatient visits. Associations were studied with cofounder-adjusted conditional logistic regression.

RESULTS

Hearing impairment was associated with an increased risk of AD compared to people without a diagnosed sensory impairment (adjusted odds ratio (aOR) 1.15, 95% confidence interval (CI) 1.11-1.19), while no association was found in people with visual (aOR 1.02, 95% CI 0.99-1.05) or dual sensory impairment (aOR 1.05 (95% CI 0.95-1.15).

CONCLUSIONS

Hearing impairment can be a modifiable risk factor for AD, and thus its treatment in the aging population is important. Although we did not observe an association between visual impairment and AD, all sensory impairments decrease functioning and quality of life among older adults. Therefore, they should be treated, also among persons with cognitive decline or cognitive disorder.

CLINICAL TRIAL NUMBER

Not Applicable.

Multimorbidity Patterns, Leisure Activities, and Cognitive Function: A Population-Based Longitudinal Study

BACKGROUND

There is limited knowledge about the effect of leisure activities on cognitive decline related to different multimorbidity patterns. The study aimed to examine the role of leisure activities in the association between multimorbidity patterns and cognitive function.

METHODS

We conducted a community-based cohort study based on the 2002-2018 Chinese Longitudinal Health Longevity Survey. Multimorbidity patterns were examined by exploratory factor analysis. Multivariable linear and logistic regression models were used to assess the associations between multimorbidity, leisure activities, and cognitive function.

RESULTS

The study included 14 093 older adults. Those with specific multimorbidity patterns had lower Mini-Mental State Examination (MMSE) scores. Compared with individuals with cardiometabolic and sensory patterns who frequently engaged in activities such as housework, garden work, and watching TV/listening to the radio, those who participated in these activities less regularly had lower MMSE scores. Furthermore, a higher frequency change of participation and a greater variety of leisure activities were associated with better cognitive function.

CONCLUSIONS

The older individuals with multimorbidity are associated with lower MMSE scores, while those who participated in more leisure activities had higher cognitive function. Diverse and frequent leisure activities may help delay cognitive decline in Chinese older adults with different multimorbidities.

Sensory impairments associated with cognitive impairment among older adults in China: A community-based, 10-year prospective cohort study

Background

To address an existing gap in knowledge due to limited and inconclusive evidence, we aimed to investigate the association between sensory impairments and cognitive decline among older Chinese individuals.

Methods

We retrieved data on 6862 adults aged ≥65 years that were collected through the Chinese Longitudinal Healthy Longevity Study (CLHLS), a nationwide, prospective, community-based elderly cohort study. Visual or hearing impairment in the CLHLS were identified through self-reported questionnaire. Sensory impairments were categorised as no sensory impairment, hearing impairment only, visual impairment only, and dual sensory impairment according to hearing and vision function. Cognitive impairment was defined as having a score <18 on the Chinese version of the Mini Mental State Examination. We used a Cox proportional hazard model to evaluate the relationship between sensory and cognitive impairments.

Results

Among 6862 participants, 5.7% had dual sensory impairment, 7.4% had hearing impairment only, and had 17.2% visual impairment only. Compared with participants with no sensory impairment, those with hearing impairment only (adjusted hazard ratio (aHR) = 1.65; 95% confidence interval (CI) = 1.41, 1.92), visual impairment only (aHR = 1.25; 95% CI = 1.11, 1.41), and dual sensory impairment (aHR = 1.47; 95% CI = 1.25, 1.74) were significantly associated with higher risk of cognitive impairment in the fully adjusted model.

Conclusions

Our results show that having hearing impairment only, visual impairment only, and dual sensory impairment was significantly associated with a higher risk of cognitive impairment among Chinese older adults aged ≥65 years. This suggest a need for the timely identification and management of sensory impairments for the elderly to reduce dementia risk.

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

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

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.

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.

Sensory Loss and Risk of Dementia

Sensory loss in olfaction, vision, and hearing is a risk factor for dementia, but the reasons for this are unclear. This review presents the neurobiological evidence linking each sensory modality to specific dementias and explores the potential mechanisms underlying this. Olfactory deficits can be linked to direct neuropathologic changes in the olfactory system due to Alzheimer disease and Parkinson disease, and may be a marker of disease severity. Visual deficits potentially increase dementia risk in a vulnerable individual by reducing resilience to dementia. Hearing deficits may indicate a susceptibility to Alzheimer disease through a variety of mechanisms. More generally, sensory impairment could be related to factors associated with resilience against dementia. Further research is needed to tease out the specific and synergistic effects of sensory impairment. Studying sensory loss in relation to neurodegenerative biomarkers is necessary to clarify the mechanisms involved. This could produce new monitoring and management strategies for people at risk of dementia.

Hearing and vision impairment and social isolation over 8 years in community-dwelling older adults

BACKGROUND

Little is known about the long-term impact of hearing and vision impairment on social isolation. This study quantifies the association between hearing, vision, and concurrent hearing and vision impairment (dual sensory impairment) and social isolation over 8 years among older adults.

METHODS

Data were from the National Health and Aging Trends Study (NHATS), a cohort study (2011 - 2019) of U.S. Medicare beneficiaries aged 65 years and older. Social isolation was measured by a binary indicator incorporating four domains: living arrangement, core discussion network size, religious attendance, and social participation. Hearing, vision, and dual sensory impairments were measured by self-report and modeled categorically (no impairment [ref.], hearing impairment only, vision impairment only, dual sensory impairment). Associations between sensory impairments and odds of social isolation over 8 years were assessed using multivariate generalized logistic mixed models and adjusted for demographic and health characteristics.

RESULTS

Among 5,552 participants, 18.9% self-reported hearing impairment, 4.8% self-reported vision impairment, and 2.3% self-reported dual sensory impairment. Over 8 years, hearing impairment only was associated with 28% greater odds of social isolation. Participants with hearing impairment only were more likely to live alone and have limited social participation.

CONCLUSION

Greater clinical awareness of hearing impairment as a risk factor for social isolation can increase opportunities to identify and aid older adults who may benefit from resources and interventions to increase social connection and mitigate social isolation.

Strategies used during the cognitive evaluation of older adults with dual sensory impairment: a scoping review

BACKGROUND

Dual sensory impairment (DSI), the combination of visual and hearing impairments, is associated with increased risk for age-related cognitive decline and dementia. Administering cognitive tests to individuals with sensory impairment is challenging because most cognitive measures require sufficient hearing and vision. Considering sensory limitations during cognitive test administration is necessary so that the effects of sensory and cognitive abilities on test performance can be differentiated and the validity of test results optimized.

OBJECTIVE

To review empirical strategies that researchers have employed to accommodate DSI during cognitive testing of older adults.

METHODS

Seven databases (MEDLINE, Embase, Web of Science, CINAHL, PsycINFO, Global Health and the Evidence-Based Medicine Reviews databases) were searched for relevant articles integrating the three concepts of cognitive evaluation, aging, and DSI. Given the inclusion criteria, this scoping review included a total of 67 papers.

RESULTS

Twenty-eight studies reported five categories of strategies for cognitive testing of older adult participants with DSI: the assistance of experts, the modification of standardized test scoring procedures, the use of communication strategies, environmental modifications, and the use of cognitive tests without visual and/or auditory items.

CONCLUSIONS

The most used strategy reported in the included studies was drawing on the assistance of team members from related fields during the administration and interpretation of cognitive screening measures. Alternative strategies were rarely employed. Future research is needed to explore the knowledge-to-practice gap between research and current clinical practice, and to develop standardized testing strategies.

Umbrella review and Delphi study on modifiable factors for dementia risk reduction

A 2013 systematic review and Delphi consensus study identified 12 modifiable risk and protective factors for dementia, which were subsequently merged into the "LIfestyle for BRAin health" (LIBRA) score. We systematically evaluated whether LIBRA requires revision based on new evidence. To identify modifiable risk and protective factors suitable for dementia risk reduction, we combined an umbrella review of systematic reviews and meta-analyses with a two-round Delphi consensus study. The review of 608 unique primary studies and opinions of 18 experts prioritized six modifiable factors: hearing impairment, social contact, sleep, life course inequalities, atrial fibrillation, and psychological stress. Based on expert ranking, hearing impairment, social contact, and sleep were considered the most suitable candidates for inclusion in updated dementia risk scores. As such, the current study shows that dementia risk scores need systematic updates based on emerging evidence. Future studies will validate the updated LIBRA score in different cohorts. HIGHLIGHTS: An umbrella review was combined with opinions of 18 dementia experts. Various candidate targets for dementia risk reduction were identified. Experts prioritized hearing impairment, social contact, and sleep. Re-assessment of dementia risk scores is encouraged. Future work should evaluate the predictive validity of updated risk scores.

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.

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.

Sex differences in vision and hearing impairments across age and European regions : Findings from SHARE

AIM

Although sensory impairments are common conditions among older people, research often fails to consider the role of sex. We examined sex differences in vision impairment and hearing impairment across age and European regions.

METHODS

We conducted a cross-sectional study based on a pooled sample of 65,656 females and 54,881 males aged 50 years and older participating in the Survey of Health, Ageing and Retirement in Europe (SHARE) from 2004-2020. Logistic regression models with robust standard errors providing odds ratios (OR) and 95% confidence intervals (CI) were used to examine associations.

RESULTS

European females had generally higher odds of vision impairment (OR 1.16, 95% CI 1.12-1.21) but lower odds of hearing impairment than European males (OR 0.70, 95% CI 0.67-0.73). The female disadvantage in vision increased with advancing age, whereas the female advantage in hearing decreased. No overall sex difference in vision was found in northern Europe, but females had more vision impairments than males in southern (OR 1.23, 95% CI 1.14-1.32), western (OR 1.14, 95% CI 1.08-1.21) and eastern (OR 1.10, 95% CI 1.02-1.20) Europe. Females were healthier than males in terms of hearing in all regions, with the largest female advantage in northern Europe (OR 0.58, 95% CI 0.53-0.64).

CONCLUSION

Our findings demonstrate an overall consistent pattern of sex differences in sensory impairments across Europe showing an increasing female disadvantage in vision and a decreasing female advantage in hearing with advancing age.

Impact of hearing loss on cognitive function in community-dwelling older adults: serial mediation of self-rated health and depressive anxiety symptoms

Background

Hearing loss can exacerbate cognitive decline; therefore, exploring the mechanisms through which hearing loss affects cognitive function is crucial. The current study aimed to investigate the impact of hearing loss on cognitive function and the mediating role played by self-rated health and depressive anxiety symptoms.

Methods

Using stratified whole-group random sampling, the study employed a cross-sectional design and included 624 participants aged ≥65 years from three communities in Urumqi, China. Cognitive function was assessed using the Mini-Mental State Examination. Hearing function and self-rated health were determined by self-report. The 15-item Geriatric Depression Scale and the 7-item Generalized Anxiety Disorder Scale were used to assess depressive anxiety symptoms. Serial mediation analysis was performed using AMOS 26.0.

Results

Hearing loss can not only negatively affect cognitive function in older adults directly (direct effect = -0.106; SE = 0.045; 95% confidence interval (CI): -0.201 to -0.016), but also indirectly affect the relationship between hearing loss and cognitive function through self-rated health and depressive anxiety symptoms. The results of the serial mediation analysis showed that the total indirect effect of self-rated health and depressive anxiety symptoms was -0.115 (95% CI: -0.168 to -0.070), and the total effect of the model was -0.221 (95% CI: -0.307 to -0.132), with the total indirect effect accounting for 52.04% of the total effect of the model.

Conclusion

Our study discovered that there is a partial mediation of the relationship between hearing loss and cognitive function by self-rated health and depressive anxiety symptoms. It is suggested that by enhancing self-rated health and ensuring good mental health, the decline in cognitive function among older adults with hearing loss can be delayed.

Visual impairment as a risk factor of cognitive function impairment A six-year cohort study

PURPOSE

To explore whether baseline visual impairment (VI) increases the risk of cognitive function impairment (CFI).

METHODS

We conducted a population-based cohort study, with a six-year follow-up period. The exposure factor of interest in this study was VI. The Mini-Mental State Examination (MMSE) was used to assess participants' cognitive function. The Logistic regression model was used to investigate whether baseline VI had an effect on CFI. Confounding factors were adjusted in the regression model. The odds ratio (OR) and 95% confidence interval (CI) were used to quantify the effect of VI on CFI.

RESULTS

A total of 3297 participants were included in the present study. The mean age of included participants was 58.5 ± 7.2 years. Male accounted for 1480 (44.9%) of all participants. At baseline, 127 (3.9%) of the participants had VI. The MMSE score of participants who had VI at baseline decreased by 1.7 ± 3.3 points on average during the six-year follow-up, and that of participants who had no VI at baseline decreased by 1.1 ± 3.3 points on average. The difference was significant (t = 2.03, p = 0.040). Results of the multivariable Logistic regression model showed that VI was a risk factor for CFI, with an OR of 1.052 (95%CI: 1.014 to 1.092, p = 0.017).

CONCLUSIONS

Averagely, participants with VI experienced a decline in cognitive function 0.1 points faster per year than participants without VI, as measured by MMSE score. VI is an independent risk factor for CFI.

Association Between Sensory Impairment and Dementia: The Roles of Social Network and Leisure Activity

BACKGROUND

Evidence suggests that sensory impairment is linked to dementia; however, the role of social network and leisure activity in this relationship is unclear.

OBJECTIVE

Examine the association of hearing and visual impairment with dementia, and whether a rich social network and leisure activity moderates this association.

METHODS

Dementia-free older adults from the Swedish National Study on Aging and Care in Kungsholmen (n = 2,579) were followed up for up for a median of 10 years (interquartile range = 6). Visual impairment was assessed with a reading acuity test, and hearing impairment was ascertained via self-report and medical records. Dementia was diagnosed following international criteria. Data on social network and leisure activity was collected via self-report. Hazard ratios (HRs) of dementia risk were derived from Cox regression models.

RESULTS

Dual impairment, but not single impairment in hearing and vision was associated with a higher risk of dementia (HR: 1.62, 95% CI: 1.16 to 2.27). Compared to participants with no sensory impairment and a moderate-to-rich social network, those with dual impairment and low social network or leisure activity had higher dementia risk (HR: 2.08, 95% CI: 1.43 to 3.22; HR: 2.08, 95% CI: 1.43 to 3.22, respectively), whereas participants with dual impairment with a moderate-to-rich social network or leisure activity did not have significantly higher dementia risk (HR; 1.42, 95% CI: 0.87 to 2.33; HR; 1.42, 95% CI: 0.87 to 2.33, respectively).

CONCLUSION

A richer social network and participation in stimulating activities may mitigate the higher dementia risk in older adults with dual impairment in vision and hearing.

Concurrent hearing and vision impairment and 8-year memory decline in community-dwelling older adults

BACKGROUND

Hearing and vision impairments are risk factors for cognitive decline; less is known about dual sensory impairment. This study quantifies the association between dual sensory impairment and 8-year change in memory among older adults.

METHODS

Data (N = 5552) were from the National Health and Aging Trends Study. Memory (immediate/delayed word recall, subjective memory) was measured annually (2011 to 2019). Hearing and vision impairments were measured by self-report. Association between dual sensory impairment and 8-year change in memory was assessed using multivariate linear mixed effect models and generalized logistic mixed models.

RESULTS

Rate of memory decline was most accelerated among participants with dual sensory impairment. For example, 8-year decline in delayed word recall was -1.03 (95% confidene interval: -1.29, -0.77) for dual sensory impairment versus -0.79 (-0.92, -0.67) for single and -0.56 (-0.63, -0.48) for no impairment.

CONCLUSION

Older adults with dual sensory impairment may be at particularly higher risk for cognitive decline.

Gender differences in the association between sensory function and CIND among Chinese elderly: Based on CLHLS

OBJECTIVE

To explore the gender differences of the association between sensory impairment (SI) and the risk of cognitive decline and possible cognitive impairment, no dementia (CIND).

METHOD

Data were drawn from three waves of the nationally representative survey of China Longitudinal Healthy Longevity Survey (CLHLS) between 2011/12-2018 surveys, involving 6138 participants aged 65 or older who had no CIND at the baseline. Multivariate linear or logistic regression models were employed to examine the effect of SI on cognitive decline and CIND risk by gender stratification, respectively.

RESULTS

Hearing impairment and visual impairment were associated with lower MMSE scores, and the strength of the association was stronger in men than in women. Hearing impairment was related to an elevated risk of CIND both in men and women (Men: OR=2.46; 95% CI=1.81, 3.35; Women: OR=1.43; 95% CI=1.09, 1.88). However, the effect of visual impairment on CIND was statistically significant only in men (OR=1.43; 95% CI=1.09, 1.88). The risk of cognitive decline and CIND were significantly higher with single and dual SI than those without SI, except for women with single visual impairment.

CONCLUSION

SI is independently associated with cognitive decline and CIND risk, and the association differed by gender. Further researches should clarify the mechanism between SI and cognitive function among older adults, especially for gender differences.

Vision impairment, hearing impairment and functional Limitations of subjective cognitive decline: a population-based study

BACKGROUND

The association between sensory impairment including vision impairment (VI), hearing impairment (HI), dual impairment (DI) and the functional limitations of SCD (SCD-related FL) are still unclear in middle-aged and older people.

METHODS

162,083 participants from BRFSS in 2019 to 2020 was used in this cross-sectional study. After adjusting the weights, multiple logistic regression was used to study the relationship between sensory impairment and SCD or SCD-related FL. In addition, we performed subgroup analysis on the basis of interaction between sensory impairment and covariates.

RESULTS

Participants who reported sensory impairment were more likely to report SCD or SCD-related FL compared to those without sensory impairment (p < 0.001). The association between dual impairment and SCD-related FL was the strongest, the adjusted odds ratios (aORs) and 95% confidence interval (95% CI) were [HI, 2.88 (2.41, 3.43); VI, 3.15(2.61, 3.81); DI, 6.78(5.43, 8.47)] respectively. In addition, subgroup analysis showed that men with sensory impairment were more likely to report SCD-related FL than women, the aORs and 95% CI were [HI, 3.15(2.48, 3.99) vs2.69(2.09, 3.46); VI,3.67(2.79, 4.83) vs. 2.86(2.22, 3.70); DI, 9.07(6.67, 12.35) vs. 5.03(3.72, 6.81)] respectively. The subject of married with dual impairment had a stronger association with SCD-related FL than unmarried subjects the aOR and 95% CI was [9.58(6.69, 13.71) vs. 5.33(4.14, 6.87)].

CONCLUSIONS

Sensory impairment was strongly associated with SCD and SCD-related FL. Individuals with dual impairment had the greatest possibility to reported SCD-related FL, and the association was stronger for men or married subjects than other subjects.

The association between vision impairment and cognitive outcomes in older adults: a systematic review and meta-analysis

OBJECTIVES

To provide a quantitative synthesis of studies on the relationship between vision impairment (VI) and cognitive outcomes in older adults.

METHOD

A systematic search was undertaken of relevant databases for original articles published before April 2020. Random effect models were used to obtain pooled estimates of the associations between VI and cognitive outcomes (cognitive impairment and dementia) with subgroup analyses of VI measures, cross-sectional associations of VI with cognitive impairment, and longitudinal associations of baseline VI with incident cognitive impairment and dementia. Potential sources of heterogeneity were explored by meta-regression. Publication bias was evaluated with Egger's test.

RESULTS

Sixteen studies including 76,373 participants were included in this meta-analysis, with five cross-sectional studies and eleven longitudinal studies. There was a significantly increased risk of cognitive outcomes with VI identified by subjective measures (odds ratio (OR)=1.63; 95% confidence interval (CI): 1.26-1.99) and objective measures (OR = 1.59; 95% CI: 1.40-1.78). The odds of baseline cognitive impairment were 137% higher in older adults with VI compared with those without VI (OR = 2.37, 95% CI: 1.84-3.03) at baseline. Compared with older adults without VI at baseline, those with baseline VI had a higher relative risk (RR) of incident cognitive impairment (RR = 1.41; 95% CI: 1.31-1.51) and dementia (RR = 1.44, 95% CI: 1.19-1.75).

CONCLUSIONS

VI was associated with increased risks of cognitive impairment and dementia across cross-sectional and longitudinal studies. Additional research and randomized clinical trials are warranted to examine the implications of treatment for VI, such as wearing glasses and cataract surgery, to avoid cognitive impairment and dementia.

Do Sensory Impairments Portend Cognitive Decline in Older Chinese Adults? Longitudinal Evidence from a Nationally Representative Survey, 2011-2018

Previous studies on longitudinal sensory-cognition association are limited and have yielded inconsistent conclusions in western and developed countries. The present study obtained data from the China Health and Retirement Longitudinal Survey (CHARLS, 2011−2018) and aimed to investigate the longitudinal effects of sensory impairments including single vision impairment (SVI), single hearing impairment (SHI), and dual sensory impairment (DSI) on cognitive decline in middle-aged and older Chinese population. In total, 11,122 participants accomplished all 4 interviews over 8 years and were included. Cognitive performances were assessed using Mini-Mental Status Examination (MMSE) and self-reported sensory status were accepted as well. Confounding variables included age, sex, educational level, marital status, medical, and lifestyle related information. The impact of sensory impairment on cognitive decline over time was assessed using linear mixed-effects models (LMM). After being adjusted for multiple confounders, SVI/SHI/DSI were all shown to be significantly associated with executive functions, episodic memory impairment, and global cognitive decline over 8 years (all p < 0.05). Such associations become less significant among female and relatively younger populations (45−59 years old). Single vision and hearing impairments, along with dual sensory impairment, are all independently associated with subsequent cognitive decline among middle-aged and older Chinese populations over 8 years of longitudinal observation.

The Early Stage of Abnormal Aging: Cognitive Impairment

Cognitive impairment has become an important aspect affecting the health and quality of life of middle-aged and elderly people, which is defined as the difficulty of thought processing and leads to memory loss, difficulties making decisions, the inability to concentrate, and difficulties learning. The process of cognitive ability decline with age goes through subjective cognitive impairment (SCI) to mild cognitive impairment (MCI). There is abundant evidence supporting the link between cognitive impairment and several modifiable risk factors, such as physical activity, social activity, mental activity, higher education, and management of cardiovascular risk factors (diabetes, obesity, smoking, hypertension, and obesity). Meanwhile, these factors also provide a new perspective for the prevention of cognitive impairment and dementia.

Cognitive Performance and Diabetic Retinopathy: What Your Eyes Can Reveal About Your Brain

BACKGROUND

Diabetic retinopathy (DR) is a chronic diabetes complication. People with Type 2 Diabetes Mellitus (T2DM) have two times the risk for dementia, suggesting it is a new chronic diabetes complication.

OBJECTIVE

Evaluate the association of DR with cognitive performance in a T2DM population.

METHODS

Cross-sectional study with 400 T2DM adults from whom socio-demographic, clinical, laboratory data were collected, and screening test for depression symptoms (Patient Health Questionaire- 9 (PHQ-9)), Mini-Mental State Examination (MMSE), Semantic Verbal Fluency Test, Trail Making Test A and B, Word Memory test were performed. All cognitive test scores were converted into Global Cognition z-Score (GCS(z)). The association between GCS(z) < 0 with DR was performed using a multivariate binary logistic regression model adjusted for age ≥ 65 years, school years ≤ 6 years, DM duration ≥ 10 years, depression symptoms score > 9 at PHQ-9, arterial hypertension, physical activity, diabetic retinopathy, macular edema, and cardiovascular disease.

RESULTS

After exclusions, the 251 eligible patients were 56.6% female, with a mean age of 61.1 (±9.8) years, DM duration of 12.6 (±8.9) years, and 7.6 (±4.2) years of school education. DR prevalence was 46.5%. Multivariate Logistic Regression Model showed an association between DR and GCS(z) < 0, with odds ratio (CI95%) of 2.50 (1.18-5.34), adjusted for age, low education level, arterial hypertension and depression symptoms (OD and CI95% respectively: 5.46(2.42-12.34); 12.19 (5.62-26.46); 2.55 (0.88-7.39); 3.53 (1.55-8.07)).

CONCLUSION

In this T2DM population, having DR increased the chance for worse cognitive performance even when adjusted for age, low education level, presence of arterial hypertension, and depression symptoms.

Associations between Visual Acuity and Cognitive Decline in Older Adulthood: A 9-Year Longitudinal Study

OBJECTIVE

Emerging evidence suggests low vision may be a modifiable risk factor for cognitive decline. We examined effects of baseline visual acuity (VA) on level of, and change in, cognitive test performance over 9 years.

METHOD

A population-based sample of 1,621 participants (average age 77 years) completed a comprehensive neuropsychological evaluation and VA testing at baseline and reassessed at nine subsequent annual visits. Linear regression modeled the association between baseline VA and concurrent cognitive test performance. Joint modeling of a longitudinal sub-model and a survival sub-model to adjust for attrition were used to examine associations between baseline VA and repeated cognitive test performance over time.

RESULTS

Better baseline VA was associated cross-sectionally with younger age, male sex, greater than high school education, and higher baseline neuropsychological test scores on both vision-dependent (B coefficient range -0.163 to -0.375, p = .006 to <.001) and vision-independent tests (-0.187 to -0.215, p = .003 to .002). In longitudinal modeling, better baseline VA was associated with slower decline in vision-dependent tests (B coefficient range -0.092 to 0.111, p = .005 to <.001) and vision-independent tests (-0.107 to 0.067, p = .007 to <.001).

CONCLUSIONS

Higher VA is associated with higher concurrent cognitive abilities and slower rates of decline over 9 years in both vision-dependent and vision-independent tests of memory, language, and executive functioning. Findings are consistent with emerging literature supporting vision impairment in aging as a potentially modifiable risk factor for cognitive decline. Clinicians should encourage patient utilization of vision assessment and correction with the added aim of protecting cognition.

Visual and cognitive functioning among older adults with low vision before vision rehabilitation: A pilot study

Introduction

The occurrence of age-related vision changes is inevitable. However, some of these changes can become pathological. Research indicates that vision and hearing loss is correlated with age-related cognitive decline, and with a higher risk of developing dementia due to Alzheimer's disease. Low vision rehabilitation could possibly be a protective factor against cognitive decline, as it provides the clients with compensatory strategies to overcome their visual deficits.

Objectives and hypothesis

The aim of this pilot study was to assess correlations between visual and cognitive functions in older adults referred for low vision rehabilitation. We hypothesized that more severe impairment of visual acuity and contrast sensitivity would be correlated with more advanced levels of cognitive impairment. The second objective was to examine which of these correlations would remain significant once established variables that influence cognition are statistically removed (e.g., age, education).

Methods

Thirty-eight older adults (age range: 66-97 years old) with a visual impairment (acuity <20/70) were recruited before the onset of their low vision rehabilitation. They underwent vision (reading acuity, reading speed, contrast sensitivity), hearing (audiogram, speech-in-noise perception) and cognitive (global cognition, memory, executive functions) testing, and demographic information was obtained.

Results and discussion

Correlations among global cognition and visual aid use, memory and reading speed, memory and contrast sensitivity, memory, and visual aid use, and between executive functions and contrast sensitivity were significant. Correlations between contrast sensitivity and memory, as well as between global cognition and visual aid use remained significant after controlling for age and education. The present study is relevant to clinicians who are assessing the cognitive status of older adults, such as neuropsychologists, because it highlights the importance of considering low vision when administering neuropsychological tests, especially to persons who have not yet received rehabilitation for their visual impairment.

The Parietal Lobe in Alzheimer’s Disease and Blindness

The progressive aging of the population will notably increase the burden of those diseases which leads to a disabling situation, such as Alzheimer’s disease (AD) and ophthalmological diseases that cause a visual impairment (VI). Eye diseases that cause a VI raise neuroplastic processes in the parietal lobe. Meanwhile, the aforementioned lobe suffers a severe decline throughout AD. From this perspective, diving deeper into the particularities of the parietal lobe is of paramount importance. In this article, we discuss the functions of the parietal lobe, review the parietal anatomical and pathophysiological peculiarities in AD, and also describe some of the changes in the parietal region that occur after VI. Although the alterations in the hippocampus and the temporal lobe have been well documented in AD, the alterations of the parietal lobe have been less thoroughly explored. Recent neuroimaging studies have revealed that some metabolic and perfusion impairments along with a reduction of the white and grey matter could take place in the parietal lobe during AD. Conversely, it has been speculated that blinding ocular diseases induce a remodeling of the parietal region which is observable through the improvement of the integration of multimodal stimuli and in the increase of the volume of this cortical region. Based on current findings concerning the parietal lobe in both pathologies, we hypothesize that the increased activity of the parietal lobe in people with VI may diminish the neurodegeneration of this brain region in those who are visually impaired by oculardiseases.

Association of Visual, Hearing, and Dual Sensory Impairment With Incident Dementia

Introduction

The relationship between sensory impairments and the risk of dementia is inconclusive. We aim to investigate the association of visual impairment (VI), hearing impairment (HI), and dual sensory impairment (DSI) with incident dementia.

Methods

The UK Biobank study recruited more than 500,000 participants aged 40-69 years across the United Kingdom. Participants with available visual acuity (VA) measurements and speech-reception-threshold (SRT) information and free of dementia at the baseline assessment were included in the analysis. VI was defined as VA worse than 0.3 LogMAR units and HI were defined as an SRT of -5.5 dB or over. DSI was defined as the presence of both VI and HI. Incident dementia was identified through linked data to primary care or hospital admission records and death registries. Multivariable Cox proportional hazard regression models were used to examine the association of VI, HI, and DSI with incident dementia.

Results

Among 113,511 participants (mean age: 56.8 ± 8.09 years, female: 54.4%), a total number of 1,135 (1.00%) cases of incident dementia were identified during a median follow up period of 11.1 years [interquartile range (IQR): 10.9-11.4 years]. The incidence of dementia showed significant differences among the non-sensory impairment (NSI) group, VI-only group, HI-only group, and DSI group (p < 0.001). After adjusting for demographic, lifestyle, health, and genetic factors, isolated VI (HR = 1.50, 95% CI: 1.06-2.12, p = 0.023), isolated HI (HR = 1.42, 95% CI:1.20-1.69, p < 0.001), and DSI (HR = 1.82, 95% CI: 1.10-3.00, p = 0.020) were independently associated with higher risks of incident dementia.

Conclusions

Visual, hearing, and dual sensory impairments were associated with an increased risk of developing dementia, suggesting that visual and hearing impairments are modifiable risk factors that can be targeted to prevent dementia.

Longitudinal Changes in Hearing and Visual Impairments and Risk of Dementia in Older Adults in the United States

Importance

Hearing and vision problems are individually associated with increased dementia risk, but the impact of having concurrent hearing and vision deficits, ie, dual sensory impairment (DSI), on risk of dementia, including its major subtypes Alzheimer disease (AD) and vascular dementia (VaD), is not well known.

Objective

To evaluate whether DSI is associated with incident dementia in older adults.

Design, Setting, and Participants

This prospective cohort study from the Cardiovascular Health Study (CHS) was conducted between 1992 and 1999, with as many as 8 years of follow-up. The multicenter, population-based sample was recruited from Medicare eligibility files in 4 US communities with academic medical centers. Of 5888 participants aged 65 years and older in CHS, 3602 underwent cranial magnetic resonance imaging and completed the modified Mini-Mental State Examination in 1992 to 1994 as part of the CHS Cognition Study. A total of 227 participants were excluded due to prevalent dementia, leaving a total of 3375 participants without dementia at study baseline. The study hypothesis was that DSI would be associated with increased risk of dementia compared with no sensory impairment. The association between the duration of DSI with risk of dementia was also evaluated. Data analysis was conducted from November 2019 to February 2020.

Exposures

Hearing and vision impairments were collected via self-report at baseline and as many as 5 follow-up visits.

Main Outcomes and Measures

All-cause dementia, AD, and VaD, classified by a multidisciplinary committee using standardized criteria.

Results

A total of 2927 participants with information on hearing and vision at all available study visits were included in the analysis (mean [SD] age, 74.6 [4.8] years; 1704 [58.2%] women; 455 [15.5%] African American or Black; 2472 [85.5%] White). Compared with no sensory impairment, DSI was associated with increased risk of all-cause dementia (hazard ratio [HR], 2.60; 95% CI, 1.66-2.06; P < .001), AD (HR, 3.67; 95% CI, 2.04-6.60; P < .001) but not VaD (HR, 2.03; 95% CI, 1.00-4.09; P = .05).

Conclusions and Relevance

In this cohort study, DSI was associated with increased risk of dementia, particularly AD. Evaluation of hearing and vision in older adults may help to identify those at high risk of developing dementia.

The Association Between Hearing Impairment, Vision Impairment, Dual Sensory Impairment, and Serious Cognitive Impairment: Findings from a Population-Based Study of 5.4 million Older Adults

Background:

Sensory impairments and cognitive impairment are increasing in scope due to the aging population.

Objective:

To investigate the association between hearing impairment, vision impairment, and dual sensory impairment with cognitive impairment among older adults.

Methods:

Secondary analysis of a combination of ten consecutive waves (2008–2017) of the nationally representative American Community Survey. The sample included 5.4 million community-dwelling and institutionalized older adults aged 65 and older. Bivariate and logistic regression models were conducted to examine the association hearing impairment, vision impairment, and dual sensory impairment with cognitive impairment.

Results:

After controlling for age, race, education, and income, older adults with only hearing impairment had more than double the odds of cognitive impairment (OR = 2.66, 95% CI = 2.64, 2.68), while older adults with only vision impairment had more than triple the odds of cognitive impairment (OR = 3.63; 95% CI = 3.59, 3.67). For older adults with dual sensory impairment, the odds of cognitive impairment were eight-fold (OR = 8.16; 95% CI = 8.07, 8.25). Similar trends were apparent in each sex and age cohort.

Conclusion:

Hearing and vision impairment are both independently associated with cognitive impairment. However, dual sensory impairment is associated with substantially higher odds of cognitive impairment, even after controlling for sociodemographic characteristics. Practitioners working with older adults may consider treatment for sensory impairments and cognitive impairment concurrently. Future research is needed to determine if the association is causal, and to investigate the effectiveness of common methods of treatment for sensory impairment for reducing the prevalence of cognitive impairment.

Longitudinal Association Between Self-Reported Sensory Impairments and Episodic Memory among Older Adults in China: A Prospective Cohort Study

Sensory impairments, such as visual and hearing impairments, and cognitive decline are prevalent among mid-age and older adults in China. With 4-year longitudinal data from the China Health and Retirement Longitudinal Study, we assessed the association between self-reported sensory impairments and episodic memory. Multivariate linear mixed-effects models were used to estimate the association of baseline sensory impairment in 2011-2012 with cognitive decline at 2- and 4-year follow-up visits. Among the 13,097 participants, longitudinal associations were identified between having hearing loss (β = -0.14, 95% CI: -0.22, -0.05), having both poor hearing and vision (β = -0.14, 95% CI: -0.23, -0.04) and decline in immediate word recall over 4 years, compared to those without self-reported sensory impairment. In addition, these associations were more significant among those aged 60 and older and among women. Further research is needed to investigate these associations in the longer term, providing evidence to support interventions that can prevent or delay sensory impairments and preserve cognitive functions in older adults.

Concurrent vision and hearing impairment associated with cognitive dysfunction in a population aged 85+ years: the Ural Very Old Study

OBJECTIVE

To assess the prevalence of vision impairment, hearing impairment and dual sensory impairment (DSI) as combination of vision and hearing impairment, in association with cognitive dysfunction in a population aged 85+ years.

METHODS

The cross-sectional population-based Ural Very Old Study, conducted in rural and urban Bashkortostan, Russia, between 2017 and 2020, included a detailed ocular and systemic examination with assessment of moderate to severe vision impairment (MSVI)/blindness (best-corrected visual acuity <6/18), moderate to severe hearing loss (MSHL) and cognitive function.

SETTING

A rural and urban area in Bashkortostan, Russia.

PARTICIPANTS

Out of 1882 eligible individuals aged 85+ years, 1526 (81.1%) individuals participated.

PRIMARY AND SECONDARY OUTCOME MEASURES

Prevalence of vision, hearing and DSI and cognitive dysfunction.

RESULTS

The study included 731 (47.9%) individuals (mean age 88.1±2.7 years; median 87 years, range 85-98 years) with measurements of MSVI/blindness, MSHL and cognitive function. The prevalence of MSVI/blindness, MSHL, DSI and dementia were 51.8% (95% CI 48.2% to 55.5%), 33.1% (95% CI 29.7% to 36.5%), 20.5% (95% CI 17.8% to 23.5%) and 48.2% (95% CI 44.5% to 51.8%), respectively. Lower cognitive function score was associated with lower visual acuity (p<0.001) and higher hearing loss score (p=0.03), after adjusting for older age (p=0.001), rural region of habitation (p=0.003), lower educational level (p<0.001) and higher depression score (p<0.001). Higher dementia prevalence was associated with higher MSHL prevalence (OR 2.18 95% CI 1.59 to 2.98; p<0.001), higher MSVI/blindness prevalence (OR 2.09, 95% CI 1.55 to 2.81; p<0.001) and higher DSI prevalence (OR 2.80, 95% CI 1.92 to 4.07; p<0.001).

CONCLUSIONS

In this very old, multiethnic population from Russia, DSI (prevalence 20.5%), as compared with hearing impairment (OR 2.18) and vision impairment alone (OR 2.09), had a stronger association (OR 2.80) with dementia. The findings show the importance of hearing and vision impairment, in particular their combined occurrence, for dementia prevalence in an old population.

Combined effects of handgrip strength and sensory impairment on the prevalence of cognitive impairment among older adults in Korea

Older adults commonly experience concurrent lower handgrip strength and sensory impairment. However, previous studies have analyzed the individual effects of either handgrip strength or sensory impairment on cognitive impairment. To address this gap, this study investigated the combined effects of handgrip strength and sensory impairment on cognitive impairment among older adults. In total, 2930 participants aged 65 and older were analyzed using 2014–2018 data from the Korean Longitudinal Study of Aging. Participants underwent assessments of handgrip strength (grip dynamometer), sensory impairment (self-reported responses), and cognitive impairment (Korean version of the Mini-Mental State Examination). Low handgrip strength, compared to normal handgrip strength, was associated with cognitive impairment. In participants with low handgrip strength, vision and hearing impairment were associated with cognitive impairment (odds ratio [OR] 1.36, 95% confidence interval [CI] 1.06–1.75; OR 2.58, 95% CI 1.77–3.78, respectively) compared to those with normal handgrip strength. Participants with low handgrip strength and dual sensory impairment had the highest OR for cognitive impairment (OR 3.73, 95% CI 2.65–5.25). Due to the strong association of low handgrip strength and dual sensory impairment with cognitive impairment, people living with low handgrip strength and dual sensory impairment should be classified as a high-risk group for cognitive impairment and should be prioritized for interventions.

Eye disease and mortality, cognition, disease, and modifiable risk factors: an umbrella review of meta-analyses of observational studies

Globally, 2.2 billion people live with some form of vision impairment and/or eye disease. To date, most systematic reviews examining associations have focused on a single eye disease and there is no systematic evaluation of the relationships between eye diseases and diverse physical and mental health outcomes. Moreover, the strength and reliability of the literature is unclear. We performed an umbrella review of observational studies with meta analyses for any physical and/or mental comorbidities associated with eye disease. For each association, random-effects summary effect size, heterogeneity, small-study effect, excess significance bias and 95% prediction intervals were calculated, and used to grade significant evidence from convincing to weak. 34 studies were included covering 58 outcomes. No outcomes yielded convincing evidence, six outcomes yielded highly suggestive results (cataract positively associated with type 2 diabetes, open-angled glaucoma positively associated with myopia and diabetes, diabetic retinopathy positively associated with cardiovascular disease and cardiovascular mortality, and retinopathy of prematurity positively associated with chorioamnionitis), eight outcomes yielded suggestive results (diabetic retinopathy positively associated with all-cause mortality and depression, diabetic macular oedema positively associated with dyslipidaemia, cataract positively associated with gout, nuclear sclerosis positively associated with all-cause mortality, open angled glaucoma positively associated with migraine and hypertension, and age-related macular degeneration positively associated with diabetes), and 18 outcomes yielded weak evidence. Results show highly suggestive or suggestive evidence for associations between several types of eye diseases with several comorbid outcomes. Practitioners and public health policies should note these findings when developing healthcare policies.

Vision impairment and cognitive decline among older adults: a systematic review

OBJECTIVES

There has been increasing epidemiological research examining the association between vision impairment (VI) and cognitive impairment and how poor vision may be a modifiable risk factor for cognitive decline. The objective of this systematic review is to synthesise the published literature on the association of VI with cognitive decline, cognitive impairment or dementia, to aid the development of interventions and guide public policies pertaining to the relationship between vision and cognition.

METHODS

A literature search was performed with Embase, Medline and Cochrane library databases from inception to March 2020, and included abstracts and articles published in peer-reviewed journals in English. Our inclusion criteria included publications that contained subjective/objective measures of vision and cognition, or a diagnosis of VI, cognitive impairment or dementia. Longitudinal or cross-sectional studies with ≥100 participants aged >50 years were included. The search identified 11 805 articles whose abstracts underwent screening by three teams of study authors. Data abstraction and quality assessment using the Effective Public Health Practice Project Quality Assessment Tool were performed by one author (NN). 10% of the articles underwent abstraction and appraisal by a second author (LA/VV), results were compared between both and were in agreement.

RESULTS

110 full-text articles were selected for data extraction, of which 53 were cross-sectional, 43 longitudinal and 14 were case-control studies. The mean age of participants was 73.0 years (range 50-93.1). Ninety-one (83%) of these studies reported that VI was associated with cognitive impairment.

CONCLUSION

Our systematic review indicates that a majority of studies examining the vision-cognition relationship report that VI is associated with more cognitive decline, cognitive impairment or dementia among older adults. This synthesis supports the need for additional research to understand the mechanisms underlying the association between VI and cognitive impairment and to test interventions that mitigate the cognitive consequences of VI.

Hearing loss, cognition, and risk of neurocognitive disorder: evidence from a longitudinal cohort study of older adult Australians

Addressing midlife hearing loss could prevent up to 9% of new cases of dementia, the highest of any potentially modifiable risk factor identified in the 2017 commissioned report in The Lancet. In Australia, hearing loss is the second-most common chronic health condition in older people, affecting 74% of people aged over 70. Estimates indicate that people with severe hearing loss are up to 5-times more likely to develop dementia, but these estimates vary between studies due to methodological limitations. Using data from the Sydney Memory and Aging Study, in which 1,037 Australian men and women aged between 70 and 90 years were enrolled and completed biennial assessments from 2005-2017, investigations between hearing loss and baseline cognitive performance as well as longitudinal risk of neurocognitive disorder were undertaken. Individuals who reported moderate-to-severe hearing difficulties had poorer cognitive performances in the domains of Attention/Processing Speed and Visuospatial Ability, and on an overall index of Global Cognition, and had a 1.5-times greater risk for the neurocognitive disorder during 6-years' follow-up. Hearing loss independently predicted risk for MCI but not dementia. The presence of hearing loss is an important consideration for neuropsychological case formulation in older adults with cognitive impairment. Hearing loss may increase cognitive load, resulting in observable cognitive impairment on neuropsychological testing. Individuals with hearing loss who demonstrate impairment in non-amnestic domains may experience benefits from the provision of hearing devices; This study provides support for a randomized control trial of hearing devices for improvement of cognitive function in this group.

Co-occurring Hearing Loss and Cognitive Decline in Older Adults: A Dual Group-Based Trajectory Modeling Approach

Hearing loss and cognitive impairments are both highly prevalent neurological complications for older adults. While there is growing evidence to suggest that these two conditions are interrelated, little research has been conducted that directly examines the progression and developmental trajectories of these complications contemporaneously. The aim of the study is to identify the distinct trajectory profiles for hearing loss and cognitive function in an older population over a 10-year period. Through dual trajectory modeling, the interrelationship, co-occurring movements, and overlaps between these two complications were examined. We also investigated the influence of hearing aid ownership on cognitive function trajectories. We utilized longitudinal data from 1,445 participants in the Blue Mountains Hearing Study (aged 55+ years) involving repeated measures from a population-based survey with audiometric hearing assessments. Cognitive function was assessed using the Mini-Mental State Examination (MMSE). The group-based trajectory modeling (GBTM) identified three trajectory profiles for both hearing loss and cognitive function in two older age groups (55-69 years and 70+ years). The outputs from the dual trajectories models showed the conditional probability for "no hearing loss" trajectories to be around 90% more likely to have "high-normal" cognitive function, demonstrating co-occurring overlap. In contrast, for "moderate to severe hearing loss" trajectories, the conditional probability drops to 65% and 79% for the 55-69 age group and 70+ age group respectively. There was also an increasing probability for "cognitive decline" conditional on the severity of hearing loss with 6.7%, 7.5%, and 8.7% for no hearing loss, mild hearing loss, and moderate to severe hearing loss trajectory groups. While we did not find any statistically significant difference in the influence of hearing aid use in the cognitive function trajectories, there was a consistent greater representation of non-hearing aid users in the trajectories with poorer cognitive function. This study found GBTM to identify trajectories that were in agreement with our current understanding of hearing loss and cognitive impairment in older adults. This study also adds to the existing evidence-base as dual trajectories demonstrated co-occurrence in developmental changes in these two common neurological complications for the older population.

Nine-year changes in self-reported problems with vision and hearing among older adults: do subjective age views matter?

OBJECTIVES

So far, little is known about linkages between subjective age views and long-term changes in vision and hearing.

METHOD

We examined the predictive role of two key measures of subjective age views (attitude toward own aging [ATOA]; aging-related cognitions comprising continuous growth, social loss, and physical decline) for changes in self-reported problems with vision and hearing over a period of up to 9 years. A subsample of the German Ageing Survey was used, consisting of 2,499 older adults.

RESULTS

Controlling for socio-demographic characteristics, self-rated health, and depressive symptoms, we found that with increasing age, more favorable ATOA scores, as well as higher scores on continuous growth and lower scores on physical decline, were associated with fewer self-reported vision problems at baseline. With advancing age, more favorable ATOA scores were also related with fewer hearing problems at baseline. However, among individuals with an older baseline age, more favorable ATOA scores were associated with a steeper increase in vision problems. Higher scores on continuous growth were related with less increase in hearing problems, independent of age.

CONCLUSION

Our findings suggest that subjective age views predict individuals' self-reported vision and hearing problems.

Vision impairment, vision correction, and cognitive decline among middle-aged and older Chinese: results from the China health and retirement longitudinal study

OBJECTIVES

To investigate the associations between vision impairment (VI), vision correction (VC), and cognitive function.

METHOD

We included 20,677 participants aged ≥45 years from the China Health and Retirement Longitudinal Study (2011-2015). Participants were grouped into no VI, distance VI (DVI) only, near VI (NVI) only, or both distance and near VI (DNVI), and VI(+)/VC(-), VI(+)/VC(+), VI(-)/VC(-), or VI(-)/VC(+) further at baseline. Cognitive function at baseline and subsequently every two years was applied as a dependent variable in a generalized estimating equation model.

RESULTS

DVI only, NVI only, and DNVI had significantly worse cognitive function over time than no VI (all p < .05). DNVI had significantly worse cognitive function over time than DVI only and NVI only (all p < .001). VI(+)/VC(+), VI(-)/VC(-), and VI(-)/VC(+) had significantly better cognitive function over time than VI(+)/VC(-) (all p < .05). VI(-)/VC(+) had significantly better cognitive function over time than VI(+)/VC(+) and VI(-)/VC(-) (all p < .05).

CONCLUSION

Cognitive function was worse in middle-aged and older Chinese with VI, especially in those with DNVI. VC was associated with better cognitive function over time regardless of the status of vision.

Can Cochlear Implantation in Older Adults Reverse Cognitive Decline Due to Hearing Loss?

INTRODUCTION

Older adults with late-onset hearing loss are at risk for cognitive decline. Our study addresses the question of whether cochlear implantation (CI) can counteract this potential influence. We investigated whether cognitive performance in older adults with severe and profound hearing loss improves 12 months after CI to a level comparable to controls with normal hearing, matched for age, sex, and education level.

DESIGN

This cohort study was performed at two tertiary referral centers. The study included 29 patients, of age between 60 and 80 years, with adult-onset, severe to profound bilateral sensorineural hearing loss and indication for CI (study group), as well as 29 volunteers with age-adjusted hearing abilities, according to the norm curves of ISO-702 9:2000-01, (control group). Before CI and 12 months after CI, participants completed a neurocognitive test battery including tests of global cognition, verbal and figural episodic memory, and executive functions (attentional control, inhibition, and cognitive flexibility).

RESULTS

Twelve months after CI, the performance of the study group improved significantly in global cognition, compared to the situation before CI. Differences in verbal episodic memory, figural episodic memory, and executive function were not significant. Moreover, the improvement of the study group was significantly larger only in global cognition compared to the control group. Noninferiority tests on the cognitive performances of the study group after CI revealed that comparable levels to normal hearing controls were reached only in global cognition, figural episodic memory (immediate recall), and attentional control. The improvement in global cognition was significantly associated with speech recognition 3 months after CI, but not with speech recognition 12 months after CI.

CONCLUSION

One year after CI, cognitive deficits in older individuals with adult-onset hearing loss, compared to normal-hearing peers, could only improve some cognitive skills.

Developing consensus-based referral criteria for low vision services in Australia

PURPOSE

To develop expert consensus on referral criteria for low vision services in Australia.

METHODS

In a modified online Delphi process, a panel of 38 Australian experts in low vision (including ophthalmologists, optometrists, orthoptists, occupational therapists, orientation and mobility professionals, researchers and managers) participated in three rounds of consensus building over a period of 5 months commencing in 2019. Initially, 90 statements were developed, addressing what should be included in best-practice low vision referral criteria, currently used criteria, timing of referral and responsibility for referral. By the third round, these had been reduced and refined to a total of four statements.

RESULTS

In three Delphi rounds, the expert panel produced three key recommendations for low vision referral: (1) that low vision referral should be based mainly on the impact of uncorrectable vision impairment on function and well-being; (2) clinical measures of visual acuity and visual field might be a secondary consideration and (3) it is important to fully inform a person about low vision services at an early stage of vision loss and to involve them in decision making about referral. There was consensus on the need for clear referral pathways and that both ophthalmologists and optometrists have primary responsibility to refer for low vision services.

CONCLUSIONS

Although recommendations and guidelines should not replace sound individual clinical judgement, promotion and adoption of these consensus recommendations could assist health care professionals in providing appropriate and timely referral for low vision services to the benefit of people with vision impairment.

Association between visual impairment and cognitive disorders in low-and-middle income countries: a systematic review

OBJECTIVES

Visual impairment and cognitive disorders are common among older people in Low-and Middle-Income Countries (LMIC). Several recent studies performed in High-Income Countries suggested that visual impairment is associated with cognitive disorders. However, no synthesis of current knowledge exists for LMIC.

METHODS

We have conducted an extensive literature search combining six databases and two grey literature databases. We searched for studies assessing the link between visual and cognitive impairments carried out in LMIC. The systematic search was performed up to 14th February 2019.

RESULTS

Overall, eight studies were included in this review. Among them, five studies were performed in Asia and seven studies had a cross-sectional design. Mean age of the participants varied from 64.2 to 76.2 years. Participants were most often females. Only three studies were specifically focused on the association between visual impairment and cognitive disorders. Out of the eight studies included, four reported a significant association; two showed a possible association and two did not retrieve any statistically significant effect. Heterogeneity in assessments of visual and cognitive impairments was high.

CONCLUSION

In LMIC, very few studies explored the association between visual and cognitive impairments among older people. The current review seems to suggest that visual impairment is associated with cognitive disorders in LMIC. However, further studies are required to improve the knowledge on this relationship. Improving vision, in particular through optical correction and cataract surgery, could potentially be easy pathways to reduce cognitive disorders incidence and to improve quality of life of people affected by this disorder.

Visual Impairment, Eye Disease, and 3-Year Cognitive Decline: The Canadian Longitudinal Study on Aging

PURPOSE

To examine the longitudinal association between vision-related variables and the 3-year change in cognitive test scores in a community-dwelling sample of adults and to explore whether sex, education, or hearing loss act as effect modifiers.

METHODS

Data came from two waves of a 3-year population-based prospective cohort study (Canadian Longitudinal Study on Aging), which consisted of 30,097 randomly selected people aged 45-85 years from 7 Canadian provinces. Visual impairment (VI) was defined as binocular presenting visual acuity worse than 20/40. Participants were asked if they had ever had a diagnosis of age-related macular degeneration (AMD), glaucoma, or cataract. Cognitive change over 3 years was examined by calculating the difference between baseline and follow-up scores for the Rey Auditory Verbal Learning Test (RAVLT) and the RAVLT delayed test (memory tests), the Controlled Oral Word Association Test (COWAT) and the Animal Naming Test (ANT) (verbal fluency tests), and the Mental Alternation Test (MAT) (processing speed test). Multiple linear regression was used.

RESULTS

VI, AMD, and cataract were not associated with 3-year changes on any of the 5 cognitive tests after adjusting for age, sex, ethnicity, education, income, smoking, diabetes, stroke, heart disease, and province. A report of glaucoma was associated with greater declines in MAT scores (β = -0.60, 95% CI -1.03, -0.18). No effect modification was detected.

CONCLUSIONS

Glaucoma was associated with worsening processing speed. Further research to confirm this finding and to understand the possible reason is necessary.

Association of visual impairment with cognitive decline among older adults in Taiwan

This study investigated the association between visual impairment and cognitive decline among the elderly in Taiwan. The data were obtained from a government-sponsored, annual physical examination program for elderly citizens ≥ 65 years in Taipei City during 2005-2012. Distance presenting visual acuity was measured using the Snellen chart. Visual impairment was classified into low vision and blindness. The Short Portable Mental Status Questionnaire (SPMSQ) was selected to measure cognitive decline. The confounding factors including age, sex, sociodemographic factors: living status, marital status, education level, health behaviors: smoking, alcohol consumption, betel nut chewing, and physical comorbidities: BMI, hypertension, diabetes, cholesterol and triglyceride were collected for analysis. We recruited 105,208 participants and 4542 (4.3%) have abnormal SPMSQ. The abnormal SPMSQ had significantly higher prevalence of low vision (44.52% vs 18.79%) and blindness (8.89% vs 0.93%) compared with normal SPMSQ. The hazard ratios of abnormal SPMSQ in low vision and blindness were 2.34 (95% CI 2.17-2.52), and 5.13 (95% CI 4.50-5.85), after adjustment for confounders. In conclusion, visual impairment was independently and significantly associated with greater incident cognitive decline among elderly Asian people. Prevention of visual impairment may help to reduce the incidence of cognitive decline in the aged Asian population.