Association of Glaucoma and Cataract with Incident Dementia: A 5-Year Follow-Up in the Shanghai Aging Study

Associations of cataract, cataract surgery with dementia risk: A systematic review and meta-analysis of 448,140 participants

BACKGROUND

Cataract is the leading cause of blindness around the world. Previous investigations have assessed the relationship between cataract, cataract surgery and dementia risk, but their results remain controversial. Herein, we conducted a meta-analysis to evaluate the associations between cataract, cataract surgery and the risk of dementia.

METHODS

We systemically screened the literature from three electronic databases PubMed, EMBASE and CENTRAL until April 2023. The data were collected by two independent researchers. The hazard ratios (HRs) or odds ratios (ORs) from eligible studies with 95% confidence intervals (CIs) were adjusted into the risk ratios (RRs), which were pooled using the random-effects model.

RESULTS

A total of nine studies with 448,140 participants reported the associations between cataract or cataract surgery and the risk of dementia were included in this meta-analysis. The outcomes of our pooled analysis indicated that cataract was associated with an increased risk of all-cause dementia (RR = 1.24, 95% CI, 1.14-1.35, p < .00001), Alzheimer's disease (RR = 1.22, 95% CI, 1.10-1.35, p = .0002) and vascular dementia (RR = 1.29, 95% CI, 1.01-1.66, p = .04). Cataract surgery is associated with a reduction of the dementia risk (RR = 0.74, 95% CI, 0.67-0.81, p < .00001).

CONCLUSIONS

Current evidence from the existing studies supports that cataract is associated with an increased risk of dementia, and cataract surgery may be instrumental in reducing the risk of dementia in patients with cataract.

The risk of dementia or cognitive impairment in patients with cataracts: a systematic review and meta-analysis

OBJECTIVES

The aim of this study was to investigate whether cataract disease is associated with the risk of developing dementia or cognitive impairment.

METHODS

A systematic search of the literature in PubMed, the Extracts Database (Embase), the Cochrane Library and the Web of Science databases was performed from the inception data of each database until 1 September 2022. Sensitivity analyses were performed to assess the robustness and reliability of the overall findings. All extracted data were statistically analyzed using Stata software v.16.0. Publication bias was assessed using funnel plots and the Egger test.

RESULTS

There were 11 publications included in this study, which consisted of 489,211participants, spanning 10 countries from 2012 to 2022. Aggregation suggested that cataracts were associated with cognitive impairment (odds ratio [OR] = 1.32; 95% CI: 1.21-1.43; I 2 = 45.4.%; p = 0.000). The presence of cataracts is significantly associated with an increased risk of developing all-cause dementia (relative risk [RR] = 1.17; 95% CI: 1.08-1.26; I2 = 0.0%; p = 0.000). In subgroup analyses, having cataracts may increase the risk of Alzheimer's disease (hazard ratio [HR] = 1.28; 95% CI: 1.13-1.45; I2 = 0.0%; p = 0.000) and vascular dementia (HR = 1.35; 95% CI = 1.06-1.73; I2 = 0.0%, p = 0.015). The data from the Egger's test showed no significant evidence of publication bias.

CONCLUSIONS

Cataracts are associated with the risk of cognitive impairment and dementia, including Alzheimer's disease, and vascular dementia.

Relative Risks for Dementia among Individuals with Glaucoma: A Meta-Analysis of Observational Cohort Studies

PURPOSE

To investigate the relative risks (RRs) for dementia among individuals with glaucoma.

METHODS

We conducted a search of PubMed, Web of Science, Scopus, and Cochrane databases for observational cohort studies examining the association between glaucoma and dementia until March 2023. Two authors independently screened all titles and abstracts according to predefined inclusion and exclusion criteria. Pooled RR and 95% confidence intervals (CIs) were generated using random-effect models.

RESULTS

The meta-analysis included 18 cohort studies conducted in eight countries and involving 4,975,325 individuals. The pooled RR for the association between glaucoma and all-cause dementia was 1.314 (95% CI, 1.099-1.572; I2 = 95%). The pooled RRs for the associations of open-angle glaucoma with Alzheimer dementia and Parkinson disease were 1.287 (95% CI, 1.007-1.646; I2 = 96%) and 1.233 (95% CI, 0.677-2.243; I2 = 73%), respectively. The pooled RRs for the associations of angle-closure glaucoma with all-cause dementia and Alzheimer dementia were 0.978 (95% CI, 0.750-1.277; I2 = 17%) and 0.838 (95% CI, 0.421-1.669; I2 = 16%), respectively. No evidence of publication bias was detected in the Begg-Mazumdar adjusted rank correlation test (p = 0.47).

CONCLUSIONS

Based on current observational cohort studies, there is evidence supporting that glaucoma is a risk factor for dementia in the adult population.

The impact of sensory impairments and eye diseases on cognitive function in elderly Chinese: The mediating effects of social participation

Background

Sensory impairments and eye diseases increase the risk of cognitive decline, but little is known regarding their influence on cognitive function in elderly Chinese and the underlying mechanisms. We aimed to explore these influence mechanism from the social participation perspective.

Methods

We selected 2876 respondents aged ≥60 from the China Health and Retirement Longitudinal Study (CHARLS) conducted in 2013, 2015, and 2018. We assessed sensory impairments and eye diseases based on self-reported responses, and evaluated its relation to social participation and cognitive function by fixed-effects regression and mediation effect analysis over a five-year period.

Results

Respondents with visual impairment and cataracts had poor memory and mental status. Compared with near visual impairment, distance visual impairment was associated with a 1.7 times higher likelihood of cognitive decline (correlation coefficient (β) = -0.051; 95% confidence interval (CI) = -0.065, -0.036)). Respondents with hearing impairment had bad memory (β = -0.046; 95% CI = -0.065, -0.036), but not mental status. Social participation partially mediated the relationships of sensory impairments and cataracts with cognitive function in elderly Chinese. Individuals with sensory impairments affected by limited social participation reported a faster cognitive decline compared to those with eye disease.

Conclusions

We found that sensory impairments and eye diseases were negatively associated with cognitive function. Furthermore, sensory impairments and cataracts influence cognitive function partly via social participation. Our results have important theoretical and practical implications and suggests that early interventions for sensory impairments and eye diseases may improve the cognitive function of elderly people.

The association between cataract and incidence of cognitive impairment in older adults: A systematic review and meta-analysis

BACKGROUND

Cataract has been shown to be associated with an increased risk of cognitive impairment. However, the results of previous studies have been inconsistent. This systematic review and meta-analysis aimed to investigate the association between cataract and the incidence of cognitive impairment in older adults.

METHODS

A comprehensive search of electronic databases from inception to January 2023 was performed to identify relevant studies. Data were extracted from eligible studies and a meta-analysis was performed to calculate the pooled hazard ratio (HR) and 95% confidence interval (CI).

RESULTS

We included 13 studies with 25 study arms involving a total of 798,694 participants. Compared with participants without cataract, those with cataract had a higher risk of developing all-cause dementia (pooled HR: 1.22; 95% CI: 1.08-1.38; I²=86%; 9 studies), Alzheimer's disease dementia (pooled HR: 1.18; 95% CI: 1.07-1.30; I²=0%; 9 studies), vascular dementia (pooled HR: 1.21; 95% CI: 1.02-1.43; I²=77%;3 studies) and mild cognitive impairment (pooled HR: 1.30; 95% CI: 1.13-1.50; I²=0%;2 studies). There was no significant association between cataract and mixed dementia (pooled HR: 1.03; 95% CI: 0.52-2.04; I²=78%;2 studies). We assessed the risk of bias of the included studies using the Newcastle-Ottawa Scale and found that most of them had a low or moderate risk of bias. The number of studies in each meta-analysis ranged from two to nine, with more studies available for all-cause dementia and Alzheimer's disease dementia than for vascular dementia and mixed dementia.

CONCLUSIONS

The findings suggest that cataract may be associated with cognitive impairment in older adults. However, the causal relationship between cataract and cognition remains unclear and requires further investigation.

The Associations Between Cataracts and Alzheimer's Disease: A Bidirectional Two-Sample Mendelian Randomization Study

BACKGROUND

The relationship between cataracts and Alzheimer's disease (AD) has been reported in recent observational studies. However, it is still unclear whether a causal effect of cataracts on AD or reverse causation exists.

OBJECTIVE

To explore the association between cataracts and AD genetically, we performed a bidirectional two-sample Mendelian randomization study.

METHODS

We obtained genetic instrumental variables related to cataracts and AD from recently published genome-wide association studies (GWASs). SNP-outcome associations for AD were obtained from a GWAS with 111,326 cases and 677,663 controls. SNP-outcome associations for cataracts were drawn from two sources: a GWAS with 67,844 cases and 517,399 controls and the FinnGen consortium (42,843 cases and 262,698 controls). Inverse variance weighted (IVW) was used as the primary method for Mendelian randomization (MR) analyses.

RESULTS

No genetic evidence suggested that cataracts were associated with the risk of AD (IVW odds ratio =1.04, 95% confidence interval: 0.98-1.10, p=0.199). In contrast, an effect of genetically determined AD on a decreased risk of cataract was observed with suggestive evidence (IVW odds ratio =0.96, 95% confidence interval: 0.93-0.99, p=0.004). However, this result might be distorted by survival bias.

CONCLUSION

Genetically determined cataracts were not related to AD, as demonstrated by our study. In contrast, there was suggestive evidence that AD might prevent cataract development, but there might be potential survival bias. To define the exact association between the two diseases, more prospective research and studies on the pathogenesis are needed.

Identifying and addressing common contributors to nonadherence with ophthalmic medical therapy

PURPOSE OF REVIEW

To discuss common reasons for nonadherence and review existing and emerging options to reduce nonadherence with ocular medical therapy and optimize therapeutic outcomes.

RECENT FINDINGS

Nonadherence can arise from patient-related issues (e.g. physical, cognitive) and healthcare-related issues (e.g. cost, access to care). Multiple strategies have been developed and evaluated to overcome these barriers to adherence. Identifying nonadherence and its cause(s) facilitates the development of strategies to overcome it.

SUMMARY

Many common causes of nonadherence can be mitigated through a variety of strategies presented.

Risk of dementia in newly diagnosed glaucoma: a nationwide cohort study in Korea

PURPOSE

To investigate the risk of dementia in participants with newly diagnosed glaucoma.

DESIGN

A nationwide cohort study using authorized data provided by the Korean National Health Insurance Service (NHIS).

PARTICIPANTS

A total of 788,961 participants aged ≥ 45 years in 2006, who did not have dementia or glaucoma between 2002 and 2005, were included.

METHODS

Data were collected from a nationwide population-based retrospective cohort study using the Korean NHIS database. From January 2006 to December 2017, participants were tracked for the diagnosis of glaucoma or dementia using claims data. The prospective association between newly diagnosed glaucoma and the risk of dementia was investigated using a multivariable Cox proportional hazard model adjusted for age, sex, behavioral factors, and systemic and ocular comorbidities.

MAIN OUTCOME MEASURES

Hazard ratios and 95% confidence intervals for dementia development according to the parameters, including glaucoma diagnosis.

RESULTS

Overall, 7.0% of the participants developed dementia after an average of 7.4 years. A newly diagnosed glaucoma was associated with a higher risk of dementia (hazards ratio [HR] 1.89, 95% confidence interval [CI] 1.57 to 2.27) independent of age, sex, body mass index, income, smoking and drinking status, visual acuity, and other systemic comorbidities, such as diabetes, hypertension, stroke, and depression. An association between the risk of dementia and glaucoma was noted in participants with Alzheimer's disease (AD) but not in those with vascular dementia. The risk of dementia in relation to glaucoma was higher in older participants (HR = 3.15 (≥ 65 years) vs. 1.56 (< 65 years), P < 0.0001).

CONCLUSION

This nationwide cohort study found that individuals with newly diagnosed glaucoma were at a higher risk of developing dementia, particularly AD. This association was greater among older individuals in the studied population.

Associations of ophthalmic and systemic conditions with incident dementia in the UK Biobank

AIMS

To examine independent and interactive associations of ophthalmic and systemic conditions with incident dementia.

METHODS

Our analysis included 12 364 adults aged 55-73 years from the UK Biobank cohort. Participants were assessed between 2006 and 2010 at baseline and were followed up until the early of 2021. Incident dementia was ascertained using hospital inpatient, death records and self-reported data.

RESULTS

Over 1 263 513 person-years of follow-up, 2304 cases of incident dementia were documented. The multivariable-adjusted HRs (95% CI) for dementia associated with age-related macular degeneration (AMD), cataract, diabetes-related eye disease (DRED) and glaucoma at baseline were 1.26 (1.05 to 1.52), 1.11 (1.00 to 1.24), 1.61 (1.30 to 2.00) and (1.07 (0.92 to 1.25), respectively. Diabetes, heart disease, stroke and depression at baseline were all associated with an increased risk of dementia. Of the combination of AMD and a systemic condition, AMD-diabetes was associated with the highest risk for incident dementia (HR (95% CI): 2.73 (1.79 to 4.17)). Individuals with cataract and a systemic condition were 1.19-2.29 times more likely to develop dementia compared with those without cataract and systemic conditions. The corresponding number for DRED and a systemic condition was 1.50-3.24. Diabetes, hypertension, heart disease, depression and stroke newly identified during follow-up mediated the association between cataract and incident dementia as well as the association between DRED and incident dementia.

CONCLUSIONS

AMD, cataract and DRED but not glaucoma are associated with an increased risk of dementia. Individuals with both ophthalmic and systemic conditions are at higher risk of dementia compared with those with an ophthalmic or systemic condition only.

Inverse Association of APOE ε4 and Glaucoma Modified by Systemic Hypertension: The Canadian Longitudinal Study on Aging

Purpose

Studies examining the apolipoprotein E (APOE) ε4 allele and glaucoma are inconsistent, which could be due to interactions with other factors. We examined the relationship between the APOE ε4 allele and glaucoma and intraocular pressure in a large, population-based random sample and explored whether the APOE ε4 allele interacted with systemic hypertension.

Methods

Data came from the Canadian Longitudinal Study on Aging, a population-based study that included 24,655 adults ages 45 to 85 years old in the European ancestry cohort. APOE genotypes were derived from single-nucleotide polymorphisms rs429358 and rs7412. Participants were asked about a prior diagnosis of glaucoma from a doctor. Corneal compensated intraocular pressure (IOP) was measured using the Reichart Ocular Response Analyzer.

Results

Having an APOE ε4 allele was associated with a lower odds of glaucoma after adjusting for age, sex, IOP, and the top 10 population structure principal components (odds ratio [OR] = 0.83; 95% confidence interval [CI], 0.69-0.98; P = 0.033). A novel statistically significant interaction was found in that having an APOE ε4 allele was only associated with glaucoma in those without systemic hypertension (OR = 0.62; 95% CI, 0.46-0.85) although it was not associated in those with it (OR = 0.97; 95% CI, 0.79-1.21) (interaction term P value = 0.017). APOE ε4 was not associated with IOP (β = -0.01; 95% CI, -0.13 to 0.10).

Conclusions

Evidence increasingly points to the APOE ε4 allele having protective benefits against glaucoma, but this association was limited to those without systemic hypertension. Further research is needed to understand the biological mechanisms for these findings and the treatment potential they hold.

Reduced brain subcortical volumes in patients with glaucoma: a pilot neuroimaging study using the region-of-interest-based approach

Background

While numerous neuroimaging studies have demonstrated that glaucoma is associated with smaller volumes of the visual cortices in the brain, only a few studies have linked glaucoma with brain structures beyond the visual cortices. Therefore, the objective of this study was to compare brain imaging markers and neuropsychological performance between individuals with and without glaucoma.

Methods

We identified 64 individuals with glaucoma and randomly selected 128 age-, sex-, and education level-matched individuals without glaucoma from a community-based cohort. The study participants underwent 3 T brain magnetic resonance imaging and neuropsychological assessment battery. Regional cortical thickness and subcortical volume were estimated from the brain images of the participants. We used a linear mixed model after adjusting for potential confounding variables.

Results

Cortical thickness in the occipital lobe was significantly smaller in individuals with glaucoma than in the matched individuals (β = − 0.04 mm, P = 0.014). This did not remain significant after adjusting for cardiovascular risk factors (β = − 0.02 mm, P = 0.67). Individuals with glaucoma had smaller volumes of the thalamus (β = − 212.8 mm³, P = 0.028), caudate (β = − 170.0 mm³, P = 0.029), putamen (β = − 151.4 mm³, P = 0.051), pallidum (β = − 103.6 mm³, P = 0.007), hippocampus (β = − 141.4 mm³, P = 0.026), and amygdala (β = − 87.9 mm³, P = 0.018) compared with those without glaucoma. Among neuropsychological battery tests, only the Stroop color reading test  score was significantly lower in individuals with glaucoma compared with those without glaucoma (β = − 0.44, P = 0.038).

Conclusions

We found that glaucoma was associated with smaller volumes of the thalamus, caudate, putamen, pallidum, amygdala, and hippocampus.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12883-022-02807-x.

The APOE E4 Allele Is Associated with Faster Rates of Neuroretinal Thinning in a Prospective Cohort Study of Suspect and Early Glaucoma

Purpose

Design

Participants

Methods

Main Outcome Measures

Results

Conclusions

Individuals with and without normal tension glaucoma exhibit comparable performance on tests of cognitive function

AIM

To evaluate aspects of cognition impacted by individuals with and without normal tension glaucoma.

METHODS

Fifty normal tension glaucoma (NTG) and 50 control patients ≥50y of age were recruited from the UCSF Department of Ophthalmology. Demographic data and glaucoma parameters were extracted from electronic medical records for both groups. Tests of executive function [Executive Abilities: Measures and Instruments for Neurobehavioral Evaluation and Research (EXAMINER)] and learning and memory [California Verbal Learning Test-Second Edition (CVLT-II)] were administered to both NTG and controls. Race, handedness, best-corrected visual acuity, maximum intraocular pressure, optic nerve cup-to-disc ratio, visual field and optic nerve optical coherence tomography parameters, and a measure of general health (Charlson Comorbidity Index) were compared between NTG and controls as well as within NTG subgroups. Multivariate linear regression was used to compare group performances on the EXAMINER battery and CVLT-II while controlling for age, sex, and years of education.

RESULTS

NTG and controls were comparable with respect to age, sex, race, education, handedness, and the Charlson Comorbidity Index (P>0.05 for all). Performance on the EXAMINER composite score and the CVLT-II did not differ between NTG and controls (P>0.05 for both).

CONCLUSION

This is the first prospective study in which the cognitive function of subject with NTG were evaluated using a comprehensive, computerized neurocognitive battery. Subjects with NTG do not perform worse than unaffected controls on tests of executive function, learning, and memory. Results do not support the hypothesis that individuals with NTG are at higher risk for cognitive dysfunction and/or dementia.

Glaucoma Is Not Associated With Alzheimer's Disease or Dementia: A Meta-Analysis of Cohort Studies

Background: Previous studies evaluating the relationships of glaucoma with Alzheimer's disease (AD) and dementia showed inconsistent results. We performed a meta-analysis of cohort studies to evaluate the association between glaucoma with incidence of AD, all-cause dementia, and non-AD dementia. Methods: Cohort studies which evaluated the association between glaucoma with incidence of AD, all-cause dementia, and non-AD dementia in adult population with multivariate analyses were identified by systematic search of PubMed, Embase, and Cochrane's Library databases. A random-effects model incorporating the potential intra-study heterogeneity was used for the meta-analysis. Results: Eleven cohort studies including 4,645,925 participants were included. Results showed that compared to those without glaucoma at baseline, adult patients with glaucoma was not independently associated with increased incidence of AD [adjusted risk ratio (RR): 1.03, 95% confidence interval (CI): 0.93-1.05, P = 0.55; I ² = 83%], all-cause dementia (adjusted RR: 1.08, 95% CI: 0.97-1.19, P = 0.15; I ² = 79%), or non-AD dementia (adjusted RR: 1.05 95% CI: 0.91-1.21, P = 0.49; I ² = 82%). Sensitivity analyses by excluding one study at a time did not significantly affect the results of the meta-analyses. Moreover, subgroup analyses showed consistent results in meta-analysis of prospective or retrospective cohort studies, and in meta-analysis of patients with primary open-angle glaucoma or primary angle-closure glaucoma (P-values for subgroup difference all > 0.05). Conclusions: Current evidence from cohort studies did not support that glaucoma is an independent risk factor of AD, all-cause dementia, or non-AD dementia in adult population.

Visual Impairment, Eye Diseases, and Dementia Risk: A Systematic Review and Meta-Analysis

BACKGROUND

Visual impairment and eye diseases have been associated with dementia, though with mixed findings and often in cross-sectional studies.

OBJECTIVE

To identify prospective studies investigating associations between visual impairment or common eye diseases and risk of all-cause dementia or key dementia subtypes.

METHODS

We searched Medline, PsycINFO, and Embase from inception to January 2020. We also conducted backward and forward citation searches of included studies and set up alerts to identify studies published after the search date. Random-effects meta-analysis was used to combine adjusted estimates across studies.

RESULTS

Thirty studies met our eligibility criteria. For visual impairment, pooled estimates indicated an increased risk of all-cause dementia (37,705 participants, 3,415 cases, risk ratio [RR] = 1.38, 95%confidence interval [CI]: 1.19-1.59, I2 = 28.6%). Pooled estimates also suggested an increased dementia risk associated with cataract (6,659 participants, 1,312 cases, hazard ratio [HR] = 1.17, 95%CI 1.00-1.38, I2 = 0.0%) and diabetic retinopathy (43,658 participants, 7,060 cases, HR = 1.34, 95%CI 1.11-1.61, I2 = 63.9%), respectively. There was no evidence of an association between glaucoma (175,357 participants, 44,144 cases, HR = 0.97, 95%CI 0.90-1.04, I2 = 51.5%) or age-related macular degeneration (7,800,692 participants, >  2,559 cases, HR = 1.15, 95%CI 0.88-1.50, I2 = 91.0%) and risk of dementia, respectively.

CONCLUSION

As visual impairment, cataract, and diabetic retinopathy are associated with an increased likelihood of developing dementia, early diagnosis may help identify those at risk of dementia. Given most causes of visual impairment are treatable or preventable, the potential for dementia prevention warrants further investigation.

Associations of Vision Impairment and Eye Diseases With Memory Decline Over 4 Years in China and the United States

PURPOSE

To examine whether vision impairment and eye diseases are independently associated with memory decline in older adults.

DESIGN

Cohort study.

METHODS

We included 8,315 participants aged 50-94 years in China Health and Retirement Longitudinal Study (CHARLS) from China and 8,939 participants aged 50-95 years in Health and Retirement Study (HRS) from the United States in our analysis.

RESULTS

During 4.0 years' follow-up, the composite memory decreased by 0.16 points in CHARLS. During 3.9 years' follow-up, the composite memory decreased by 0.51 in HRS. Distance vision impairment was inversely associated with an annual change in composite memory (β [95% CI]: -0.07 [-0.12, -0.01]) and immediate memory (-0.04 [-0.07, -0.02]) in CHARLS, and the corresponding values in HRS were -0.19 (-0.34, -0.05) and -0.07 (-0.13, -0.00), respectively. Near vision impairment was inversely associated with an annual change in delayed memory in CHARLS and composite memory, immediate memory, and delayed memory in HRS. In HRS, the association between distance vision impairment and memory decline was observed in individuals aged <65 years (β [95% CI]: -0.54 [-0.78, -0.30]) but not in those aged ≥65 years (-0.01 [-0.20, 0.18]). Cataract surgery or glaucoma was not significantly associated with memory decline in either CHARLS or HRS.

CONCLUSION

Distance vision impairment was independently associated with an accelerated rate of memory decline in both China and the United States. Near vision impairment was predictive of decline in delayed memory in China and of decline in composite, immediate, and delayed memory in the United States.

The Association between Vision Impairment and Incidence of Dementia and Cognitive Impairment: A Systematic Review and Meta-analysis

TOPIC

The magnitude and direction of the association between vision impairment and incident dementia and cognitive impairment in prospective cohort studies was estimated by systematic review and meta-analysis. The global burden of dementia associated with vision impairment then was estimated.

CLINICAL RELEVANCE

Because a predominant proportion of vision impairment is preventable or treatable, investigating its association with dementia may help to identify an important modifiable factor for the prevention of dementia.

METHODS

A literature search was conducted using PubMed, Embase, Web of Science, and Google Scholar on September 15, 2020. Relative risks (RRs) were pooled using random-effects models and stratified analyses for subgroups representing different study characteristics. Publication bias was evaluated with funnel plots and the Egger test. The global burden of dementia associated with vision impairment was estimated based on the Global Burden of Disease Study data on the prevalence of dementia and vision impairment.

RESULTS

In the meta-analysis of 14 prospective cohort studies with 6 204 827 participants and 171 888 dementia patients, the pooled RR associated with vision impairment was 1.47 (95% confidence interval [CI], 1.36-1.60). In the meta-analysis of 12 prospective cohort studies with 45 313 participants and 13 350 patients with cognitive impairment, the pooled RR was 1.35 (95% CI, 1.28-1.41). Stratified analyses showed that the associations of vision impairment with incident dementia and cognitive impairment were similar across methods of vision assessment, length of follow-up, and study quality. The global number of people with dementia associated with moderate or severe vision impairment in 2016 was 2.1 million (80% uncertainty interval, 1.0-3.3 million), which accounted for 4.7% (95% CI, 2.3%-7.5%) of the global burden of dementia. Economic inequality was significant for the burden of dementia associated with vision impairment.

DISCUSSION

The overall quality of the body evidence was low because of the observational design of the studies included in the analysis. Vision impairment is associated with an increased risk of both dementia and cognitive impairment in older adults. Screening and treating vision impairment, especially in low- and middle-income countries, may help to alleviate the global burden of dementia.

Glaucoma, but not cataracts, predicts lower verbal fluency performance: 3.8-year follow-up from the ELSA-Brasil study

Glaucoma, cataracts, and cognitive decline are most common in older ages. Although cross-sectional studies showed that these disorders are associated, follow-up studies are lacking. To investigate this issue, baseline and follow-up data from the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil) were employed. We evaluated participants ≥ 55 years-old at follow-up without diagnosis of dementia, stroke, and other eye conditions except for glaucoma and cataracts. Cognition was evaluated using delayed word recall, verbal fluency, and trail making (version B) tests. Regression models were employed to investigate associations between glaucoma and cognition, adjusted by several confounders. Out of 3,867 participants, 379 and 118 presented cataracts and glaucoma, respectively. Only glaucoma was apredictor of lower verbal fluency (B = -0.23, 95% CI -035 to -012, p< 0.001). Other associations were not significant (ps>0.57). Our results suggest that glaucoma may be related to declining cognition.