Prevalence of Glaucoma in Hospitalized Older Adults with Alzheimer's Disease

Potential Retinal Biomarkers in Alzheimer's Disease

Alzheimer's disease (AD) represents a major diagnostic challenge, as early detection is crucial for effective intervention. This review examines the diagnostic challenges facing current AD evaluations and explores the emerging field of retinal alterations as early indicators. Recognizing the potential of the retina as a noninvasive window to the brain, we emphasize the importance of identifying retinal biomarkers in the early stages of AD. However, the examination of AD is not without its challenges, as the similarities shared with other retinal diseases introduce complexity in the search for AD-specific markers. In this review, we address the relevance of using the retina for the early diagnosis of AD and the complex challenges associated with the search for AD-specific retinal biomarkers. We provide a comprehensive overview of the current landscape and highlight avenues for progress in AD diagnosis by retinal examination.

Frequency of coexistent eye diseases and cognitive impairment or dementia: a systematic review and meta-analysis

OBJECTIVE

We aim to quantify the co-existence of age-related macular degeneration (AMD), glaucoma, or diabetic retinopathy (DR) and cognitive impairment or dementia.

METHOD

MEDLINE, EMBASE, PsycINFO and CINAHL were searched (to June 2020). Observational studies reporting incidence or prevalence of AMD, glaucoma, or DR in people with cognitive impairment or dementia, and of cognitive impairment or dementia among people with AMD, glaucoma, or DR were included.

RESULTS

Fifty-six studies (57 reports) were included but marked by heterogeneities in the diagnostic criteria or definitions of the diseases, study design, and case mix. Few studies reported on the incidence. Evidence was sparse but consistent in individuals with mild cognitive impairment where 7.7% glaucoma prevalence was observed. Prevalence of AMD and DR among people with cognitive impairment ranged from 3.9% to 9.4% and from 11.4% to 70.1%, respectively. Prevalence of AMD and glaucoma among people with dementia ranged from 1.4 to 53% and from 0.2% to 25.9%, respectively. Prevalence of DR among people with dementia was 11%. Prevalence of cognitive impairment in people with AMD, glaucoma, and DR ranged from 8.4% to 52.4%, 12.3% to 90.2%, and 3.9% to 77.8%, respectively, and prevalence of dementia in people with AMD, glaucoma and DR ranged from 9.9% to 62.6%, 2.5% to 3.3% and was 12.5%, respectively.

CONCLUSIONS

Frequency of comorbid eye disease and cognitive impairment or dementia varied considerably. While more population-based estimations of the co-existence are needed, interdisciplinary collaboration might be helpful in the management of these conditions to meet healthcare needs of an ageing population.

TRIAL REGISTRATION

PROSPERO registration: CRD42020189484.

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.

Incidence of Dementia in Patients With Open-angle Glaucoma: A Population-based Study

PRECIS

In this population-based study of 509 open-angle glaucoma (OAG) patients over a 36-year period, we identified a decreased rate of developing dementia compared with the rate in the general population.

PURPOSE

The aim was to determine the incidence of dementia and Alzheimer disease (AD) among patients with OAG.

PATIENTS AND METHODS

Retrospective, population-based cohort study. All residents of Olmsted County, Minnesota (≥40 y) who were diagnosed with OAG between January 1, 1965 and December 31, 2000, were eligible for inclusion in this study. A total of 509 patients were included over the 36-year period. The cumulative probability of developing dementia was calculated and compared with the population risk of dementia.

RESULTS

Of the 509 patients included, 300 (58.9%) were female, the median age was 67.5 years, and 278 patients (54.6%) had primary OAG. Other subgroups were pseudoexfoliation in 15.1%, treated ocular hypertension in 14.1%, normal tension glaucoma in 10.6%, and pigmentary glaucoma in 5.5% of the patients. Respectively, 118 (23.0%) and 99 (19.4%) patients developed dementia and AD. The 10-year cumulative probability of developing dementia and AD was 12.0% and 9.9%, with a 95% confidence interval of 9.3%-15.3% and 7.5%-13%, respectively. The observed 10-year incidence of dementia and AD were significantly lower than the expected population incidence (19.0% and 19.0%; P<0.001). Older age at diagnosis of glaucoma was a strong predictor for the development of dementia by multivariate analysis (hazard ratio: 3.31, 95% confidence interval: 2.61-4.20, P<0.001).

CONCLUSION

The risk of developing dementia or AD was decreased in OAG patients compared with the general population. OAG with onset at a later age may present as a different etiopathogenetic entity compared with onset at a younger age, and represent the optic nerve findings of generalized neurodegenerative processes.

Neurodegeneration in Alzheimer's disease and glaucoma: overlaps and missing links

The eye is said to be the window into the brain. Alzheimer’s disease (AD) and glaucoma both being diseases of the elderly, have several epidemiological and histological overlaps in pathogenesis. Both these diseases are neurodegenerative conditions. Over the years, a consensus has developed that both may be two ends of a singular spectrum of diseases. Epidemiological studies have shown that more Alzheimer’s patients may be suffering from glaucoma than general healthy population. Retinal ganglion cell damage is a characteristic of both diseases, along with discovery of amyloid-β and tau protein deposition in the retina and aqueous humor of eye. The latter two proteins are known to be pathognomonic of AD. Other pathways such as the insulin receptor pathway also seem to be affected in both diseases similarly. In spite of these overlaps, there are few missing links which still need more evidence, namely, intraocular pressure mechanisms, cerebrospinal fluid pressure and trans-lamina cribrosa pressure gradients, vascular autoregulation factors, etc. Several factors point towards a common pathogenesis at some level for both diseases and prospective studies are necessary to study the natural course of both diseases.

An Association Between Large Optic Nerve Cupping and Cognitive Function

PURPOSE

To determine if a larger cup-to-disc ratio is associated with poor cognitive function in postmenopausal women without glaucoma or ocular hypertension.

METHODS

We used data from the Women's Health Initiative (WHI) hormone trial, originally designed to test effects of hormone therapy (HT) on various health outcomes. Large cup-to-disc ratio was defined as greater than 0.6 in either eye based on stereoscopic optic nerve photographs. Global cognitive function was assessed annually by Modified Mini-Mental State Examination (3MSE) in the WHI Memory Study. Exclusions were no information on optic nerve grading; no 3MSE scores at the time of the eye examination, ocular hypertension (intraocular pressure >23 mm Hg, Goldmann applanation tonometry), or glaucoma medication use. A generalized linear model for log-transformed 3MSE scores was used for determining the association between large cup-to-disc ratio and 3MSE scores, adjusting for age, race, diabetes, body mass index, cardiovascular disease, smoking, HT randomization, education, and diabetic retinopathy.

RESULTS

Analyses included 1636 women (mean age ± standard deviation, 69.57 ± 3.64 years; 90.39% white). Of those, 122 women had large cup-to-disc ratio. The mean 3MSE scores in women with vs without large cup-to-disc ratio were 95.4 ± 6 vs 96.6 ± 5. In the adjusted model, women with large cup-to-disc ratio had statistically significantly lower 3MSE scores, compared with those without large cup-to-disc ratio, yielding the predicted mean difference in 3MSE scores of 0.75 with a standard error of 0.05 units (P = .04).

CONCLUSIONS

Postmenopausal women who had large cup-to-disc ratio without glaucoma or ocular hypertension exhibited lower global cognitive function. Further investigation is warranted. NOTE: Publication of this article is sponsored by the American Ophthalmological Society.

Association between Open-Angle Glaucoma and the Risks of Alzheimer's and Parkinson's Diseases in South Korea: A 10-year Nationwide Cohort Study

We aimed to investigate the risks of Alzheimer’s (AD) and Parkinson’s disease (PD) in the 10 years following diagnosis of open-angle glaucoma (OAG) using a nationwide cohort. This propensity score-matched retrospective cohort study included 1,025,340 subjects from the Korean National Health Insurance Service National Sample Cohort database. The OAG group (n = 1,469) included patients who were initially diagnosed with OAG between 2004 and 2007, and the subjects in the comparison group were matched in a 1:5 ratio using propensity scores. Cox regression analyses were performed to investigate the risks of developing AD or PD. The diagnosis of OAG was significantly associated with an increased incidence of AD (hazard ratio [HR] = 1.403, 95% confidence interval [CI] 1.180–1.669, p < 0.001), but not PD (HR = 0.995, 95% CI 0.620–1.595, p = 0.983) after adjusting for possible confounding factors. In subgroup analyses, participants with OAG aged ≥65 years were more likely to develop AD compared with those aged <65 years, and female OAG patients had a greater risk of developing AD than males. Patients diagnosed with OAG have a higher risk of developing AD, but not PD, and the risk differed according to age and sex.

Glaucoma may be a non-memory manifestation of Alzheimer's disease in older people

BACKGROUND

The purpose of this paper was to examine whether glaucoma could be a non-memory manifestation of Alzheimer's disease in older people.

METHODS

We conducted a population-based, retrospective, case-control study to analyze the database of the Taiwan National Health Insurance Program. There were 1,351 subjects ≥65 years old with newly diagnosed Alzheimer's disease as the cases, and 5,329 subjects without any type of dementias as the controls during 2000-2011. The odds ratio (OR) and 95% confidence interval (CI) for the risk of Alzheimer's disease associated with glaucoma was estimated by the multivariable unconditional logistic regression model.

RESULTS

After controlling for confounders, the multivariable logistic regression model demonstrated that the adjusted OR of Alzheimer's disease was 1.50 in subjects with glaucoma (95% CI 1.19, 1.89), compared to subjects without glaucoma.

CONCLUSIONS

Older people with glaucoma are associated with 1.5-fold increased odds of Alzheimer's disease in Taiwan. Glaucoma may be a non-memory manifestation of Alzheimer's disease in older people. Further research is needed to confirm this issue.

Association Between Alzheimer's Disease and Glaucoma: A Study Based on Heidelberg Retinal Tomography and Frequency Doubling Technology Perimetry

Aim: To assess the frequency of glaucoma-like alterations in Alzheimer's disease (AD) patients using Heidelberg Retinal Tomograph III (HRT-3) and Frequency Doubling Technology (FDT) perimetry.

Methods: The study included 51 eyes of 51 AD subjects and 67 eyes of 67 age- and sex-matched controls. Subjects underwent an ophthalmological examination including measurements of intraocular pressure (IOP), Matrix FDT visual field testing, optic nerve head morphology and retinal nerve fiber layer thickness (RNFLt) assessment by slit-lamp biomicroscopy and HRT-3.

Results: The frequency of alterations was significantly higher in the AD group (27.5 vs. 7.5%; p = 0.003; OR = 4.69). AD patients showed lower IOP (p = 0.000) despite not significantly different values of central corneal thickness (CCT) between the groups (p = 0.336). Of all the stereometric parameters measured by HRT-3, RNFLt was significantly lower in AD patients (p = 0.013). This group also had significantly worse results in terms of Moorfields Regression Analysis (p = 0.027). Matrix showed significantly worse Mean Deviation (MD) (p = 0.000) and Pattern Standard Deviation (PSD) (p = 0.000) values and more altered Glaucoma Hemifield Test (p = 0.006) in AD patients. Pearson's R correlation test showed that Mini Mental State Examination is directly correlated with MD (R = 0.349; p = 0.034) and inversely correlated with PSD (R = −0.357; p = 0.030).

Conclusion: Patients with AD have a higher frequency of glaucoma-like alterations, as detected by the use of HRT-3. These alterations were not associated with elevated IOP or abnormal CCT values.