Visual impairment in older institutionalised Canadian seniors with dementia

Access to primary eye care for people living with dementia: a call to action for primary care practitioners to 'think vision'

Access to allied health services offers significant benefits for people living with dementia, yet access is currently fragmented and inconsistent. The 2023-2024 budget allocated AU$445million to further enable general practice-led, multidisciplinary teams, with integrated care located within practices, including employment of allied health professionals. Such team care models are recognised by The Royal Australian College of General Practitioners as vital to delivery of high-quality care for older adults. They are especially relevant for over 250,000 Australians who live with dementia in the community. However, not all allied health professionals are currently based within general practices. Future, sustainable general practice-led models of multidisciplinary care that connect patients with external allied health providers could be considered for a comprehensive and collaborative approach to care. Our focus is on people living with dementia, who are at greater risk of preventable vision impairment. Poor vision and/or ocular health can be detected and managed through regular eye examinations, which are predominantly delivered by community-based optometrists in Australia, in a primary care capacity. However, people living with dementia are also less likely to have regular eye examinations. In this paper, we highlight the value of ensuring access to primary eye care services as part of post-diagnosis dementia care. We illustrate the important role of primary care practitioners in building and sustaining connections with allied health professions, like optometry, through effective referral and interprofessional communication systems. This can help break down access barriers to dementia-friendly eye care, through promoting the importance of regular eye tests for people living with dementia.

Primary eyecare provision for people living with dementia: what do we need to know?

Dementia comprises a group of brain disorders characterised by loss of cognitive function. Sensory loss, predominantly vision (the focus of this review) and hearing, is a significant problem for people living with dementia. Eyecare practitioners such as optometrists therefore play an important role in identifying and addressing vision-related care needs. To support provision of high quality "dementia-friendly" eyecare, this scoping review summarises recent primary research findings and available clinical practice guidelines, to identify research gaps relating to vision and dementia, and make recommendations for future research and clinical practice. The review set a priori guidelines for the population, concept and context based on the review questions. Primary research papers (2016-2021) were included via 3-step search strategy: preliminary search to index terms, full search, search reference lists of included articles for further inclusions. Additionally, websites of eyecare professional bodies in English-speaking countries were searched to identify current clinical eyecare practice guidelines relating to dementia. Study characteristics (e.g. country, study design) were reported descriptively. Patterns within findings/recommendations from included sources were identified using thematic analysis and reported as themes. 1651 titles/abstracts and 161 full-text articles were screened for eligibility. Three clinical practice guidelines were also identified. The final review included 21 sources: 18 primary research papers and 3 clinical practice guidelines. The thematic analysis reported five key themes: Diagnosis/Screening, dementia progression, findings on clinical visual testing, tailored approach to care, improving care. This scoping review demonstrated limited information about current practices of optometrists working with people living with dementia. Recent evidence reinforces the continuing need for improved eyecare for people living with dementia, taking into account their specific needs with an individualised approach. Up-to-date practical recommendations are synthesised for eyecare providers before, during and after a consultation with a person living with dementia, to better support their care.

Prevalence of visual impairment in older people living with dementia and its impact: a scoping review

BACKGROUND AND OBJECTIVES

Visual impairment (VI) and dementia both increase with age, and it is likely that many older people are living with both conditions. This scoping review aims to investigate the prevalence and types of VI among older people living with dementia, and the impact of VI on older people living with dementia and their caregivers.

METHODS

This scoping review used Arksey and O'Malley's methodological framework. Studies in any setting involving people living with dementia and some assessment of either VI, eye diseases causing VI or the impact of VI were included.

RESULTS

Thirty-six studies were included. Thirty-one studies reported the prevalence of VI in older people living with dementia, while ten studies reported on impacts of VI on people living with dementia. Only one study reported on impacts on caregivers. The prevalence of VI or specific eye diseases among older people living with dementia ranged from 0.2 to 74%. The impacts of VI on older people living with dementia included increased use of hospital services, increased disability and dependency, reduced social engagement, negative emotions, increased abnormal behaviours, loss of hobbies, difficulty in using visual aids or memory aids, and greater Neuropsychiatric Inventory symptoms. And the impacts on caregivers included increased conflict and physical exhaustion.

CONCLUSION

VI is common in older people living with dementia and is associated with negative impacts on those with dementia and their caregivers. However, heterogeneity between studies in terms of setting and method for assessing and defining VI make it difficult to compare findings among studies. Further research is needed, particularly assessing the impact on caregivers.

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.

Bidirectional Association between Visual Impairment and Dementia Among Older Adults in the United States Over Time

PURPOSE

Although visual impairment (VI) has been associated with worse cognitive performance among older adults, the temporal relationship between the 2 remains subject to debate. Our objective was to investigate the longitudinal impact of VI on cognitive function and vice versa.

DESIGN

Retrospective, time-to-event study.

PARTICIPANTS

National Health and Aging Trends Study (NHATS) participants from 2011 to 2018 cycles.

METHODS

A total of 10 676 participants aged 65 years and older were included. Cox proportional hazards regression models evaluated the impact of baseline VI on subsequent dementia and impact of baseline dementia on subsequent VI. Models were adjusted for potential confounding variables, including demographics, clinical comorbidities, and hearing and physical function limitations.

MAIN OUTCOME MEASURES

Hazard ratio (HR) for incident dementia among participants with baseline self-reported VI and HR for incident VI among participants with baseline dementia.

RESULTS

Of the 10 676 participants included in the analysis, approximately 40% were aged 65-74 years, 40% were aged 75-84 years, and the remaining 20% were aged 85 years and older. The majority were female (59%), and 68% self-identified as non-Hispanic White. Among participants with normal cognitive status at baseline, subsequent dementia was observed in 1753 (16%), and among participants with normal self-reported vision at baseline, subsequent VI was reported in 2371 (22%). In adjusted regression models, participants with baseline VI had higher likelihood of developing dementia over subsequent follow-up (HR, 2.3; 95% confidence interval [CI], 2.0-2.6; P < 0.001). Likewise, participants with baseline dementia had a higher likelihood of developing self-reported VI over time (HR, 2.5; 95% CI, 2.2-2.8; P < 0.001).

CONCLUSIONS

Self-reported VI in the US Medicare population is associated with greater dementia likelihood over time, and dementia is similarly associated with greater VI likelihood over time. Associations are likely multifactorial and bidirectional and could be explained by intervening variables in the path from VI to dementia, or vice versa, or by common risk factors for pathological processes in both eyes and brain. These findings suggest the need for early identification of older adults with visual compromise and consideration of visual disability in the cognitively impaired.

Visual Performance and Cortical Atrophy in Vision-Related Brain Regions Differ Between Older Adults with (or at Risk for) Alzheimer's Disease

BACKGROUND

Visual impairment is associated with deficits in cognitive function and risk for cognitive decline and Alzheimer's disease (AD).

OBJECTIVE

The purpose of this study was to characterize the degree of visual impairment and explore the association thereof with cortical atrophy in brain regions associated with visual processing in individuals with (or at risk for) AD.

METHODS

Using the Comprehensive Assessment of Neurodegeneration and Dementia (COMPASS-ND) dataset, we analyzed vision and brain imaging data from three diagnostic groups: individuals with subjective cognitive decline (SCD; N = 35), mild cognitive impairment (MCI; N = 74), and mild AD (N = 30). We used ANCOVAs to determine whether performance on reading acuity and contrast sensitivity tests differed across diagnostic groups. Hierarchical regression analyses were applied to determine whether visual performance predicted gray matter volume for vision-related regions of interest above and beyond group membership.

RESULTS

The AD group performed significantly worse on reading acuity (F(2,138) = 4.12, p <  0.01, ω 2 = 0.04) compared to the SCD group and on contrast sensitivity (F(2,138) = 7.6, p <  0.01, ω 2 = 0.09) compared to the SCD and MCI groups, which did not differ from each other. Visual performance was associated with volume in some vision-related structures beyond clinical diagnosis.

CONCLUSION

Our findings demonstrate poor visual performance in AD and that both group membership and visual performance are predictors of cortical pathology, consistent with the idea that atrophy in visual areas and pathways contributes to the functional vision deficits observed in AD.

Screening for Vision Impairments in Individuals with Dementia Living in Long-Term Care: A Scoping Review

Vision impairments are prevalent, but underdiagnosed in individuals with dementia living in long-term care (LTC). Effective screening tools could identify remediable vision problems. This scoping review was conducted to identify vision screening tests used with individuals with dementia and assesses their suitability for administration by nurses in LTC. A literature search using the Arksey and O’Malley (2005) method included research articles, conference proceedings, and dissertations. Data were included from participants over 65 years of age with a diagnosis of probable dementia. A panel of vision experts evaluated the suitability of the candidate vision tests. The search yielded 179 publications that met the inclusion criteria. Of 134 vision tests that were identified, 19 were deemed suitable for screening by nurses in LTC. Tests screened for acuity (12), visual field (1), anatomy (2), color vision (2), and general visual abilities (2). Tests were excluded because of complexity of interpretation (90), need for specialized training (83), use in research only (57), need for specialized equipment (54), not assessing visual function (44), long test duration (21), uncommonness (13), and needing an act reserved for specialists (7). Psychometric properties were not often reported for tests. Few of the tests identified had been validated for use with individuals with dementia. Based on our review, few tests were deemed suitable for use by nurses to assess this population in LTC. Identifying appropriate tools to screen vision in individuals with dementia is a necessary first step to interventions that could potentially improve functioning and quality of life.

Dry Eyes, Ocular Lubricants, and Use of Systemic Medications Known or Suspected to Cause Dry Eyes in Residents of Aged Care Services

Ocular issues are common, burdensome, and under-researched among residents of aged care services. This study aims to investigate the prevalence of dry eyes or use of ocular lubricants among residents, and the possible association with systemic medications known or suspected to cause dry eyes. A cross-sectional study of 383 residents of six aged care services in South Australia was conducted. Data were extracted from participants' medical histories, medication charts, and validated assessments. The main exposure was systemic medications known to cause, contribute to, or aggravate dry eyes. The primary outcome was documented dry eyes or regular administration of ocular lubricants. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for the association between systemic medications and dry eyes/use of ocular lubricants. Dry eyes were documented for 53 (13.8%) residents and 98 (25.6%) residents were administered ocular lubricants. Overall, 116 (30.3%) residents had documented dry eyes/used ocular lubricants. Of these, half (n = 58) were taking a medication known to cause, contribute to, or aggravate dry eyes. Taking one or more medications listed as known to cause dry eyes was associated with having dry eyes/use of ocular lubricants (OR 1.83, 95% CI 1.15-2.94). In sub-analyses, no individual medication was associated with dry eyes/use of ocular lubricants. Dry eyes and use of ocular lubricants are common in residential aged care. Our hypothesis generating findings suggest the need for further research into the clinical significance of systemic medications as a possible cause of dry eyes.

Retinal nerve fiber layer thickness is associated with hippocampus and lingual gyrus volumes in nondemented older adults

OBJECTIVES

Abnormal retina structures, such as thinner retinal nerve fiber layer (RNFL), have been frequently reported in patients with Alzheimer's disease (AD). However, the association between RNFL and brain structures in cognitively normal adults remains unknown. We therefore set out to conduct a cross-sectional investigation to determine whether RNFL thickness is associated with brain structure volumes in nondemented older adults.

METHODS

We measured RNFL thickness by optical coherence tomography and brain structure volumes by 3 T magnetic resonance imaging. Cognitive function was assessed using the Chinese version of Repeatable Battery for the Assessment of Neurological Status. Pearson correlation was initially employed to screen for the potential associations among RNFL thickness, brain structure volumes and cognitive function. And then, multivariable linear regression models were conducted to further examine such associations adjusting for possible confounding factors, including age, sex, years of education and the estimated total intracranial volume (eTIV).

RESULTS

113 participants (≥ 65 years old) were screened and 80 of them (mean age: 68 ± 5.3 years; 48% male) were included in the final analysis. RNFL thickness in temporal quadrant was associated with medial temporal lobes volumes [unadjusted: r = 0.155, P = 0.175; adjusted: β = 0.205 (0.014, 0.383), P = 0.035], and especially associated with the hippocampus volume [unadjusted: r = 0.213, P = 0.062; adjusted: β = 0.251 (0.060, 0.435), P = 0.011] after adjusted for age, sex, years of education and eTIV. Moreover, it showed that RNFL thickness in inferior quadrant [unadjusted: r = 0.221, P = 0.052; adjusted: β = 0.226 (0.010. 0.446), P = 0.041] was significantly associated with occipital lobes volumes after the adjustment of age, sex, years of education and eTIV, and selectively associated with the substructure of lingual gyrus volume [unadjusted: r = 0.223, P = 0.050; adjusted: β = 0.278 (0.058, 0.487), P = 0.014]. In addition, average RNFL thickness was associated with the cognitive domain of visuospatial/constructional [unadjusted: r = 0.114, P = 0.322; adjusted: β = 0.216 (0.006, 0.426), P = 0.044] after the adjustment in these nondemented older adults.

CONCLUSIONS

Quadrant-specific associations exist between RNFL thickness and brain regions vulnerable to aging or neurodegeneration in older adults with normal cognition. These findings would promote further investigations into using RNFL as a noninvasive and less expensive biomarker of neurocognitive aging and AD-related neurodegeneration.

Prevalence and Associated Factors of Uncorrected Refractive Error in Older Adults in a Population-Based Study in France

Importance

Uncorrected refractive error (URE) is a common cause of visual impairment, but its prevalence in groups of older adults who could be pragmatic targets for improving optical correction remains unknown.

Objectives

To estimate the prevalence of URE in older adults, particularly in those with age-related eye disease and those who are unable to attend an outpatient clinic, and to identify the factors associated with URE.

Design, Setting, and Participants

This population-based cross-sectional analysis included 707 adults 78 years or older from the Alienor Study in Bordeaux, France. Data were collected from February 12, 2011, through December 21, 2012, and analyzed from November 1, 2017, through July 7, 2018.

Main Outcomes and Measures

Uncorrected refractive error was defined as the presenting distance visual acuity in the better-seeing eye improved by at least 5 letters on the Early Treatment Diabetic Retinopathy Study chart (≥1 line on the logMAR chart) using the best-achieved optical correction. Multivariate logistic regressions were used to determine the factors associated with URE.

Results

The study population of 707 adults 78 years or older (64.8% women; mean [SD] age, 84.3 [4.4] years) had a prevalence of URE of 38.8% (95% CI, 35.2%-42.5%). Prevalence was high for participants with eye disease (range, 35.0% [95% CI, 28.4%-42.0%] to 44.1% [95% CI, 27.2%-62.1%], depending on the disease) and those without eye disease (30.1%; 95% CI, 24.0%-36.7%). Prevalence was higher in participants who were examined at home (because they could not come to the clinic) than in those examined at the clinic (49.4% [95% CI, 42.8%-55.9%] vs 33.5% [95% CI, 29.2%-37.9%]; P < .001). Having an eye examination performed at home (odds ratio [OR], 1.64; 95% CI, 1.13-2.37), living alone (OR, 0.65; 95% CI, 0.47-0.90), and having the perceptions that the ophthalmologist consultation fees are too expensive (OR, 1.94; 95% CI, 1.12-3.36) and that declining visual acuity is normal with aging (OR, 1.47; 95% CI, 1.04-2.08) were all associated with URE.

Conclusions and Relevance

These study results show that the prevalence of URE was high in this population and suggest that preventive strategies aimed at enhancing optical correction could be directed to all older adults and to specific groups by implementing at-home eye examinations for those who have difficulties attending an outpatient clinic and by focusing on those with eye disease who probably already have a regular ophthalmologic follow-up. More studies are needed to evaluate prevalence of URE in different populations and countries with various eye care systems.

Agreement on the use of sensory screening techniques by nurses for older adults with cognitive impairment in long-term care: a mixed-methods consensus approach

OBJECTIVE

Based on two scoping reviews and two environmental scans, this study aimed at reaching consensus on the most suitable sensory screening tools for use by nurses working in long-term care homes, for the purpose of developing and validating a toolkit.

SETTING

A mixed-methods consensus study was conducted through two rounds of virtual electronic suitability rankings, followed by one online discussion group to resolve remaining disagreements.

PARTICIPANTS

A 12-member convenience panel of specialists from three countries with expertise in sensory and cognitive ageing provided the ranking data, of whom four participated in the online discussion.

OUTCOME MEASURES

As part of a larger mixed-methods project, the consensus was used to rank 22 vision and 20 hearing screening tests for suitability, based on 10 categories from the Quebec User Evaluation of Satisfaction with Assistive Technology questionnaire. Panellists were asked to score each test by category, and their responses were converted to z-scores, pooled and ranked. Outliers in assessment distribution were then returned to the individual team members to adjust scoring towards consensus.

RESULTS

In order of ranking, the top 4 vision screening tests were hand motion, counting fingers, confrontation visual fields and the HOT-V chart, whereas the top 4 hearing screening tests were the Hearing Handicap Inventory for the Elderly, the Whisper Test, the Measure of Severity of Hearing Loss and the Hyperacusis Questionnaire, respectively.

CONCLUSIONS

The final selection of vision screening tests relied on observable visual behaviours, such as visibility of tasks within the central or peripheral visual field, whereas three of the four hearing tests relied on subjective report. Next, feasibility will be tested by nurses using these tools in a long-term care setting with persons with various levels of cognitive impairment.